j- u/J/pgL?^ xyx 7 Biological Services Program FWS/OBS-80/27 November 1980 REHABILITATION AND CREATION OF SELECTED COASTAL HABITATS: Proceedings of a Workshop Fish and Wildlife Service U.S. Department of the Interior United States Department of the Interior FISH AND WILDLIFE SERVICE National Coastal Ecosystems Team NASA/SI i dell Computer Complex 1010 Gause Blvd. Slidell , Louisiana 70458 27 February 1981 Dear Colleague: The papers printed in the attached volume were presented at a workshop on Sapalo Island, Georgia in May 1976. Although the workshop often has been referred to as the "Marsh Rehabitation Workshop", the title "Rehabilatation and Creation of Selected Coastal Habitats" is more accurate. The workshop was designed to provide information on replanting methods for dune, marsh, submerged grasses and mangrove species throughout the United States. Experts from each major coastal area were called in to provide the workshop program. Wide distribution is being made to our basic mailing list. Additional copies are available in limited numbers from the National Coastal Ecosystems Team, 1U10 Gause Blvd., Slidell, LA 70458. If you have any comments, suggestions, or constructive criticism, welcomed here at the Team. they wi 1 1 be Sincerely, Robert E. Stewart, Jr. Team Leader The Biological Services Program was established within the U.S. F1sh and Wildlife Service to supply scientific Information and methodologies on key environmental issues that impact fish and wildlife resources and their supporting ecosystems. The mission of the program is as follows: • To strengthen the Fish and Wildlife Service in its role as a primary source of information on national fish and wild- life resources, particularly in respect to environmental impact assessment. • To gather, analyze, and present information that will aid decisionmakers 1n the identification and resolution of problems associated with major changes in land and water use. • To provide better ecological information and evaluation for Department of the Interior development programs, such as those relating to energy development. Information developed by the Biological Services Program is Intended for use in the planning and decisionmaking process to prevent or minimize the impact of development on fish and wildlife. Research activities and technical assistance services are based on an analysis of the issues, a determination of the decisionmakers involved and their information needs, and an evaluation of the state of the art to identify information gaps and to determine priorities. This is a strategy that will ensure that the products produced and disseminated are timely and useful. Projects have been initiated in the following areas: coal extraction and conversion; power plants; geothermal , mineral and oil shale develop- ment; water resource analysis, including stream alterations and western water allocation; coastal ecosystems and Outer Continental Shelf develop- ment; and systems inventory, including National Wetland Inventory, habitat classification and analysis, and information transfer. The Biological Services Program consists of the Office of Biological Services in Washington, D.C., which is responsible for overall planning and management; National Teams, which provide the Program's central scientific and technical expertise and arrange for contracting biological services studies with states, universities, consulting firms, and others; Regional Staffs, who provide a link to problems at the operating level; and staffs at certain Fish and Wildlife Service research facilities, who conduct in-house research studies. l Selected Coast >rkshop. Editors e, Biological [ WHO 1 >. ( DOCUMENT ) V COLLECTION/ _____[ RETURNED ==f===== — L Q ' astal re D m = □ ^^^S D ^^^2 ^— FWS/OBS-80/27 November 1980 REHABILITATION AND CREATION OF SELECTED COASTAL HABITATS: Proceedings of a Workshop James C. Lewis and Elaine W. Bunce Editors Project Officer Larry R. Shanks National Coastal Ecosystems Team U.S. Fish and Wildlife Service 1010 Gause Blvd. Slide!!, LA 70458 Published by Office of Biological Services Fish and Wildlife Service U.S. Department of the Interior Washington, DC 20240 DISCLAIMER The opinions, findings, conclusions, or recommendations expressed in these Proceedings are those of the authors and do not necessarily reflect the views of the U.S. Fish and Wildlife Service, nor does the mention of trade names or commercial products constitute endorsement or recommendation for use by the Federal Government. PREFACE The papers in these Proceedings were presented at a workshop held at Sapelo Island, Georgia, 16-20 May 1976. Although innumerable delays made earlier publication impossible, the editors believe that the papers still contain useful information which may be applied in the rehabilitation and creation of coastal habitats. We wish to thank the authors for their patience and cooperation in revising, and in some cases rewriting, their original papers. Comments or requests for this publication should be addressed to: Information Transfer Specialist National Coastal Ecosystems Team U.S. Fish and Wildlife Service NASA-SI idell Computer Complex 1010 Gause Blvd. SI idell, LA 70458 (504) 255-6511, FTS 685-6511 This report should be cited as follows: Lewis, J.C. and E.W. Bunce, eds. 1980. Rehabilitation and creation of selected coastal habitats: Proceedings of a workshop. U.S. Fish and Wild- life Service, Biological Services Program, Washington, DC. FWS/OBS-80/27. 162 pp. m CONTENTS PREFACE 111 TECHNIQUES FOR CREATING SALT MARSHES ALONG THE EAST COAST by Ernest D. Seneca 1 CREATION OF A SOUTHEASTERN UNITED STATES SALT MARSH ON DREDGED MATERIAL by Robert J. Reimold 6 TECHNIQUES FOR CREATING SALT MARSHES ALONG THE CALIFORNIA COAST by Herbert L. Mason 23 SALT MARSH CREATION IN THE PACIFIC NORTHWEST: CRITERIA, PLANTING TECHNIQUES, AND COSTS by Wilbur E. Ternyik 25 SALT MARSH SOIL DEVELOPMENT by John L. Gallagher 28 SALT MARSH SUBSTRATE INTERACTION: MICROORGANISMS by Roger B. Hanson . . 35 DETERIORATION OF MARSH IN SAN FRANCISCO BAY by Herbert L. Mason 53 SAND DUNE HABITAT CREATION ON THE PACIFIC COAST by Wilbur E. Ternyik . . 55 DUNE COMMUNITY CREATION ALONG THE ATLANTIC COAST by Ernest D. Seneca . . 58 MANGROVE SWAMP CREATION by Howard J. Teas 63 CREATION OF SEAGRASS BEDS by Ronald C. Phillips 91 TECHNIQUES FOR CREATING SEAGRASS MEADOWS IN DAMAGED AREAS ALONG THE EAST COAST OF THE U.S.A. by Anitra Thorhaug 105 COASTAL HABITAT DEVELOPMENT IN THE DREDGED MATERIAL RESEARCH PROGRAM by Hanley K. Smith 117 SALT MARSH CREATION: IMPACT OF HEAVY METALS by Wayne S. Gardner .... 126 MARSH CREATION: IMPACT OF PESTICIDES ON THE FAUNA, USE OF INFRARED PHOTOGRAPHY, DITCHING AND DIKING by Robert J. Reimold 132 MARSH CREATION: EFFECTS OF PESTICIDES ON THE FLORA by John L. Gallagher 136 NUTRIENT CYCLING IN COASTAL ECOSYSTEMS by L.R. Pomeroy 140 SALT MARSH CREATION: IMPACT OF SEWAGE by Evelyn Haines 148 THE PRICING AND EVALUATION OF NATURAL RESOURCES by Ronald M. North . . .154 TECHNIQUES FOR CREATING SALT MARSHES ALONG THE EAST COAST Ernest D. Seneca Department of Botany and Soil Science North Carolina State University Raleigh, North Carolina 27650 The information that I present is the result of research conducted by Dr. W. W. Woodhouse, Jr., Dr. S. W. Broome, and me in North Carolina. Suggested ref- erences include Woodhouse (1979) and Woodhouse et al . (1972, 1974, 1976). Our research efforts were supported by the Coastal Engineering Research Center, U.S. Army Corps of Engineers; the Uni- versity of North Carolina Sea Grant Pro- gram; and the North Carolina Coastal Re- search Program. I cannot speak with any authority about marsh creation results from other areas, except in North Caro- lina where we worked with a wide range of environmental conditions. Most of the substrates that we worked with in marsh establishment were sandy. Low regularly flooded salt marshes are flooded twice daily along the Atlan- tic coast (along the Gulf coast only once daily) and are dominated by smooth cordgrass, Spartina al terniflora. From Maine to Florida, these marshes vary along a latitudinal gradient of increas- ing temperature and decreasing daylight during the summer. Salt marshes may con- sist of only a narrow fringe seaward from irregularly flooded marsh or shrub communities in the mid-Atlantic region. From Cape Lookout, North Carolina, south- ward through South Carolina and Georgia, these marshes consist of broad expanses of smooth cordgrass. Along the Gulf coast these marshes may again consist of only a narrow fringe such as at Ocean Springs, Mississippi. Near Brownsville, Texas, is found the westernmost popula- tions of smooth cordgrass and here, too, they come in contact with mangrove which dominates tropical coastlines in pro- tected areas. The same species of smooth cordgrass supposedly occurs all along the coast from Maine to Texas, but we should understand that even though the adjacent populations may interbreed, there is considerable variation in mor- phological features and physiological responses from north to south. Some of this variation is genetic, and some of it is probably only due to local envi- ronmental conditions. We do not have all the answers concerning the variabil- ity, but we do know that there are local population variations and that in marsh establishment we should be aware of those variations in any material that we transplant very far from the source of the transplants. Planting material should not be used very far from the area where it was obtained. Certainly plants from Maine should not be planted in Georgia. We began thinking about marsh crea- tion or marsh initiation in the late summer of 1969, at which time Dr. Wood- house and I went to the Coastal Engi- neering Research Center, U.S. Army Corps of Engineers, in Washington, D.C., and talked with some of their personnel about marsh creation. They seemed in- terested, gave us some seed money, and we started our studies in the fall of 1969. At that time there was consider- able open water disposal of dredge mate- rial in North Carolina. North Carolina has about 2,400 km (1,500 mi) of nav- igable channels in its sounds and estu- aries, and the Corps' annual expendi- tures for channel maintenance in 1969 were around 2 to 3 million dollars. The idea of trying to stabilize the intertidal zone of this dredge material appealed to the Corps because stabiliza- tion could reduce the amount of material finding its way back into the same chan- nels from which it was dredged. In the- ory, it could cut down on channel main- tenance costs. Heretofore, nothing has been done to stabilize this material after it was cast out of the pipeline dredge, and through normal wind and wave action, much of it found its way right back into the same channels from which it was dredged. Although the situation has changed and there is no longer open water disposal, there are still areas where marsh can be established. Further, if willful destruction of marshland oc- curs, we now have the techniques and procedures whereby regulatory agencies or the courts can require restoration. One of our first attempts to create salt marsh was at a small dredge spoil island in the Pamlico Sound, where the tidal amplitude was only 15 to 30 cm (6 to 12 inches). We had two objectives in mind: to stablize the spoil material in the intertidal zone by transplanting smooth cordgrass and, in so doing, to develop marsh. Our first attempts were not mechanized. We marked off rows and working in teams of two, hand-planted with a dibble bar like foresters use to plant trees. Most plants were set on about a 91-cm (36-inch) center, 91 cm between plants within rows and 91 cm be- tween rows. We used whatever size transplants were available at the time and location but preferably took them from a sandy substrate. Plants from such an area were easy to dig and to separate, and had wel 1 -developed root systems. The small young shoots at the base of the stem (culm) were left attached. These young shoots are often responsible for growth and establishment of the transplant. We discovered that we could establish smooth cordgrass marsh with transplants in this manner. A single culm transplant has the poten- tial to grow into a plant with several hundred grams of dry matter accumulation in a 5-mo period. Although a substan- tial root system had developed under the substrate in this time, stabilization was not fully achieved until the end of the second aboveground growing season, or about 17 mo after planting. To plant larger areas, we scaled up the operation by using a farm tractor with a modified tobacco planter. Later, we put dual wheels on the back of the tractor and wider tires on the front for extra flotation, so that we could plant more unstable areas. Our planting sites from north to south indicate that we covered the North Carolina coast in our trials. Not all experiments were suc- cessful, but we covered a wide range of conditions. From north to south, the coastline varies not only in terms of latitude, but also in tidal amplitude from less than 0.3 m (1 ft) to more than 1.5 m (5 ft). The primary influence on tides along the northern part of the North Carolina coast is wind. However, the southern coast is almost exclusively under the influence of lunar tides. Strong southwest winds blowing across the northern sounds may hold water on planting for several days, or when a northeast wind blows, water may be held off of the plantings for several days. In contrast, on the southern coast there is a regular flooding regime e^ery day. Let us consider one experimental site and follow it through 3 or 4 yr. Snow's Cut, North Carolina, in the middle of the Cape Fear River, south of Wilmington, had spoil deposited on it about 60 days prior to planting. The substrate was about 96% sand, had a slope of about 2%, and was influenced by a tidal amplitude of about 1.5 m (5 ft). We obtained transplants from an area that was relatively sandy and within 1 km (0.6 mi) of the planting site. Again we used single-stem transplants. We hand-planted on 91-cm (36-inch) centers in April. By June, survival was deter- mined to be over 90%. By September, the rows were still discernable but con- siderable spread was evident. By spring of the following year, a lateral spread of about 1.5 m (5 ft) was recorded. By the spring of the second year, an ob- server could no longer clearly identify plant rows, and by the end of the second growing season, for all practical pur- poses, we had established a marsh. In terms of fauna and flora, the area was not entirely comparable to a natural marsh, but in terms of primary produc- tion, it exceeded that of many natural marshes in the vicinity. By the end of the second or third year, it would be difficult for anyone to determine that the area was an artifically created marsh. We sampled the grass to determine how much was produced at the end of each growing season by measuring biomass and counting the number of culms. We cut the vegetation at ground level and dug out the belowground material to a depth of 30 cm (12 inches). Five months after transplanting there were about 200 g (7 oz) of aboveground biomass per trans- plant. We found that each transplant had produced somewhat less than 100 g/m2 be- low ground. Productivity declined after the first 17 mo, and peak aerial stand- ing crop leveled off from the third through the fifth growing season at be- tween 1,200 and 1,300 g/niz. No matter now good a new marsh may look at the end of the first growing season, substrate stabilization has not been achieved. Two full aboveground growing seasons or about 17 mo are re- quired at our latitude to develop a very intricate root and rhizome network that binds the substrate together. We took samples from cores and from complete 0.25-m2 (2.7-ft?) plots dug out to a depth of 30 cm (12 inches) to make these determinations. Belowground estimates after the second growing season dropped from about 900 g/m2 to about 650 g/m? by the end of the fourth growing season. To facilitate making cost estimates of these techniques of marsh establish- ment, we determined the time required to dig and transplant. Transplants can be dug at the rate of about 150 to 200 transplants per man-hour and planted at the same rate with persons working in a two-man team. Transplants can be obtained about twice as rapidly with mechanical equip- ment. We established a smooth cordgrass nursery where we used broad-bladed plow which substrate about 10 to inches) to obtain plants. This loosened the plants so that a tractor-drawn cut beneath the 15 cm (4 to 6 technique teams of men, walking along behind the plow, could lift them out of the ground. By October, the nursery area from which transplants were removed in this manner in spring had completely recovered. In fact, the vigor of the plants in the nursery was improved by thinning the stand and by the action of the plow. When transplants cannot be used immediately, they can be stored in the trenches much the same as foresters heel in pine trees. Transplants can be cov- ered in a trench in the intertidal zone and stored for 6 to 8 weeks. Comparative tests indicate that there is very little difference in survival and productivity of transplants that have been stored and those that have been dug fresh. At times there may not be a coastal area available for a nursery. We have experimented with growing smooth cord- grass in a nursery near Raleigh, North Carolina, about 241 km (150 mi) from the coast. We called it a rice paddy because we surrounded it with a dike and irri- gated it. Fresh water was pumped into the nursery whenever it began to dry out. We took transplants and seeds from several different areas along the coast and put them in the nursery. After the first season, growth seemed comparable to what we had noted in the coastal nursery. The following spring we took some of these plants to the coast and compar- ed them with plants freshly dug from the coast. We could detect no significant differences between plants kept in the inland nursery for 1 yr versus those plants dug fresh from the coast and planted in a replicated test on the coast. Plants from seeds sown in the inland nursery that had never been exposed to saline conditions were also transplanted on the coast and compared to natural plants dug along the coast. Again, there were no significant differ- ences in growth and survival between nursery and natural plants. Obviously, smooth cordgrass can be produced in an interim nursery inland from the coast. What about seeding instead of transplanting? Can seeds be collected in quantity, incorporated into the sub- trate, germinated and developed into a marsh? We knew that natural seeding, at least in some areas, was quite preva- lent. Natural seeding is important in colonizing new areas. Initially we har- vested seeds by hand and tried several ways of incorporating them into the substrate. We scarified the substrate, broadcast seed, and scarified it again. We also used clay slurries to affix the seeds to the substrate so that wave action would not remove them, but this method failed. To harvest larger quantities of seeds we built a two-wheel -garden trac- tor with a cutting blade mounted on the front and a reel that brings the seed heads across the cutting blade where they fall into a canvas catchment bag. Harvesting seeds in this manner can re- sult in collection of enough seeds in about 5 man-hours to seed a hectare. We put the seeds in burlap sacks, stored them for about 1 mo in a coldroom and then ran them through a small grain thresher. Then we stored the threshed seeds, submerged in either instant ocean or estuarine water (25 ppt) in large plastic containers at about 2°C to 48C (36°F to 39°F). Seeds must be kept moist and they must be stored cold to retard germina- tion. If estuarine water or instant ocean is not used, some of the seeds will germinate after a few months. The two things that prevent germination are low temperatures and the salinity which acts as an osmotic barrier. To scale up the seeding operation we used a tractor-drawn, spike-toothed harrow to scarify the substrate. We seeded at the rate of about 100 viable seeds per square meter. Viability was determined on a per milliliter basis and converted to area! extent (100 viable seeds per square meter). After seeds were spread over the area, we again went over the area with the spike-toothed harrow and incorporated them into the substrate. After 5 mo we had a good stand of seedlings. By the end of the second growing season, there was a marsh comparable to one established from transplants. On certain dredge material depos- its, the fine sand may blow around and interfere with vegetation establishment. In seeding operations, it may be neces- sary to stop the sand from blowing on the young seedlings. Either a sand fence or vegetation can be used to catch the sand and prevent it from covering the young plants while they are very suscep- tible to burial . Many areas are relatively inaccess- ible with a tractor or heavy equipment. One such area was a low profile island which developed in the sound behind the main barrier island after the opening of an inlet. To plant this area, we had to devise equipment that was more mobile. We put dual wheels on a garden tractor and constructed a tool bar with several cultivator sweeps on it. It scarified the area like a spike-toothed harrow. An area about 4 to 4.8 ha (10 to 12 acres) was torn up in this manner and seeded in spring. It required about 7.5 man-hours to scarify and seed the area. Even though the area was very ex- posed, by the end of the first growing season about half of the area was occu- pied by the seedlings. Growth was not especially good, and part of the lack of vigor was probably due to the exposed situation and the high substrate salini- ties which were up to 40 ppt. Smooth cordgrass does not survive substrate salinities much above about 45 ppt. At the end of the third growing season a marsh had developed from seed. We fertilized some areas and ob- tained even better growth. Most sandy substrates require fertilization with nitrogen and phosphorus. Nitrogen should be applied at the rate of 57 kg/ha (50 lb/acre). Along the North Carolina coastline, we have to harvest seeds in early Octo- ber before full maturity to avoid losing the seed crop because of shattering. We harvest early enough to get the seeds as they are maturing; otherwise, the crop could be lost because the seeds will shatter in the first storm. Harvesting before full maturity does not affect viability since the seeds continue to develop. They can be taken to the lab- oratory and put in a coldroom at about 2°C (36°F) and stored temporarily before threshing. Seeds thresh better after being stored for about a month. After being threshed, they are stored in estuarine water as described earlier. Direct seeding is feasible only in the upper half of the intertidal zone. Wave energies and other factors prevent successful establishment in the lower intertidal zone. Seedlings cannot be established everywhere that transplants can be established. Consequently, it is better to use transplants rather than seeds when time and money permit. On the other hand, if a large area is to be developed into a marsh within a limited time frame, the upper half of the inter- tidal zone could be seeded and trans- plants could be used in the lower half. Using both methods under favorable con- ditions, complete vegetative cover could be obtained just as quickly as with transplanting alone. Once established, will a smooth cordgrass marsh remain a smooth cord- grass marsh? A full appreciation of the interaction of tidal amplitude, salin- ity, duration of inundation, and sub- strate conditions is necessary to make such a determination. For smooth cord- grass to maintain itself, salinities around 20 ppt are necessary. If there are salinities of 5 ppt to 10 ppt, then in all probability smooth cordgrass will not remain dominant more than 3 or 4 yr. The marsh will be invaded by other spe- cies. This is not necessarily bad be- cause neither substrate stabilization nor marsh creation is being lost. If the purpose is to establish a marsh and to stabilize the substrate, smooth cord- grass is the best plant to use present- ly. If, on the other hand, a smooth cordgrass marsh is desired, planting in a low salinity area should not be done, or else planting should be restricted to a particular portion of the tidal re- gime. Only in the inundation zone that was covered the longest (11.5 hr) did smooth cordgrass dominate through the fourth growing season. All other zones were invaded by other marsh species. The invaders came in during the second growing season but did not become abun- dant until the third and fourth growing season. In summary, under a low salinity regime, the upper zones are inundated relatively infrequently and are invaded by other species which eventually out- compete and replace smooth cordgrass. Our marsh establishment methodology has been used to stabilize shorelines such as that near a residential develop- ment on the sound side of Bogue Banks, North Carolina. The shoreline had begun to erode because man had interfered with the system. About 10 yr before, a small boat channel was dredged about 100 m (330 ft) offshore and the material was deposited on a narrow fringe of existing marsh. The dredge spoil destroyed the marsh which had served as a buffer and protected the shoreline. There was no erosion problem until the marsh was de- stroyed. Erosion began shortly, and to combat it, a bulkhead was built, but it started to be undermined. The residents had heard about our work and asked if we could help them. We planted a zone of transplants about 12 m (39 ft) wide and seeded several smaller areas in prelimi- nary tests. By the end of the second growing season, we achieved stabiliza- tion with transplants, but the seeding attempts failed. I have described the use of trans- plants and seeding to establish a low, regularly flooded, smooth cordgrass salt marsh. I have described how to obtain plants by hand and mechanically and the relative man-hour costs for transplant- ing versus seeding. I have discussed the application of some of our findings. I do not have all the answers and the techniques that we have developed in North Carolina are not applicable every- where. Conditions in particular marshes should be studied and techniques that seem appropriate should be applied. In some areas wave energies are too great to achieve any measurable degree of suc- cess with vegetation, but where it can be used, vegetation is economically and ecologically feasible. In stabilizing estuarine shorelines, vegetation is in certain situations a logical alternative to man-made structures. LITERATURE CITED Woodhouse, W. W., Jr. 1979. Building marshes along the coasts of the continental United States. U.S. Army Corps Engin., Coastal Engin. Res. Cent., Ft. Bel voir, Virginia. Spec. Rep. 4. 96 pp. Woodhouse, W.W., Jr., E. D. Seneca, and S. W. Broome. 1972. Marsh build- ing with dredge spoil in North Car- olina. North Carolina State Univ. at Raleigh. Agric. Exp. Stn. Bull. 445. 28 p. Woodhouse, W. W., Jr., E. D. Seneca, and S. W. Broome. 1974. Propagation of Spartina alterniflora for sub- strate stabilization and salt marsh development. U.S. Army Corps Engin., Coastal Engin. Res. Cent., Ft. Bel voir, Virginia. Tech. Kemo. 46. 155 pp. Woodhouse, W. W., Jr., E. D. Seneca, and S. W. Broome. 1976. Propagation and use of Spartina alterniflora for shoreline erosion abatement. U.S. Army Corps Engin., Coastal Engin. Res. Cent., Ft. Bel voir, Virginia. Tech. Rep. 76-2. 72 pp. CREATION OF A SOUTHEASTERN UNITED STATES SALT MARSH ON DREDGED MATERIAL Robert J. Reimold Coastal Resources Division Georgia Department of Natural Resources 1200 Glynn Avenue Brunswick, Georgia 31520 THE SITE The Buttermilk Sound habitat devel- opment site is located in the Atlantic Intracoastal Waterway near the mouth of the South Altamaha River, Glynn County, Georgia (Figure 1). The site is a 2-ha (5-acre) disposal area representing 5 to 7 yr of dredged material disposal. The fringes of the area have already begun to generate creekbank Spartina alterni- flora marshes. Most of the area surrounding the site is made up of tidal salt marshes and small high ground hammocks, some of which are remains of dredged material disposal and rice farm diking. The soils of the area have been mapped as wet al- luvial land, tidal marsh, and "made land." Daily tidal inundations cause the surface layers of these marshes to build up very slowly by deposition; there is also a shifting of material caused by a strong tidal current. These strong tid- al currents create an average 2.1-m (6.9-ft) tidal regime that floods the marshes twice daily. The vegetation commonly found on the tidal marshes adjacent to the habi- tat development site is listed in Ta- ble 1. Spartina alterniflora is the most common species occurring on the lower elevations of the tidal marsh. Along the creekbanks where the tide inundates the plants twice daily, S. alterniflora grows to more than 2 m 77 ft] in height. When these plants die, the dead material is readily swept into the streams and nearby sounds where it is broken down into detritus. In marshes of slightly higher ele- vation, the common floral components include Spartina cynosuroides, Juncus roemerianus, Borrichia frutescens, and Scirpus robustus. The transition from the marsh to the high ground is often marked by a zone of herbaceous plants such as Distichl is spicata, Spartina patens, and Sporobolus virqinicus. Also scattered throughout this area are the shrubs Iva frutescens and Baccharis hal- imifol ia. In the transitional zone where the soil salinity is much higher, grow specialized plants adapted to this condition (e.g., Sal icornia virginica, Sal icornia biglovii , Batis maritima, and Limonium Nashii). The dredged material island, si ight- ly less than 2 ha (5 acres) along the southeastern edge of the Atlantic Intra- coastal Waterway, was used for the habitat development site. The grossly homogeneous sand substrate with an elevation of 3 m (10 ft) above mean sea level initially had very few resident plant species. Table 2 lists the vegeta- tion actually found on the site prior to its grading and preparation for a habi- tat development site. The areal cover- age of this vegetation was less than 1% of the total area. The substrate at the site prior to habitat development consisted of 99% quartz sand by weight and had no visible stratification. Some variation in grain size was noted, but the occurrence was random and thus not documentable. The limnic materials are indicative of the high energy system caused by the flow of the Altamaha River and the daily tidal movements. The sand had a very low re- sistance to deformation and rupture as evidenced by its constant manipulation resulting from current and wave action. Table 3 presents the physical analysis of cores taken from the development site prior to habitat creation. Table 4 provides a summary of the mineral content of the cores prior to 31°18' 81°22' Figure 1. Geographic location of the Buttermilk Sound marsh habitat creation site, Glynn County, Georgia. Table 1. Vegetation of marshes adjacent to the Buttermilk Sound habitat development site prior to grading. Scientific name Common name Acnida cannabinus Boltonia asteroides Cypress erythrorhizos Cyperus rotundus Eleocharis albida Eleusine indica Peltandra virginica Pluchea purpuracens Polygonum punctatum Pontederia cordata Sagittaria lancifolia Scirpus robustus Scirpus validus Sesbania exaltata Spartina al term" flora Typha domingensis Zizania aquatica Zizaniopsis mil iacea Tidemarsh water hemp Marsh boltonia Redroot cyperus Purple nutsedge Spikerush Goosegrass White arm Stinkweed Dotted smartweed Pickerel weed Bull tongue Saltmarsh bulrush Softstem bulrush Hemp sesbania Smooth cordgrass Southern cattail Wild rice Southern wild rice Table 2. Vegetation identified on the Buttermilk Sound habitat development site prior to grading. Scientific name Common name Acnida cannabinus Tidemarsh waterhemp Purple nutsedge Goosegrass Pickerel weed Hemp sesbania Smooth cordgrass Wild rice Cyperus rotundus Eleusine indica Pontederia cordata Sesbania exaltata Spartina alterniflora Zizania aquatica Table 3. Physical analysis of cores taken on Buttermilk Sound habitat development site prior to grading. Depth of core in cm pHwa Eh +Mv % H20 %0M CEC meq 0 - 25 6.9 410 16.4 0.07 0.91 25 - 60 7.0 390 17.7 0.07 0.89 0-25 6.9 420 20.0 0.13 0.28 25 - 60 7.1 410 21.8 0.13 0.28 0-25 7.0 410 16.4 0.13 0.85 25 - 60 7.0 380 19.1 0.13 0.49 0 - 25 6.9 350 18.2 0.07 0.44 25 - 60 7.1 400 18.5 0.07 0.48 0-25 6.9 420 18.6 0.20 1.22 25 - 60 6.8 410 20.0 0.13 0.91 0 - 25 7.0 400 17.3 0.13 0.59 25 - 60 7.0 409 19.0 0.07 0.45 a w pH = pH of soil and distilled water mixture; Eh = redox potential; %H 0 = percent water content of the core; % 0M = percent organic matter; CEC = cation exchange capacity = mil 1 iequivalents per 100 g (3.5 oz) . 10 S- o S- O- CD Q. 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CD #1 L0 +-> S- r- o ro 3 ro -C 3 ^ +-> Cl , — O 1 i — 3 1— o ro 00 JC •i — .^ +j +-> II c s- •T— o o +-> CO • 1 — 00 1 — II s- * 1 — CD c •r- ^3- 4-> o E O c i- CI- • 1 — o S- JC CD .- c a. cn •( — II O- oo E XJ CO 4-> CD S- 00 E •I 03 3 s_ CD a. s- o 1/1 o c»- 0) C JZ S- c t- Q. CD ro 00 Q. rjitJ O c CD JZ co ro l/l Q_ • 1 — E 00 oo CD i— >! II S- 03 a.+-> 03 c X o c > CD +-> 11 site preparation. The elevation was de- termined by the U.S. Geological Survey prior to site preparation. A level line from a U.S. Coast and Geodetic primary tidal bench mark in Darien, Georgia, was extended to the site. A temporary bench mark, established on high ground of ad- jacent Little St. Simons Island, was used to determine the elevation of the site. Subsequently, a tidal gage was in- stalled so that simultaneous comparisons could be made between the study area and the primary National Ocean Survey tide stations at Fort Pulaski, Georgia, and Mayport, Florida. METHODS Often it may be necessary to sup- plement the nutrient content of soils with commercial fertilizer applications so that marsh plants can become success- fully established. Marsh plant-soil in- teractions were evaluated in terms of carbon, nitrogen, and phosphorus levels to gain information about nutrient up- take by marsh plants and to determine marsh plant response to fertilizer ap- pl ication. The site was graded so that an ele- vation gradient was established from mean high water level to mean low water over a seaward distance of 60 m (200 ft), and 150 m (490 ft) horizontally. Within this intertidal area a series of research plots, each 1.5 by 3 m (5 by 10 ft), were established with a 0.7-m (2.3- ft) border between each plot. The variables included in the fac- torial design were (1) elevation: low (lower third of intertidal zone), middle (middle third of intertidal zone), and high (upper third of intertidal zone); (2) vegetation propagules: no propagule introduced except as naturally might oc- cur, or one of the following seven plant species: Borrichia frutescens, Distich- 1 is spicata, Iva frutescens, Juncus roe- merianus, Spartina a! terniflora, Spar- tina cynosuroides, and Spartina patens. These plants were all common inhabitats of natural marshes near the study area; (3) fertilizer treatment: no fertilizer, low level of inorganic fertilizer (122g/ m?), high level inorganic (244 g/m^), low level organic (33 g/m2), high level organic (66 g/m2).The inorganic fertil- izer was manufactured by Kaiser Agricul- tural Chemicals under the trade name of "Bounty". The analysis of the inor- ganic fertilizer was 10% nitrogen, 10% phosphorus, and 10% potash. The nitrogen components of that fertilizer included 3% nitrate-nitrogen from ammonium ni- trate and 7% ammoniacal nitrate. The organic fertilizer manufactured by Kerr- McGee Corporation and sold under the name of "Gro-tone" had an analysis of 16% nitrogen, 4% phosphorus, and 8% pot- ash with organic sources of nitrogen in the formulation; (4) types of propa- gules: sprigs and seeds. The sprigs were transplanted during June 1975 from marshes adjacent to the research plot. The seeds were collected from seed-pro- ducing plants adjacent to the research plot during the summer, fall, and winter of 1975 and were planted in April 1976 after appropriate winter cold treatment. Propagules were planted on 0.5-m (1.6- ft) centers in each of the test plots. Each of the above factors was randomized with three replicates. Consequently, there were a total of 720 test plots in the research area. Several parameters were measured to follow the success of the developing marsh. Analysis of the soil included mineral nutrients and physical analysis. The test plots were observed for the presence and abundance of macroinverte- brates and vertebrates. Fiddler crabs, snails, and other wildlife use of the area were observed and recorded begin- ning with the initiation of the project. The chemical analysis of the surrounding waters, as well as the interstitial wa- ter in the plots, was conducted through- out the project (Figures 2 and 3). Amounts of nitrogen and phosphorus in the water column appear to follow the typical estuarine pattern of high con- centrations in winter and low concentra- tions in summer. There has been no evi- dence of eutrophication from the fertil- izer added to the test plots. An analysis of the plants and their success in establishment was made. The remainder of the paper deals specifical- ly with the resultant plant growth of the sprigs transplanted June 1975 as an indicator of the success of the estab- lishment of the salt marsh. 12 3- mg/l 1- 0-1 BUTTERMILK SOUND WATER COLUMN TOTAL NITROGEN PARTICULATE NITROGEN ■NITRATE-NITRITE ■ AMMONIA-N — i 1 1 1 1 r— MAY JULY SEPT. NOV. JAN. FEB. 1975 1976 APRIL 200 m at N/L -150 -100 -50 -0 Figure 2. Nitrogen analysis of the water column surrounding the Buttermilk Sound marsh habi- tat creation site, May 1975 to April 1976. 13 .40- .30- mg/l .20- .10- 0- BUTTERMILK SOUND WATER COLUMN -O- TOTAL PHOSPHORUS -•- PARTICULATE PHOSPHORUS ORTHO PHOSPHATE j. ^ MAY JULY SEPT. NOV. JAN. FEB. APRIL 1975 1976 -12.5 -10.0 VQ at P/L 1-7.5 5.0 -2.5 J-o Figure 3. Phosphorus analysis of the water column surrounding the Buttermilk Sound marsh habitat creation site, May 1975 to April 1976. 14 Plants were identified by use of a small numbered plastic tag so that they could be recognized and quantified using nondestructive testing on a bimonthly basis. Plants were evaluated in terms of their condition, i.e., absent, dying, stable (stressed), stable, or new growth. In addition, the following parameters were assessed: height of the plant in centimeters, basal diameter in hun- dredths of millimeters, and number of live and dead leaves. The average live stem density and the number of flowering stems were also recorded. In addition to an assessment of the plants using the above created nondestructive technique, destructive sampling was initiated in November 1975 to assess belowground pro- duction of plant tissues. The destruc- tive sampling consisted of harvesting a 0.1-m (0.3-ft) subplot in each of the plots. Material from the aerial portion of the plant was dried to a constant weight in a force-draft oven at 100°C (212°F). Macroorganic matter, the bio- mass of plant tissue below ground, was defined as the tained on a 1- was assessed by soil from each depth where no was recovered, rial was also expressed on a quantity of material re- mm (0.04-inch) sieve and extracting the plant and 0.1-m2 (l-ft2) plot to a additional root material This macroorganic mate- dried and the dry weight g/m2 basis. RESULTS The data summarize results through April 1976 relative to the development of sprigs transplanted during June 1975. The results of biomass increases of the various plants are best summarized in Figures 4 through 10. Each of these figures depicts the average sprig height in centimeters (1 cm = 0.39 inch), stems per square meter (1 m2 = 10.8 ft2), aerial biomass (g/m2), and below- ground biomass of macroorganic material (g/m2) at time of transplant (June 1975) contrasted with the same parameters measured via destructive sampling in November 1975. 15 Borrichia frutescens JUNE 1975 CULM DENSITY 10/m2 AERIAL BIOMASS 9.8 g/m2 MOM BIOMASS 6.4 g/m2 NOVEMBER 1975 CULM DENSITY 12.7/m2 AERIAL BIOMASS 19.4 g/m2 MOM BIOMASS 15.7 g/m2 MOM - macroorganic matter Figure 4. Comparison of Borrichia frutescens plant vigor between transplantation (June 1975) and destructive sampling (November 1975). 16 Distichlis spicata 30 cm JUNE 1975 CULM DENSITY 10/m2 AERIAL BIOMASS 1.7 g/m2 MOM BIOMASS 2.3 g/m2 MOM - macroorganic matter NOVEMBER 1975 CULM DENSITY 142.3/m2 AERIAL BIOMASS 23.2 g/m2 MOM BIOMASS 15.7 g/m2 Figure 5. Comparison of Distichlis spicata plant vigor between transplantation (June 1975) and destructive sampling (November 1975). 17 Iva frutescens JUNE 1975 CULM DENSITY 10/m2 AERIAL BIOMASS 59.3 g/m2 MOM BIOMASS 20.5 g/m2 MOM • macroorganic matter NOVEMBER 1975 CULM DENSITY <10/m2 AERIAL BIOMASS 99.6 g/m2 MOM BIOMASS 49.6 g/m2 Figure 6. Comparison of Iva frutescens plant vigor between transplantation (June 1975) and destructive sampling (November 1975). 18 Juncus roemerianus 40 cm 30 cm 20 cm 10 cm -0 JUNE 1975 CULM DENSITY 10/m2 AERIAL BIOMASS 3.2 g/m2 MOM BIOMASS 4.3 g/m2 NOVEMBER 1975 CULM DENSITY 27.5/m2 AERIAL BIOMASS 5.0 g/m2 MOM BIOMASS 7.2 g/m2 MOM - macroorganic matter Figure 7. Comparison of Juncus roemerianus plant vigor between transplantation (June 1975) and destructive sampling (November 1975). 19 60 cm 50 cm Spartina alternif lora JUNE 1975 CULM DENSITY 10/m2 AERIAL BIOMASS 15.0 g/m2 MOM BIOMASS 12.0 g/m2 MOM - macroorganic matter NOVEMBER 1975 CULM DENSITY 97.7/m2 AERIAL BIOMASS 56.6 g/m2 MOM BIOMASS 119.0 g/m2 Figure 8. Comparison of Spartina alterniflora plant vigor between transplantation (June 1975) and destructive sampling (November 1975). 20 Spartina cynosuroides 40 cm JUNE 1975 CULM DENSITY 10/m2 AERIAL BIOMASS 5.5 g/m2 MOM BIOMASS 8.7 g/m2 MOM - macroorganic matter NOVEMBER 1975 CULM OENSITY 23.6/m2 AERIAL BIOMASS 15.2 g/m2 MOM BIOMASS 32.0 g/m2 Figure 9. Comparison of Spartina cynosuroides plant vigor between transplantation (June 1975) and destructive sampling (November 1975). 21 Spartina patens JUNE 1975 CULM DENSITY 10/m2 AERIAL BIOMASS 3.4 g/m2 MOM BIOMASS 3.1 g/m2 MOM ■ macroorganic matter NOVEMBER 1975 CULM DENSITY 321.5/m2 AERIAL BIOMASS 95.2 g/m2 MOM BIOMASS 49.9 g/m2 Figure 10. Comparison of Spartina patens plant vigor between transplantation (June 1975) and destructive sampling (November 1975). 22 TECHNIQUES FOR CREATING SALT MARSHES ALONG THE CALIFORNIA COAST Herbert L. Mason 1190 Sterling Avenue Berkeley, California 93306 Five or six researchers attempted to germinate Spartina on the West coast but could not find seed, and one of the investigators concluded that Spartina only reproduced vegetatively. Conse- quently, the U.S. Army Corps of Engi- neers requested that I plant a dredge spoil area and financed my efforts to learn how to propagate Spartina. I dis- covered a good key to locating Spartina seed. I looked for a patch that was in- fested with ergot because there had to be an embryo present before the ergot would become established. Our salt marshes are on mucky soils that are not consolidated uniformly over the whole area, so machinery could not be used. I believe machinery could be adapted to the mucky soils, but engineering facili- ties and continuity to the research re- sources were lacking. A harvest technique that proved very satisfactory required a team of two men in a boat, one with a pole, and the other with a pair of hedge pruning shears. The man with the pole pushed the plant over the boat, and the other man snipped off the seed heads. In 2 days, we harvested enough seed to fill three 55-gal (208-liter) drums. By accident I discovered how to store these seeds. I just looked at the situation and said, "Well, these drop into the water so they must require water"--and so we transferred them to gallon jars and put them in the refrig- erator. After about a month, I decided to flush the seeds because they smelled bad. We took the seeds out every 2 or 3 weeks, flushed the old water out, and put in fresh water. Then I noticed that the seeds were germinating in the refrigerator about March. I examined the Salicornia seed that we had saved the same way and it was also germinat- ing. We tried many fertilizers and different methods of achieving germina- tion. We discovered that there was some germination right in the spikes. Some of the seeds were bright green with the radical already showing on the seeds and these germinated immediately. There is a differential of germination that is characteristic of the seed. Some of the Spartina germinated immediately. A few weeks later a few more germinated and this continued until March when the rest came up. If all plants in arid regions germinated at once with the first rain, the history of vegetation would be one of extinction. I suspect that is also true with aquatic plants. We also tried cuttings and based our efforts on the experience of people on the East coast. Some people say that our cordgrass is also S_^ al term" flora but we learned from experience that it makes no difference; the least important thing about a plant is its name. There is enough variation within a given species so that similar techniques do not quarantee success. We made cuttings from the rhizomes and fall buds and had good success with both. In the long run, it did not make much difference whether we used rhizomes or fall buds. But our problems with salt marsh construction are of three types: (1) areas that were reclaimed in San Fran- cisco Bay that had approximately 97% of the original salt marsh destroyed by diking; (2) some beautiful marshes outside of these dikes that have come in since the diking. We can learn a lot about the recovery of marshes by study- ing these areas; and (3) land that not much has happened to; it has only been used for grazing. In the latter case we can remove the dike and let nature take its course. But the first example is a very serious problem. I doubt if the 23 marsh can be flooded immediately and be expected to revert to salt marsh. It will not do it! The salinity is too high; it will take a long time for the salt to be leached out. Some experimen- tal work manipulating the soil will be needed. The Army Engineers would like to fill such marshes with dredge spoil. However, there is more than one dredge spoil problem in the San Francisco Bay area. I can show dredge spoil that was laid down in 1952; by 1973 it still was bare soil. It takes a long time before the salts in those soils will leach out and vegetation will grow. There is another phase-actually planting dredge spoil. We learned that with time the spoil will consolidate and machinery can be taken in. First, we did everything by hand because we could not use machinery. We prepared a seed bed, fertilized some, and did not fertilize others. We used different kinds of fertilizers; and most interesting are the areas showing the best growth 3 yr after fertilization. We have not fer- tilized since then because we did not think it is necessary; the plants are doing fairly well. The first year they did not look very well, but the second year they were growing fairly well, and the third year I was amazed to see the results. Some of the single bud cuttings had 14 or 15 shoots coming up. However, it was very discouraging the first year. The plants stayed alive, but they did not grow much. Our best luck was in the lower tid- al areas. We got very good establish- ment beyond the area of the low-low tide and the high-low tide. We got a little established above that but not very con- clusive results. These results alone suggest that we are dealing with a ge- netically different situation with the plants. 24 SALT MARSH CREATION IN THE PACIFIC NORTHWEST: CRITERIA, PLANTING TECHNIQUES, AND COSTS Wilbur E. Ternyik Wave Beach Grass Nursery Post Office Box 1190 Florence, Oregon 97439 INTRODUCTION Wave Beach Grass Nursery contracted with the Corps of Engineers Waterways Experiment Station at Vicksburg, Missis- sippi, to provide a report of basic data collected through one growing season on pilot test planting of six species of vascular plants endemic to the area at Miller Sands. This island complex under tidal influence is located near River Kilometer 39 (River Mile 24) on the low- er Columbia River, Oregon. This report outlines the progress of the pilot test from plant selection, collection, plant- ing, and growing season from 21 June 1975 through 18 November 1975. Although my experience with marsh plantings is limited, I have worked with plant mate- rials and in the erosion control field on the Pacific coast for 34 yr. METHODS The geographic location of Miller Sands is 9.7 km (6 mi) from Tongue Point on the eastern edge of the city of As- toria, Oregon. The test site was created in June 1974 by the Corps of Engineers' placement of 612,000 m3 (800,000 yd3) of dredged material. Particular size analy- sis shows basically sandy materials ranging from 2.8 to 3 mm (Oregon State University, 75 samples). The lower 9 m (30 ft) of the site is not of dredged materials, but contains long-term accu- mulated sediments of very fine silt and wood particles. Plants were selected because of availability of uniform stock sufficient to plant both plots of the species. Plants were selected as near to the early growth stage as possible to avoid possible shock of excessive topping. Species selected for planting were Eleocharis palustris, Juncus balticus, 6. The for Juncus effusus, Scirpus validus, Carex lyngbyei, and Deschampsia caespitosa. Sites for plant collection were se- lected with the following factors in mind: 1. Quality and vigor of plants present on site; 2. State of growth, both top growth and root system; 3. Location in relation to dis- tance from site; 4. Age of plant that would mini- mize the need for extensive cleaning; 5. Quantity of plant stock growing on site in order to avoid de- pletion problems; Stands growing in sandy areas similar to the planting test plot. collection procedure was the same for all species. All plants were hand dug by shovel, and sand was cleaned from the roots by dipping them in water. The sprigging method was used because of the time factor resulting from the late- season start. All plants were topped to a uniform height before digging to provide surface integrity to the entire plot. Failure to observe this procedure may have resulted in tidal currents washing out areas extending above the general plant surface height and result- ed in a progressive failure of the en- tire planting. The rhizome or root length was a personal judgment of what would constitute a transplant of suffi- cient size to allow for expected top growth recovery and new feeder root es- tablishment. Lengths of the root cut- tings were generally made with a section of rhizome containing from one to three culms or stems. Pruning of feeder root systems was not necessary. Two methods of plant material stor- age were attempted, but one method was 25 quickly discarded. The initial method was to heel-in prepared plants in sandy intertidal areas. However, the heeled-in plants, after one tide, were so firmly settled that it became a major job to redig them; and major damage occurred in the second removal operation. The second method was storage in plastic containers placed in the intertidal marsh areas that provided shade. Even more important was the twice-a-day covering of the plants by the tide, which prevented ex- cessive drying. All plants were planted either the same day or within 24 hr after digging, weather permitting. During storage trials, some plants were stored up to 5 days without any problems. The Corps of Engineers predetermined that plants were to be placed at an elevation rang- ing from +0.50 MLIW to +6.0 MLLW. Length of plots varied as did the number of plantings per plot. Because of even, flat terrain at the site and uniform sand material, no site preparation, such as plowing, disking, harrowing, or rak- ing, was necessary. On an intertidal sandy site of this type, I believe any advanced agitation of the material would cause negative results when trying to firm the plant at time of planting. Also, tidal erosion could be increased and the sediment transport rate accel- erated. Fertilized and unfertilized plots followed the same layout design, plant- ing depth, and plant height. Table 1 gives the spacing, planting depth, and culms per planting stock for species planted in this test. The initial fertilizer selection for the pilot test was made with maximum root growth and minimum culm and leaf growth in mind. The fertilized plots all received a single hand broadcast appli- cation of Elephant brand 11-55-0 pellet- ed fertilizer at the rate of 100 kg/ha (90 lb/acre). Second year application should promote culm and leaf growth and reproduction. Ammonia-based fertilizers may cause severe problems with the la- goon fisheries. According to Ted Blahm, National Marine Fisheries Service, the entire lagoon, now highly productive, could suffer if this problem is not solved. The possibilities of creating new or better marsh habitats are only a short time away. We are about 2 yr away from developing accurate cost figures for large scale plantings. This will depend on further results from research now underway on plant selection, ferti- lizer rates, density, and spacing. Equipment is now available that, with some modification, can be used for planting on upper elevations of the intertidal areas with conditions simi- lar to Miller Sands. This equipment is capable of planting 180,000 plants per day during good weather. Cost per hec- tare will drop sharply with machine planting. The future will see marsh estab- lishment not only on existing spoils, but also on carefully selected mainte- nance dredging disposal sites. Island sites could be created as new feeding and nesting areas for wildlife to help replace those lost to shoreline develop- ment. Marsh creation could also be used as an environmental trade-off to help enhance waterfowl and fishery habitat of any wetland area. 26 Table 1. Spacing, planting depth, and mean number of culms per planting stock for species used in the study. Species Spacing (cm) Planting depth (cm) Cul plan ms per ting stock Eleocharis palustris 50 8 3 Juncus balticus 50 8-10 8 Juncus effusus 50 10 7 Scirpus validus 50 10 3 Carex lyngbyei 50 10-13 3 Deschampsia caespitosa 50 10-13 7 27 SALT MARSH SOIL DEVELOPMENT John L. Gallagher College of Marine Studies University of Delaware Lewes, Delaware 19958 Salt marsh creation may be consid- ered to be basically a problem of devel- oping salt marsh soils from marine sedi- ments. First, it must be decided what a marsh soil is and how it develops. Sec- ond, must be determined what character- istics of the original sediment (i.e., dredged material) are especially impor- tant in enabling us to predict whether it might be easily transformed into a salt marsh soil. Third, the natural system to select plants which may facil- itate the desired changes in the sub- strate must be examined. The concept of soil depends on the viewpoint of the investigator. Since our concern is in creating coastal eco- systems and a major step is getting vegetation to grow on the substrates, our viewpoint is edaphical. Sediments from which natural marshes develop are tidally deposited resulting in rather uniform grain size fractionation. Dredg- ing is the usual method of deposition of sediments for marshes created artifical- ly on the coast. This technique leads to complex and variable parent material, making the establishment of proper con- ditions for plant growth difficult. Re- gardless of the method of deposition, the objective is to duplicate the nat- ural anatomy of soil which takes the form of a profile changing with depth. Numerous soil formation processes (Table 1) interact to develop the anatomy which reflects both the parent material and the environment. The original variable mixture of minerals will have organic matter added by plant, animal, and microbial activity (humification). In some cases, dredged material will already be rich in organic material. The amount of air and water in the soil will depend on sediment grain size, elevation relative to the tides, and soil structure. Depending on the salinity of the tidal water and fre- quency of inundation, salinization may be a major process in determining the final nature of the soil. Structure is often minimal in marsh soils because of sodium saturation of the cation exchange capacity. These puddled conditions re- duce drainage, resulting in even more poorly drained soils than occur at simi- lar nonsaline sites. Anaerobiosis in the waterlogged soils results in gleiza- tion. Soils are classified by a method similar to the classification of plants and animals, (i.e., orders, suborders, great groups, subgroups, families, and series). From profile descriptions, the taxonomic position of the soil may be determined. Most marsh soils fall into one of two orders. Those which are pri- marily organic are Histosols. In the coastal areas where sulfates from sea- water are reduced to sulfides, the soils are called Sulfihemists. The other order of soils represented in the marsh are the Entisols (recently formed mineral soils). Within that group, the Sulfa- quents are common salt marsh soils. The description in Table 2 of the Capers Series is typical of many marsh soils along the southeast Atlantic coast of the U.S. Table 3 contains a description of a typical marsh soil from a sandy Georgia marsh. There is no "0" horizon of partially decayed organic matter in many southern marshes. The combination of tidal flushing and rapid litter turn- over interacts to reduce organic matter accumulation in the most hydrological ly active marshes. An "0" horizon at the top is much more common in the northern latitudes, e.g., in Maine, and along the Pacific Northwest coast. These organic layers develop where decay is not as rapid as it is in the south. There is a series of other horizons, A, B, and C, which are basically mineral horizons. "B" ho- rizons are not frequently seen in salt marsh soils. Usually in southern salt ?R Table 1. Some processes of soil formation. Name Process Eluviation - Movement of material out of a portion of a soil profile. Important in forming the "B" horizon. Illuviation - Movement of material into a portion of a profile. Salinization - The accumulation of soluble salts such as sulfates and chlorides of calcium, magnesium, sodium and potassium in salty (salic) horizons. Alkalization - The accumulation of sodium ions on the exchange sites in a soi 1 . Humification - The transformation of raw organic material into humus. Gleization - The reduction of iron under anaerobic soil conditions, with the production of bluish to greenish gray matrix colors, with or without concretions of yellowish, brown or black concretions. Podzolization - The migration of aluminum, iron and organic matter from a horizon. Laterization - Movement of silica out of the horizon with accumulation of iron oxides. 29 Table 2. Description of Capers Series marsh soil from Chatham County, Georgia (described by R. W. Wilkes). CAPERS SERIES The Capers series is a member of fine, mixed, nonacid, thermic family of Typic Sulfaquents. These soils have very dark clay loam "A" horizons over dark gray and greenish gray clay "C" horizons. They are saturated continuously with saltwater. Typifying Pedons : Capers clay loam - idle. (Colors are for moist soil unless otherwise stated.) All — 0- 8" Very dark gray (10YR 3/1) clay loam; weak fine subangular blocky structure to massive; very sticky; many large pithy fibrous roots; common small clam shells on surface; neutral; gradual wavy boundary. (4 to 10 inches thick) A12g — 8-19" Very dark gray (10YR 3/1) and black (10YR 2/1) clay loam; massive; sticky; many large fibrous roots; neutral; clear waxy boundary. (10 to 20 inches thick) Clg — 19-33" Dark gray (10YR 4/1) clay; massive; sticky, when squeezed in the hand soil flows between the fingers with some dif- ficulty; many fine roots; neutral; gradual wavy boundary. (8 to 16 inches thick) C2g -- 33-50" Greenish gray (5GY 5/1) clay; massive; sticky, when squeezed in the hand soil flows between the fingers with some difficulty; few fine roots; mildly alkaline; gradual wavy boundary. (6 to 18 inches thick) C3g -- 50-60" Greenish gray (5GY 5/1) silty clay; massive; sticky, when squeezed in the hand soil flows between the fingers with some difficulty; few fine roots; mildly alkaline. 30 to IS 03 cr > 03 o u oo IT3 o to CU o a. u a oo cu 03 10 p-. r^ O in • ■ to E 3 o o -i. O s_ i— s_ V V (O i— .o E ro •!- cu cu CU E 4- * =1 3 C£ to i/> 1 — (^ ai +-> OS > a> •■- o 1 4- i— s_ zz z CU o s- s= 3 CU +-> +J Oo5 m 3 •!- S_ to -m c CO O U >> ■ — s_ 03 03 3 ■D -o >- c 03 > 3 S- (O O O) 3 CO OO a: • Q. r». 03 ■o >, 03 > S- 03 Cn 3 r-- o v CD 3 03 > I S- «3 >> CU > t— • T3 O O O i— S_ V ro i/l CU E 3 3 1/1 O t— S- 03 3 .a > CD s- o o C_) C E o <_> N — ■ , s r— r~~ S- -C i O +-> i— o i: o. <--- a> X} -a at c ■r* 03 S- cn cu i— cu CD to C O •i- o to i — cu c 1 — 03 s_ Dl CD CU CD IT) C o r— o l/> r-. CO cu T3 , — CU -O. tz 03 •r— •i — 03 S- S- 4- CD cu cu > i— CU • r- en to 10 c o to •r- O 03 to i — E cu c c •r- 3 in E O cu O S- ^ S~ JD +-> Q. +-> SZ o CU to s: C •!- i- 3 4- o ^— 3 r- CU cu 4- >> cu S- 3 CU XI +-> c c X •i- OS cu 4- to -a >, c CU 03 r- 3 E *" E O O) 3 s_ -a •r- .O. C +-> TJ 03 -C CU 4-> C7> E C 00 -i- t— c c tr> r— o •>- +-> E E CC c cc E O >- -r- >- O S- O 03 O O D_r— 4- ,— CU T3 C C •r- 03 4- CO CU c •1— c: E 3 o o 5- 5- Q.JD CU -C cn on kD 5- •i — ** rc> 3 LO i — O i — or 3 r— >- CU CU c 4- >5 i — 03 to >- E UO >, 03 to 03 O 4-> i. i— CU >, C7I -* 03 >>T3 (J 5- J^ -O C O O) S_ C 03 Q. 03 03 CO 4- T3 to r- O >> >— T3^ E 03 to C i — 03 E +-> o3 ^ O tO CU <5f I 3 o ■— >- -o CU O ~~-.LT) C 4- D-LT) 03 T3 >, E C 03 03 OS r— O to U p— 10 C\J C CO 3 o >- S- uo J3 • CM cn 03 •i- s- r— O) c CO 3 O a: S- S- J3 o 1 — ■ 4-> sz >- cn 10 •r— s_ " — cn >- 03 S- >- cn 03 S- ■— ^i o>^» tO r— to *'— "~~». +-> C LO ^z ai CU cn>- cu >- •i- O S- CD r— r— COLD CM OO Ol I t— r-~ C_)— ' o CO enevj CM CO (_) — cn CO o 31 marsh soil, the transition is from an "A" horizon, where the organic matter degraded into small particles and to humus, right into a "C" horizon, where the material has not been affected very much by processes of soil formation. In some sections of the country, the Soil Conservation Service is mapping salt marshes by soil types which will help characterize soils in local situations. If descriptions of the various soils that occur in your area are available, this can serve as a reference source to indicate how far along the process of soil formation is in a marsh. More com- plete discussions of soils in general may be found in Buol et al. (1973) and Brady (1974). Salt marsh soils are less thoroughly understood than upland soils, but a literature is developing (Cotnoir 1974; Coultas and Calhoun 1976; Gallag- her et al., 1977; Coultas 1978). The problems associated with the development of salt marsh soils from ma- rine sediments are in one of five cate- gories: stability, acidity, moisture, salinity, and nutrients. These can be considered separately, although it is clear they interact and depend to some degree on one another. Without stability the other factors do not matter. Salin- ity may reduce soil structure and de- crease stability. Similarly, high mois- ture conditions may decrease stability by increasing the flow characteristics of the soil. Of concern is the ability of the material to be confined until such time that roots of the marsh plants can add to substrate stability. Through the Dredged Material Research Program, the U.S. Army Engineer Waterways Experi- ment Station in Vicksburg, Mississippi, has produced a large amount of litera- ture about techniques for protecting dredged material from erosion and meth- ods for stabilizing it. A second problem is acidity. The Dutch recognized this problem in their acid meadow soils called Katterklei, re- ferred to as "cat clays" in this coun- try. The extreme acidity, which may be as low as pH 2, arises as the conse- quence of a series of reactions begin- ning with the accumulation of sulfides which are produced by the reduction of sulfates from seawater. The resulting iron polysul fides in the sediments cause no acidity problems until the sediments are exposed to oxygenated conditions where iron sulfate and sulfuric acid are formed. The acid yield depends on the ratio of iron to sulfur, as well as the total amount present. This cat clay sit- uation arises in marsh creation sites where the sediment is placed high in the intertidal zone with the objective of producing a transitional zone marsh (the high marsh area which grades into up- land). Effects of low pH on the plants may be direct or indirect through its influence on soil ion balance. Tied closely to the cat clay problem is that of soil moisture since the degree of waterlogging determines the oxygenation of the soils. The soil moisture situation in- volves both the degree of saturation and the periodicity of various moisture re- gimes. The lower elevation salt marsh soils are usually near saturation much of the time. The anaerobic conditions, coupled with salinity, play a major role in the zonation seen in marshes. Much effort has been directed toward under- standing the environmental factors in- volved in controlling the distribution of salt marsh plants over the last 75 yr. A brief discussion of zonation in wetlands can be found in Gallagher (1977). Soil salinity is influenced by five factors. The first is the salinity of the estuarine water flooding the marsh. The second factor is elevation relative to the intertidal zone. Evapotranspira- tion from the marsh results in water loss and accumulation of salt. Low in the intertidal zone where flooding is frequent and soil water circulation rel- atively great, soil salinity is similar to that of the estuarine water. At higher elevations in the marsh where water circulation is reduced, salinities are increased. Near the marsh fringe, salinities again drop as the relative influence of rainfall to salt water in- creases. The third factor in determining the soil salinities is the environmental complex; temperature, pan evaporation, and rainfall all interact to influence water balance in the marsh. A fourth factor is soil texture. Coarser textured soils are generally more responsive to flushing by rainfall and tidal waters. 32 Finally, the species of plants nay in- fluence evapotranspiration through their productivity and water-use efficiency. The last category associated with developing soils from marine sediments is the ability of the substrate to sup- ply nutrients. Coarse sands will gen- erally be lower in nutrients than finer textured substrates. Sandy marshes in North Carolina have been shown to re- spond to additions of N and P (see E.D. Seneca - "Techniques for Creating Salt Marshes along the East Coast" in another section of this proceedings). Similarly, marshes in Georgia (Gallagher 1975), Delaware (Sullivan and Daiber 1974), Massachusetts (Valiela and Teal 1974), and Oregon (Gallagher unpublished) have responded to nitrogen applications. Given these soil problems, there are certain plants (occurring in the natural marsh) that have characteristics which may make them useful in facilitat- ing certain desired changes in the sub- strate. These plants are generally not tested experimentally in artifically created marshes; nor has the plasticity of the characteristics to environmental conditions been evaluated. In the ab- sence of such experimentally tested information, consideration of plant characteristics may help the manager to plan his research needs. Sporobolus virginicus, Distichlis spicata, and Salicornia virginica are tolerant of a wide range of salinities. Spartina patens is adaptable to growth in the upper marsh and also in drier areas which might be found in the upper levels of dredged material deposits. There are several recommendations for managers who are looking for plants of different rooting depths. The depth of roots may be important for stabiliz- ing soils or for preventing roots from penetrating a soil zone which is inhos- pitable or may contain a contaminant that could be translocated to aerial food webs. The following recommenda- tions are applicable to the southeast and to some extent to the mid-Atlantic States. Sal icornia and Sporobolus are typically shallow rooted. High marsh Spartina alterniflora, Distichlis spi- cata, and Spartina patens grow to inter- mediate depths. Low marsh Spartina alterniflora, Juncus roemerianus, J. gerardi, and Phragmites communis grow fairly deep. If the goal is to increase soil leaching, Distichlis spicata, Spar- tina patens, and Sporobolus virginicus are good choices. These same species have high root: shoot ratios that favor quick stabilization. If the plant characteristics are not known, an aluminum irrigation pipe corer can be used to sample root systems (Gallagher 1974). This information may help in selection of the proper plant to bring about the desired change in the substrate. LITERATURE CITED Brady, N.C. 1974. The nature and prop- erty of soils. Macmillan Publish- ing Co., Inc., New York. 639 pp. Buol, S.W., F.D. Hale, and R.J. Soil genesis and Iowa State Univ. pp. Marsh soil of the Pages 441-448 j_n W. H. Queen, eds. halophytes. Academic New York. soils of the Rookery Bay, Soc. Am. J. McCracken. 1973. classification. Press, Ames. 360 Cotnoir, L. J. 1974. Atlantic coast. R. J. Reimold and Ecology of Press, Inc. Coultas, C.L. 1978. The intertidal zone of Florida. Soil Sci. 42:111-115. Coultas, C. L., and F. G. Calhoun. 1976. Properties of some tidal marsh soils of Florida. Soil Sci. Soc. Am. J. 40:72-76. Gallagher, J. L. 1974. Sampling macro- organic profiles in salt marsh plant root zones. Soil Sci. Soc. Proc. 38: 154-155. Gallagher, J. L. 1975. Effects of am- monium nitrate pulse on the growth and elemental composition of natu- ral stands of Spartina alterniflora and 62 Juncus roemerianus. Am. J. Bot. 644-648. Gallagher, J.L. 1977. Zonation of wet- lands and tidelands. Pages 752-758 in J. R. Clark, ed. Coastal ecosys- tem management: a technical manual for the conservation of coastal re- sources. John Wiley and Sons, New York. 928 pp. Gallagher, J. L., F. G. Plumley, and P.L. Wolf. 1977. Underground bio- mass dynamics and substrate selec- tive properties of Atlantic coastal salt marsh plants. Army Corps 33 Engin., Waterways Experiment Sta- fertilizer. Ches. Sci. 15: 121-123. tion, Vicksburg, Mississippi. Valiela, I., and J. M. Teal. 1974. Nu- 131 pp. trient limitation in salt marsh Sullivan, M. J., and F. C. Daiber. 1974. vegetation. Pages 547-563 in R. Response in production of cord J. Reimold and W. H. Queen, eds. grass, Spartina alterni flora, to Ecology of halophytes. Academic inorganic nitrogen and phosphorus Press, Inc., New York. 34 SALT MARSH SUBSTRATE INTERACTION: MICROORGANISMS Roger B. Hanson Skidaway Institute of Oceanography Savannah, Georgia 31406 INTRODUCTION Odum (1971) described several ideas of ecological succession, and a summary of those characteristics describing com- munity development are presented in Ta- ble 1. The creation of a coastal ecosys- tem from dredged materials will begin with an orderly process in community de- velopment. The succession in the commun- ity will proceed from an unstable low biomass environment and eventually cul- minate in a stable high biomass ecosys- tem. In the early stages of community succession, the rate of primary produc- tion will generally exceed the rate of community respiration. However, as de- velopment proceeds, the ratio of primary production to community respiration will approach one. But, when production ex- ceeds respiration, organic matter and biomass will accumulate in the ecosystem and the resulting production to biomass ratio will decrease. As the ecosystem develops further, organisms will be linked together in a relatively simple linear food web. Pri- mary production will initially support the microheterotrophs (bacteria, yeast, and protozoans) by supplying the neces- sary organic carbon, and the meiofauna and macrofauna will graze on the micro- heterotrophs. As the system matures, the food web will become more complex and the system will switch from a graz- ing food web to a detrital food web, typified by the marshes in Georgia. This brief review of ecosystem development emphasizes the flow of energy from the primary producers to the secondary pro- ducers. The goal of community develop- ment is to increase stability within the ecosystem and to achieve a large and di- verse population of organisms. Under- standing the succession of benthic com- munity development and production rates of various populations in dredged mate- rials will greatly increase our knowl- edge of coastal ecosystems. In these proceedings several inves- tigations have reported on the estab- lishment of rooted aquatic plants within wetland areas and dredged materials. There have been only two reports about invasion and colonization of dredged ma- terials (Garbisch et al. 1975; Cammen 1976b) by macrobenthos, and there has been no report that dealt with microbial development in dredged materials. The gap in the flow of energy between pri- mary producers and macroinvertebrates requires investigation. In addition, there has been no report on the impor- tance of microbial populations in higher plant establishment in dredged materi- als. Therefore, information on microbial development in dredged materials is des- perately needed so that comprehensive guidelines can be formulated for coastal ecosystem habitat development. METHODS SAMPLING SITE Microbial colonization in dredged materials planted with marsh plants was investigated at Buttermilk Sound, Geor- gia, and was supported by the U.S. Corps of Engineers, contract to Dr. Robert Reimold. Data were collected between January and September 1976. AERIAL VIEW OF SITE Buttermilk Sound Habitat Develop- ment Site (BSHDS) is shown in Figure 1. The dredged material (elevation 2.4 m or 8 ft)was graded on the eastern side of the island from mean low water (MLW) to mean high water (MHW). The site 5 mo later showed considerable deposition of sediment (clay and silt) and organic de- bris above MLW (Figure 2). Below MLW, sand waves were quite evident, indicat- ing high energy water movement. The MLW zone was very unstable, and the movement of sand in the northern section of the 35 Table 1. Characteristics of community development. Community variable Ecological succession Early stages Late stages Community energetics Primary production to community respiration Production to standing crop biomass Food chain > 1 - 1 Low High Grazing Detritus Community structure Total organic matter Species diversity Small Low Large High Nutrient cycl ing Mineral cycle Open Closed Homeostasis Stability Poor Good 36 Figure 1. Aerial photograph of the Buttermilk Sound Habitat Development Site (BSHDS) a few months after grading from mean low water to mean high water. BSHDS is center left of photograph and is located at eastern side of the Intercoastal Waterway (not shown). 37 Figure 2. Aerial photograph of BSHDS approximately 5 months after the photograph shown in Figure 1. The very dark area, center right, is due to detritus build-up on the site. Sand waves are seen at the far right hand side of photograph. 38 site formed a sandy shoal in the Inter- coastal Waterway. The site was divided into three replicate blocks covering the three tidal zones (upper, middle, and lower thirds). Within each block and tidal zone the blocks were further sub- divided into 90 plots which were either planted with marsh plants, sprigs, or seeds, or fertilized with various amounts of organic or inorganic ferti- lizers. Each plot was bordered by a 0.5-m (1.6-ft) wide pathway for access to the plots (Figure 3). For practical reasons, the microbi- ology was done on two planted areas, sprigged with either Spartina alterni- flora (SA) or Spartina patens (SP), and a nonpl anted (NP) area within each rep- licate-tidal block. The random location of SA, SP, and NP plots within each block is shown in Figure 4. MICROBIAL BIOMASS Adenosine triphosphate (ATP) stand- ing stocks in planted and nonplanted plots were measured over time and at various depths (Bancroft et al. 1976). In addition, bacterial biomass was esti- mated by plate counts on Difco 2216 Ma- rine Agar, and the plates were incubated aerobically and anerobically. Yeast biomass was estimated by planting on Sabouraud Dextrose Agar (2% NaCl). Ben- thic algae, diatoms, and protozoans were followed qualitatively (microscopically) by noting which genera were present. RESULTS AND DISCUSSION ATP BIOMASS Seasonal variation of ATP biomass with depth in 27 plots (NP, SA, and SP) is shown in Figures 5, 6, and 7. From January to about July, the concentration of ATP increased in the surface stratum but ATP concentrations remained un- changed in the 5- to 7-cm and 10- to 12-cm (2- to 2.8-inch and 4- to 4.7- inch) strata. The decrease in ATP bio- mass with depth suggests that the carbon input is from the surface and the source of carbon may be from the detrital and algal carbon deposited on the surface. Unfortunately, data are not avail- able on microbial development at other dredged material sites. However, for comparison with other coastal systems, the ATP biomass found at Buttermilk Sound was 20 times lower than microbial biomass reported by R.L. Ferguson and M.B. Murdock working in subtidal estua- rine sands in the Newport River estuary, North Carolina. Christian et al. (1975) working in the Spartina marshes contig- uous to Sapelo Island, Georgia, reported microbial ATP biomass 50 times higher than the concentration measured at But- termilk Sound. These differences are not surprising because the habitat at But- termilk Sound is in its early stages of development. The biomass may have had an effect on the initial establishment of marsh plants in dredged materials, but that hypothesis is unlikely when one consid- ers the ATP biomass similarity in the NP, SP, and SA plots. The opposite is also possible, i.e., plant growth is not influencing microbial ATP biomass in the sediment, at least in the early stages of development. Since there was no plant-microbial biomass correlation, and biomass was similar in planted and nonplanted plots, detritus deposition may be one of the most important factors in the carbon en- richment of coastal systems. Detritus is defined as silt and clay (abiogenic origin) and organic matter (biogenic or- igin). Thus, given suitable time, the course sands at Buttermilk Sound will be filled in with smaller particles which will hold a larger microbial flora. In addition, the detritus deposited on the site probably contained attached micro- organisms. In the estuary, 80%-90% of the bacteria are attached to detrital particles larger than 14 micron and few are free in the water (Hanson and Wiebe 1977). Cammen (1976a), working with dredged materials near Drum Inlet, North Carolina, reported an accumulation of organic matter at an annual rate of 80 to 100 gC/m2 for the top 13 cm (5 inches). Therefore, microbial biomass will be increasing with detrital build up at BSHDS. BACTERIAL BIOMASS The bacterial populations (aerobic and anaerobic) in dredged materials were 39 Figure 3. Close-up view of one plot sprigged with Spartina alterniflora. The dark foreground is due to detritus deposition. Interstitial water well is seen in the center of the plot. Each plot is spaced apart by a 0.5-m border. 40 Upper Third Middle Third Lower Third Replicate no. BUTTERMILK SOUND HABITAT DEVELOPMENT SITE SA NP NP SP NP SA SP SP SA SA SP NP SA SA SP NA NP SP SP SA SP SA NP SP SA NP NP -MHW MLW N Figure 4. Diagrammatic location of the Spartina altemiflora (SA) and Spartina patens (SP) and nonplanted (NP) plots at BSHDS within each block and tidal zone. 41 Sporting alterniflora * ■D o o 3 1.4 1.2 Upper • 0-2 cm r 05-7 AI0-I2 1.0 0.8 06 0.4 ^Lx*^ J_ -L ^ 0.2 ie^==12B===S;a-=^s=^S=^-^ 1.4 Lower 1.2 1.0 » 0.8 j / 0.6 / . 0.4 / 0.2 W-""^'*^ ~-*^r- & 2* JAN FEB MAR APR MAY JUNE JULY AUG SEPT Figure 5. Microbial biomass (ATP) in the sprigged Spartina alterniflora plots in the uppt middle, and lower tidal zones. Seasonal ATP concentrations were measured at three depths: •, 0-2 cm;0, 5-7 cm; and A, 10-12 cm. The ATP values for each block within each tidal zone were pooled together and the mean ±SE plotted. 42 Sporting patens "a> >> ■ o u a. \- < 3 Upper Third • 0-2 cm O 5-7 A 10-12 1.4 1.2 " Middle Third 1.0 T" ^T 0.8 - -p / 0.6 - 0.4 0.2 Lower Third JAN FEB MAR APR MAY JUNE JULY AUG SEPT Figure 6. Microbial biomass (ATP) in the sprigged Spartina patens plots. See Figure 5 for details. 43 No Plants 1.4 1.2 " Upper _,. •0-2 cm 0 5-7 /\ A 10-12 1.0 0.8 0.6 f 0.4 0.2 -•g^-es— egsss^A-s&o^ — i — fe=^?r=e-A Lower * >> i_ ■o T O o a. \- < 3 14 1.2 1.0 0.8 0.6 04 0.2 JAN FEB MAR APR MAY JUNE JULY AUG SEPT Figure 7. Microbial biomass (ATP) in nonplanted plots. See Figure 5 for details. 44 investigated over time in relation to the planted and nonplanted plots in the mid-tide zone. Figures 8, 9, and 10 show the bacterial populations between Janu- ary and September for NP, SA, and SP plots at three depths. In the surface stratum, the bacterial populations were generally greater than 5 X 10^ colony forming units (CFU) per gram dry weight. The populations were generally an order of magnitude lower in the substrata than in the surface stratum. The dredged materials at Buttermilk Sound were essentially aerobic in Janu- ary 1976. During the later part of the year, black iron sulphide zones were noticed in the substrata, and it was ex- pected that the facultative anaerobic population would increase relative to the aerobic population. However, the data (Figures 8, 9, 10) indicate that there were no significant differences between the numbers of anaerobes and aerobes. Several reasons may account for the low anaerobic bacterial popula- tion. Methodology is the primary rea- son: (1) 2216 Marine Agar is a selective medium, preventing the expression of certain anaerobes; (2) sensitivity of strict anaerobes to 02; and (3) essen- tial vitamins and minerals required by fastidious anerobic bacteria were not provided in the medium. The procedure allowed only the expression of faculta- tive heterotrophic anaerobes. The relative numbers of aerobes and anaerobes in the dredged materials were an order of magnitude lower than the bacterial numbers in estuarine sediments from the North Inlet Estuary, South Car- olina (Stevenson et al. 1972). Grain si-ze has a tremendous influence on bac- terial numbers in sediments and the medium to coarse sands at BSHDS may ac- count for the low population density. YEAST BIOMASS The relative abundance of the yeast populations in the middle tidal zone was also investigated with respect to depth and time (Figure 11). The yeast popula- tion decreased with depth similar to bacterial populations and ATP concentra- tions. The yeast population was approx- imately an order of magnitude lower than the bacteria population. ALGAL POPULATIONS The diversity of the benthic algal community increased between January and September 1976 (Table 2). In January, approximately 7 genera of diatoms were observed whereas by September an addi- tional 10 genera were observed at the BSHDS. The increase in ATP concentra- tions over time in the surface strata may in part be due to the colonization of these diatoms. Blue-green algae were occasionally found but were not domi- nant. Oscillatoria was the primary alga found on the sediment surface. PROTOZOANS AND MEIOFAUNA POPULATIONS Protozoans and meiofauna have been observed in most of the sediment stud- ied. Qualitatively, the fauna were more abundant towards the end of the summer. Garbisch et al. (1975) and Cammen (1976b), working with dredged materials in Chesapeake Bay, reported an invasion of microinvertebrates. Such an invasion may be occurring at BSHDS, but the impact on the microbial flora is unknown. SIMPLE BOX MODEL FOR BSHDS A conceptualized view on the flow of carbon (energy) in the system is shown in Figure 12. Bacteria, yeast, algae, and meiofauna are the major biological components in the het- erotrophic compartment. Most of the heterotrophic energy is obtained via the autotrophs (marsh plants and algae) either as particulate organic carbon or dissolved organic carbon. Tides support some of the energy requirement of the heterotrophs and enhance the overall productivity of the coastal ecosystem with the deposition of detritus. In addition to tidal deposition of detritus, tides seed the habitat with living organisms. In return they enhance the flow of energy through the system. Microbes and macrobes are well known as decomposers and nutrient regenerators in aquatic systems and probably are more important in supplying nutrients to the macrophytes than are rivers and oceanic water of Georgia. Some preliminary stud- ies in Georgia marshes indicate that most of the annual Spartina production 45 30 25 20 15 10- 5- - 0-2cm _ S parting alterniflora • — Aerobes O— - Anaerobes "•©■ o> 0) * >* ^_ o ■o w — » .2 J° "C "7 a> o o ° oo i. in O 30- 10 -12 c 25 20 15 10 5 JAN FEB MAR APR MAY JUNE JULY AUG SEPT Figure 9. Bacterial biomass (CFU) in Spartina patens plots in the middle tidal zone. See Figure 8 for details. 47 No Plants • ——Aerobes O— — Anoerobes o> 30 a> $ 25 >< o ■o 20 k_ i a> u a 15 o o GO Z5 Ll. 10 O 5 ID O 5-7 cm 30 - 10-1 25 20 15 10 5 t Nik= JAN FEB -=*£~ MAR APR MAY JUNE JULY AUG SEPT Figure 10. Bacterial biomass (CFU) in nonplanied plots in the middle tidal zone. See Figure 8 for details. 48 * u o u in O 105 90 75 . Sportina patens • 0-2 cm O 5-7 A 10-12 60 45 30 15 JAN FEB MAR APR MAY JUNE JULY AUG SEPT Figure 1 1. Yeast biomass (CFU) in Spartina alterniflora, Spartina patens, and nonplanted plots in the middle tidal zone at three depths: •, 0-2 cm; o, 5-7 cm; and A, 10-12 cm. CFU's for each block were pooled and the mean ±SE plotted. 49 Table 2. List of diatoms observed at Buttermilk Sound habitat development site. Genera present Month January3 September Navicula + + Pleurosigma + + Amphi pleura + + Epithemia + + Meloseia + + Fragilaria + + Cyclotella + + Mastogolia - + Nitzchia - + Denticula - + Eunotia - + Frustulia - + Chaetocerous - + Cocconeis - + Amorpha - + Achanthes - + Coscinodiscus - + a + = present; - = absent 50 TIDAL INPUT * SEDIMENTS HETEROTROPHS nutrient regeneration N,P, 81 minerals 4 DETRITOVORES GRAZERS Figure 12. Schematic representation of carbon and nutrient cycling in connection with coastal ecosystem development of dredged materials. 51 is supported by nutrient recycling in the marsh (Haines et al. 1975; Chalmers et al. 1976). Therefore, based on the information available, nutrient regener- ation by microbenthos and macrobenthos and tidal input of particulate organic carbon (detritus) play an essential role in coastal ecosystem development. LITERATURE CITED Bancroft, K., E.A. Paul, and W.J. Wiebe. 1976. The extraction and measure- ment of adenosine triphosphate from marine sediments. Limnol .Oceanogr. 21:473-480. Cammen, L.M. 1976a. Accumulation rate and turnover time of organic carbon in salt marsh sediment. Limnol. Oceanogr. 20:1012-1015. Cammen, L.M. 1976b. Macroinvertebrates colonization of Spartina marshes artifically established on dredged spoil. Estuarine Coastal Mar. Sci. 4:357-372. Chalmers, A.G. , E.B. Haines, and B.F. Shen. 1976. Capacity of a Spartina salt marsh to assimilate nitrogen from secondary treated sewage. Tech. Completion Rep. USDI/OWRT Project A-057-GA, Environ. Resour. Cent., Georgia Inst. Tech., Atlan- ta. Christian, R.R., K. Bancroft, and W.J. Wiebe. 1975. Distribution of microbial adenosine triphosphate in salt marsh sediment of Sapelo Island, Georgia. Soil Sci. 119: 89-97. Garbisch, E. W. , Jr., P. B. Waller, and R. J. McCallum. 1975. Salt marsh establishment and development. Tech. Memo. 52, U.S. Army Corps Engin. Coastal Engin. Res. Cent. , Ft. Belvoir, Virginia. Haines, E. B., A. G. Chalmers, R. B. Hanson, and B. F. Sherr. 1975. pools and fluxes in a salt marsh. In M. L. Nitrogen Georgia Wiley, Vol. 3. Hanson, R. B ed. Estuarine research, and W. J. Wiebe. 1977. Heterotrophic activity associated with particulate size fractions in a Spartina alterniflora salt-marsh estuary, Sapelo Island, Georgia, and the continental shelf Mar. Biol. 42:321-330. 1971. Fundamentals of W. B. Saunders Co., Phila- U.S.A waters. Odum, E. P. ecology. delphia. Stevenson, L. 574 pp. H., C. E. Millwood, and B. H. Hebeler. 1972. Aerobic, hetero- trophic bacterial populations in estuarine water and sediment. Pages 268-285 in R. R. Colwell and R. Y. Morita, eds. Effects of the ocean environment on microbial activi- ties. Univ. Park Press, Baltimore. ACKNOWLEDGEMENTS Photographs of the Buttermilk Sound Habitat Development Site were provided by Dr. R.J. Reimold. 52 DETERIORATION OF MARSH IN SAN FRANCISCO BAY Herbert L. Mason 1190 Sterling Avenue Berkeley, California 93306 I was asked to discuss deteriora- tion of ecosystems. This puzzles me be- cause I have been rather critical of the notion of the ecosystem all my life. System belongs to mathematics and logic, not to biology. You never will find a pure example of the ecosystem because nature is so variable. You will find a pattern around which your data will vary. However, the data is correlated with the system; it is not the system. I have just been dealing with a problem of the deterioration of an eco- system, the delta system of the San Joaquin and Sacramento rivers as they flow into San Francisco Bay and join a group of marshes. I discovered the dom- inant effect of plundering one resource and what happens to it. The primary natural resource in the marsh is its capacity to act as a living filter that maintains the water quality of the sys- tem. There were 777 to 1,036 km2 (300 to 4002 mi ) of delta marshes at the mouths of the San Joaquin and Sacramento Rivers. Someone discovered there was land under those marshes that was worth cultivating, so he drained the area and got it out into the open. The first loss was the natural fil- ter that maintained the water quality of the San Francisco Bay. The second loss was the fisheries of San Francisco Bay. The loss of marshes included the salt marshes of San Francisco Bay, and the total destruction was between 95% and 97% of the marsh area. The area was diked, the remaining water pumped off, and the land left to dry out. So we lost the filter system. I do not know how you could evaluate that in terms of dollars but it was an enormous thing. Now there are no commercial fisheries in San Francisco Bay. This change did not occur instantly; the last fishery to go was a tiny shrimp with a very nice fla- vor. Oyster and shrimp fisheries, crabs, and practically everything else disap- oeared because the impurities that came into San Francisco Bay were no longer going through a natural filter. The next loss was when the marsh lands were exposed to the hot, dry California air: the peat began to shrink and it began to settle because of farm equipment on it and the annual plowing that broke up the soil. Plowing pulver- ized the surface and it began to blow away. A related problem was the tectonic settling of land: the lowering of the entire west coast 10.7 m (35 ft) in 10,000 yr. Land which was at tidal level is now 6.4 m (21 ft) below sea level. So the farmers lost the invest- ment they had put in the land. When the dikes broke, the farmer said, "I can not afford to repair the dike because the land is not worth it." He lost his land and the State lost the land's agricul- tural potential. The total loss involves an enormous amount of money. Thus, man destroyed a whole series of natural resource values that were very important to us and resulted in the deterioration of a gigantic ecosystem which includes human beings. Not only did drainage of the delta marshes affect the San Francisco Bay, but the fisheries along the coast of central California also never recovered from that loss. I suspect that if someone knew all the facts, the losses would be traceable to the decline in quality of water that came into San Francisco Bay as a conse- quence of losing the extensive marsh system. Last week the Bureau of Water Qual- ity control voted to allow the lowering of the quality of water that is permit- ted to enter Susson marsh because there is not enough fresh water to supply the needs of Los Angeles. Therefore, Susson marsh will suffer. Susson marsh is important to the ecosystem because it has about 140 plant species whereas the bay salt marshes have only 9 or 10 spe- cies. No two plants of a given kind have exactly the same range of tolerance for 53 everything in the environment. The range of tolerance for the species is greater than the range of tolerance for any one individual. Man is destroying over one- half of the system by changing Susson to a salt marsh because he is doing away with the enormous diversity in the fil- tering capacity of the system. People did not know what they were doing when they decided to take more freshwater from Susson marsh. Soon it will mainly be a saltwater marsh. It has been said that no culture that is dependent upon irrigation has ever survived. The Inca culture disap- peared. You can still find the aban- doned agricultural terraces. The Inca culture died out as a consequence of salination of the soils. The same thing happened to the cradle of agriculture in the Middle East. The soils became salty when water evaporated and left dissolved salts on the soil surface. The same happened in Greece — irrigated soils be- came too saline to grow crops. The Bureau of Reclamation (BR) has done some brilliant research on this problem and they may have resolved the problem with a system of natural filters that are combined with artificial fil- ters. BR drains the agricultural water through the soil and they claim that picks up most of the pesticides. They say they have never found more than a trace of pesticides after the water goes through the soil. Pipes under the soil pick up the wastewater and it is drained through an anaerobic filter. The process is going to be costly because they need to continually feed the anaerobic filter with a carbon salt source. They are go- ing to have to add dried plant material for the anaerobic organisms to feed on as they take up the salts that they re- quire. BR expects to build a long sys- tem of marshes where they hope to keep this water zigzagging back and forth to get the greatest mileage out of the marsh system and to get rid of enough dissolved solids so that the water can be returned to the bay. But the big problem is eliminating the salination of soils in arid regions. We know actu- ally very little about natural filters. 54 SAND DUNE HABITAT CREATION ON THE PACIFIC COAST Wilbur E. Ternyik Wave Beach Grass Nursery Post Office Box 1190 Florence, Oregon 97439 Initial stabilization of sand dune areas should be done by planting Euro- pean beach grass (Ammophila arenaria). Clean plants by shaking sand and silt from the roots. Remove stalks and trash from the culms. Break off the un- derground stems so that one or two nodes remain. Sort grass culms and tie them into bundles weighing approximately 4.5 kg (10 lb). Cut the tops so that the overall length of the planting stock is about 50 cm (20 inches). Plant in hills with at least three live culms per hill and a spacing be- tween hills of about 46 cm (18 inches). Plant the grass to a depth of 30 cm (12 inches), cover with sand or silt, and compact the soil to exclude air from the roots (nodes). The top of the plant should extend approximately 20 cm (8 inches) above the ground. Do not plant on any area until the moisture is within 8 cm (3 inches) of the ground surface. Do not plant when the temperature ex- ceeds 16° C (61° F) or when freezing conditions prevail. Fertilize plantings with ammonium sulfate commercial fertilizer (Elephant brand or equal) at the rate of 45 kg/ha 40 lb/acre) of available nitrogen. Apply the fertilizer on a calm day and during a season when rain can be expected peri- odically (irrigation may be substituted for rain). The planting stock should be plant- ed within 8 hr after removal from the nursery areas or heeling-in beds. The heeling-in beds should be well-drained damp trenches with the roots (nodes) covered with at least 23 cm (9 inches) of soil. Stock should not be kept in heeling-in beds longer than 2 weeks. Before they are planted at the planting site, the plants must be kept in a cool, shady place or otherwise protected against damage from excessive drying. The planting stock may be handled and transported by any method that does not damage the planting stock or the area to be planted. Continual mainte- nance is required on beachgrass for about the first 2 yr; after that, only periodic maintenance is required. When large blowout or blowover areas develop, the most effective maintenance procedure is to replant with beachgrass and then spread brush on the steep edges. Refer- tilizing all weak areas seems to bring back a sufficient cover, if the plant root systems have not been uncovered. Secondary or permanent stabiliza- tion in uplands or border plantings as- sociated with a deflation plain usually is accomplished by one of two methods. In most areas, the beach grass plantings are 2 yr old, when follow-up plantings of 1-0 Cytisus scoparius (Scotchbroom) and 2-0 Pinus contorta (lodgepole pine) are planted on 2.4-m (7.8-ft) centers. The planting season is normally 15 De- cember to 1 February. Sctochbroom is used as a temporary plant with several benefits. First, growth is more rapid than the pine so it provides wind pro- tection for about 8 yr. Second, Scotch- broom is a legume and provides some ni- trogen. Scotchbroom is also very fire resistant and provides good upland bird cover and feed. Scotchbroom is normally shaded out between the 10th and 12th yr; the result is a dense lodgepole pine forest habitat that includes other woody species which have invaded from nearby plant communi- ties. Be certain to plan for vegetative firebreaks in large plantings of this kind. Failure to plan for firebreaks can result in large losses to permanent cover and creation of very adverse con- ditions for rehabilitation. Two species are most commonly used. The best is Lathyrus japonious seeded in a permanent grass mixture. Seeds are treated with H0SO4 or scarified. Fires with intense heat rarely burn over 4 m (13 ft) into a stand of this plant. The other plant is 55 Scotchbroom; 1-0 nursery-grown plants are planted on 1-m (3-ft) centers in solid bands 15 m (49 ft) wide. Scotch- broom is very expensive due to nursery costs; the seed treatment for nursery plantings includes scarification or hot water treatment. The second method used to stabilize border or upland areas, mainly in the Clatsop Plains project, has been disking of beachgrass, followed by seeding to a permanent grass mixture. A fall plant- ing should be considered because rain is infrequent in spring. The seed mixture for drier upland sites is the following: Lupinus 1 ittoralis Poa macrantha Lathyrus japonicus Festuca rubra 7.8 kg/ha (7 lb/ acre) ; 16.8 kg/ha (15 lb/ acre); 16.8 kg/ha (15 lb/ acre); and 9.0 kg/ha (8 lb/ acre). If the first three species are not available, then an alternative mixture of seed normally that is available on the commercial market is the following: Festuca rubra 9 kg/ha (8 lb/acre); Lol ium multiflorum 5.6 kg/ha (5 lb/ acre) ; Vicia villosa 28 kg/ha (25 lb/ acre) ; and Festuca elatior 11.2 kg/ha (10 lb/ acre). All seedings should receive 16-20 or 12-12-12 fertilizer application at a rate of 336 kg/ha (300 lb/acre). When selecting sites for upland habitat improvement, the land manager should consider the complete habitat for all expected users. A mixture of forest, grasslands, and open sand is most desir- able. The dry upland dune sites lend themselves to multiple use management for wildlife habitat and human recrea- tion. Long-range effects of creating new vegetative habitats should be care- fully analyzed before planting. I do not favor stabilization efforts unless coastal dunes are threatening existing resources, or lack some varied habitats. The deflation plain offers the best opportunity in the Pacific coastal dunes for intensive habitat creation and man- agement. Selected areas, usually formed by prevailing winds scouring areas be- hind foredunes, are excellent. After being scoured by the wind, down to the water table, the seed bed is perfect for machine-drilled seed mixtures. Some areas can be used year after year with some site preparation such as disking and leveling. In the Pacific Flyway we concentrate on a mixture that supplements the dwindling food supply for wildlife. Seeding should occur in late May or early June, the date depending on when the wind scouring reaches the summertime water table. Planting too early results in germination, some growth, and then total failure. In addition, the irregu- lar edge caused by failure results in real problems in following seasons due to uneven terrain. After the judgment had been made to plant, the following mixture is seeded and fertilized. (Forest Service Mixture): Barley 112 kg/ha (100 lb/ acre); Perrenial rye grass 7.8 kg/ha (7 lb/ acre) ; Alta fescus 25 kg/ha (22 lb/ acre) ; Lotus major 4.5 kg/ha (4 lb/ acre); and fertilizer 13-13-13 224 kg/ha (200 lb/ acre). Seed should not be drilled until the water table is at the surface of sand. Apply mixture at approximately 100 kg/ha (90 lb/acre). Areas to be seeded with barley or barley-grass seed mixture should be fertilized with com- mercial fertilizer at the rate of 45 kg of nitrogen, 90 kg of phosphate, and 90 kg of potash per acre (448 kg/ha [400 lb/acre]) of 10-20-20 fertilizer. Fer- tilizer should be applied immediately prior to or concurrent with drilling of seed. Fertilizer may be applied either by hand or mechanically, after planting is completed, during or immediately prior to rain, and only on days when wind velocities are low enough so as not to cause significant drift of the fer- tilizer. Seed should be drilled with either a single- or double-disk grain drill. Barley used in this mixture has several roles. First, it germinates in not more than 2 days. This rapid growth allows it 56 to serve as a "nurse crop," preventing wind erosion to the slower germinating permanent grasses and legumes. We have occasionally produced 100 bushels/ ha; thus, the fall feed for migratory water- fowl is plentiful. All deflation plains are flooded by heavy rainfall in winter. In one 100-ha (247-acre) planted area, we have counted as many as 2,000 geese, hundreds of ducks, and 1,500 swans. This use by waterfowl was in contrast to only occasional overnight rest stops in the same area before planting. One flock of geese, which contained marked identifiable members, remained in the area for 6 weeks in mid- winter. The permanent grasses and leg- umes were grazed especially heavily by the swans and northbound black brant (Branta nigricans) in the spring. How- ever, repeated plantings tend to build up organic material to the point where disking becomes increasingly difficult. Seeding only barley would lessen this problem. The legume, Lotus carniculatus, can survive several months underwater without adverse effect. This plant is heavily grazed by blacktail deer (Odo- coileus hemionus). Areas bordering the deflation plain may have to be stabilized to avoid dam- age to seeded areas by blown sand. Planting of American beachgrass (Ammo- ph ila arenaria) and woody species will afford protection and provide excellent nesting areas with dense protective cover. In the Oregon dunes, we also an- nually release ring-necked pheasants (Phasianus colchicus). However, the ever-increasing vegetation makes hunting difficult. The transplanting of beaver (Castor canadensis) also increased water tables throughout much of the deflation plains. Be cautious, however, because vegetative plantings may result in total natural revegetation of the entire de- flation plain. Even though a planting makes excellent habitat.it also cuts off the ocean supply of sand. Our plantings have been cooperative efforts between the Oregon Fish and Wildlife Commission and Federal landowners (U.S. Forest Ser- vice or BLM). In my 34 yr of experience, no other areas produced results as quickly. The Oregon Coastal Conservation and Develop- ment Commission in our Coastal Zone Management program requests clear iden- tification of all potential deflation plains sites and encourages their pre- servation. With the ever-increasing en- croachment of man's activities on exist- ing coastal habitats, these areas should be preserved whenever practical. 57 DUNE COMMUNITY CREATION ALONG THE ATLANTIC COAST Ernest D. Seneca Departments of Botany and Soil Science North Carolina State University Raleigh, North Carolina 27650 The information that I report is the result of research conducted along the Atlantic Coast by Dr. W. W. Woodhouse, Jr., Dr. S. W. Broome, and me. Suggested references include Woodhouse (1978) and Woodhouse et al. (1968, 1976). We have received support from the Coastal Engineering Research Center, U.S. Army Corps of Engineers; the University of North Carolina Sea Grant Program; and the North Carolina Coastal Research Program. I am going to describe the function of sand dunes along the Atlantic Coast; how to build and stabilize them, what is good and bad about them, some applica- tions, and some of the knowledge that we have accumulated during the past 15 yr of research. Coastal dunes are natural features of most sandy shorelines, especially in temperate regions. They result largely from sand being trapped by vegetation. Onshore winds move sand onto the beach. Along the North Carolina coast, north- east winds are primarily responsible for moving this sand from deposits above the high tide line, on a berm, onto the dunes. Almost any obstruction in the path of blowing sand will cause it to settle out, accumulate, and build a dune. Perennial grasses are especially efficient at facilitating this task. The native dune community along the Atlantic Coast is dominated by perennial grasses. Northward of Virginia, American beachgrass (Ammophila brevil igulata) is dominant; from North Carolina southward to Florida and along the Gulf coast to Texas, sea oats (Uniola paniculata) dom- inates. Because of their dominance and their superior sand-trapping capacity, perennial grasses are used to initiate dune development. Although these perennial grasses reproduce both sexually and asexually (vegetatively) , vegetative reproduction by extensive rhizome systems is most important in stabilizing the sand and building a dune. The principal grasses used in dune creation along the Atlantic Coast are American beachgrass, sea oats, and bitter panicum (Panicum amarum). New shoots and roots arise intermittently along the rhizomes of these grasses. In the case of American beachgrass, rhizome growth can enable a dune to migrate to- ward the sand supply at a rate of about 1.4 m (4.4 ft)/yr. Coastal dunes are flexible bar- riers. They are part of the nearshore dynamic zone that changes with the wave climate both seasonally and in response to sporadic storm activity. Dunes serve as sand reservoirs to nourish the beach during storm attack. A portion of the dunes may be eroded, the material car- ried out in the surf zone and deposited on offshore bars, and then returned at some later time. As much as 3 m (10 ft) of sand at the base of the dune may be taken out during a severe storm. A sig- nificant portion (over half) of this sand may return within the next two or three tidal cycles; in time most of it may return. Unfortunately, man does not often appreciate the fact that foredunes are a part of this dynamic zone, which is continually undergoing change. Further, sea level is rising; it may be only 2 to 3 mm (0.08 to 0.12 inch) a year, but coastal lands are being claimed by the sea and the forces of erosion. Coastal dunes are not effective barriers against this type of situation. Nature is taking what it needs to establish new beach and shore- line profiles. There is little that man can do without tremendous expenditures to change this trend. Coastal dunes can be built in many ways and the method used may influence the vegetation that exists on them. Substrate moisture conditions in dunes are related to the texture of the sand which in turn may be a result of the 58 method used to construct the dune. Dunes can be built mechanically with a bull- dozer, hydraul ically with a pipeline dredge, with sand fences, or by a combi- nation of methods. First, consider push- ing up sand with bulldozers. This is actually dike-building and is at best a temporary means of halting the ocean's advance. It is usually resorted to only in emergency situations. During the Ash Wednesday storm of 1962 along the North Carolina coast, personnel of the Cape Hatteras National Seashore worked all night with a bulldozer to keep a barrier dune intact and prevent overwash from flooding a developed area. Another option is to use a pipeline dredge to pump sand from a barrow area (e.g., sand spit or lagoon) onto the beach and build a new berrr. and dune system hydraul ically. Placement of sand onto the beach in this manner is called beach nourishment. In 1965, the U.S. Army Corps of Engineers nourished Wrightsville Beach, North Carolina, at a cost of about $468,750/km ($750,C00/mi) of beach. This procedure has been repeated since 1965 at a cost of $1,250,000 to $l,875,000/km ($2 to 3 million/mi) of beach. This process may have to be repeated again and again. The economics of the situation in this case might dictate or indicate that beach nourishment, time and again, is the answer in this relatively heavily devel- oped area. A part of the specifications followed by the Corps in a nourishment project is that the upper portion of the nourished area be planted and stabi- lized. Under favorable conditions this will result in dune formation. In some situations a dune can be built with sand fence (snow fence) or with sand fence and vegetation together. Under certain conditions, it is possible to plant grass and, as the grass grows, it accumulates sand, and a dune forms. With this technique, the dune is being stabilized as it is being built. Whether the dune is pushed up me- chanically, pumped up hydraul ically, or formed by fences or grasses, the sand must be stablized to be a protective de- vice. You can accumulate all the sand you want, but sand can be moved by the prevailing winds unless it is stabi- lized. In underdeveloped areas along some coastlines, it is feasible to build a dune just by planting dune grasses. When you consider something like beach nourishment, you are dealing with mil- lions of dollars. A dune can be built in a few years after planting with Amer- ican beachgrass for about $6,250/km ($lC,000/mi). Coastal dunes are abused by man, his animals, and his machines. Grazing has been a major problem in the past; traffic, both foot and vehicles, is a major problem now. Almost any dune system along the Atlantic coast or Gulf of Mexico at one time or another has undergone grazing pressure by various domestic animals, including sheep, cattle, horses, pigs, and goats. These animals had a tremendous impact and in many cases completely denuded the coastal dunes. Some present-day ecologists say dune systems are in a dynamic equilibri- um even though man has interfered with these systems for several hundred years. Presently, the problem is not grazing but man's impact with foot and vehicular traffic. Dune vegetation is very suscep- tible to damage by traffic. Land manag- ers should control access to beach areas by directing it along wooden, elevated walkways. One of the very desirable features of dune grasses is their capac- ity to reestablish following storm ac- tivity. Traffic interferes with this capability of the vegetation. There is no way that plants can reproduce well in areas used heavily by vehicles. Dune buggies may have their place, but it is not on a frontal dune system along the Atlantic coast. Get them further inland, possibly on certain live dunes. The absence of dunes along most of the Atlantic coastline is usually due to a lack of sand or sufficient winds to move the sand onto the vegetation, or due to man's interference through his activities, or his animals' activities. Dunes are natural features. They will develop if there are vegetation and a sand supply. Placement of vegetation about 100 m (330 ft) from the high tide line will result in dune formation pro- vided there is an adequate sand supply. Dunes are fragile structures re- quiring protection and stabilization; vegetation is usually the only practical 59 solution. What particular features must coastal plants possess to stabilize dunes? They must have physiological and morphological features that enable them to live in the relatively severe habitat at the land-sea interface. What have we accomplished along the North Carolina coast in the last 15 yr in terms of stabilizing the unstabilized dune areas and in building dunes in some areas where we thought they should be placed? American beachgrass occurs nat- urally around the Great Lakes and along the Atlantic coast from Nova Scotia to northern North Carolina. It is the prin- cipal grass used to build and stabilize dunes along the Atlantic coast, includ- ing areas southward of its natural dis- tribution. Why? Because it is relative- ly easy to propagate in the nursery, is relatively easy to handle and prepare for transplanting, grows rapidly after planting, has a relatively long growing season compared to other grasses, and is a very efficient sand-trapper and dune builder. Nursery-grown strains of Amer- ican beachgrass have been field-tested for superior vigor under localized con- ditions in both New Jersey and North Carolina. Selections have been made based on these tests and locally adapted varieties are now available through com- mercial growers. What about fertilization response? Dune grasses respond favorably to fer- tilization. The primary response is to nitrogen with a minor response to phos- phorus and little or no response to po- tassium. A 30-10-0 fertilizer is recom- mended, applied at the rate of about 23 kg/ha (50 lb/acre). Do not apply more than this amount of nitrogen at a time. Any amount in excess of this will, in all probability, be leached from the soil. Granulated fertilizers are readi- ly available and easy to apply with a cyclone seeder. Do not put the fertiliz- er on when you plant. Wait until the root systems develop; then apply it on several occasions so that your total may be 68 kg (150 lb) the first growing sea- son. If planting takes place in February or March, apply 23 kg (50 lb) of nitro- gen in late Kay, the same amount in July, and again in August or September. With these split applications, plants are able to make maximum use of the fer- tilizer materials. If you have a large area of dune system to fertilize, a helicopter can be used. Pelletized fer- tilizer can be very evenly distributed by helicopter. After the pellets absorb water, they adhere to the sand. American beachgrass should not be used alone in dune plantings along the south Atlantic coast. It is less drought tolerant and less tolerant of high tem- peratures than either sea oats or bitter panicum. Further, it is susceptible to a scale insect (Eriococcus carol inae) and also a fungal pathogen (Marasmius). The fungus, which causes Marasmius blight of American beachgrass, is not known to occur north of North Carolina. Any planting of American beachgrass made south of about Oregon Inlet, North Carolina, will be invaded by sea oats in time, provided that there is a seed supply of sea oats nearby. Usually, in 8 to 10 yr after a dune is planted to pure American beachgrass, the beachgrass is replaced by other species, primarily sea oats. Still we use American beach- grass to initiate dunes and provide the initial cover. Why? Because beachgrass establishes quicker and traps sand at a faster rate than any of the other plants available. Our major emphasis at present is to determine the best adapted strains of native plants and to determine the best mixture of these plants to use for sta- bilization. We have experienced almost complete failure with saltmarsh cord- grass (Spartina patens) except in a few places. It is found on dunes, but does not do well when planted alone. In mixed plantings with sea oats, and sometimes with bitter panicum, it does very well. Some of you may wonder why we do not experiment with some other types of plants besides grasses. We are looking at some other species, such as seashore elder (Iva imbricata), a succulent- leaved semi-woody plant of the aster family. We are studying its physiology, germination capability, and response to transplanting. In places, seashore elder dominates the dune community, but we do not think that it is a particu- larly good stabilizer and recommend its use only in mixed species plantings. Results of mixed species plant- ings have led us to realize their advantages over conventional monocul- tures. A mixed species experimental 60 planting on Ocracoke Island, North Caro- lina, included 50% American beachgrass and 50% sea oats. After 10 yr sea oats still dominate much of the zone where the sand is no longer active or accumu- lating. In the active sand zone where it is accumulating on the ocean side of the dune, American beachgrass dominates. This is a characteristic response of American beachgrass; it does best where fresh sand is accumulating and it will grow toward the sand supply on the beach (berm) at a rate of up to 3 m (10 ft) per year. The rhizome network of Ameri- can beachgrass has much greater poten- tial for spread than does that of sea oats. Even though American beachgrass has some problems (e.g., disease, insect pests) along our coastline, it also has some definite advantages. In mixed spe- cies plantings, beachgrass acts as a nurse crop, builds the dune, and has the capacity to alter the dune's configura- tion by growing toward the sand supply. Eventually beachgrass will surrender dominance to other plants which results in a natural vegetative composition which is what we wanted in the first place. In many cases in the past, man- initiated dunes have been placed too close to the ocean. Sandy shorelines advance and retreat; initial placement of a dune planting must allow for this movement. Because the overall trend along much of the Atlantic coast is that of a receding shoreline, dunes should be built at least 100 m (33 ft) from the high tide line. In another mixed-species experiment near Drum Inlet, North Carolina, we put in a 0.6-m (2-ft) sand fence to accumu- late a small ridge of sand prior to planting. We did this to gain a little elevation on a very exposed beach. The planting included sections of American beachgrass, sea oats, and bitter pani- cum, alone and in combination. By the third growing season, the American beachgrass section had accumulated more sand and moved further toward the ocean than either the bitter panicum or the sea oat sections. A section of the bit- ter panicum and sea oats together did almost as well as the section of Ameri- can beachgrass alone; however, the mix- ture did not migrate as far toward the ocean. The mixture of American beach- grass and bitter panicum was no more effective than that of American beach- grass alone. American beachgrass is still superior to anything else that we have tried. When we planted a three-way mixture (American beachgrass, sea oats, and bitter panicum), a dune was created that was a little steeper on both the front and back slopes than dunes created by American beachgrass alone. For all practical purposes, however, sand accum- ulation was the same. Experiments indicate that it is best to use mixtures of grasses to stabilize and build dunes along our coastline, even though Ameri- can beachgrass alone might accumulate sand at a faster rate. The mixture is best because American beachgrass is subject to disease and insect problems which become evident the second growing season following planting. Coastal foredunes are the first line of defense. They are dominated primarily by perennial grasses with a scattering of other plants. Woody plants do not appear to be the answer to problems involved with dune building and dune stabilization with a situation of rising sea level and a retreating shore- line. Shrubs grow on the back side of the foredune and in other protected areas. They cannot survive on the top and ocean slope of the foredune because they cannot withstand the high concen- trations of wind-borne salt spray. Be- hind the foredunes there may be inner dune areas, swales, or sand flats, where grasses and other herbaceous vegetation still dominate, but where shrubs become more prominent. Still further inland, a zone of woody vegetation develops. This woody vegetation may be a low-growing maritime shrub thicket or it may be a maritime forest. It is composed of wax myrtle (Kyrica cerifera), yaupon (Ilex vomitoria), red cedar (Juniperus virgin- iana), five oak (Quercus virginiana), and laurel oak (Quercus lauri folia) to- gether with greenbriar (Smil"ax spp.), wild grapes (Vitis spp.) and poison ivy (Rhus radicansj! Where you find trees or shrubs next to the ocean, it is prob- able that the ocean has cut to them, not that the trees and shrubs have grown toward the ocean. In summary, coastal foredunes are 61 dynamic natural features along our coastline which are usually dominated by perennial grasses. They are fragile structures which may be damaged or destroyed by man's activities, as well as by natural forces. They afford pro- tection and are important in preserving the coastal fringe, but be considered permanent provide lasting protec- structures such as roads They require protection the integrity of they should not structures which tion for man's and buildings. and appreciation of their role in coastal systems. LITERATURE CITED functional Woodhouse, W. W. Jr. 1978. Dune building and stabilization with vegetation. U.S. Army Corps of Engin., Coastal Engineering Re- search Center, Ft. Bel voir, Vir- ginia. Spec. Rep. 3. 112 pp. Woodhouse, W. W. , Jr., E. D. Seneca, and S. W. Broome. 1976. Ten years of development of man-initiated coast- al barrier dunes in North Carolina. North Carolina State Univ. at Ra- leigh. Agric. Exp. Stn. Bull. 453. 53 pp. Woodhouse, W. W. , Jr., E. D. Seneca, and A. W. Cooper. 1968. Use of sea oats for dune stabilization in the southeast. Shore and Beach 36(2): 15-21. 62 MANGROVE SWAMP CREATION Howard J. Teas Department of Biology University of Miami Coral Gables, Florida 33124 INTRODUCTION Mangroves are trees and shrubs that grow at the edge of warm seas of the world. They dominate 75% of the shore- line between 25° North and 25° South latitude (McGill 1959). Mangroves reach their maximum development and diversity in Southeast Asia (Macnae 1968) where Chapman (1970) listed 44 species and 14 genera. By contrast, Chapman tabulated only eight species and four genera in the Western Hemisphere. The Florida species are the red (Rhizophora mangle), black (Avicennia germinans), and white (Laguncularia racemosaT mangroves (Figures 1 through 3j! All three species occur in the southern part of Florida. White man- grove is the most cold-sensitive of the three species, red mangrove is interme- diate, and black mangrove (which grows from just south of Jacksonville on the east coast, around the peninsula of Florida, and westward along most of the U.S. Gulf coast to Mexico) is the most cold-resistant. Red mangrove fruits germinate on the parent tree to form pencil -shaped propagules (unrooted seedlings). Black and white mangroves form fruits which, like red mangrove propagules, drop from the tree when they are mature. A mangrove swamp is a complex eco- system. Although the species of plants are relatively few, the animals are num- erous and diverse (Macnae 1968). The goal of a mangrove planting or replant- ing program should be the development of a functional, diverse ecosystem. In this report I will cover factors that are known to be involved in man- grove establishment, review mangrove planting experiments, and evaluate the state of the art of mangrove swamp crea- tion. ECOLOGICAL FACTORS IN MANGROVE ESTABLISHMENT LIGHT Mangroves require open sunlight for optimal growth. The light intensity at ground level under a full canopy of man- grove forest may be only 5% to 10% of the open sun values. Mangrove seedlings ordinarily require more light than this to grow and become trees. Seedlings that fall to the ground under parent trees or are carried by the tides to areas of heavy canopy shade may begin development, but most die. An interest- ing feature of the growth-limiting effects of low light levels can be seen in the portion of a mangrove forest where the canopy has been removed by a lightning strike (Teas 1974). Dense growth of seedlings is found in such lighted openings; however, in nearby shaded areas the low light level sup- pression of seedlings continues (Figure 4). TIDAL DEPTH AND FLUSHING Another factor in mangrove estab- lishment is tidal depth. Many red man- grove seedlings become planted and begin to grow along the shore of Biscayne Bay below mean sea level and even below mean low tide (Figure 5). However, aerial photographs over a decade showed that none of the seedlings at the site shown in Figure 5 developed' into trees at substrate elevations lower than -9 cm (-0.34 ft) below mean sea level (Teas 1976). Roots of mature red mangroves often extend 30 cm (12 inches) or more below mean low tide in channels between mangrove islands in south Florida. The difference may be that the roots of the mature trees have well -developed aeren- chyma (air conducting) tissues, whereas 63 Figure 1. Red mangrove, showing prop roots. 64 Figure 2. Black mangrove, showing pneumatophores, the characteristic slender vertical aerial roots. 65 Figure 3. White mangrove on dry (filled) land. 66 Figure 4. Growth of mangroves under canopy opening caused by a lightning strike. 67 Figure 5. Biscayne Bay shore at a low tide, showing red mangrove seedlings in foreground at substrate elevations too low for trees to become established. 63 the nonspecial ized roots of young seed- lings probably suffer from anaerobiosis. The failure of young seedlings to de- velop in deep water is probably the rea- son why moderately shallow bays do not become overgrown by red mangroves. Large areas of mangroves have been killed in the past by reducing or block- ing tidal flow to mangroves with highway construction and diking. Indeed, the limitation of tidal circulation by dik- ing, usually combined with pumping water to maintain continuously high water lev- el, has been a standard means by which mangroves were killed prior to filling the land for real estate development. An area in Dade County that was temporily cut off from tidal flow was studied by Teas et al. (1976). Mangroves occa- sionally adapt to reduced tidal flow; however, live mangrove forests are rarely found where completely excluded from tidal flushing. Stoddart et al. (1973) reported one such situation on the is- land of Barbuda in the Lesser Antilles. Mangrove species differ in their response to altered tidal flushing pat- terns. Both black and white mangroves in Florida are typically more resistant to the effects of diking and floodino than are red mangroves. Noakes (1955) reported that in the Malayan mangrove forests channelization, which increases tidal flushing, favors the development of Rhizophora (the genus of Florida man- grovej over several other genera. Evi- dence from occasional survivors among diked Florida mangroves suggests that decreasing tidal flushing of a mixed stand would favor black and white man- groves over the reds, and conversely, that increasing tidal flushing should favor red mangroves over blacks and whites (Teas et al . 1976). SALINITY Salinity is a factor in mangrove growth. No mangroves are considered to be obligate halophytes, that is, to re- quire salt, although they may be facul- tative halophytes, that is, tolerate salt and even grow better with some salt than without salt (Waisel 1972). It has been noted repeatedly in the literature that mangroves grow larger in the zone of lower, fluctuating salini- ties some distance into an estuary from the shore than they do in saline waters near the shore (e.g., Davis 1940). Giant red mangrove trees on Molokai, Hawaii, are not found at the shore, but rather in the brackish zone some distance from the sea (Teas et al . 1975). It has been suggested that the lesser growth of man- groves in the more saline waters may be a metabolic "price" paid for salt toler- ance (Carter et al. 1973; Teas 1974). Mangroves may grow fairly well in freshwater. In 1933, Davis carried red mangrove propagules to the National Bo- tanic Garden in Washington, D.C., where they were grown in greenhouses and reached a height of more than 3 m (10 ft) (Figure 6). I was assured by a long-time employee of the Garden that these mangroves had always been watered with tapwater. There are records of man- groves having been grown in freshwater for a century at Hamburg, Germany (Ding Hou 1958). Mature mangroves of several species can be seen growing in fresh- water several hundred meters above sea level in the Botanical Garden at Bogor, Indonesia (H.J. Teas, unpublished). Ac- cording to Ding Hou, mangroves at Bogor have grown and reproduced in freshwater for more than a century. Thus, mangroves tolerate, but do not require saltwater. This tolerance of saltwater is probably very important to mangroves because it reduces competi- tion from nonsaline tolerant species (Teas 1977). As noted earlier, mangroves do not prosper at low light levels. .Man- groves are slow growing compared to many nonsaline tolerant herbaceous and woody plants that would overshadow and out- compete them if saline soils did not provide the mangroves a competitive advantage. WAVE AND CURRENT ACTION Another factor in mangrove estab- lishment and survival is shoreline ener- gy from natural waves, currents, and boat wakes. Wave action can wash out well-established mangroves. Figure 7 shows a site along the Intracoastal Waterway in Broward County, south of Fort Lauderdale, Florida, where man- groves (and other species)are toppling into the water because of erosion caused by boat wakes. A rock breakwater or barrier of floating tires, of the type 69 Figure 6. Red mangroves growing in fresh water at National Botanic Garden, Washington, D.C. Photo by Dr. P. Schroeder, 1 974. 70 Figure 7. Red mangroves subjected to boat wake erosion, Broward County, Florida. 71 reported by Dr. Seneca in these proceed- ings, might protect such a shoreline. Figure 8 shows red mangroves near the Card Sound Bridge in Florida being subjected to wave erosion. No new seed- lings were becoming established in this area. ROOT MAT AND SOIL HOLDING The relatively greater resistance to wave erosion of the root systems of the black and white mangroves in compar- ison with red mangroves is an important factor in shoreline stabilization and mangrove swamp creation. The root system of red mangroves (Figure 9) does not form nearly as dense a mat as do roots of white or black mangroves. Figure 10 shows the storm-washed (probably hurri- cane) roots of a white mangrove. Black mangroves have a dense root mat similar to the whites. Black and white mangroves are found in areas of higher wave energy than red mangroves, especially on rocky shores. Figure 11 shows black and white man- groves, but no red, that have success- fully colonized an exposed soil bank along south Biscayne Bay, Florida. Also, black or white mangroves are probably better than reds for planting on rocky sites. If rapid shoreline stabilization is desired for protection against erosion, black or white mangroves may be more suitable than reds. Lewis and Dunstan (1975) have suggested that rapid soil stabilization might be achieved by planting Spartina alterniflora, and then planting mangroves in the Spartina. Mangroves appear to compete successfully in such a situation. Rapid shoreline stabilization can be achieved by plant- ing mangroves at greater density, then allowing natural thinning to occur, or thinning artificially, as suggested by Pulver (1975). FLOTSAM AND JETSAM Another enemy of mangrove seedling establishment is floating trash (flot- sam) that can cover, break off, or up- root seedlings. Even mats of the float- ing seagrass or algae can sometimes up- root an unprotected mangrove planting. It may be possible in some cases to con- struct small breakwaters to divert the floating trash from a planting site. SUBSTRATE AND MINERAL NUTRIENTS In a mangrove swamp, which is a "climax" or "subclimax" forest, there is probably a tight coupling of mineral nu- trients. The mineral elements from man- grove leaves, wood bark, and other de- bris that reach the forest floor are efficiently recycled by the trees. Atmospheric nitrogen is fixed by microorganisms in the mangrove soils (Kimball and Teas 1975). The amount of fixation found, on the order of 5.6 to 16.8 kg/ha (5-15 lb/acres) per year, is not spectacular by comparison with an equal area in a field of soybeans. An unknown factor in mangrove swamp nitro- gen utilization is whether or not deni- trification (nitrogen loss) occurs in mangrove soils. As noted by Pomeroy ("Nutrient Cycling in Coastal Ecosys- tems" in this volume) rates of nitrogen loss can offset nitrogen fixation in some soils. In a mangrove forest, some of the mineral nutrients in leaves, fruits and propagules, wood and other debris are lost from the system when carried out with the tide. Along many mangrove shores, mineral nutrients are gained when seagrass, algae, and other plant materials are washed into the forest, decay, and release mineral nutrients. Some soils, such as broken coral and nutrient-deficient leached soils, provide poor substrates for mangrove de- velopment (Macnae 1968). There is some evidence that south Florida marl soils, with their high pH and deficiencies of certain mineral elements, may be a poor soil for mangroves (Teas 1*974 ) . SPHAEROMA ROOT PARASITE The isopod parasite Sphaeroma tere- brans, a pill bug-sized root borer, is a serious problem for red mangroves in some areas (Rehm and Humm 1973). Sphae- roma is also known to attack black and white mangroves (Rehm 1976). In an area of heavy Sphaeroma infestation, para- sites were found even in the timbers of wooden derelict boats (H. J. Teas, 72 Figure 8. Red mangroves in high wave energy area, near Card Sound Bridge in south Florida. 73 Figure 9. Roots of a red mangrove. Photo by Dr. T. Lodge. 74 Figure 10. Roots of a storm-eroded white mangrove in Florida Bay. 75 ^t«i^ ^^*» x^ - #- ■•# ^ * « J" "• > 4J -- . 9k 4» „-*>■ - * -*s "# S-ijf&l *' ? •» jr JS^Hfe* •*' •B .«**> Figure 11. Black and white mangroves established on a rocky shore on Biscay ne Bay. 76 unpublished). The parasite bores into roots and stems of mangroves, weakening them so that they may break off or fall over from the stress of boat wakes or wind. Figure 12 shows a young black man- grove seedling at Port Charlotte, Flor- ida, that has been attacked by Sphae- roma, and Figure 13 shows Sphaeroma- damaged mature red mangroves, 9 to 10m (30 to 33 ft) tall, that are falling into the water along the Intracoastal Waterway in the northern part of Bis- cayne Bay, probably from a combination of boat wakes and Sphaeroma damage (Teas et al. 1976). Hannan (1975) reported that all his plantings of red mangroves located 10 cm (4 inches) too low in the tidal zone at an Indian River site were killed by Sphaeroma, but that trees planted above this level were not at- tacked. DISEASES Olexa and Freeman (1975) reported three fungus diseases of mangroves in Florida. Two of them were pathogenic on black mangroves and one on red man- groves. The latter was identified as Cylindrocarpon didymum and is thought to cause the prominent galls found on red mangroves in south Florida (Figure 14). These authors suggest that the red man- grove disease may cause mortality and that the prevalence of the disease may indicate that the affected mangroves are stressed. The red mangrove gall disease does not often affect young seedlings and has not appeared in our experimental plantings. The two diseases of black mangroves were not reported as wide- spread. It is uncertain at present whether these or other diseases are likely to be a problem in mangrove planting. PUBLIC ACCESS At some experimental sites accessi- ble to the public, there has been damage to planted mangroves (Teas et al. 1975). The technique of providing a sign on the site that explains the purpose of the experiment might reduce such losses. Reimold, at this conference, demonstrat- ed such a sign that was apparently suc- cessful at a Spartina planting site. REVIEW OF MANGROVE PLANTING OLDER LITERATURE Mangroves have been planted for many years. They were planted in Sri Lanka (Ceylon) to induce silt deposition and in Java to stabilize the banks of fish ponds and canals (Macnae 1968). Mangroves were introduced into Ha- waii in 1905 on the island of Molokai to check soil erosion (MacCaughey 1917). Recently, this author (Teas et al . 1975) checked several of the Hawaiian Islands for mangroves and found a well-developed forest of Rhizophora on the southwest coast of Molokai and smaller stands on several other islands. Some of the Rhizophora trees on Molokai were greater than 0.3 m (1 ft) in diameter and esti- mated to be more than 21 m (70 ft) tall. Red mangroves were planted in Flor- ida before 1917 among ballast stones of the Florida Overseas Railway as a pro- tection against storm erosion (Bowman 1917). Davis (1940) reported having planted 4,100 red mangrove propagules at Long Key in the Dry Tortugas Islands. One year later approximately 80% sur- vived, but 32 yr later all had died and/or been washed away by storms (Teas 1977). FLORIDA PLANTINGS SINCE 1970 Savage (1972) reported on plantings of red mangrove seedlings in a variety of situations in the Tampa-St. Petersburg area. He had a low survival rate in most cases. Teas et al. (1975) planted young red mangrove seedlings on the east coast of Florida along waterways leading into the North Fork "of the St. Lucie River. At the Coral Reef Waterway site, which is subjected to waves from boat traffic, there were no survivors after 7 mo from 178 seedlings planted. A low energy site, Canal B-19, had good survival, and a dense growth of mangroves was estab- lished within 5 yr. Figure 15 shows a part of this planting at 4 yr. At the Elkcam Waterway, a moderate energy site, seedlings were planted through a jute mesh mat (Figure 16). The majority of the seedlings were lost or broken, and survival was low after 3 yr. However, at the Elkcam Waterway site, plants on 77 Figure 12. Black mangrove seedling attacked by Sphaeroma at Port Charlotte, Florida. The holes in the stem were caused by Sphaeroma which were still living in the stem. 73 _ Figure 13. Large red (and a few white) mangroves falling over from boat wakes in heavy Sphaeroma damage area, Intracoastal Waterway, Dade County, Florida. 79 Figure 14. Gall on trunk of red mangrove. 80 Vx' ;C / / f / \v%- « Ml » Figure 15. Red mangroves planted at low energy site (Canal B-19) at age of 4 yr. 81 Figure 16. Red mangrove seedlings planted in jute mesh at Elkcam Waterway, St. Lucie County, Florida. 32 the side of the Waterway away from fre- quent human access fared better than those near more frequented areas. Some of the losses at more urbanized sites resulted from seedlings being trampled by fishermen, knocked over by small boats, and in some cases apparently pulled up. Teas et al. (1975) reported on a low energy mangrove planting site on the west coast of Florida at Grassy Point in the Port Charlotte area. At this loca- tion, approximately 60,000 red mangrove propagules were planted in 1974. A por- tion of this experiment is shown in Fig- ure 17. An estimated 85% to 90% survived for 1 yr; however, checks at 2.5 yr (Teas and Jurgens, unpublished) showed that many of the seedlings planted low in the tidal range were being lost be- cause of Sphaeroma damage. Red, black, and white mangroves were transplanted to a high energy site in Biscayne Bay, on the north side of the Julia Tuttle Causeway, and after 10 mo only 7 of the original 320 plants survived; after 24 mo, none was alive. Forty-seven small red, black, and white mangrove trees were transplanted from nature into a freshwater pool at the University of Miami campus (Figure 18), and 47% were surviving after 2 yr (Teas 1977). Most of the fosses were in the first few weeks. At a low energy canal side site near Miami, 88 pot-grown red, black, and white mangroves up to 3.6 m (12 ft) tall were planted. The survival rate after 6 mo was 100% (Teas 1977). Kinch (1975) summarized several years of experiments on mangrove trans- planting to a spoil island in Roberts Bay at Marco, Florida (Figure 19). After 3 yr, only 15.7% of the plants survived. This low survival rate may have been caused at least partly by subsidence of the soft fill used in forming the is- land. Hannan (1975) transplanted 4-yr or older red mangroves in the Jensen Beach area on the east coast of Florida. He obtained good survival, i.e., 85% to 100% at 13 mo, of root-balled plants transplanted at or above the mid-tide range. Teas (1977) used a tree crane to transplant 14 black and white mangroves up to 6m (20 ft) tall (Fioure 20) that had been root-pruned several months earlier and top-pruned at the time of transplanting. After 6 mo none sur- vived. The losses probably resulted from improper handling in transplanting, since root-pruning and top-pruning alone do not kill trees of this size. THE MANGROVE SWAMP ECOSYSTEM Mangroves, growing where tempera- ture, water, salinity regime, substrate, mineral nutrient supply, and other fac- tors are fairly optimal, form well- developed forests that are botanical ly complex. As Macnae (1968) has detailed for Indo-Pacific mangrove forests, many animal species are found living in or dependent on the mangroves. The diver- sity of mangroves inhabitants in the Caribbean is indicated, for example, by lists of animals found in mangroves of Puerto Rico (Cerame-Vivas 1974), Trini- dad (Bacon 1970), and south Florida (Tabb et al. 1962; Odum and Heald 1972; Carter et al. 1973). Birds, fish, in- vertebrates, and mammals inhabiting man- groves in south Florida were listed by Simberloff and Wilson (1969), Breitwisch (1976), de Sylva (1976), Odell (1976), Owre (1976), and Voss (1976). Mangrove detritus-food web relationships have been described by several writers (Macnae 1968; Odum and Heald 1972). Odum and de la Cruz (1967) reported on the role of Spartina detritus in a Georgia salt marsh estuarine ecosystem. There appear to be special problems associated with the establishment of mangroves in unvegetated shoreline areas or in former mangrove areas that have become dominated by other plants. For example, Macnae (1968) points out that clear-cut mangrove forests along the Gulf of Thailand near Bangkok did not revegetate with mangroves. Also, the herbicide-killed mangrove forests on the Saigon River delta were very slow to be- come revegetated long after significant concentrations of herbicide had disap- peared from the soil (Lang 1974) (Figure 21). In Vietnam, erosion of the exposed soil and loss of mineral elements may have been involved (Lang 1974). Areas near Flamingo in Everglades National Park, where the mangroves were killed by a hurricane in 1965, became vegetated 83 I I Figure 17. Hand-planted red mangroves at Grassy Point, age 1 yr. 34 Figure 18. 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This method may be usable in Puget Sound, because the sand fraction of the sediments in the eel grass is fairly heavy, and even with a current of 2 or 3 knots, such as flows over that garden, the sediment remains intact. Sediments of eel grass meadows further south at San Diego may have a larger silt content, and the method probably could not be used there. Zostera seems to be moderately tolerant, and both anchoring and nonanchoring devices can be used for planting. If the silts are too fine, anchoring devices can be used for establishment. In Puget Sound where the sediments are heavy, I can merely cover over the plants, have them establish and fill up a plot very quickly. Where the silts are fine in eel grass meadows, anchoring methods should be used. There is some indication from these experiments and others done in 1970 in another part of Puget Sound, that transplantation done in spring (March through May) gives the best chance of successful establishment. In Izembek Lagoon, Alaska, I have in- stalled a number of eelgrass plots using nails and rods as anchors and using sods; I have also used the wire mesh method. Almost universally in Alaska, all anchoring devices result in low sur- vival, while the use of sods and plugs results in complete establishment. CONCLUSIONS In areas of environmental stress which might occur in a local area or at extreme limits of the distributional- ecological range, such as in Izembek La- goon for eelgrass or in Texas for Tha- lassia and Halodule, seagrasses appar- ently will not tolerate fixation to iron anchoring devices for planting. In Puget Sound, eelgrass establishes and grows after being affixed to iron anchors and planted as sods or plugs. I recommend using the sod or plug methods because they allow seagrasses to be moved and transplanted while keeping the root-soil interface intact and were more success- ful in the extreme geographical limits of the area as well as the optimum areas. In the optimum ecological area, however, the plug method may be more costly than simply planting detached fragments. The manager should adopt whatever method seems appropriate considering the location, species concerned and sediment type. I prefer the plug method for the following reasons: (1) equipment which removes the plugs from indigenous growth is easily designed; (2) whole meadows of indigenous growth would not have to be greatly perturbed to get planting stock; (3) a great number of plugs could be easily transported; and (4) plugs can be more easily installed than sods. Halodule invaded plots within 1 mo in Boca Ciega Bay, Florida, after denud- ing two large bottom areas within a Thalassia meadow (Phillips 1960). After 5 mo the plots were half full of Halo- dule, but there was no ingrowth of Thalassia. Halodule in the Caribbean seagrass system appears to be a pioneer plant. Thalassia is a climax plant and responds slowly and poorly to severe perturbations such as siltation and change in substrate type. Halodule ap- pears to be stimulated by perturbations. Based on field observations and trans- plants I have made, I suggest using Halodule in restoring an area. Halodule is easily manipulated and will tolerate wide salinity and siltation variation. Very little transplanting, except that by Eleuterius (1974), has been done on dredged materials. Eleuterius had very little success with plantings of Thalassia and Halodule on dredged mate- rials in Mississippi Sound. Since dredged material seems to have charac- teristics different from the soil sup- porting indigenous growth, a plug which keeps the soil -root-rhizome interface intact should have the best chance of success. Also, I recommend the use of Halodule if transplanting were to be done in the South. The specific tech- nique to be employed depends somewhat on the nature of the soil. In Thalassia- Halodule habitats I have seen silts too fine to anchor the plants. Since anchor- ing devices impede survival,! recommend 103 the plug method using the soil as an anchor. With Zostera marina, a variety of transplant methods appear satisfactory. Eelgrass is both a pioneer and a climax species; the species should fulfill more general functions than the two-species seagrass system (Thalassia-Halodule) in the Caribbean. The cheapest method would be to first look at the sediments, and, if they contain a quantity of sand, use detached fragments; however, if they are finer material, use anchoring devices. No large-scaled experiments have been done on transporting and holding of plugs. I suggest taking the plugs with biodegradable plastic tubes in which the cores could be stored until used. If so, the cores with the plugs in them might even be held in the same bay system where the material was taken or where transplant is to be made; however, soil within the plug should be protected from washing. Finally, do not go too far away to find the source of the transplant stock. There is increasing evidence of latitu- dinal ecotypes based on temperature. I suggest using local stocks as much as possible. LITERATURE CITED Addy, C. E. 1947a. Eelgrass planting guide. Md. Conserv. 24:16-17. Addy, C.E. 1947b. Germination of eel- grass seed. J. Wildl. Manage. 11:279. Burkholder, P. R. , and T. E. Doheny. 1968. The biology of eelgrass. Contrib. No. 3, Dept. of Conserva- tion and Waterways, Town of Hemp- stead, Long Island, New York. 120 P- Camp, D. K., S. P. Cobb, and J. F. Van Breedveld. 1973. Overgrazing of seagrasses by a regular urchin, Lytechinus variegatus. Bioscience 23:37-38. Eleuterius, L.N. 1974. A study of plant establishment on spoil areas in Mississippi Sound and adjacent wa- ters. Final Report to U.S. Army Corps of Engineers, 1 July 1971 to 30 Nov. 1974. Gulf Coast Res. Lab., Ocean Springs, Mississippi. 327 pp. Fuss, CM., Jr., and J. A. Kelly, Jr. 1969. Survival and growth of sea- grasses transplanted under artifi- cial conditions. Bull. Mar. Sci. 19:351-365. Kelly, J. A., Jr., C. M. Fuss, Jr., and J. R. Hall. 1971. The transplant- ing and survival of turtlegrass, Thalassia testudinum, in Boca Ciega Bay, Florida. Fish. Bull. 69(2) 273-280. McMillan, C. 1979. Differentiation in response to chilling temperatures among populations of three marine spermatophytes, Thalassia testudi- num, Syrinqodium filiforme, and Halodule wrightii. Am. J. Bot. 66(7):810-819. Orth, R. J. 1975. Destruction of eel- grass, Zostera marina, by the cow- nose ray, Rhinoptera bonasus, in the Chesapeake Bay. Chesapeake Science 16(3):205-208. Phillips, R. C. 1960. Observations on the ecology and distribution of the Florida Seagrasses. Fla. State Bd. Conserv. Mar. Lab., Prof. Pap. Ser. 2. 72 pp. Phillips, R.C. 1972. Ecological life history of Zostera marina L. (eel- grass) in Puget Sound, Washington. Ph.D. thesis, Univ. of Washington, Seattle. 154 p. Phillips, R.C. 1974. Transplantation of seagrasses, with special empha- sis on eelgrass, Zostera marina L. Aqua- culture 4:161-176. " Ranwell, D.C., D.W. Wyer, L.A. Boorman, J.M. Pizzey, and R.J. Waters. 1974. Zostera transplants in Norfolk and Suffolk, Great Britian. Aquaculture 4:185-198. Thorhaug, A. 1974. Transplantation of the seagrass Thalassia testudinum Konig. Aquaculture 4:177-183. Van Breedveld, J. F. 1975. Transplant- ing of seagrasses with emphasis on the importance of substrate. Fla. Mar. Res. Publ. 17. 26 pp. 104 TECHNIQUES FOR CREATING SEAGRASS MEADOWS IN DAMAGED AREAS ALONG THE EAST COAST OF THE U.S.A. Anitra Thorhaug Department of Microbiology University of Miami Miami, Florida 33124 DECISIONS BY GOVERNMENT AGENCIES CON- CERNED WITH RESTORATION OF SEAGRASSES The process of restoration is one of the most hopeful avenues of biology for dealing with man. However, until re- cently, restoration of submerged vegeta- tion was not even considered a possibil- ity and waterfront construction was ex- pected to do a certain amount of irre- versible damage to the adjacent sublit- toral communities. We can no longer afford to have our remaining nearshore submerged resources damaged by develop- ment interests. Therefore, there are two alternatives: (1) save the area immediately adjacent to the coast as a natural strip with no development and build behind this or (2) carefully write permits limiting what developers can do to the submerged land and then enforce these measures. In establishing guidelines for ra- tional restoration of seagrasses (or other plant species) the agency with au- thority immediately encounters questions which it is often not prepared to answer in the early stages, but which are essen- tial for a successful final product. What size area should be restored? What species should be planted? What stand density should be achieved? What time period can be permitted to achieve this density? Site specific information is neces- sary to answer the above questions. The developers' report may not contain this information or may not be credible. The questions of the size area to restore will be a site specific one. Filling valuable waterfront acreage may be judged to warrant from 3:1 to 10:1 (re- stored acres: filled acre ratios). Marina building or navigational channels may possibly be assessed at 1:1 to 3:1. The next question is where the restora- tion will occur. At many sites the exact area to be impacted will be re- stored after the impact has occurred. Other sites will require adjacent areas restored because the original site will not be on land or will be too deep for growth of seagrasses (as in the case of channels). Often a previously damaged site, at some distance from the impacted site, is chosen. In choosing a second site, one should keep in mind suitabil- ity of this site for successful restora- tion (physical, chemical, and geological characteristics), as well as the biolog- ical suitability of this site as a sub- stitute for the original (in terms of nursery area and other considerations). The species to be planted is usual- ly the dominant species found in the preimpact survey. However, there are several exceptions. If the area had previously been impacted by man's activ- ities (such as by drainage canals or other effluents), the original vegeta- tion may have been supplanted by other species. To reestablish the original vegetation, rather than that presently dominant, would usually be preferable unless the water quality had changed so much that the original vegetation could not survive. If there are two or more abundant seagrass species present, one of the following plans can be chosen. (1) Restore several species simultane- ously; (2) restore the. fastest growing species first to stabilize sediment and prepare the area for revegetation; then restore the slower growing species into this matrix; (3) restore only the spe- cies which will return very slowly by natural means and allow the naturally faster growing species to invade; (4) restore only the species needed for a purpose such as a food source or as nursery-stock. Information is often incomplete for such a decision. The decision of which species to plant may have a large effect 105 on the cost of the effort. Neverthe- less, the first decision should be based strictly on the biological rationale and only after this decision is made should economic considerations and compromises be considered. To plant the wrong spe- cies because of economic considerations might do more harm than good. Often the cost considerations will cause a compromise between size of re- stored area and what is planted. In my opinion, if cost is the determining fac- tor, it is better to restore a smaller area correctly than a large area incor- rectly. An exception would be when sed- iment stabilization is the only goal. The density to be achieved and the time period are highly dependent on den- sity of seagrasses currently present in the area. The usual case would be to reestablish the same density within a reasonable time scale of about 3 to 6 yr. If the ultimate density is to be established in a very short time scale (such as months), the cost may become economically unfeasible (Thorhaug and Austin 1977). Note that the question of what density is present is a seasonal consideration in most areas, with late spring peaks and winter lows (Thorhaug and Roessler 1977). Use the highest sea- sonal density in the estimations. Spatially the density of the sea- grass may not be even throughout the area. One might choose an average den- sity of the entire area as the restora- tion goal, but it is more advisable to restore the area in several different densities. If, for instance, a near- shore peat wedge sustains a higher standing crop than offshore sediment, it should be restored in that ratio. The time period for recovery to a given den- sity is a function of the rate of growth of the plants. (Seagrasses spread lat- erally by rhizomal growth.) This rate is highly dependent on species and envi- ronmental conditions and mu£t be envi- ronmentally determined. Best estimates are achieved when a pre-impact growth study has been done in that area. The remainder of this article dis- cusses rationale, historical detail, methods, results, and economic cost anal- ysis of planting seagrasses. More infor- mation can be found in Thorhaug and Aus- tin (1977) and Thorhaug (1977). INTRODUCTION TO THE IMPORTANCE OF SEAGRASSES Although the marine environment is thought to be a place of high productiv- ity, a great portion of the ocean has very low or no productivity. There are a few "hot spots," such as upwel lings which provide a good deal of the total productivity of the oceans. Among these "hot spots" are the seagrass beds which colonize coastal areas of the marine en- vironment. There are 12 genera of angio sperms which have adapted to the marine environment. Eel grass (Zostera marina) and turtle grass (Thalassia testudinum) are dominant, respectively, in the U.S. temperate and tropical to subtropical zones. On the east coast of the U.S. Zostera dominates southward to South Carolina. In Florida and the Gulf of Mexico Thalassia dominates, interspersed with Syrinqodium and Halodule. Seagrasses function in the marine environment in several ways. First, they produce a great deal of organic carbon, much of which enters the food chain both by direct feeding and by detritus. Pro- duction estimates are 300 to 600 g dry weight per meter per year for turtle grass (Thorhaug and Roessler 1977). Secondly, the seagrass provides a shel- ter and place of attachment for many small animals which form the seagrass community. Third, the roots of the sea- grass systems bind the sediment and also provide a baffle for particles so that they enhance the stability of the sedi- ment beneath them, as well as the clar- ity of the water. And lastly, they act as a nutrient and trace metal cycling system for various elements in the marine environment. Recently, there has been a series of studies on the ecology of both the temperate species Zostera and subtropi- cal species Thalassia [Phillips 1960, 1972; den Hartog 1972; Thorhaug 1974; Thayer et al. 1975; McRoy and Helfferich 1979; Thorhaug and Roessler 1977). Sev- eral points of the ecology are important to restoration efforts. The seagrasses are found in the coastal regions of the world; high densities are usually found close to shore, particularly in bays, estuaries, and lagoons. The densest stands of seagrass occur very close to 106 shore and density often decreases sea- ward. This pattern is unfortunate be- cause man's impacts generally occur im- mediately adjacent to the shoreline; if the seagrasses were richer in the off- shore waters the severity of man's im- pact on seagrasses might be lessened. Seagrasses support a rich community of invertebrates and fishes, indeed the Thalassia community is one of the rich- est known in the tropics, rivaling that of the coral reef in diversity and num- bers of animals (de Sylva 1976; Voss 1976; Thorhaug and Roessler 1977). When the seagrasses are removed, the animal community becomes depauperate in those areas (Bader et al . 1972; Roesser et al . 1974; and Thorhaug et al . 1974). Another major point is that after being removed, regrowth of seagrass oc- curs very slowly, especially for Thalas- sia, the dominant species in the sub- tropical and tropical climates. Revege- tation rates vary among species of sea- grasses. Thalassia testudinum has not recolonized in many areas in South Flor- ida and the Caribbean even 50 years after it was removed. NEEDS FOR RESTORATION OF SEAGRASSES Why do we need to restore seagrass- es? First, many marine and estuarine areas throughout the continental United States and Caribbean are increasingly being damaged by man's activities. Very often this damage occurs just adjacent to the shoreline where seagrass communi- ties are present, and years or decades are required for them to return natural- ly to their former condition. The impact is often a combination of effects such as urban runoff, sewage, bul kneading, and others. It is in the public interest to restore thse biologically rich areas for recreation, sport and commercial fisheries, esthetic considerations, and sediment retention (worth $83,000/acre). Second, it is important to restore seagrass into areas directly damaged in the past by building programs (such as filled areas for bridges and causeways or artificial land formations) accom- plished before restoration techniques were available. Thirdly, the seagrasses are one of the few groups of marine plants known to have diseases. In the 1930's, most of the eel grass in the North Atlantic disappeared due to the "wasting disease"; changes in the popu- lations of the associated animals occur- red. The U.S. Fish and Wildlife Service pioneered the restoration efforts in the United States for seagrasses after the wasting disease. However, a solution was never found. It seems highly desir- able to have techniques to replant sea- grasses if this phenomenon occurs again. HISTORY OF RESTORATION OF SEAGRASSES The history of restoring seagrasses is in its infancy, compared to restora- tion of other plant systems, for the same reasons that major work in sublit- toral marine botany is very recent com- pared to that of land botany. Seagrass restoration began almost simultaneous with the development of SCUBA equipment. In 1947 Addy attempted seagrass trans- planting for the U.S. Biological Survey on the Northeast coast of the U.S. as well as between Pacific and Atlantic coasts to recolonize stocks denuded by wasting disease; there were no notable achievements and many transplants fail- ed. In 1960 the Florida State Board of Conservation became concerned about the effect of real estate development in shallow bays. From 1960 to the present the latter organization has attempted transplants mostly with plugs (Fuss and Kelley 1969; Kelly et al . 1971; Phillips 1974, Phillips in this volume; and Van Breedveld 1976). Van Breedvelds' at- tempts with a posthole digger were the most successful. Phillips in 1964 and 1965 conducted reciprocal transplant experiments across tidal zones in Puget Sound and trans- plants between Alaska and Puget Sound (Phillips 1974). An attempt at turfing seagrasses by Ranwell et al . (1974), who transplanted Zostera nol tii and Zostera marina on a pilot trial scale in Norfolk and Suffolk, Great Britain on intertidal mud flats, was successful. The most pro- mising method of large-scale restoration of seagrass communities has been by seed. The first large-scale restoration by seed was done by Thorhaug (1974) in Biscayne Bay, Florida. Thorhaug and Phillips are both presently working on transplantation techniques. The objectives of this section of the paper are to review the techniques 107 by which seagrasses have been trans- planted and the success of some of these techniques, and to describe the problems encountered in restoring seagrasses so that the present state of restoration can be assessed for application of the Department of the Interior. METHODS AND RESULTS The major methods used for trans- planting various species of seagrasses have been (1) plugs, (2) turfs, (3) in- dividual mature plants (turions), and (4) seeds (see Table 1 for data of dis- cussion below). A series of techniques, such as planting seagrasses with various anchors, chemical additivies, and shel- ter, have been attempted in various locations. PLUGS This method involves shoveling or otherwise removing (by a posthole dig- ger) a piece of sediment with seagrass blades, roots, and rhizomes. This piece is transported intact to the recipient site where a second hole is dug and the piece inserted with an anchor or covered with sediment. Problems of this method are that the donor site is damaged, the process requires considerable manual la- bor, and the transplants have only been done interti dally or in very shallow water. In a series of studies, the Florida Department of Natural Resources attempt- ed to plant Thalassia and Halodule in Tampa Bay by plugging (Table 1). Kelly et al. (1971) attempted to correct the efforts of Phi 1 1 ips ' turf work by anchor- ing and sheltering methods (Table 1). Among 120 plants transplanted in a pre- viously dredged canal, only 6 out of 40 of their experimental plugs, and 16 out of 40 in the control area survived. Then Van Breedveld (1976) devised a more suc- cessful technique of plugs using a post- hole digger. Success rates on the Van Breedveld experiments varied from 0-100% depending on the method that he used; however, using the posthole digger with a clump of sediment and planting in rows of three in early spring was the most successful method which had 100% survi- val. (He also concluded that the uses of hormones had not benefited the trans- plants. ) Larkum (personal communication) in Mortons Bay, Queensland, Australia, transplanted plugs of Zostera capricorna by digging plugs and placing them in holes, achieving a fairly high estab- lishment rate. TURFS This method is like sodding a lawn. A piece of sediment and soil is cut out and stacked for transport. Then a shal- low trench, into which the sod is placed, is cut at the recipient site. Phillips in 1960 (Phillips 1974) planted turfs (he called them sods) of Thalassia and Halodule. He had no success with Thalas- sia due to erosion by currents; some success was achieved with Halodule. Ranwell et al. (1974) transplanted Zostera noltii and 1. marina v. angusti- flats near rate of fol ia on mud flats near Norfolk, Eng- land, with a high rate of success. Ini- tial trial examinations were followed by a second larger scale experiment, with the planting of 1,950 turfs in 0.9 ha (2.3 acres) in March. Zostera began growing in the transplanted areas within the next few months and some plants in- creased by 50% within 6 to 7 mo. The survival rate appeared to be about 100% in the first year and about 35% after 2 yr. The Zostera flowered and fruited and spread about two times the original size in the area. Bachman in San Diego (unpublished report) transplanted a small group of Zostera; however, success rates were not reported. Larkum (1976) in Botany Bay, Australia, transplanted Posidonia aus- tral is and Zostera capricorna turfs both in the field and in the laboratory. These did survive although the success rate was not reported. TURIONS Turions are single blade groups with stem and rhizome attached. No at- tempt is made to include the apical mer- istem in a turion. Kelly et al. (1971) reported planting individual turions with the rhizomes removed. Eleven of 60 plants survived. In Washington, Phillips made reciprocal turion transplants which appeared to thrive and produced flowers and seeds as well as initiating new veg- etative growth in the upper zones. 108 CO. .-i 3* 3* CD U"> O ro ro T3 CL-O (1) iSi Oi O CU O ■<- CO T3 Q.T3 E lo E o = U <-* u o X X O csj O CM lO «~ • CM r— CM 1 — >> s- ■— o en O 4- * Q. +J -O CU L- c c c O 10 a -.- CU a (J rti (/> CL >> c c u ra -c !^ 1— CO 2 QJ -*-> ZJ i — (/) o in o cr* ■•-> ro * c • •—i •«- cm U X> O <5 i— u -O t- S- cy i- +-> fQ s- c o o g tfl r- CO ru a i. E O ra i— E O 4- r- O C CU i-H I*-*. Oi lO cu m cu r~- CU Is*. i- en S- Ol CD •-• £33 »-H O IT) i— IDP*. ITJ en en cu 0) T3 t/> XJ . cu a cu r- *t i— z:E QJ O in o c o l/l — ' 0) Hi CO — ' 3 u3 (D n 3 o O 3 n o l/> Q c -I fD t\J OJ OJ OWU1 — ■ -ST O 3 -*. CT CI -s O 1 n 7T c+ 1/1 -% <* L_ — • o -■• a> c Q. 3" T 2 CO to t-» o o n> o a* b4 O 3 fD o -o o -s &* Q. fD t ro fD 3 rt- i/> r+TD Q. fD C O r+(H O. — • zr 3 £ N r-t O 3- 3 rvi f-i 3Z o 1 ft i o O m Q. a i -i O c i ft o t fD a> ft no Plants at lower depths decreased and then died. SEEDS Addy in 1947 planted Zostera seeds but the plants did not grow. Phillips planted 45 Zostera seeds in Puget Sound anchored to iron pipes with rubber bands and had no success, probably because the seeds were transplanted from shallow water to depths deeper than Zostera gen- eral ly grows in the area, indicating that seedlings may have high light re- quirements. One of the most successful seeding methods to date was that of Thorhaug (1974). Roots were gathered by hand from densely fruiting beds in the Caribbean. They were immediately dehisced and the seeds separated from the fruit pods. Seeds were transported back to Miami un- der running seawater conditions. Some of the seeds were kept in a nursery while others were immediately planted. Various growth-promoting chemicals were used. NAA soaks at 10% for 1 hr appeared to have significantly increased root propa- gation of the seedlings. Long soak times and higher concentration of this auxin did not appear to affect the root growth significantly. Planting techniques include plastic 12-cm (5-inch) anchors (with monofila- ment attached to locate the seedlings) secured about each seedling. Two paral- lel corridors (150 by 6 m or 492 by 20 ft) were planted at the Turkey Point Power Plant discharge canal, Biscayne Bay, Florida, in a 9.3-ha (23-acre) area previously denuded of Thalassia and other microphytes by heated effluents. (Offstream cooling was employed at the time of planting, so that thermal efflu- ents were no longer being released.) Previous to thermal discharges, this area had supported a lush meadow of sea- grasses. Seedlings began growing imme- diately upon dehiscing. Up to 10 roots per plant appeared in the first 3 weeks, which enabled the plants to begin to anchor themselves. After 4 mo, one api- cal men stem per plant appeared on 50% of the seedlings. After 5 mo, 89% of the seedlings had apical meristems. Thousands of seeds were planted in mid-September 1973 at various intervals: 0.25, 0.1, and 0.5 m (0.82, 0.33, and 1.64 ft). Leaf growth was vigorous in the months immediately following the planting. New short shoots were sent up from the rhizomal apical meristem after 9 mo, and apical meristems were between 0.3 to 0.5 m (1 to 1.6 ft) (Table 2). Leaf and rhizome growth was vigorous after 8 mo; roots per blade group were 8.6 cm (3.4 in) with a maximum length of roots 14.0 cm (5.5 inches). After 2.5 yr dense areas of Thalassia with 500- 1,000 blades/m2 (46-93 blades/ft2) had developed in the transplanted areas whereas control areas had 0 to 10 blades/m2 (0 to 1 blade/ft2). The per- centage of success was approximately 80%, which was higher than most of the other methods. Twenty-one percent of the plants were missing, and it is estimated that 10% of these missing plants remained in an area of several hundred feet surrounding the planted matrix. Observations showed that the animal community began reestablishing itself almost immediately after the transplants were set. Foraminifera covered the young seedling blades. Fish, certain crusta- ceans, and mollusks moved back into the area. (There has been no quantitative study of animal community reassemblage on any seagrass transplant effort.) The Thalassia planted in a Halodule zone ap- peared to grow more vigorously in the first few months than that planted in a zone of green algae (chiefly Penicillus capitatus), or that planted in a bare peat zone. The major result from this large- scale planting was that plants expanded laterally in a vigorous manner within the first year (rhizome length growing to 0.5 m [1.6 ft] while sending up many short shoots with further blade groups). After 2.5 yr the transplant area was covered with moderately dense Thalassia. We are continuing to study this succes- sion and hope to begin studying the ani- mal community in the restored versus natural and nonrestored areas. A second seedling feasibility study was made in North Biscayne Bay, Florida. Areas included dredge spoil islands; bottoms damaged by sewage pollution, by dredging or general urban runoff; areas of high tidal currents; and areas of shiftinq sand. Feasibility plots of 0.25 w? (2.6 ft2) were planted in fall 111 Table 2. Planted Thalassia testudinum seedling growth (N=130) from late August 1973 to early March 1974 at Turkey Point, Biscayne Bay, Florida (from Thorhaug 1974). % of Tlean length (cm) Maximum length (cm) Minimum length (cm) samples with plants attaining such mean 16.5±4.0 29.6 8.2 100 7.4±4.8 18.0 2.3 54 6.0±5.5 15.1 1.5 18 6.9±8.3 12.7 0.3 4 4.7±2.5 8.2 0.0 89 6.8±2.8 17.0 3.2 100 8.6±2.6 14.0 2.0 100 Longest leaf on primary shoot Longest leaf on second shoot Longest leaf on third shoot Longest leaf on third shoot Rhizome length Longest root length Total number of roots 112 1974 and spring 1975. Survival rates after 6 mo ranged from 0% to 52.5%. Areas of low survival included (1) those with strong tidal currents, (2) those with wave action from boats on the in- tercoastal waterway causing high turbid- ity as well as physical impact to the seedlings, and (3) a submerged dredge island which was eroding with shifting and unconsolidated sediments. Areas most amenable to seedling growth included low energy peaty bottoms or sandy consoli- dated bottoms, especially in areas where a pioneer seagrass species such as Halo- dule or Syrinqodium had already begun to recolonize after the impact (Thorhaug and Hixon 1975). ECONOMIC ANALYSIS The following discussion is from Thorhaug and Austin (1977). The defined objective of planting seagrass is to achieve a given "cover" that will reduce erosion, siltation, and turbidity, and to improve the habitat for marine orga- nisms. Therefore, the cost analysis is in terms of dollar costs to achieve a given cover for a given size area (bot- tom)in a given time period. The costs of the three propagation phases (collec- tion, nursery, and planting) are related to the number of seeds to be handled. The first objective is to determine the number of seeds required for the pro- ject. Five pieces of information are required to estimate the required number of seeds: 1. natural mortality rate of the seeds planted 2. natural growth rate (lateral expan- sion rate) of an individual plant 3. the desired "cover" to be achieved 4. time period permitted to achieve the desired cover 5. size of the area (bottom) to be planted The first two variables are deter- mined by environmental conditions at the planting site (e.g., depth, turbidity, temperature, wave energy level, and type of bottom). The third, fourth, and fifth variables are policy decisions. Presum- ably the desired cover would be similar to cover indigenous to the area as de- termined by what existed in another area with similar conditions or from knowl- edge about what previously existed at the planting site. The time permitted to achieve the cover is an arbitrary policy decision, but it has a signifi- cant influence on the number of seeds that must be planted. The monetary costs of restoration depend on three types of variables. The first set of variables are environmental parameters determining the natural mor- tality and growth rates of the seeds. The second type variables are policy de- cisions relating to the size of the area to be planted and the time period per- mitted to achieve a desired cover of grass. The third type variables relate to the dollar cost of collecting, nurs- ery work, and planting the number of seeds dictated by the first two types of variables. DISCUSSION Tropical and subtropical estuaries are different from that of northern es- tuaries where one can dump a slug of heavy metals or heated effluent on a phytoplankton-based food chain for a few days. In northern latitudes, if one stops dumping the heavy metals or the heated effluent, the photoplankton will renew itself and within a short time the food chain can be reestablished. In con- trast, there are situations in Biscayne Bay, Florida, where the entire food chain has been completely disrupted by man's activities for decades after the disruption ceased. I would also like to point out that the plants involved are the tropical and semitropical grasses. I have previously said that the semitropical-tropical re- gions are more fragile ecosystems than the temperate (Thorhaugh 1976). This fragility is unfortunate because most of the activity in terms of managing estu- aries and nearshore waters has occurred in the temperature zone. The principles gained from northern studies do not al- ways relate to the tropics because the tropics probably are the place where life began. If these tropical organisms, which are geologically very old, were able to migrate out of the tropics, they probably would have; but they are there now because they are less flexible than more northern ones. 113 The best example of intolerance of tropical seagrasses is their response to heated effluents. The best known stan- dards of how much heat could be released (based on experience in temperate zone rivers and offshore waters) were applied to southern Florida. The test was a dis- mal failure. South Florida has a much more fragile ecosystem and organisms could not withstand the same heat in- creases that ecosystems in temperate wa- ters could withstand. Government agen- cies must be particularly careful at- tempting to apply criteria of plant tol- erance to trace metals or dredging in temperate waters to situations in the tropics, reasoning backwards from the more complex temperate to the simple ecosystem of the tropics. I would like very briefly to dis- cuss the alternatives. I disagree with Dr. Phillips' statement ("Creation of Seagrass Beds" in this volume) that we should plant Halodule rather than Thalassia because Halodule grows faster. I feel there are extremely important unknowns yet to be determined about restored Thalassia versus restored Halo- dule before we can responsibly make that statement. For example, does Halodule support the same animal communities that the Thalassia does? Most of the argu- ments about restoration of seagrasses are based on the fact that one is dis- rupting the animal community, the fish- eries potential, or the food web. We have no evidence for this at all in the case of Halodule because there has been no intensive study on the animal commu- nity associated with Halodule. There have been many studies in various areas on the animal community associated with Thalassia. We do know that pink shrimp, the stone crab, and many other desirable animals leave (see Thorhaug and Roessler 1977 for a review or Thorhaug et al. 1973). A second question centers around restoration of Halodule. Is one restor- ing the same animals with a restored Halodule community that one would be if one restored Thalassia? This is a dif- ferent question from what is originally in an untouched community of Thalassia. A third question is, under various con- ditions what is the Halodule root system really going to do to stabilize the sed- iment. Stabilization is one of the effects most desired in restoration, and Halodule does not seem to function as effectively as Thalassia as a sediment stabilizer in regrowing areas. Fourth, there are many areas where Thalassia is just naturally not going to regrow so there must be some effort to reestablish Thalassia. In other places it may reseed over a long period, but can we wait for it to naturally reseed or revegetate? My suggestion might be to plant a mixed community in these semitropical and tropical areas. In such a situation one would not plant as much Thalassia be- cause it is more expensive to plant than Halodule. Halodule would start to form a cover and then one would come back in to restore Thalassia. The cost analyses that have been done on the only scale experiments to date are for Zostera and Thalassia. Zos- tera was restored in England with the free labor of prisoners and students. Thus, the most expensive item, labor, was avoided. This effort really repre- sented a bare minimum. When added up, it was about $2,500/ acre to actually plant 2,000 turfs, so it was a large- scale experiment. However, it should be noted that it was done intertidally, which is always less expensive than in submerged areas. There was no formal economic analysis of this, simply a totaling of expenses. The Florida Board of Natural Re- sources has attempted to restore Halo- dule and Thalassia, for which they have estimated that it is necessary to plant 186,000 plugs of Thalassia per acre in order to get the kind of cover that the Board of Natural Resources desires. Ac- cording to their unpublished estimates (Van Breedveld, personal communication) which use minimum labor costs (which I believe are unrealistic based on other restoration efforts [see Terynk in these proceedings] because you. are not going to find people who will stand for 12 hr, chest deep in freezing water, to plant these seagrasses for $2.30), the cost will be about $50,000 an acre by the plugging method. Our estimates for Thalassia (given in detail by Austin in Thorhaug and Aus- tin 1977), based on about 7,000 Thalas- sia having been planted in about 15,000 m2 using the seeding method, range at the moment (depending on many factors, 114 and without mechanization) between $2,000 and $8,000 an acre after 3 to 4 yr. Planting seagrasses is not cheap. We are working now on mechanization, growth-promoting hormones, and fertil- izers, things that should speed growth, lessen mortality, and lessen the cost. ACKNOWLEDGMENTS This work was sponsored by ERDA, Grant number ATE-40 and Sea Grant(NOAA). LITERATURE CITED Addy, C.E. 1947a. Eelgrass planting guide. Md. Conserv. 24:16-17. Addy, C.E. 1947b. Germination of eel- grass seed. J. Wildl. Manage. 11: 279-480. Bader, R.G., M.Roessler, and A.Thorhaug. 1972. Thermal pollution of a trop- ical marine estuary. Pages 245-251 in Marine pollution and sea life. Fishing News Ltd. Surrey, England. den Hartog, C. 1972. The seagrasses of the world. Verh. Konin, Nderl. Acad. Wetens. Natuuk 59(l):l-275. de Sylva, D.P. 1976. Fishes of Biscayne Bay, Florida. Pages 181-190 vn A. Thorhaug, ed. Biscayne Bay: past, present, future. Univ. Miami, Florida. Eleuterius, L.N. 1975. Submergent veg- etation for bottom stabilization. Pages 439-456 j_n Estuarine research Vol. II. Academic Press, New York. Fuss, CM., Jr., and J. A. Kelly. 1969. Survival and growth of sea grasses transplanted under artificial con- ditions. Bull. Mar. Sci. 19:351- 365. Kelly, J. A., Jr., M. Fuss, and R. Hall. 1971. The transplanting and sur- vival of turtle grass, Thalassia testudinum, Boca Ciega Bay, Flor- ida: Fish Bull. 6(2):273-280. Larkum, A.W.D. 1976. Aust.J.Mar.Freshw. Res. 27(l):217-222. McRoy, C.P., ana C. helfferich. 1979. Seagrass ecosystems: a scientific perspective. Marcel Dekker, New York. Phillips, R.C. 1960. Observations on the ecology and distribution of the Florida seagrasses. Fla. State Bd. Conserv., Mar. Lab. Prof. Pap. Ser. 2. 72 pp. Phillips, R.C. 1972. Ecological life history of Zostera marina (eel- grass) in Puget Sound, Washington. Ph.D. Thesis. Univ. Washington, Seattle. 154 pp. Phillips, R.C. 1974. Transplantation of seagrasses with special emphasis on Zostera marina, L.Aquaculture 4(3): 161-176. Ranwell, D.S., D.W. Wyer, L.A. Boorman, J.M. Pizzey, and R.J. Waters. 1974. Zostera transplants in Norfolk and Suffolk, Great Britain. Aquaculture 4(3):185-98. Roessler, M.A., G.L. Beardsley, and R. Smith. 1974. Benthic communities of Biscayne Bay, Florida. Univ. Miami Sea Grant Coastal Zone Man- age. Bull. 13. 19 pp. Thayer, G. , D. Wolfe, and R.W. Williams. 1975. Man's impact on seagrass ecosystems. Am. Sci. 63 (3):288- 296. Thorhaug, A. 1974. Tranplantation of the seagrass Thalassia testudinum Koeniq. Aquaculture 4(3~):177-183. Thorhaug, A. 1976. Tropical macro-algae as pollution indicators. Micro- nesica 12(l):49-63. Thorhaug, A. 1977. Restoration of major plant communities in the United States. Environ. Conserv. 3(5): 50-54. Thorhang, A., and C.B. Austin. 1977. Restoration of seagrasses espe- cially around the United States with economic analysis. Environ. Conserv. 3(4) :259-267. Thorhaug, A., and R. Hixon. 1975. Reveg- etation of Thalassia testudinum in a multiple stressed estuary, North Biscayne Bay, Florida. Pages 12-27 vn R.R. Lewis, ed. Second annual congress on restoration of coastal vegetation in Florida. Hillsborough College Press, Tampa, Florida. Thorhaug, A., and M. Roessler. 1977. Seagrass community dynamics in a subtropical estuarine lagoon. Aqua- culture 12:253-277. Thorhauq, A., D. Segar, and M. Roessler. 1973. Impact of a power plant on a subtropical estuarine environment. Mar. Poll. Bull. 4(11) :166-169. Van Breedveld, J. 1976. Transplanting 115 of seagrasses with emphasis on the Wanless, H. 1976. Geoloaic setting and importance of substrate. Fla. Mar. recent sediments of the Biscayne Res. Publ._ 126, St. Petersburg, Bay Region, Florida. Pages 1-31 jn A. Thorhaug, ed. Biscayne Bay: past, present, future. Univ. Miami, Miami, Florida. Florida. 25 pp. Voss, G.L. 1976. Invertebrates of Biscayne Bay: past, present, future. Univ. Miami, Florida. 116 COASTAL HABITAT DEVELOPMENT IN THE DREDGED MATERIAL RESEARCH PROGRAM Hanley K. Smith1 Waterways Experiment Station U.S. Army Corps of Engineers Vicksburg, Mississippi 39180 INTRODUCTION The Dredged Material Research Pro- gram (DMRP) is being conducted at the Corps of Engineers Waterways Experiment Station at Vicksburg, Mississippi. As manager of the Habitat Development Pro- ject, I plan, manage, and carry out the habitat development aspects of DMRP. Realizing your differing levels of ac- quaintance with the program, I will pre- sent an overview of the DMRP and then concentrate on the habitat development aspects. See Table 1 . Dredging the navigable waterways of the United States is important to the Nation's economy and vital to creating and maintaining the channels, harbors, and associated facilities that accommo- date the large volume of domestic and foreign waterborne commerce. The primary purpose of most of this dredging is to maintain a designated channel or area at a predetermined water depth by removing bottom accumulations. These accumula- tions are the result of discharges and erosion, transport, and deposition often influenced by storms and flooding and augmented by man's actions. Principal responsibility for navi- gation facility maintenance and improve- ment is vested in the Corps of Engi- neers. With its own equipment or by con- tract, the Corps periodically dredges thousands of kilometers of waterways and hundreds of commercial port facilities and small boat harbors assigned to it by Congress for maintenance. The annual costs of waterways maintenance are approaching $250 million and annual maintenance dredging volumes exceed 214,100,000 m3 (280,000,000 yd3). The 1 This same report was presented at the 42nd North American Wildlife Conference. new work portion approximates $50 mil- lion and 61,200,000 m3 (80,000,000 yd3) annually. The large volumes of dredged mater- ial often present extraordinary disposal problems. In the past, economics was the almost exclusive criterion used in de- termining disposal location and method. However, during the past decade, envi- ronmental impact has become a signifi- cant criterion and, from a practical standpoint, the one controlling many dredging projects. Although limited, some procedures and technology do exist and are being used to avoid or reduce adverse environmental impacts; however, the real problem lies elsewhere. With few exceptions, the state of knowledge and site-specific studies have failed to provide definitive information on what constitutes an adverse impact caused either by nature of the material or the mode of disposal. Hence, opinions and actions regarding dredging and disposal often are based almost entirely ofi fears of unknown consequences rather than facts; decisionmakers have had no way to quantify effects or determine alterna- tives for rational solutions to pro- blems. To better depict the scope of the dredging effort and its potential envi- ronmental impact throughout the conti- nental United States, it is necessary to understand that annual dredging require- ments by Corps Districts vary consider- ably. The largest volume, which is nearly 151,470,000 m3 (198,100,000 yd3), is dredged in the Lower Mississippi Val- ley Division, while one of the smallest requirements is the New England Divi- sion's 1,836,000 m3 (2,401,000 yd3). Dredging costs, however, present an en- tirely different picture. Although the national average cost per cubic yard is still well under $1, geographically the 117 Table 1. Dredged Material Research Program, Technical Structure. Project/Task Environmental Impacts and Criteria Development Project 1A Aquatic Disposal Field Investigations IB Movements of Dredged Material 1C Effects of Dredging and Disposal on Watet Quality I D Effects of Dredging and Disposal on Aquatic Organisms IE Pollution Status of Dredged Materia] 2D Confined Disposal Area Effluent and Leachate Control Habitat Development Project 2A Effects of Marsh and Terrestrial Disposal 4A Marsh Development 4B Terrestrial Habitat Development 4E Aquatic Habitat Development 4F Island Habitat Development Disposal Operations Project 2C Containment Area Operations 5A Dredged Material Densification 5C Disposal Area Reuse 6B Treatment of Contaminated Dredged Material 6C Turbidity Prediction and Control Productive Uses Project 3B Upland Disposal Concepts Development 4C Land Improvement Concepts 4D Products Development 5D Disposal Area Land-Use Concepts Objective Determine the magnitude and extent of effects of disposal sites on organisms and die quality of surrounding water, and the rate, diversity, and extent such sites are recolonized by benthic flora and fauna. Develop techniques for determining the spatial and temporal distribution of dredged material discharged into various hydrologic regimes. Determine on a regional basis the short- and long-term effects on water quality due to dredging and discharging bottom sediment containing pollutants. Determine on a regional basis the direct and indirect effects on aquatic organisms due to dredging and disposal operations. Develop techniques for determining the pollutional properties of various dredged material types on a regional basis. To characterize the effluent and leachate from confined disposal facilities, determine the magnitude and extent of contamination of surrounding areas, and evaluate methods of control. Identification, evaluation, and monitoring of specific short-term and more general long-term effects of confined and unconfined disposal of dredged material on uplands, marsh, and wetland habitats. Development, testing, and evaluation of the environmental, economic, and engineering feasibility of using dredged material as a substrate for marsh development. Development and application of habitat management methodologies to upland disposal areas for purposes of planned habitat creation, reclamation, and mitigation. Evaluation and testing of the environmental, economic, and engineering feasibility of using dredged material as a substrate for aquatic habitat development. Investigation, evaluation, and testing of methodologies for habitat creation and management on dredged material islands. Development of new or improved methods for the operation and management of confined disposal areas and associated facilities. Development and testing of promising techniques for dewatering or densifying dredged material using mechanical, biological, and/or chemical techniques prior to, during, and after placement in containment areas. Investigation of dredged material improvement and rehandling procedures aimed at permitting the removal of material from containment areas for landfill or other uses elsewhere. Evaluation of physical, chemical, and/or biological methods for the removal and recycling of dredged material constituents. Investigation of the problem of turbidity and development of a predictive capability as well as physical and chemical control methods for employment in both dredging and disposal operations. Evaluation of new disposal possibilities such as using abandoned pits and mines and investigation of systems involving long-distance transport to large inland disposal facilities. Evaluation of the use of dredged material for tire development, enhancement, or restoration of land for agriculture and oilier uses. Investigation of technical and economic aspects of the manufacture of marketable products. Assessment of the technical and economic aspects of the development of disposal areas as landfill sites and the development of recreation-oriented and odier public or private land-use concepts. NOTE: This technical structure reflects the second major program revaluation made after the second full year of research accomplishment and is effective as of August 1975. 113 cost varies over a wide range and is rising steadily. The dredging and dis- posal cost is highest in New England, nearly $5/yd3. The cost in the Lower Mississippi Valley is lowest, just under SCMO/yd3. Note that this is an inverse situation from the total amounts of dredged material listed above. Thus, the scope of the problem, in an economic context, does not correlate proportion- ately to the quantities. In some loca- tions, the cost has risen to over $10/ yd3. The tremendous range of dredging and disposal costs is due to several factors. A large percentage of dredged material is fine-grained sediment and, as a consequence, it is a natural sink for contaminants resulting from urban and agricultural runoff, domestic and industrial sewage, and other polluting sources. Sediments dredged from water- ways once were most commonly disposed of in open water or on marshes. But now, because of some known consequences of dredging and disposal, and a concern over the unknown consequences of such actions, the general practice has been to confine contaminated materials on land behind dikes. In many areas, this has increased the cost of the operation by a factor of at least 10. In 1970, Congress passed legisla- tion that called for an interim 10-yr program of building confined disposal facilities to retain all contaminated material from the harbors in the Great Lakes. With the anticipated cost of this program for this one region of the U.S., estimated at approximately a quar- ter of a billion dollars, Congress rec- ognized a need to understand far better what are truly the environmental effects of dredged material disposal. Conse- quently, the same legislation that man- dated the Great Lakes diking program in- cluded authorization for a comprehen- sive, nationwide research program to provide much needed answers. Hence, the DMRP was established as a multi-objec- tive research plant that would require 5 yr and $30 million to complete. The program began in 1973 and was completed in March 1978. Insofar as environmental effects are concerned, the DMRP is as concerned with disposal in upland and wetland areas as it is with open-water disposal. It is concerned with the productive use of both the dredged material and the disposal sites. Principal emphasis is on marsh and habitat development as the most promising productive or beneficial disposal alternatives. Realizing that confined land disposal is a viable al- ternative, the DMRP is concerned with improving the effectiveness, acceptance, and environmental compatibility of con- fined disposal and making it more econo- mical. The program has been divided into four project areas: the Environmental Impacts and Criteria Development Project, the Disposal Operations Project, the Productive Uses Project, and the Habitat Development Project. I will briefly touch on the first three projects and then proceed to a more detailed discus- sion of the Habitat Development Project. ENVIRONMENTAL IMPACTS AND CRITERIA DEVELOPMENT PROJECT The Environmental Impacts and Cri- teria Development Project is the focal point for research about the effects on water quality and aquatic organisms of both land and open-water disposal as well as land containment of dredged material . Aquatic Disposal Field Investiga- tions are a principal concern of this project. Four major field investigations of the physical, biological, and chemi- cal impacts of open-water disposal are being conducted in the Pacific Ocean off the mouth of the Columbia River, Oregon; the Gulf of Mexico off Galveston, Texas; Lake Erie off Ashtabula, Ohio; and an estuarine site near the Duwamish Water- way in Elliott Bay, Seattle, Washington. To date, the baseline research and con- trolled disposal investigations are com- pleted and the post-disposal monitoring is currently underway at all four sites. Another concern of this project is the short- and long-term movements of dredged material in open water. A math- ematical estuarine dispersion model has been developed and is presently being field verified. The objectives of the field study are to quantitatively define the physical processes by which dredged material released from a barge, hopper- dredge, or pipeline is conveyed to, and 119 emplaced upon the bottom at selected sites and how the data compare with mathematical simulation outputs from the model . Short-term, high-intensity labora- tory elevations have been completed to determine the effects of contaminated dredged materials on the water column. Results of these laboratory studies show that acute chemical effects on the water column range from insignificant to com- pletely nonexistent. Much of the con- troversy associated with mobilization of a wide range of contaminants is unfound- ed and was not shown to occur in a broad range of sediment and water conditions. Only ammonium, iron, and manganese were shown to be released to the water column in quantities significantly greater than background. These findings are being tested in the field investigations which I previously mentioned. Laboratory tests on the chemical stability of sediment water systems can- not be directly related to the response of organisms. In studying the response of selected organisms to the physio- chemical conditions, we have found that many of the projected impacts associated with open water disposal were unfounded fears. However, this task has delineat- ed certain areas of significant ecologi- cal concern. Vertical migration investigations have shown that representative bottom- dwelling organisms have a significant ability to migrate upward through cover- ings of various depths of dredged mate- rial. Those organisms most severely impacted are sand-dwelling organisms that have a clay-like sediment deposited on them, and mud-dwelling organisms covered with sandy dredged material. This indicates the desirability of choosing a disposal site. Heavy metals availability to ben- thic organisms from the solid phase por- tion of dredged material is currently under study. Preliminary results using grossly contaminated Houston Ship Chan- nel sediments indicate a general toxic- ity of the sediments, but uptake of a wide selection of heavy metals was not occurring. The final task area that I am going to mention in this project is concerned with the environmental impact created by placing dredged material in containment areas, as well as sanitary landfills and quarries that could be disposal areas under some of the various beneficial use concepts being explored. The main goal is to determine if contaminations intro- duced into these confined areas through dredging and disposal will be immobi- lized, with negligible long-term re- lease, or be discharged in environmen- tally unacceptable quantities with the effluent or leachate. Effluent is re- leased almost continuously for several weeks during the filling of most dispos- al areas. This effluent could result in chronic discharge problems in confined bodies of water. Following filling of a land disposal area, short- or long-term leaching could potentially mobilize chemical constituents from the dredged material and threaten surface and groundwater quality. DISPOSAL OPERATIONS PROJECT Most of our engineering or opera- tions research effort is being conducted by the second project, the Disposal Operations Project. This project is pri- marily concerned with improving the ef- ficiency of dredged material disposal. Several aspects of this project include dike design and improvement of dewater- ing techniques, landscaping of disposal sites, silt curtain performance, and treatment of contaminated, dredged mate- rial. Because participants interests at this workshop are primarily biological, I have elected to devote little time to •_ project. PRODUCTIVE USES PROJECT The basic philosophy for the third project of the DMRP, the Productive Uses Project, is to develop new or innovative disposal methods, primarily on land, to provide disposal alternatives which de- rive maximum value from the resource potential of dredged material. To pro- vide the information necessary, the Pro- ductive Uses Project is responsible for investigating viable productive uses of dredged material, or where environmental considerations preclude its use, the evaluating of new concepts for disposal in upland areas. Specifically, the pro- ject is divided into the four tasks. The tasks are upland disposal of dredged 120 material at long distances from the dredging project; the use of dredged material for land enhancement whether as a landfill material or as a soil; the development of products such as shrimp, lawn sod, or horticultural crops grown in dredged material; and, finally, with the development of disposal areas into recreational or commercial sites. A major effort in this project is to identify, in a categorical sense, po- tential disposal areas at remote inland locations some distance from the dredg- ing operations; to examine components of an inland transport system; and to as- sess environmental, technical, economic, and institutional factors associated with upland disposal. An example would be the use of abandoned pits or quar- ries, both as a disposal option and a significant land use benefit. The concept of the beneficial use of dredged material for land improve- ment, especially in agriculture, appears promising. Under this task the physical and chemical qualities of dredged mate- rial as a soil base or amendment will be evaluated. Another potential use of dredged material is for sanitary land- fill cover. Presently sanitary landfill cover can be purchased for up to $6.54/ m •* ($5/yd 3 ). in some cases, the use of dredged material would be economically competitive. The Productive Uses Project is also exploring possibilities of manufacturing marketable products of commodities from dredged material or using disposal sites for similar activities. Products manu- facture (e.g., ceramics or bricks) has not proven feasible on a scale which could significantly affect large quanti- ties of dredged material. In some iso- lated cases the manufacture of a syn- thetic aggregate may be worthwhile. A recently completed study dealt with the feasibility of using disposal areas for growing land sod or horticul- tural products. The study found that there is a considerable demand for such products, particularly near large urban centers, and in some cases this may be a feasible alternative. The potential for mariculture of shrimp and other commercially valuable species is being investigated by Dow Chemical Company. Dredged material was transferred to two 0.10-ha (0.25-acre) ponds located within Dow's facilities at Freeport, Texas, and about 0.3 m (1 acre) of material was placed in each pond. Two similar ponds received no material and were designated control ponds. After an initial fertilization to stimulate algal growth, about 10,000 juvenile shrimp were placed in each of the four ponds. No other food was added throughout the experiment. Previous shrimp mariculture work indicated that the survival rate should be 50% or greater. All four ponds were harvested after 3 mo. Over 75% of the shrimp survived, and those raised on dredged material were significantly larger than those in the control ponds. The disposal area land-use concepts task is assessing the technical and eco- nomic aspects of developing disposal areas as landfill sites. We have also included the development of recreational areas and other public or private land- use concepts. HABITAT DEVELOPMENT PROJECT The final project, the Habitat De- velopment Project, is divided into five tasks: (1) the effects of dredged mate- rial disposal on marsh and terrestrial habitat, (2) marsh development, (3) ter- restrial habitat development, (4) aquat- ic habitat development, and (5) island habitat development. These tasks are closely related and often grade natural- ly into one another. The basic emphasis of these tasks can be summarized in two main objec- tives: to determine the environmental impact of habitat development and to evaluate habitat development as a dis- posal alternative. Major emphasis is being placed on the first task, determining the effects of disposal in marsh and terrestrial areas. To a larger extent, all of the work in the Habitat Development Project relates to this task. The environmental impacts of dredged material disposal and habitat creation at all of our field sites are being carefully evaluated, and this information will form the basis of most of our findings and conclusions relative to impact assessment. In addi- tion to the field studies, much of the ongoing work in impact assessment is directly related to heavy metal and 121 nutrient cycling research which will be discussed under the marsh development task. See Figure 1 . A typical example of research being conducted in this task area is a study at St. Simons Island in Georgia, to de- termine the effects of smothering on marsh grasses. In this study, Spartina alterniflora, the dominant salt marsh grass, is being subjected to disposal of sand, silt, and clay dredged material at controlled depths from 7.6 cm (3 inches) to 1 m (3.3 ft). The experiment will be repeated during the dormant, growing, and reproductive seasons to interpret seasonal impacts. The impact of these disposal applications will be determined by changes in marsh productivity and succession. The development task is the princi- pal thrust of the Habitat Development Project. We have, or have attempted, field studies at Branford, Connecticut; in the James River, Virginia; in the Po- tomac River near Washington, D.C.; on the coast on the Bolivar Peninsula, Texas; in San Francisco Bay; at Miller Sands in the Columbia River; and at Grays Harbor, Washington. The field site at Branford, Con- necticut, was terminated last October. We had intended to develop a 3.2-ha (8-acre) marsh as an extension of the existing marsh, thereby disposing of 30,600 m3 (40,000 yd3) of fine-grained, contaminated dredged material. From its conception, this project met with sub- stantial local opposition, and, despite numerous safeguards and assurances, we were never able to gain community ap- proval. The most common concern voiced by opponents was that the newly created marsh might, because of its experimental nature, threaten real estate values in the area. Other concerns were odor, dan- ger to neighborhood children, and mos- quitoes. Repeated delays finally placed the project in an untenable time frame which resulted in its cancellation. A 5.6-ha (14-acre) marsh develop- ment site in the James River, Virginia, was built last year by taking 53,550 cm3 (3,207 inches3) of contaminated fine- grained dredged material from the navi- gation channel and confining it behind a hydraulically placed sand dike. We had intended experimental planting on this site, but Mother Nature was more effi- cient, and by July of the first growing season, the area had naturally vege- tated. Fortunately, a desirable mix of wetland species developed including arrow arum (Peltandra virginica), pick- erel weed (Pontederia cordata), and arrowhead (Sagittaria spp. ). The main thrusts of research at the James River site now involve the potential uptake of contaminants by plants growing on the dredged material and documentation of the biological productivity of the site. These studies should result in important findings regarding the environmental im- pact and feasibility of marsh develop- ment as a disposal alternative. We have a potential marsh develop- ment site quite close to Washington, D.C. at Dyke Marsh on the Potamac just south of Alexandria. This area was extensively mined for gravel in the 1930's, and during these mining opera- tions a considerable portion of Dyke Marsh was destroyed. Ownership of the area has since passed to the Government, and the National Park Service has a Con- gressional mandate to restore Dyke Marsh to its original configuration. We have entered into a cooperative study with the Park Service, the Corps' Baltimore District and the Fish and Wildlife Ser- vice to evaluate the feasibility of us- ing dredged material from the Potomac River as a substrate for marsh estab- lishment at this site. The marsh will be restored by plac- ing approximately 229,500 m3 (300,000 yd3)of dredged material, covering 11.3 ha (28 acres) at an intertidal elevation behind a sand dike. The feasibility phase of this study will be completed May 1976. If the project proves feasi- ble, and agency and public support is obtained, we will proceed to the de- tailed design phase. If this project is completed, approximately 10% of Dyke Marsh will be restored to near-original conditions. A former dredged material island at Buttermilk Sound on the Georgia coast was selected for study. We have estab- lished a 1.2-ha (3-acre) salt marsh at this site by shaping a mound of dredged material so that approximately half was intertidal. More than 800 plots have been established at this site to test the survival and productivity of eight plant species at three tidal elevations, under four fertilizer regimes. This project is also designed to obtain data 122 POND 3 NOTT ISLAND BRANFORD HARBOR NEW JERSEY NORTH CAROLINA O MARSH DEVELOPMENT A TERRESTRIAL DEVELOPMENT < to CO < _i ID CO CO < a: CD — < < X on o o z. z < < LU — PQ Q CQ Z >— — oc < o o < < on o < o o o — i o < en LU CO CO < on CD Q on o c_> < on LU o CO CO < on CD o o o CO CO < ~. < on x CD co _i < < CD LU LU OS Z. < CO < On < CO < o o CO co 2 _1 LU »— 1 «s ■N t— i "\ < Q h- < < 1- CO "\ CO •— 1 •—I co LU < ~\ -\ >- CO CO > > Z < < o CO CO o o — 1 0d On o < < o on 1- LU LU on _J _J on CD ct 1— 1- o < < o z. < CO co < X X < < Q_ o o h- l- s: •z. CO M M O h- >- X ro CM E £ 0 3 i -a E c u n! >• s w 3 o -a II ^ - - ° E <^ c °* S « ■" a »« zl2 3 141 Recycling of nutrients is dependent on the structure of the food web. Fig- ure 2 illustrates a food web which would be appropriate for almost any coastal zone with some type of macroscopic plants. Grazers consume perhaps 10% of the macroscopic plants, and 90% of them are degraded by bacteria and fungi. The elements in the tissues of the plants, such as phosphorus and nitrogen, are re- cycled primarily through death and de- generation. It may not be generally ap- preciated that the obvious grazer does not consume most of the grass. The graz- ers in forest and grassland rarely get 10% of the crop. Most of it really fol- lows the detritus route, which is much less obvious. We all see large animals and small ones; we do not see the bacte- ria. Nevertheless, they are the degrad- ers of much of the total material, and move it through particulate and dis- solved pathways. The end result is the recycling of such elements as nitrogen and phosphorus into inorganic forms which are available to plants. Although it may not be wholly de- served, phosphorus has received much attention in recent years. The classical view of the phosphorus cycle still has good circulation in textbooks and in the scientific community. This view is one of seasonal changes in the abundance of phosphorus in the water. The concentra- tion of phosphorus in the water increas- es during the winter in the temperate zone. It is utilized by aquatic plants in the spring when the weather gets warm and days longer. Then, there is a summer crash when the supply of nutrients be- comes depleted. Production presumably slows down for that reason, staying at a relatively lower level through fall and winter. This classical view of the annual cycle of abundance of phosphorus was developed 50 yr ago when it was first possible to measure phosphorus chemical- ly by colorimetric methods. In the 1950 ' s , people began to use 32P in aquatic research. They quickly found that phosphorus was more mobile than they had realized. While observers had been thinking in terms of seasonal changes in abundance, in fact, the standing stock of phosphorus in any water body was usually replaced every few days. In some lakes it was replaced every few minutes (Rigler 1956). The seasonal cycle that people had been see- ing and measuring chemically was really a shifting equilibrium point, superim- posed on a rapid recycling seen only by labeling the pool with a radioactive tracer. Now that we are aware of this and use tracer methods, we knew that there is a great deal of recycling of phosphorus. The high productivity of coastal systems, in many cases, depends heavily on recycling, rather than on a continued supply of new phosphorus into the sys- tem. This has been examined in many eco- systems including the coastal upwel lings off Peru. Dugdale and Goering (1967) have estimated that 50% of the nitrogen used is recycled and 50% is newly up- welled. For the coastal waters off Georgia, Haines (1975) estimated that 95% of the nitrogen was recycled. I am sure the same is true of phosphorus. Recycling is a major factor in continu- ing productivity of many coastal ecosys- tems. Figure 3 is a simplified version of how I view the phosphorus cycle in a shallow coastal system where sediments are present. In the classical view, bac- teria are generators or remineralizers of phosphorus, but nobody has yet suc- ceeded in finding these bacteria in nat- ural waters. We now think that the major role of bacteria really is scavenging phosphorus. Bacteria take phosphorus wherever they can get it. They may take it from food material or they may take it from the pool of phosphorus in the water. In fact, the bacteria are compet- ing with the phytoplankton for a common source of dissolved phosphate, and the bacteria compete very well and will get some of the phosphate away from the phy- toplankton. But the life cycles of bacteria are very short. They die o-r they are con- sumed by other organisms. The turnover time of bacteria is probably a matter of one day in most systems. So the result is that phosphate moves through both phytoplankton and the bacteria to fil- ter-feeding consumers and benthic- deposit feeding consumers. These con- sumers excrete the phosphate since most of what they consume must be utilized to supply energy. Most of the phosphorus in the organic matter that they consume 142 PHYTOPLANKTON MACRO-ALGAE AND SEA GRASSES \ ^ I \ FILTER FEEDERS AND DETRITUS AND ^ *4 GRAZERS PLANKTONIC GRAZERS MICROORGANISMS PREDATORS DEPOSIT FEEDERS t PREDATORS BENTHIC MICROFLORA Figure 2. Generalized food web for the coastal zone, showing the relationships of the detritus food chain and the grazing food chains. FILTER FEEDERS BACTERIA AND t PHYTOPLANKTON ^ DETRITUS HPOZj- ^^ (water) _ S / ^^GRAS! HP04~ / __-*► ■— - macro-algae (sediment) Figure 3. Generalized compartmental model of the flux of phosphorus through coastal zone ecosystems. 143 is excreted as phosphate. By the time food has gone through the first level of carnivores, 90% or more of the phosphate has been excreted. The rapid recycling that we find with tracers is not the production of phosphate by bacteria, but rather the rapid consumption and excre- tion of most of it back as phosphate. There is a substantial experimental basis for this view of the recycling of phosphate (Pomeroy 1970). Microscopic organisms with short life spans tend to be the important organisms in terms of recycling nutrients as well as in expen- diture of energy. The larger organisms, although they have other valuable attri- butes, are not major recycling organisms in terms of moving phosphorus or other elements around in the ecosystem. Fall- out of organic matter carrying phospho- rus to the bottom is a potential sink taking phosphorus out of circulation. If the fallout is not very far, phospho- rus does not get out of the system. What reaches bottom will go into the mouths of hungry organisms or into the bodies of bacteria and get back into the system again. The recycling of elements in shallow water tends to be more complete than in the deep ocean. Also, there is a physicochemical equilibrium between phosphate in the water and the sediments, especially clay sediments which adsorb phosphate on the surfaces of the platelets of clay. There will be many times more phosphate on the clay than in the water when there is an equilibrium. The equilibrium establishes itself in a matter of minutes and is a continuing process, going on all the time. To some extent, this tends to be a stabilizing influence on the amount of phosphate in the water (Pomeroy et al. 1965). In the real world, the clay is not fully suspended, so the equilibrium is only realized to the extent that there is interaction between water and clay. The clay is probably more important in another way. Plants are growing in it, and they are getting phosphate out of the interstitial water. There is a continual pumping of phosphate out of the sediments by the grass; then, when the grass dies, it is degraded and phos- phate goes into the water. So, recycling between water and sediments is driven by the growth of marine grass. As it grows, the grass also leaks, and Reimold (1972) studied the rate at which it loses phos- phate. The washing of the grass by the tide removes about as much phosphate as is actually incorporated in the annual growth of grass, so the amount of phos- phate pumped from the sediment may be twice as much as that incorporated by growth. There is also inflow of phosphorus from rivers to coastal waters, which supplies a portion of the annual re- quirement of plant populations in the coastal zone. This is a very indirect contribution and its importance is not clear. Phosphorus coming down a river is not going directly to plants. For phytoplankton or even kelps the effect of phosphorus carried by rivers may be more immediate than in a system with intertidal plants. In a salt marsh, for example, phosphorus recycling is much more important in the short term than input from rivers. In terms of geologi- cal time, rivers are important. We often overlook the fact that phosphorus comes from the ocean as well as the rivers. In fact, probably more of the phosphorus that cycles through the coastal zone comes from the ocean. There are a number of mechanisms that bring phosphorus in from the ocean, such as the upwel lings off Peru and South Africa, that are well known and very dramatic. There is a less known type of upwel ling along the edge of the conti- nental shelf of the U.S. Atlantic coast. Periodically, the Gulf Stream washes up on the shelf. The idea that nutrients move toward shore across the continental shelf was originally proposed in a math- ematical model by Riley (1967). His mod- el showed that nutrients had to go in- ward across the shelf with the inner part of the shelf being supplied with nutrients by the ocean. What the physi- cal oceanographers are beginning to tell us now would verify this, that indeed the ocean is of major importance in sup- plying nutrients to the coastal zone. In any case, phosphorus is not an element that is limiting in coastal zone water. There is plenty of it around, except in the cleanest tropical situa- tions, such as the Florida Keys or Ha- waii; those are the only situations in which phosphorus might be a limiting factor. 144 Nitrogen has many similarities to phosphorus and some differences in its cycles. One of the biggest differences is that the main reservoir of nitrogen is the atmosphere rather than planetary rocks. As nitrogen gas, it is available only through nitrogen-fixing organisms. The nitrogen fixers are bacteria and blue-green algae. So a very limited range of organisms is involved in nitro- gen fixation. Other organisms depend upon the continuing fixation of nitrogen by a taxonomically limited group. Nitrogen fixers are widespread; many are in the coastal zone. We have always thought of them as being present in soil; however, they are present in much of the ocean as well. There are blue-green algae in the tropical and sub-tropical oceans. We now know that there are abundant blue-green algae on coral reefs, and there is active nitro- gen fixation there. There are blue- green algae in salt marshes, and there is nitrogen fixation there as well. In most coastal systems which we have exam- ined with modern methods, we have found nitrogen fixation. This does not neces- sarily mean that nitrogen is abundantly available in the coastal zone because there is denitrification going on as well. The important point about denitri- fication is it is done by an even more limited group of specialists. These are obligate anaerobic bacteria. Denitrifi- cation occurs only where there is an anaerobic environment, notably in sedi- ments such as those found in marshes. A stagnant estuary, with the bottom water depleted in oxygen, might have some de- nitrification. Much of the denitrifica- tion is probably associated with the bottom of the continental shelf or with the estuaries. Nitrogen also goes through the same kind of food web cycle as phosphorus. With a few exceptions, nitrogen is accum- ulated by bacteria and plants. It is consumed and regenerated, and most of the regeneration is in the form of am- monia, so there is a very rapid cycle of ammonia much like the rapid cycle of phosphate. At any one time, there is very little ammonia in the system be- cause ammonia is, for most plants, the preferred form. It is the most reduced form and, therefore, the energetically optimal form. Aquatic plants will take the ammonia first and leave the nitrate until last. Ammonia rapidly recycles, being taken up by the plants, passed on to the animals and bacteria, and excret- ed as ammonia again into the water. Nitrogen coming in from the ocean is mainly nitrate. There is a big reser- voir of nitrate in the ocean, and when deep water washes up onto the continen- tal shelf in one way or another, it brings some nitrate into the coastal zone. So there is an input of nitrate from the ocean, and this, of course, will be utilized by plants, will go into the cycle, and will be recycled as ammonia. There is a tendency to view micro organisms in two categories: the good guys who are nitrogen fixers and the bad guys who are the denitrifiers. We should remember that in reality what is impor- tant is that the cycle keeps turning over. If we did not have the denitrifi- ers, the nitrogen would become locked up somewhere, and not be in the atmosphere. The atmosphere could be depleted, not overnight, but in a rather short extent of geological time. Carbon is rarely a limiting ele- ment, as far as I am aware, in the coastal zone. There is approximately a thousand times as much of it in the wa- ter as the plants could utilize. There is a good supply of it in the atmosphere for the intertidal grasses and man- groves. We look upon the cycle of car- bon as something important to study, but not as something that is limiting the system in any way. The cycle of sulfur in the coastal zone may be more significant than we have realized. Sulfate is abundant in the ocean and is not going to be a lim- iting element. We are now interested in the sulfur cycle because there are vola- tile sulfur compounds being produced by organisms in the coastal zone. h^S and volatile organic compounds are going into the atmosphere. Such things as di- methyl sulfide and a number of other low molecular weight sulfur compounds are apparently produced by algae in substan- tial quantities (Lovelock et al . 1972). These are being produced, not just in anerobic sediments, but also by kelp beds or even phytoplankton, and con- tribute to the sulfur supply in the atmosphere. There is an input to the 145 atmosphere that is probably proportional to productivity, which means that the highly productive coastal zones are probably regions of relatively high input of sulfur to the atmosphere. Another high input of sulfur to the at- mosphere is from the burning of fossil fuels which contain sulfur. We associ- ate acid rain with the burning of fossil fuel, which is probably correct, but at the present time there is a certain amount of controversy as to the relative magnitude of sulfur production by the volatilization of sulfur from natural and anthropogenic sources. This is of practical importance because of the role of sulfur in acid rain. There are two ways in which we look upon elements like nitrogen and phospho- rus as key elements in aquatic coastal systems. One is as limiting factors, and the other is as causes of eutrophi- cation. Let us look first at the limit- ing factor aspect. In 1925, W. R. G. Atkins (1925) noted that the ratio of nitrogen to phosphorus in the English Channel was 16 atoms of nitrogen to 1 atom of phosphorus. This was true of both the material in solution in the water and the material bound in plank- ton. He noticed that in summer the nitrogen and phosphorus were depleted from the water and were tied up in the plankton at exactly the same time. Red- field (1934) extended the observation to the North Atlantic, and showed that the ratio of 16 to 1, nitrogen to phospho- rus, was true for surface ocean water in general in the North Atlantic. This has become known as Redfi eld's ratio because he extended it and pro- posed its cause. By recycling these ele- ments so rapidly, the phytoplankton come to control the ratio in the whole sys- tem. Redfield's ratio has come to be a kind of magic thing for ecologists, and we look for it wherever we go. We seldom find it except in the open ocean. In the coastal waters, one may find ratios as low as 3 to 1, or 1 to 1, much less nitrogen in proportion to phosphorus. This has led many people to say that nitrogen is the limiting element in the coastal zone, which may be true. However, the absolute amount of nitrogen in the coastal zone is far greater than in ocean surface water, so the limitation of production, if any, is a relative one. In the ocean there is relatively little nitrogen fixation or denitrification. In the coastal zone both processes are active, and the N:P ratio is controlled by the relative rates of those two processes. Our other concern is eutrophica- tion. The salt marsh in Georgia is a eutrophic system. It is a natural eutro- phic system, about as eutrophic as it could be without going out of balance. So eutrophication is not necessarily something that man does to systems. We can find systems which are naturally very productive and which an ecologist would call eutrophic systems. On the other hand, there are systems which are not naturally eutrophic which man can influence by organic pollution from human sewage waste or from industrial organic waste. When we make them eutro- phic, this usually leads to a condition which is not aesthetically pleasing to us. Eutrophication may have other problems associated with it. It cer- tainly will change the system. We can point to certain examples of this; New York Harbor and Houston Ship Channel are in competition for the worst system in the country, if not in the world (Smith 1972). Both are complicat- ed cases because there are various types of pollutants present, not just organic matter and nutrients, but toxins and organic compounds of all kinds. Eutro- phication is certainly part of the problem in both systems, and probably both are less eutrophic than they would be if they were not toxic. The old saying of the engineer is that the solution to pollution is dilu- tion. We have been applying this to the rivers and lakes of our continent and we have nearly reached the end of that. We have been applying it to the estuaries and we have nearly reached the end of that, too. Now we are looking at the ocean as the ultimate sink for our ex- cess waste. Right now, this is the cheapest thing to do. I suppose in the long run we could find ways to use wastes more effectively, to economically recycle them effectively rather than throw them away. In the long run the best thing to do is not throw away ni- trogen and phosphorus, and then find new sources for agriculture. In the short run, we have to throw them away 146 for economic expediency and look to the ocean as a sink. When we look to the ocean, we look first to the coastal zone. When an ecologist or an oceanog- rapher thinks of the ocean, he thinks of very deep water, usually far from land. However, most ocean dumping is virtually done on the beach. The real cost of dumping in the deep ocean is high, perhaps prohibitive in some in- stances, so we still have the problem of eutrophicating the coastal zone. When this kind of question comes up, one needs to ask where in the ocean is one going to dump waste. The coastal zone is much more resilient than the estuary, if one considers the coastal zone all the way out to the edge of the shelf. It is a large area, and it can take a lot of abuse. Therefore, we have to look at both sides of these questions. There are going to be many impacts on the coastal zone, taken in a broad sense, that are going to be quite rea- sonable and which the zone can assimi- late successfully. There are others that it can not. Nutrients are simply one of many aspects we need to consider in evaluating the increasing impacts on the coastal zone. LITERATURE CITED Atkins, W.R.G. 1925. The phosphate con- tent of fresh and salt waters in its relationship to the growth of algal plankton. J. Mar. Biol .Assoc. U.K. 13:119-150. Dugdale, R.C, and J.J. Goering. 1967. Uptake of new and regenerated forms of nitrogen in primary productiv- ity. Limnol. Oceanogr. 12:685-695. Haines, E.B. 1975. Nutrient inputs to the coastal zone: the Georgia and South Carolina shelf. Pages 303- 324 j_n L. E. Cronin, ed. Estuarine research, Vol. 1. Academic Press. New York. Johannes, R.E., J. Alberts, C. D'Elia, R. A. Kinzie, et al. 1972. The metabolism of some coral reef com- munities: a team study of nutrient and energy flux at Eniwetok. Bio Science 22:541-543. Lovelock, J. E., R. J. Meggs, and R. A. Rasmussen. 1972. Atmospheric di- methyl sulphide and the natural sulphur cycle. Nature 237: 452-453. Mann, K.H. 1972. Macrophyte production and detritus food chains in coastal waters. Mem. Inst. Ital. Idrobiol. 29(suppl.): 353-383. Odum, H.T., and E.P. Odum. 1955. Trophic structure and productivity of a windward coral reef community on Eniwetok Atoll. Ecol. Monogr. 25: 291-320. Pomeroy, L. R. 1970. The strategy of mineral cycling. Ann. Rev. Ecol. Syst. 1:171-190. Pomeroy, L. R., L. R. Shenton, R. D. H. Jones, and R.J. Reimold. 1972. Nutrient flux in estuaries. Pages 274-291 In G.E. Likens, ed. Nutri- ents and eutrophication. Am. Soc. Limnol. Oceanogr. Special Symposia Vol. 1. Pomeroy, L. R., E. E. Smith, and C. M. Grant. 1965. The exchange of phosphate between estuarine water and sediment. Limnol. Oceanogr. 10:167-172. Redfield, A.C. 1934. On the propor- tions of organic derivatives in sea water and their relation to the composition of plankton. Pages 176-192 vn James Johnstone Memorial Volume. Liverpool University Press, Liverpool, England. Reimold, R.J. 1972. The movement of phosphorus through the salt marsh cordgrass, Spartina alterniflora Loisel. Limnol. Oceanogr. 17: 606- 611. Rigler, F. H. 1956. A tracer study of the phosphorus cycle in lake water. Ecology 37:550-562. Riley, G. A. 1967. Mathematical model of nutrient conditions in coastal waters. Bull. Bingham Oceanogr. Coll. 19:72-80. Sargent, M.C., and T.S. Austin. 1949. Organic productivity of an atoll. Trans. Am. Geophys. Union 30:245- 249. Smith, J. N. 1972. The decline of Gal- veston Bay. The Conservation Foun- dation, Washington, D.C. 127 pp. 147 SALT MARSH CREATION: IMPACT OF SEWAGE Evelyn Haines University of Georgia Marine Institute Sapelo Island, Georgia 31327 Under the auspices of a project funded by the Office of Water Research and Technology entitled The. Capacity of the Spartina Salt Marsh to Assimilate Nitrogen from Sewage Sludge, two gradu- ate students, Barry Sherr and Alice Chalmers, and I have been studying the nitrogen cycle in coastal marine ecosys- tems. Our focus has been on the basic nitrogen cycle in the marsh as well as the impact of applying sewage sludge on- to the marsh; specifically, what happens to the nitrogen in the sludge? I will compare our study to a similar, although longer and more comprehensive, study which has been carried out by Valiela et al. (1974) in a Massachusetts salt marsh. Increasing amounts of sewage are being deposited in coastal wetlands be- cause this is an inexpensive and conve- nient way for urban areas on the coast to dispose of sewage. Unfortunately, a lot of the sewage has not even had pri- mary treatment, and the increasing bio- logical oxygen demand (BOD) in coastal wetlands has already resulted in marked deterioration of water quality in some northern estuaries. We cannot treat estuaries like giant flush toilets be- cause they do not flush. Estuaries are naturally productive because physical processes in the estuaries, e.g., sedi- mentation in the marshes and estuarine water circulation, tend to keep mate- rials that come into estuaries within the estuary. Thus, when sewage is intro- duced into an estuary, the materials tend to remain there. One of the major components of sew- age that we should be concerned about are the plant nutrients, e.g., in sec- ondarily treated sewage there will be phosphate, ammonia, and nitrate in large quantities which will stimulate phyto- plankton growth in the estuary, and vascular plant and benthic algal produc- tion in the marshes. Impacts from other sewage materials may be a bit more subtle. Heavy metals and chemicals, such as pesticides and petroleum hydro- carbons, are abundant in sewage. Also, very little is known about the fate of the pathogenic microorganisms in sewage in estuaries. Sewage impact on salt marshes can be experimentally evaluated by analyz- ing: (1) accumulation of substances such as inorganic nitrates, heavy metals, and pesticides in plants, fauna, and soils; (2) the stimulation of certain biologi- cal processes in the marsh, e.g., plant production and microbial activity; and (3) the inhibition of microbial process- es. There are also subtle, indirect ef- fects that cannot be predicted. By ob- serving a whole range of processes in the marsh, one may detect indirect chain reaction effects resulting from the im- pact of sewage on salt marshes. Gosselink et al. (1974) assigned a high monetary value to the ability of salt marshes to act as tertiary sewage treatment systems. Salt marshes are not very effective for secondary sewage treatment because salt marshes and estu- aries are such highly productive systems to begin with, and already contain plen- ty of organic material. If more organic matter in primary or untreated sewage is added, the estuaries will be overloaded, and the water will show decreased oxygen tensions and other signs of deteriora- tion. However, estuaries may be effi- cient at tertiary treatment for removal of inorganic nutrients in secondarily treated sewage. Pomeroy et al. (1972) reported the ability of marsh clay sedi- ments to extract phosphorus from water via chemical reaction. Apparently nitro- gen is the nutrient which is more inter- esting to study because addition of ni- trogen can increase plant productivity in salt marshes. Gosselink et al. (1974) assigned a per year value of $34,580 per ha ($14,000 per acre) to 148 northern estuaries presently "treating" secondarily treated sewage discharged into estuarine waters. Major differences between our study and that of Valiela et al. in Massachu- setts were (1) their study of the re- sponse of a salt marsh to sewage enrich- ment was carried out over several years, had controls of inorganic nutrient fer- tilization as well as nonfertilization and measured more marsh processes and (2) they used commercially prepared sew- age fertilizer which had been amended with inorganic fertilizer. We used sew- age sludge from an Athens, Georgia, treatment plant, air dried the sludge, and then ran it through a grinder to make it into a crumbly powder. Our sew- age sludge was from an anaerobic diges- tion process, but at times a significant fraction may have been only primarily treated. We applied the dry sludge at the rate of 25 g/m2 per week at biweekly intervals, which was equivalent to Teal and Valiela's high rate of fertiliza- tion. They also tested a lower rate of about 8 g/m2 per week. During our 1-yr study, a total of 1.2 kg/m2 was applied. We compared our fertilized short Spar- tina marsh with a tall Spartina creek- bank marsh and with a separate unfertil- ized short Spartina marsh as a control. In the first year the Massachusetts group did not report any increase in plant biomass (Valiela et al. 1975). After comparing their high frequency of sewage sludge fertilization with fertil- ization with urea only, they concluded that it was the nitrogen in sewage sludge that resulted in increased plant growth. Phosphorus fertilizer did not increase the standing plant biomass in either the low or high marsh. The sewage sludge and urea-enriched plots, which had the same nitrogen content applied, showed two- to three-fold increases in plant biomass (Valiela et al. 1975). Plants in a Massachusetts high marsh tended also to become morphologically more like plants in the low marsh during the sewage enrichment study. In the first year of sludge fertil- ization of our experimental plots, the aboveground live Spartina biomass in- creased about a third over our control Spartina biomass (Figure 1). In some months of the year our experimental plots had almost as much live Spartina biomass as the tall plants by the creek, which was the more productive area of the marsh. On the other hand, the dead Spartina biomass in our fertilized plots did not increase significantly above the control during the course of the experi- ment. One might expect that as the ex- perimental live plant biomass died off in the winter, there would be a corres- ponding increase in the dead material, but so far this effect has not become apparent. We also attempted to monitor the response of belowground plant biomass to enrichment. Measuring live belowground plant biomass was difficult in these marshes because: (1) there was so much dead matter and (2) the clay sediments clung to the roots so tightly that it was very difficult to accurately sepa- rate the live plant roots and rhizomes from dead roots and rhizomes. As a crude indication of belowground plant growth, we measured the total macro- organic matter (MOM), i.e., the organic material larger than 2 mm (0.08 inch) in our three plot areas. A seasonal comparison of the total belowground MOM to a depth of 30 cm in our three plots showed much variation (Figure 2). The trend during the course of the experiment was a slight increase in the belowground MOM in our experi- mentally enriched plots compared to the control plots. A rather drastic. drop in the amount of MOM in the tall Spartina (creekbank) marsh sites was also noted. The data also indicate that organic mat- ter is mineralized more rapidly in the low marsh sediments, which could explain in part the rapid disappearance of the creekbank soil MOM. Valiela et al. (1976) separated the live roots and rhizomes from the total dead belowground MOM by visual observa- tion and staining procedures. They found very little live root and rhizome material in comparison to the total amount of dead matter. The dry weight of live roots in their Spartina marsh was much less than the dry weight of the rhizomes. Sewage fertilization appeared to decrease the standing crop of roots in the marsh. Valiela et al. (1976) speculated that the enriched plants re- quired fewer roots because they had a relatively higher standing stock of 149 1,500 1,000 - 1975 1976 Figure 1. Seasonal variation of live above ground biomass in the study plots, mean ± 1 SE 3,000 - 2,000 1,000 ■ Chalmers et al. 1976). □ Low Marsh O High Marsh # Experimental High Marsh 1— Jan. 1975 Mar. — I — May — i — June Sept. — i — Nov. — I Jan. 1976 — I — Mar. Figure 2. Seasonal variation of below ground macro-organic matter as grams ash-free dry weight (AFDW) per m2 for the study plots (Chalmers et al. 1976). 150 nutrients than did control plants. In plots given the high level of sewage fertilization, the amount of roots was less than in the lower fertilization level plots or in the control plots. In plots fertilized with urea, the root mass was about the same as that of control roots. In the high marsh, there were also fewer live roots in the high enrichment level than in the control. However, the amount of rhizomes and the amount of dead matter differed very lit- tle between the fertilized and unfertil- ized plots. Sewage fertilization appar- ently does not stimulate belowground growth, and may, in fact, decrease root growth in salt marshes. Valiela et al. (1976) found a seasonal root production pattern with an increase of root growth in the spring, followed by a decline in live root biomass. Sewage enrichment can effect pro- cesses in the marsh other than plant growth. Addition of sewage fertilizer to a Massachusetts salt marsh decreased rates of nitrogen fixation in the marsh after the amount of ammonia in the sedi- ment interstitial water increased (Van Raalte et al. 1974). An increase in denitrification was observed in the en- riched plots that was significantly higher than that of the unfertilized plots (Valiela et al, in press). The authors did not quantify this to deter- mine exactly how much of the added ni- trogen was lost through reduction to gas. Consequently, they surmised that the marsh could effectively remove the nitrogen in sewage. Sewage nitrogen de- pressed the natural rate of nitrogen fixation, and the marshes used nitrogen in the sewage rather than nitrogen that would have been available through nitro- gen fixation. At the same time, in- creased rates of denitrification in the marsh could remove more of the nitrogen in the sewage. The rate of benthic algal produc- tion,which might be expected to be stim- ulated, actually decreased in Massachu- setts (Estrada et al. 1974; Van Raalte et al. 1976). This decrease is a good example of an indirect effect of sewage enrichment. The rate of benthic algal production decreased in the fertilized plots because the increased standing plant biomass shaded the algae to the extent that the algae were light-limit- ed. In our marsh, Bob Christian and Keith Bancroft studied the effect of sludge fertilization on microbial popu- lations and activity. They measured adenosine tri -phosphate (ATP) in the sediment and found no differences in ATP (as a measure of microbial biomass) in the experimental plots compared to the control plots. Bancroft also analyzed the "energy charge" of the macrobial population as a measure of microbial activity, i.e., whether they are simply resting spores with a low energy charge or cells growing exponentially with a high energy charge. No difference in the energy charges was found between the sludge fertilized plots and the control. Apparently, the microbial populations in a mature marsh soil are very resistant to change in their immediate enrichment. Valiela et al. (in press) presented a summary of the natural budgets of three different heavy metals (lead, zinc, and cadmium) in a marsh and com- pared the same budgets with a forcing function of the added metals in a sludge fertilizer applied to a marsh. About 90% of the added lead was retained in the marsh sediments, a small amount was lost, and some was accumulated in the marsh plants. More of the zinc (16.7%) was lost from the marsh, and Valiela et al. (in press) theorized that the zinc was exported from the marsh on sediment particles or as dissolved inor- ganic compounds. The remainder of the added zinc was accumulated in marsh sed- iments and plants. About half of the cadmium was lost by unknown mechanisms, and half was accumulated in sediments and marsh plants. Is salt marsh disposal a good way to get rid of sewage? I agree with Pomeroy et al. (1969) that we should probably regard sewage as a resource rather than as a waste product. If we need to get rid of sewage, in some re- spects the salt marsh is a good tertiary treatment facility. Marsh plants and benthic algae have high rates of produc- tion and can assimilate some nutrients. The clay soils in Georgia estuaries can accumulate a lot of phosphate. The marsh is a fairly stable community and appears to be quite resilient, at least to enrichment stresses. The accreting 151 sediments in salt marshes can allow for long-term storage of materials in the soils. Of course, the extent to which one can get rid of sewage in this fash- ion will depend on how much sedimenta- tion is taking place. In the Massachusetts marsh, the ac- cretion rate was a matter of centimeters per year, and in the Georgia marsh, the sedimentation rate is considerably less, about a millimeter per year. In Mass- achusetts, about 80% to 96% of the ni- trogen added in the sewage sludge fer- tilizer was retained in the marsh sedi- ment, whereas in our study we can only account for 60% of the nitrogen that we added in sewage sludge; the rest was probably washed out by the tides. Some of the nitrogen could have been denitri- fied or volatilized as ammonia off the sediment surface. The Massachusetts group found that the waterlogged sedi- ments in the marsh soils apparently can get rid of significant amounts of nitro- gen through denitrification. On the other hand, the accumulation of toxic materials in marsh sediments will have long-term effects which we do not know much about. The marsh plants can pump certain ions, which might include toxic compounds, from the soil to the estua- rine water. We also do not have any idea about the maximum loading rate be- yond which the marsh system will begin to deteriorate. BIBLIOGRAPHY Banus, M.D., I. Valiela, and J.M. Teal. 1975. Lead, zinc, and cadmium bud- gets in experimentally enriched salt marsh ecosystems. Estuarine Coastal Mar. Sci. 3:421-430. Chalmers, A.G., E.B. Haines, and B.F. Sherr. 1976. Capacity of a Spar- tina salt marsh to assimilate ni- trogen from secondarily treated sewage. Environ. Resour. Cent. Ga. Inst. Technology. Atlanta. Tech. Rep. ERC-0776. 88 pp. Christian, R.R. 1976. Regulation of a salt marsh soil microbial communi- ty: a field experimental approach. Ph.D. Dissertation, Univ. Georgia, Athens. Estrada, M. , I. Valiela, and J.M. Teal. 1974. Concentration and distribu- tion of chlorophyll in fertilized plots in a Massachusetts salt marsh. Louisiana State Univ., Center for Wetland Resources, Baton Rouge. LSU-SG-74-03. 30 pp. Gosselink, J.G., E.P. Odum, and R.M. Pope. 1974. The values of the tidal marsh. Center for Wetland Resources, Louisiana State Univ., Baton Rouge. Sea Grant Publ. LSU-SG-74-03. 30 pp. Krebs, C.T., I. Valiela, G. Harvey, and J.M. Teal. 1974. Reduction of field populations of fiddler crabs by uptake of chlorinated hydrocar- bons. Mar. Pollut. Bull. 5:140-142. Marshall, D.E. 1970. Characteristics of Spartina marsh receiving treated municipal sewage wastes. M.S. The- sis. Univ. North Carolina. Pomeroy, L.R., R.E. Johannes, E.P. Odum, and B. Roffman. 1969. The phos- phorus and zinc cycles and produc- tivity of a salt marsh. Pages 412-419 j_n D.J. Nelson and F.C. Evans, Proceedings 2nd national symposium radioecology. U.S.A.E.C. Conference 670503. Pomeroy, L.R., L.R. Shenton, R.D.H. Jones, and R.J. Reimold. 1972. Nutrient flux in estuaries. Pages 274-291 in G.E. Likens, ed. Nu- trients and eutrophication: the limiting-nutrient controversy. Am. Soc. Limnol. Oceanogr. Special Symposia. Vol. 1. Valiela, I., and J.M. Teal. 1974. Nu- trient limitation in salt marsh vegetation. Pages 547-563 j_n R.J. Reimold and W.H. Queen, eds. Eco- logy of halophytes. Academic Press, New York. Valiela, I., M.D. Banus, and J.M. Teal. 1974. Response of salt marsh bi- valves to enrichment with metal- containing sewage sludge and reten- tion of lead, zinc and cadmium by marsh sediments. Environ. Pollut. 7:149-157. Valiela, I., J.M. Teal, and N.Y. Persson. 1976. Production and dynamics of experimentally enriched salt marsh vegetation: below-ground biomass. Limnol. Oceanogr. 21:245-252. Valiela, I., J. M. Teal, and W. Sass. 1973. Nutrient retention in salt marsh plots experimentally fertil- ized with sewage sludge. Estuarine Coastal Mar. Sci. 1:269-271. 152 Valiela, I., J. M. Teal, and W. Sass. Van Raalte, C, I. Valiela, E.J. Carpen- 1975. Production and dynamics of ter, and J.M. Teal. 1974. Nitro- salt marsh vegetation and the ef- gen fixation: presence in salt feet of experimental treatment with marshes and inhibition by additions sewage sludge. I. Biomass produc- of combined nitrogen. Estuarine tion and species composition. J. Coastal Mar. Sci. 2:301-305. Applied Ecol. 12(3) :973-981. Van Raalte, C. D., I. Valiela, and J. M. Valiela, I., S. Vince, and J. M. Teal. Teal. 1976. Productivity of benthic In press. Assimilation of sewage algae in experimentally fertilized by wetlands. Estuarine Research, salt marsh plots. Limnol. Oceanogr. Vol. 3. In press. 153 THE PRICING AND EVALUATION OF NATURAL RESOURCES Ronald M. North Director Institute of Natural Resources University of Georgia Athens, Georgia 30602 As an economist, I believe we have been working with complex interrelation- ships very successfully as a profession for 200 yr. Civilized nations created monetary systems wery early as a common denominator for value either as a stock or a transaction. I do not propose to bring you the answers, but I will dis- cuss how economists think and some of the strange things they do or say. We define economics as a study of any action or process which has to do with the creation of goods and services to satisfy human wants. As I look over this program, I see it is concerned with creating salt marshes, sand dunes, man- grove swamps, and habitats associated with these areas. In effect, there is concern with creating goods and ser- vices. This program does suggest an economic interest; therefore, the plan of action this evening will be to dis- cuss some of the economic interests in natural resources and how we as econo- mists try to work with natural scien- tists in understanding the biological and social interface. I will also try to explain some of the basic premises of economics and spend just a few minutes with the economic thought processes. Then I would like to open the meeting to any questions you have. I was impressed by some of the problems ecologists do face and the fact that perhaps we econo- mists have not adequately addressed those problems yet. There has been interest these past few days in the technical creation of communities in salt marshes and other coastal habitats. I am certain the con- cern has had to do with the state of the art for increasing the quantity or the quality, or both, of these coastal habi- tats. For example, I am sure some of the questions asked include how do we create more salt marshes, or more sand dunes, or how do we manage such areas to create a viable and a productive habi- tat? I am sure questions have arisen as to how much do these habitats cost and how much do they produce? But has it been asked to what extent do they satis- fy human wants? Keeping these thoughts in mind may help explain some of the thought processes of economists and some of the problems we have. Remember, eco- nomics is often defined as not just the creation of goods and services, but also the creation of those goods and services that satisfy human wants. Proceeding further with the defini- tion, one could say that economists are a bunch of narrow-minded, selfish fel- lows who are only interested in humans and the personal satisfaction of the species. Perhaps that is correct. Per- haps most economists are introverts, but we are really interested in economics as a body of knowledge wherein the central interest is, and should be, the satis- faction of human wants. I ask you also, would not Darwinian survival theory sup- port this economic premise of satisfying human wants by the production of goods and services? Since this is the Bicentennial, I will mention that Adam Smith's book "In- quiry into the Theory and Wealth of Na- tions" was first published in 1776, 200 yr ago. I will not go into much detail, except to say that Adam Smith's concept of the economic man has a direct ecolog- ical counterpart. The concept is that economic man is one who goes about pro- ducing goods and services for himself and in so doing contributes to the wel- fare of society as a whole. The economic man is led by an invisible hand to pro- mote an end which is no part of his in- tention. A layman could easily conclude from the literature of ecology that each ele- ment of the food chain goes about pursu- ing its own interests in making a living 154 while quite unintentionally providing a meal for the next link or a service to some link far removed. If one thinks a little about Adam Smith's concept of economic man or an ecologist's concept of an ecosystem, one can easily conclude that both concepts are quite self-cen- tered and perhaps immoral with respect to religious or philosophic concepts of life. However, we do recognize those religious or philosophic concepts which arise in humans, by their will, to pro- duce goods and services to serve their fellow man, not just for themselves. Some economists avoid this moral issue by assuming that economists do not make moral judgments, that it is not the do- main of economists to make moral judg- ments. The economist concludes that he is only interested in the efficiency with which man goes about producing his goods and services. I suppose there is no single con- cept in economics that gets us into more trouble that this concept of efficiency and what it means. However, this assump- tion, that the central objective of eco- nomics is efficiency, has led to the development of two factions or two ap- proaches in both the economic literature and in professional practice. These are the positive and normative approaches to economic thinking. The basis of the positive approach is to avoid moral, ethical, or normative judgments and to take the economic sys- tem as it is. We take the economic sys- tem as it is to be studied, modeled, forecasted, and reacted to; we accept the economic system for what it is. This is the modern version of the Adam Smith's classical school, in which self- interest is the prime motivation for all economic behavior. Positive economists generally conclude that both individuals and the whole society benefit most with- out governmental intervention in eco- nomic life. The basic premises are indi- vidual economic freedom and private property. The basis of the normative approach is to make value judgments respecting the performance of the economic system. The normative economist is not satisfied with what is, but espouses a belief that economists should be concerned with what should be. This line of thought, which developed from the mid-19th century his- torical school, largely in Germany, says that economic policy should be derived from lessons in history and should evolve to meet judgments about human needs. The normative economist consid- ers the government to be the most re- sponsible motivator for economic behav- ior. The basic premise is government direction of economic activity and ex- pansion of what we call the public in- terest doctrine, that is, the doctrine of an expanded public role of govern- ment, particularly with respect to natu- ral resources which would become a pub- lic trust for the use of all people. Now that we have established the rationale for all things coming in pairs, such as normative and positive economics, male and female, and Demo- crats and Republicans, perhaps we can better understand why economists never seem to agree and why so many economic statements seem pardoxical or certainly contradictory with respect to their pur- pose. I would like to explore some of the more substantive economic concepts which relate to pricing natural re- sources generally and to coastal ecosys- tems particularly. First, the major subject matters with which we are concerned include pro- duction, consumption, distribution, and allocation. These terms refer to tech- nical aspects of economics. They are technical in the sense that production includes the physical and economic com- binations of goods and services consump- tion refers to the limits and choices in consuming certain resources or goods and services; distribution is the process of equalizing supplies and demands among producers and consumers; and allocation is the scheme by which we permit re- sources or goods and services to be own- ed or controlled by the various sectors of the economy. The economic theory counterparts of these technical aspects include, for production — the familiar supply func- tions; for consumption—the demand func- tions; for distribution — the exchange system; and for allocation — the pricing system. Of course, pricing and exchange get mixed up quite a bit. Pricing is a part of any exchange, but in a modern economic system pricing is much more; 155 it is directed toward achieving an equi- librium. The economic concept of supply and demand requires a price. Without a price one has no supply and demand func- tions—merely physical production and consumption. the economic concept of supply and demand must include a price. The simplest exchange system in the world is a barter system where there is no cost of exchange. However, in a com- plex society where the producers are far removed from the consumers, one has large costs of exchange. I think this is one of the larger problems we face in the economy today. People are disgrun- tled with the high cost of exchange, the high cost of moving a tomato from south Florida to New York City. People cannot readily understand costs of exchange. Many people would very much like to see if we could not do things a little dif- ferently in the exchange system. That is, could we go back to a simpler econ- omy in which the costs of exchange could be reduced? I do not see much hope for reduced exchange costs. Most of us would not accept a primitive economy. We like luxuries too much to revert to spending so much time producing directly what we consume. The exchange system governs the allocation of resources. The positive economist accepts the premise that the existing allocation of resources and goods and services is acceptable. We allocate goods and re- sources in the relatively competitive economy through the ownership or control of those resources. The economist looks at four basic groups or categories of resources which are familiar to all: land, labor, capital, and management. In land, we include all of the natural resources, the renewable resources, such as wildlife, and nonrenewable resources such as extractive minerals. These nat- ural resources are embodied in the econ- omist's concept of land. The ownership of land and the resulting allocations are accepted by the positive economist as a fait accompli including the rents that are paid for land. The rent is the price for the use of that land. The rents that accrue to land are the method of allocating a part of the total goods and services of the economy to the own- ers of land. The same is true of labor. Most of us sell our labor, which includes the technical skills we have. In fact, most of us in today's society have little to sell except labor. As we sell our la- bor, goods and services in the economy are allocated to us on the basis of our ability to command a price for our la- bor, a wage if one will. Of course the owners of capital, essentially investors, receive the in- terest, and management receives the residual or profits, or various other forms of compensation which might result from the ownership of the particular technical skills required to combine the land, labor, and capital into a produc- tive operation. The heart of all this production, consumption, distribution, and alloca- tion is a price system. What I would like to point out is that there are other ways of allocating besides a price system. We can allocate by law; we can legislate. We do a lot of that. We de- velop a policy or a standard or we pass a law. For example, the national efflu- ent discharge permit system is a policy which affects allocation of resources. In this case, resources are reallocated from the private users of products to the public sector. Costs of effluent disposal are subsequently passed on to the consumers rather than being absorbed by the reduction in fishery habitat. The ultimate legislated allocation of goods and services would be in a cen- tralized economy, wherein one just pass- es down a budget or sets an arbitrary price or allocates goods and services on whatever premises may be arbitrarily judged appropriate. The two polar posi- tions are the laissez-faire of a free market allocation system y_s_. the cen- tralized government allocation system. These are the two extremes of allocation systems, both of which must have a pric- ing system for balancing needs and sur- pluses, demands and supplies. The pric- ing system is often referred to errone- ously as being inaccurate or inappropri- ate. The pricing system is not perfect. I will try to explain some of the limi- tations of pricing systems so that we can understand how to better use prices as a guide to resource allocations. The problems in the pricing system are most noticeable in areas of natural resources and environmental concerns where markets are not well-defined. We 156 can do lot of tinkering with the pricing system to improve resource allocations. But we must not conclude, as do some economists and many noneconomists, that we should throw out the pricing system because it does not work perfectly. My conclusions are that the pricing system is the best thing we have going for us in terms of allocating goods and ser- vices. What we need to do is to identify long-range concerns with respect to overall goals and select those areas where market prices seem incompatible with social needs to do some tinkering with the pricing system. For economic efficiency we must maintain a reasonably effective system of market pricing. There are several theories with respect to what a market price is. In a competitive economy a market price is one which no individual, no firm, no government agency can affect by itself through its buying or selling. In other words, it is all of the deci- sions made in the economic system as a whole which determine the market price. We do have a few situations of op- erating competitive market price systems that work fairly well. The wheat market is about the best example of a competi- tive market system one can find since there is no buyer nor any individual farmer, by himself, that can affect the price of that commodity. However, as we move into more restrictive market struc- tures, we start tinkering with this com- petitive market price. Some of the tink- ering we do deliberately to effect pub- lic policies, or to effect preferences, or to accomplish goals other than the allocation of goods and resources. In the economics profession, the model we use is the perfectly competitive econ- omy. That is the model on which our theoretical base rests. The opposite of the competitive model is the monopoly or the single firm situation in which the firm, the indi- vidual, or the government by its own de- cision controls the price for a commod- ity by controlling the amount that is offered for sale. In this monopolistic situation, the prices are generally above both the average cost and the mar- ginal cost of production. Therefore, we have a disequilibrium when measured against the competitive model. A dis- equilibrium exists since the monopolist, in controlling the amount of output and affecting the price, can obtain excess profits from the enterprise. There are certain industries with such unique characteristics that they are natural monopolies. That is, it would be uneconomic or inefficient to allow, for example, public utilities to compete with each other in the open mar- ket. We would have power lines all over the place. These industries are desig- nated as natural monopolies which we control by government intervention by regulating their economic activities. This is one of the first areas where we have government intervention or tinker- ing with the price system. The govern- ment issues an exclusive franchise to serve a certain segment of the popula- tion or State or municipality. In ex- change for that franchise without compe- tition, the government regulates the prices charged. This creates an inflexibility or a rigidity in which adjustments are not easily made for changing conditions. Any needed changes are costly, ineffi- cient, and vigorously opposed by incum- bents. If one does not believe this, one can read some of the newspapers about problems of the Administration's efforts to deregulate the airline and trucking industries which have been pro- tected from competition. A power utility with a franchised area is certainly not interested in deregulation. The indus- try enjoys regulation because it has a guaranteed return on investment, and that is something the wheat farmer in a competitive market does not have. Those are the two extremes. There are other ways in which we tinker with the price system, especially through what I refer to as administered prices. We live in a system of administered prices. The environment for administered pricing is one in which we have a few firms or a group of firms or an industry in which people can either get together or, perhaps, because of the structure of the industry, intuitively determine a pricing scheme which is higher than a competitive price. Let me illustrate how we tinker with prices to change the value of goods in a market to better understand the value system for marsh- lands and the pricing system from the perspective of the economist (Figure 1). 157 Market A 1. Sell total supply of 24 at market price of $16 to yield total revenue $384. PRICE Market B Differentiate market and sell 14 in market A at $27 to yield total revenue $378; also sell remaining 10 in market B at $22 to yield total revenue $220. The total market revenue $598. SUPPLY Figure 1. Price discrimination between two markets by product differentiation and market exchange control at no additional marketing cost. 153 If we have or can develop two mar- kets, A and B, which by definition have different demand functions and thus dif- ferent average revenue schedules in each market, we can easily see how a single firm or group that produces a single product can manipulate or administer these prices by allocating the product in different markets. The classic example is in dairying. The dairy industry has two sets of prices: one for fresh milk and one for manufactured milk. We also practice dis- crimination in the international market, where we have one set of export prices and another set of domestic prices. The criteria for administering prices is that we must separate the two markets to prevent arbitrage or prevent any unau- thorized exchange between the two mar- kets. If we have a single demand and a single quantity of product, say 24 blue tutus, we would sell all 24 in market A for Pm or $16 for a total revenue of $384 , a simple one-price market system for a supply of 24 tutus. If we discover that red tutus can be sold in another market at no addi- tional cost, we can allocate the total tutu supply, Qm, between markets A and B on the economic principle of equating the marginal revenues in the two markets at Qa and Qt, respectively, where the marginal revenues for blue tutus, MR and red tutus MR^ are equal. Now the prevailing market prices are Pa ($27) for blue tutus and Pb ($22) for red tutus. This differentiation of the tutu market into blues and reds now yields total revenue for 24 tutus of $598 ($378 for blue tutus and $220 for red tutus) - a significantly larger revenue by defin- ing the two markets than could be ob- tained in the single market. This is one way to manipulate prices. We do this every day and this is why, in adminis- tered pricing systems, we get pricing and allocation of resources which are less efficient in terms of the competi- tive model . We frequently manipulate prices for public utilities where the units of pro- duct consumed must be used sequentially. In this case, we start out with a series of declining block pricing schedules for electrical energy, a product in which the consumer must buy the first unit before he can have a second unit. Therefore, the firm or industry can con- trol the price charged for successive units. In this situation, the control- ler of the resource or product gains most of the value under the demand curve by block rate pricing. This is the pricing system that exists in most pub- lic utilities, such as communications, water systems, power systems, and others. These administered prices have little in common with a competitive pricing system, which is the standard against which we measure the economic performance of an industry or a firm. I hope this gives you some idea of how some economists earn their living and how prices, regardless of how they are determined, serve to allocate resources rather efficiently within whatever con- straints are imposed by private or gov- ernment manipulation. Let me briefly touch on another matter which affects prices and values, with respect to the three basic types of goods that we deal with and how the character of the goods affects price. There are economic goods, free goods, and public goods. An economic good is anything that has value in use or that is scarce, i.e., anything for which we are willing to pay. Anything with a price is an eco- nomic good. Free goods are those that are abundant, there is more than enough to go around, and therefore there is no price. You can always tell a free good because it has a zero price. We have this third category which really gives us problems. That is the public goods which society values, but has no effec- tive way of pricing to its individual members. Public goods fall into the area of things that we intuitively hold to be good or valuable, but which we are un- willing, as individuals, to pay for. It is the normative concept. Because of the nature of these goods or services which cannot be individually owned or controlled, we as individuals are not willing to pay for them. The result is a situation in which you have the free rider problem, where people can enjoy certain goods or services without having to pay. There is a terrific enforcement problem, such that beneficiaries of these economic activities cannot be 159 excluded for nonpayment. Such public goods include defense, schools, and var- ious governmental services in which we feel strongly that, even though there may be a limited private market, the common good would be better served by vigorous governmental participation. Of course, defense is the largest public good that we provide ourselves, and you can immediately see the exclusion prob- lem in these things. If one provides national defense, one can not exclude a citizen beneficiary. On a smaller scale, we have the same situation with respect to a flood- plain. That is why we have so much gov- ernmental activity in flood control and flood damage reduction. The assumption is that flood control is a public good because, within the floodplain itself, one cannot easily exclude anyone who is unwilling to pay for that protection. Of course, there are various police or leg- islative methods through which one could require payment, but one cannot get a voluntary payment. Much of the nation's natural re- sources fall into this category of pub- lic goods, or at lease in the transition from a free good to a public good. In the water resources area, we have been able to see the transition of water as a commodity from a free good (where there was little or no price attached to it), to a public good, and thence to an eco- nomic good in which the price is quite high. It is the public goods sector where we have our real problem with pricing. How do we price the public goods? How do we charge the beneficia- ries of public goods? Related also to the public goods sector is a concept which I often find advantageous to explain, that is, the concept of externalities. An externality exists when one cannot exclude a bene- ficiary from receiving a benefit, nor can one wery easily force him to pay for a benefit received. Normally, we have thought of externalities in terms of negatives or negative goods. For exam- ple, pollution is an externality because we have traditionally discharged our ef- fluents and our pollutants for zero pri- vate cost. Any cost incurred was either borne by third parties, such as down- stream people or downwind people or by the public sector in terms of wildlife damage or habitat damage. An externality exists when the market system cannot voluntarily and effectively register or sum the total merits of the good. We sometimes make people pay by passing a law or by enforcing a standard such that we internalize these costs. The only other recourse is through the courts. Recently, we have had a lot of settle- ments of externalities through the courts in both the private and public sectors, especially, since the National Environment Policy Act (NEPA) of 1969. The last thing I would like to men- tion is with respect to the goals and objectives of economics. The first is that of achieving efficiency. Efficiency is the objective with which we are most frequently concerned. The companion con- cept to efficiency, and one we do not hear too much about, is equity. The con- cept of equity does not necessarily mean equality. Equity in economics more ac- curately means fair treatment rather than equal treatment. Equity refers to the distribution or changes in the dis- tribution, which exist or may be brought about by economic or political activi- ties. In any public policy decision or in any economic decision, we always have the two impacts: the efficiency impact and the equity impact. The central ques- tion of efficiency is how much does it cost or how much does one pay for it? The central quesion of equity is who pays? Some policy decisions increase ef- ficiency; some certainly decrease effi- ciency. Most policy decisions change the distribution of benefits and costs so that some groups of people are enriched, or at least made better off, while others are damaged or made worse off. For ex- ample, if the Environmental Protection Agency should impose an effluent dis- charge standard on kraft mills but not on newsprint mills, then' this would dam- age users of kraft relative to users of newsprint. It would increase kraft costs and affect both producers and consumers of their products. This is a situation in which a policy decision has an ad- verse equity impact. However, the total efficiency for the economy may be either good or bad, depending on the tradeoffs between the predecision social costs and postdecision private costs. Efficiency is the size of the pie, and equity is 160 how we slice the pie for the various sectors. In the free market system we solve our equity problem by saying that the existing allocation of resources and talents and goods and services is ac- ceptable. This is the positive approach. In the normative approach we say that the equity situation is unacceptable; therefore, we will implement certain policies to change the distribution of goods and services, either as flows or as stocks. This approach results in progressive income taxes, progressive excise taxes, and transfers from one sector of the economy to another, gener- ally by governmental activity. The ob- jective is to change the equity status by changing the payees and beneficiaries for the given economic activity. Going further into the goals of economics, we have several that I should mention. One goal that is often attrib- uted to economics is that of growth. Growth is defined as an increase in the gross national product. Now this is a perennial national policy. We wish to grow at a certain rate, to increase the gross national product at a certain rate, to keep the growth from declining too much. It is the rate of growth that we are interested in. Another national goal is to have full employment. This is essentially the thought that everybody who wants a job should have the opportunity to have one. However, as you see in a complex industrialized society, we have great difficulty balancing full employment and economic growth. Another national goal is a stable price level, or control over inflation. These are the three basic national economic goals: growth, full employment, and stable prices. Of course, we have not determined how to achieve these three goals simultaneously. It seems we cannot have all of these things. We have to reach some kind of a compromise. When we get dif- ferent answers about what the national policy should be with respect to inter- est rates, with respect to the taxing system, or with respect to the welfare system, we are trying to reach some kind of agreement about what the national goals are with respect to balancing growth rates, employment, and price levels. All the other things to do with investments in our natural resources would be subject to these overall larger goals. For any goal or mix of national economic goals, how much are our natural or environmental resources worth? There are several ways we try to value natural resources where there is no established market. If we have a market in which prices are established, then we have a dollar measure of the value of those re- sources at any given time. There are five different methods of evaluation and each method will give one a different value for a nonmarket good. The first one is the market value to the consumer or the participant. This is a measure of the direct market value of the activity in terms of alternative costs of purchasing on the market a dif- ferent type of activity or a different good. That is, we are always trying to get the best deal for the dollar in the market. The market value is determined on the basis of our willingness to pay directly for a good, a service, or an activity. This is a direct method of measuring value in the commercial sec- tor. The second method is the sectoral economic impacts, which are the direct impacts of an investment or an expendi- ture in a community. The multiplier ef- fect that comes from an initial expendi- ture is alleged to measure the larger efficiency impact of a consumption or investment activity. If the expenditure is for a good or service, where it is retained largely in the designated area, one has a high multiplier of three, four, or five dollars of activity in a given geographic area. However, when the initial expenditure is for an import or where the material and labor are brought in from the outside, then the local multiplier effect is very low and there is little or no economic impact. This method of measuring value by the sectoral impact is often used as an estimate for a hunting day or a fishing day spent in a particular area. The direct expenditure, plus the multiplier impacts, is perceived as a measure of the real value of a resource in the pub- lic sector. The third measurement is the per- sonal cost of participation. This is a surrogate for total willingness to spend 161 » for all direct and associated costs of participation. In recreational activi- ties this would include the associated cost of travel, lodging, special equip- ment, and similar items. It is the cost of getting there or the total cost of participating which is perceived as the real value of a natural resource used in this manner. The fourth method of measurement is the social value to the participant. This is essentially a measure of how much each participant or each consumer values the activity or the goods or ser- vices he is purchasing, such as a fish- ing experience or a hunting experience. Perhaps more accurately, the way the economist measures this social value is the willingness to forgo the experience. In other words, instead of asking how much is one willing to pay, one would ask how much is one willing to give up to participate in this activity? Would one give up a whole day's wage or would one give up two days' wages for half a day of fishing? That would be the social value as we measure it. According to most of the research we have done, this method gives the highest value. The di- rect market value generally gives the lowest value. Another evaluation technique I wish to mention is what we call the reserva- tion value to potential participants. One will also see this referred to as "option demand." The reservation value is a measure of the willingness to re- serve or maintain an opportunity to par- ticipate or enjoy a good in the future. In other words, I am buying an option for future participation. I do this by paying dues to the Sierra Club to pre- serve an area or by making a contribu- tion to a museum for an art piece. The option demand is simply a normative judgment that I would like to have the opportunity for future participation in an activity. It is irrelevant whether or not I ever participate. This is the driving force behind the valuation of much of our natural resources, particu- larly all the parks, game refuges, and things we would like to preserve for the future. This reservation value is a rela- tively new approach that economists have taken. There is not much in the litera- ture on it yet, and we are just getting around to formalizing this concept of an option demand. If there is any approach that might be worthwhile researching in terms of natural resources, fisheries, wetlands and wildlife valuation, it is the concept of an option demand. At least, it is a positive approach which recognizes that these resources have values for the future. What we need is a way of formalizing the concept just as we have formalized market pricing and the various discriminatory pricing sys- tems mentioned earlier. In summary, I hope we have devel- oped a better understanding of the role of prices and the pricing system in al- locating and managing our natural re- sources or natural environments. At least we have looked at some of the ap- plications of pricing theory in both the private market sectors and the public goods sectors of the economy. We have also looked at the limitations of a pricing system as a basis for the eval- uation of either current values or in- vestment decisions that involve the man- agement and development of natural re- sources, such as estuaries, fisheries, and wildlife. Many people are proposing the existence of enormous prices (what they really mean is value) for natural environments in the hope of attracting attention to their management, develop- ment, or preservation. However, these proposals will not be taken seriously by society unless they can be adequately documented and verified either empiri- cally or intuitively. We face the pros- pect of living with a range of prices and values for our natural resources within which reasonable political deci- sions can be made for this segment of the public goods market. ••;■. 162 •U.S. GOVERNMENT PRINTING OFFICE: 1980—772-253/196 % ©-© LEGEND U*>— Headquarters - Office of Biological Th Services, Washington, D.C. _. National Coastal Ecosystems Team, Slidell. La. 6) Regional Offices Area Office U.S. FISH AND WILDLIFE SERVICE REGIONAL OFFICES REGION 1 Regional Director U.S. Fish and Wildlife Service Lloyd Five Hundred Building, Suite 1692 500 N.E. Multnomah Street Portland, Oregon 97232 REGION 4 Regional Director U.S. Fish and Wildlife Service Richard B. Russell Building 75 Spring Street, S.W. Atlanta, Georgia 30303 ALASKA AREA Regional Director U.S. Fish and Wildlife Service 1011 E.Tudor Road Anchorage, Alaska 99503 REGION 2 Regional Director U.S. Fish and Wildlife Service P.O.Box 1306 Albuquerque, New Mexico 87103 REGION 5 Regional Director U.S. Fish and Wildlife Service One Gateway Center Newton Corner, Massachusetts 02158 REGION 3 Regional Director U.S. Fish and Wildlife Service Federal Building, Fort Snelling Twin Cities, Minnesota 55111 REGION 6 Regional Director U.S. Fish and Wildlife Service P.O. Box 25486 Denver Federal Center Denver, Colorado 80225 4? DEPARTMENT OF THE INTERIOR U.S. FISH AND WILDLIFE SERVICE ■*, As the Nation's principal conservation agency, the Department of the Interior has respon- sibility for most of our nationally owned public lands and natural resources. This includes fostering the wisest use of our land and water resources, protecting our fish and wildlife, preserving the-environmental and cultural values of our national parks and historical places, and providing for the enjoyment of life through outdoor recreation. The Department as- sesses our energy and mineral resources and works to assure that their development is in the best interests of all our people. The Department also has a major responsibility for American Indian reservation communities and for people who live in island territories under U.S. administration.