MONTANA STATE LIBRARY 3 0864 0015 4585 7 BIOLOGICAL INTEGRITY OF COTTONWOOD CREEK, FERGUS COUNTY, MONTANA BASED ON THE COMPOSITION AND STRUCTURE OF THE BENTHIC ALGAE COMMUNITY • Prepared for: State of Montana Department of Environmental Quality P.O. Box 200901 Helena, Montana 59620-0901 Project Officer: Rebecca Ridenour DEQ Contract No. 200012-3 Prepared by: Loren L. Bahls, Ph.D. Hannaea 1032 Twelfth Avenue Helena, Montana 59601 November 1, 2001 ^rv-!,MrMTS COLLECTION ■■-' 2 8 2002 'a STATE LIBRARY r. o.h AVE. [..CIJTANA 59620 ^OV 0 2 2m ''"^'"'Sen^ent Bureau This raport 1« printed on p*p*r mad* from 100% racyclad poat-conaumar flbar SUMMARY On August 21, 2001, periphyton samples were collected at three stations on Cottonwood Creek near Lewistown, Montana for the purpose of assessing whether the creek is water-quality limited and in need of TMDLs . The samples were collected following DEQ standard operating procedures, processed and analyzed using standard methods for periphyton, and evaluated following modified USEPA rapid bioassessment protocols for wadeable streams. Cottonwood Creek heads in the Big Snowy Mountains but flows for most of its length through a grassland ecoregion. For this reason, Cottonwood Creek metrics were compared to biocriteria for both mountain streams and prairie streams. Cottonwood Creek supported a diverse algal flora indicating nutrient-rich waters and a stable community with very little disturbance. The presence/absence and relative abundance of algal genera and species indicate an increase in sediment, nutrients, organics, dissolved solids, and water temperatures as one proceeds downstream. When compared to biocriteria for mountain streams, diatom metrics at site 03 near the mouth of Cottonwood Creek indicated partial support of aquatic life uses and moderate impairment. The cause of this impairment was excessive siltation. However, when the diatom metrics for Cottonwood Creek were compared to criteria for plains streams, only minor impairment from organic loading was indicated at the downstream site. Other sites fully supported their aquatic life uses. The presence of the cyanobacterium Nostoc and a very large number of diatoms in the family Epithemiaceae indicate that nitrogen was likely the limiting nutrient in Cottonwood Creek. INTRODUCTION This report evaluates the biological integrity, support of aquatic life uses, and probable causes of impairment to those uses, in Cottonwood Creek near Lewistown, Montana. The purpose of this report is to provide information that will help the State of Montana determine whether Cottonwood Creek is water-quality limited and in need of TMDLs . The federal Clean Water Act directs states to develop water pollution control plans (Total Maximum Daily Loads or TMDLs) that set limits on pollution loading to water-quality limited waters. Water-quality limited waters are lakes and stream segments that do not meet water-quality standards, that is, that do not fully support their beneficial uses. The Clean Water Act and USEPA regulations require each state to (1) identify waters that are water-quality limited, (2) prioritize and target waters for TMDLs, and (3) develop TMDL plans to attain and maintain water- quality standards for all water-quality limited waters. Evaluation of use support in this report is based on the species composition and structure of the periphyton (benthic algae, phytobenthos) community at three stream sites that were sampled on August 21, 2001. The periphyton community is a basic biological component of all aquatic ecosystems. Periphyton accounts for much of the primary production and biological diversity in Montana streams (Bahls et al . 1992). Plafkin et al . (1989) and Stevenson and Bahls (1999) list several advantages of using periphyton in biological assessments: • Algae are universally present in large numbers in all streams and unimpaired periphyton assemblages typically support a large number (>30) of species; • Algae have rapid reproduction rates and short life cycles, making them useful indicators of short-term impacts; As primary producers, algae are most directly affected by physical and chemical factors, such as temperature, nutrients, dissolved salts, and toxins; Sampling is quick, easy and inexpensive, and causes minimal damage to resident biota and their habitat; Standard methods and criteria exist for evaluating the composition, structure, and biomass of algal associations; Identification to species is straightforward for the diatoms, for which there is a large body of taxonomic and ecological literature; Excessive algae growth in streams is often correctly perceived as a problem by the public. Periphyton and other biological communities reflect the biological integrity^ of waterbodies; restoring and maintaining the biological integrity of waterbodies is a goal of the federal Clean Water Act; Periphyton and other biological communities integrate the effects of different stressors and provide a measure of their aggregate impact; and Periphyton and other biological communities may be the only practical means of evaluating impacts from non-point sources of pollution where specific ambient criteria do not exist (e.g., impacts that degrade habitat or increase nutrients) . Periphyton is a diverse assortment of simple photosynthetic organisms, called algae, and other microorganisms that live attached to or in close proximity of the stream bottom. Most algae, such as the diatoms, are microscopic. Diatoms are distinguished by having a cell wall composed of opaline glass- - hydrated amorphous silica. Diatoms often carpet a stream bottom with a slippery brown film. ^ Biological integrity is defined as "the ability of an aquatic ecosystem to support and maintain a balanced, integrated, adaptive community of organisms having a species composition, diversity, and functional organization comparable to that of natural habitats within a region" (Karr and Dudley 1981) . Some algae, such as the filamentous greens, are conspicuous and their excessive growth may be aesthetically displeasing, deplete dissolved oxygen, interfere with fishing and fish spawning, clog water filters and irrigation intakes, create tastes and odors in drinking water, and cause other problems. PROJECT AREA AND SAMPLING SITES The project area is located in Fergus County near the city of Lewistown, Montana (pop. 6,368). Cottonwood Creek heads in the Big Snowy Mountains (maximum elevation 8,730 feet) and flows northwest for about 30 miles to where it enters Big Spring Creek near Hanover northwest of Lewistown. Cottonwood Creek begins in the Northern Rockies Ecoregion but flows for most of its length through the Montana Valley and Foothill Prairies Ecoregion (Woods et al . 1999). All three sampling sites are within the prairie ecoregion. The surface geology of the Cottonwood Creek watershed consists of Big Snowy dolomite and limestone in the headwaters, metamorphic rocks of the Kootenai Formation in the middle reach, and shales of the Colorado Group in the lower reach (Renfro and Feray 1972) . Vegetation is alpine tundra and spruce-fir forest in the headwaters, mixed forest and grassland in the middle reach, and mixed grassland at lower elevations (USDA 1976) . Periphyton samples were collected at three sites on August 21, 2001. The upper site (M22CTWDC01) is located about 2 miles, below the Cottonwood School at an elevation of 4,454 feet (Map 1) . The middle site (M22CTWDC02) is located below Beaver Creek at an elevation of about 3,900 (Map 2) . The lower site (M22CTWDC03) is located just above the confluence with Big Spring Creek near Hanover at an elevation of 3,700 feet (Map 2) . 4 Coordinates of the sampling sites are as follows: M22CTWDC01 46 57 46 N/109 29 02 W M22CTWDC02 47 05 28 N/109 35 57 W M22CTWDC03 47 07 34 N/109 34 18 W Land use in the Cottonwood Creek watershed is mostly livestock and wildlife grazing and recreation. Cottonwood Creek is classified B-1 in the Montana Surface Water Quality Standards METHODS Periphyton samples were collected by Rebecca Ridenour (Water Monitoring Section, MDEQ Monitoring and Data Management Bureau) following standard operating procedures of the MDEQ Planning, Prevention, and Assistance Division. Using appropriate tools, microalgae were scraped, brushed, or sucked from natural substrates in proportion to the rank of those substrates at the study site. Macroalgae were picked by hand in proportion to their abundance at the site. All collections of microalgae and macroalgae were pooled into a common container and preserved with Lugol's solution. The samples were examined to estimate the relative abundance and rank by biovolume of diatoms and genera of soft (non-diatom) algae according to the method described by Bahls (1993) . Soft algae were identified using Dillard (1999) , Prescott (1978) , Smith (1950) , and Whitford and Schumacher (1984) . These books also served as references on the ecology of the soft algae, along with Palmer (1977) . After the identification of soft algae, the raw periphyton samples were cleaned of organic matter using sulfuric acid and postassium dichromate, and permanent diatom slides were prepared using Naphrax, a high refractive index mounting medium, following Standard Methods for the Examination of Water and Wastewater (APHA 1998) . Between 428 and 454 diatom cells (856 to 908 valves) were counted at random and identified to species. The four volume series by Krammer and Lange-Bertalot (1986, 1988, 1991a, 1991b) was used as the main taxonomic and autecological reference for the diatoms. Lowe (1974), Bahls et al . (1984), van Dam et al . (1994) , and Lange-Bertalot (1996) were also used as ecological references for the diatoms. The diatom proportional counts were used to generate an array of diatom association metrics (Table 1) . A metric is a characteristic of the biota that changes in some predictable way with increased human influence (Barbour et al . 1999). Metric values from Cottonwood Creek were compared to numeric biocriteria or threshold values developed for streams in the Rocky Mountain and Great Plains Ecoregions of Montana (Tables 2 and 3) . These criteria are based on metric values measured in least-impaired reference streams (Bahls et al . 1992) and on metric values measured in streams that are known to be impaired by various sources and causes of pollution (Bahls 1993) . The criteria in Tables 2 and 3 distinguish among four levels of impairment and three levels of aquatic life use support: no impairment or only minor impairment (full support) ; moderate impairment (partial support) ,- and severe impairment (nonsupport) . These impairment levels correspond to excellent, good, fair, and poor biological integrity, respectively. Quality Assurance. Several steps were taken to assure that the study results are accurate and reproducible. Upon receipt of the samples, station and sample information were recorded in a laboratory notebook and the samples were assigned a unique number compatible with the Montana Diatom Database, e.g., 2196-01. The first part of this number (2196) designates the sampling site (Cottonwood Creek below Beaver Creek) ; the second part of this number (01) designates the number of periphyton samples that have been collected at this site to date for which data have been enter??d into the Montana Diatom Database . Sample observations and analyses of soft (non-diatom) algae were recorded in a lab notebook along with station and sample information provided by MDEQ . A portion of the raw sample was used to make duplicate diatom slides. After completing the diatom proportional count, the slide used for the count will be deposited in the University of Montana Herbarium in Missoula. The other slide will be retained by Hannaea in Helena. Station information, sample information, and diatom proportional count data have been entered into the Montana Diatom Database, maintained on a PC by Hannaea in Microsoft Access. RESULTS AND DISCUSSION Results are presented in Tables 4, 5, and 6, which are located near the end of this report following the References section. Spreadsheets containing completed diatom proportional counts, with species' pollution tolerance classes (PTC) and percent abundances, are attached as Appendix A. SAMPLE NOTES M22CTWDC01. The Oscillatoria in this sample comprised a large, macroscopic mat; many loose filaments were also present M22CTWDC02. The Cladophora in this sample was senescent. NON- DIATOM ALGAE All three sites supported a normal algal flora consisting of green algae, diatoms, and cyanobacteria (Table 4) . Unattached, filamentous green algae ranked first in biovolume at all three sites: Spirogyra ("pond scum") at sites 01 and 02, and Mougeotia at site 03. A mat-forming species of Oscillatoria ranked second at site 01 followed by diatoms. Diatoms ranked second in biovolume at sites 02 and 03, where another filamentous green- - Oedogonium- -ranked third. An abundance of unattached filamentous greens in Cottonwood Creek is an indication of slower current velocities and elevated nutrient concentrations. Audouinella, a red alga that prefers cool waters and lower levels of nutrients, was common at site 01, occasional at site 02, and absent at site 03 (Table 4). Nostoc, a nitrogen- fixer that also prefers low nutrient levels and cool water temperatures, was present at site 01 but absent from the other two sites. The appearance of Euglena at site 03 (Table 4) may signal an increase in organic loading at this site. Euglena is very tolerant of decomposing organic matter. The appearance of Merismopedia and Rivularia at site 03 indicates an increase in dissolved solids here. AnaJbaena, which prefers warmer waters, was absent from site 01, occasional at site 02, and frequent at site 03, indicating an increase in water temperatures downstream. However, Tribonema, which is a cool water genus, was also present at site 03. 8 DIATOMS All of the major diatom species in Cottonwood Creek are either tolerant of a wide range of trophic conditions- -from oligotrophic to eutrophic- -or produce their largest populations only in stronger mesotrophic to eutrophic waters (Tables 5 and 6) . Two of these major species- -Cocconeis pediculus and Epithemia sorex--are epiphytes with one concave valve surface that is so adapted to living attached to filaments of green algae . All three sites on Cottonwood Creek had excellent diatom diversity, species richness, and equitability (Table 5 and 6). The disturbance index (% Achnanthidium winutissimum) was low at all sites, indicating very little chemical, physical, or biological disturbance and high community stability. The pollution index indicated minor impairment but full support of aquatic life uses at all three sites when compared to biocriteria for mountain streams in Table 2 (Table 5) . When compared to criteria for plains streams in Table 3, the pollution index indicated minor impairment only at site 03, and no impairment at sites 01 and 02 (Table 6) . The siltation index indicated minor impairment at sites 01 and 02, and moderate impairment with partial support of aquatic life uses at site 03 when judged against biocriteria for mountain streams in Table 2 (see Table 5) . The siltation index increased in a downstream direction. When compared to the criteria for plains streams, the siltation index indicated no impairment and full support of aquatic life uses at all three sites (Table 6) . The siltation index is the percentage of diatoms in the genera Navicula, Nitzschia, and Surirella. Diatoms in these genera are motile and capable of maintaining their position on top of aggrading substrates. A small number of teratological cells was counted at sites 02 and 03, indicating minor impairment of aquatic life uses. Salinity, heavy metals, and organic loading are three of several factors that have been shown to cause diatom deformities. No diatoms in the family Epithemiaceae were counted at site 01 (Tables 5 and 6) . On the other hand, exceptionally large numbers of diatoms in this family were recorded at sites 02 and 03. Diatoms in the family Epithemiaceae harbor nitrogen-fixing cyanobacteria within their cells. Hence, the large number of diatoms in this family indicate that nitrogen is likely the limiting nutrient at sites 02 and 03. Adjacent sites on Cottonwood Creek shared between 40% and 50% of their diatom floras (Similarity Index, Tables 5 and 6) . This level of similarity indicates only minor change in environmental conditions between adjacent sites. 10 REFERENCES APHA. 1998. Standard Methods for the Examination of Water and Wastewater. 20th Edition. American Public Health Association, Washington, D.C. Bahls, L.L. 1979. Benthic diatom diversity as a measure of water quality. Proc . Mont. Acad. Sci . 38:1-6. Bahls, L.L. 1993. Periphyton Bioassessment Methods for Montana Streams (Revised) . Montana Department of Health and Environmental Sciences, Helena. Bahls, L.L. 1999. Effects Of An Oil Spill on The Composition and Structure of the Periphyton Community in Casino Creek and Big Spring Creek near Lewistown, Montana. Prepared for the Montana Department of Environmental Quality, Helena, Contract No. 200012. Bahls, L.L., E.E. Weber, and J. 0. Jarvie . 1984. Ecology and Distribution of Major Diatom Ecotypes in the Southern Fort Union Coal Region of Montana. U.S. Geological Survey Professional Paper 1289, U.S. Government Printing Office, Washington . Bahls, L.L., Bob Bukantis, and Steve Tralles . 1992. Benchmark Biology of Montana Reference Streams . Montana Department of Health and Environmental Sciences, Helena. Barbour, M.T., J. Gerritsen, B.D. Snyder, and J.B. Stribling. 1999. Rapid Bioassessment Protocols for Use in Streams and Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and Fish. Second Edition. EPA/841-B-99-002 . U.S. EPA, Office of Water, Washington, D.C. Dillard, G.E. 1999. Common Freshwater Algae of the United States. J. Cramer, Berlin. Johansen, J.R. 1999. Diatoms of Aerial Habitats. Chapter 12 in Stoermer, E.F., and J. P. Smol (eds.). The Diatoms, Cambridge University Press, New York. Karr, J.R., and D.R. Dudley. 1981. Ecological perspectives on water quality goals. Environmental Management 5:55-69. Krammer, K., and H. Lange-Bertalot . 1986. Bacillariophyceae, Part 2, Volume 1: Naviculaceae . In Ettl, H., J. Gerloff, H. Heynig, and D. Mollenhauer (eds.). Freshwater Flora of Middle Europe. Gustav Fischer Publisher, New York. 11 Krammer, K., and H. Lange-Bertalot . 1988. Bacillariophyceae, Part 2, Volume 2: Bacillariaceae, Epithemiaceae, Surirellaceae . In Ettl, H., J. Gerloff, H. Heynig, and D. Mollenhauer (eds.), Freshwater Flora of Middle Europe. Gustav Fischer Publisher, New York. Kraininer, K., and H. Lange-Bertalot. 1991a. Bacillariophyceae, Part 2, Volume 3: Centrales, Fragilariaceae, Eunotiaceae. In Ettl, H., J. Gerloff, H. Heynig, and D. Mollenhauer (eds.). Freshwater Flora of Middle Europe. Gustav Fischer Publisher, Stuttgart. Krammer, K., and H. Lange-Bertalot. 1991b. Bacillariophyceae, Part 2, Volume 4: Achnanthaceae, Critical Supplement to Kavicula (Lineolatae) and Gomphonema, Complete List of Literature for Volumes 1-4. In Ettl, H., G. Gartner, J. Gerloff, H. Heynig, and D. Mollenhauer (eds.). Freshwater Flora of Middle Europe. Gustav Fischer Publisher, Stuttgart. Lange-Bertalot, Horst . 1979. Pollution tolerance of diatoms as a criterion for water quality estimation. Nova Hedwigia 64:285-304. Lange-Bertalot, Horst. 1996. Red list of limnic diatoms from Germany. Schr.-R. f. Vegetationskde . , H. 28, pp. 633-677. BfN, Bonn-Bad Godesberg. Lowe, R.L. 1974. Environmental Requirements and Pollution Tolerance of Freshwater Diatoms. EPA-670/4-74-005 . McFarland, B.H., B.H. Hill, and W.T. Willingham. 1997. Abnormal Fragilaria spp . (Bacillariophyceae) in streams impacted by mine drainage. Jour, of Freshwater Ecology 12 ( 1) : 141-149 . Palmer, CM. 1977. Algae and Water Pollution: An Illustrated Manual on the Identification, Significance, and Control of Algae in Water Supplies and in Polluted Water. EPA-600/9-77-036. Plafkin, J.L., M.T. Barbour, K.D. Porter, S.K. Gross, and R.M. Hughes. 1989. Rapid Bioassessment Protocols for Use in Rivers and Streams: Benthic Macroinvertebrates and Fish. EPA 440-4-89-001. Prescott, G.W. 1978. How to Know the Freshwater Algae. Third Edition. Wm. C. Brown Company Publishers, Dubuque, Iowa. Renfro, H.B., and D.E. Feray. 1972. Geological Highway Map of the Northern Rocky Mountain Region. American Association of Petroleum Geologists, Tulsa, Oklahoma. 12 Smith, G.M. 1950. the Fresh-Water Algae of The United States. McGraw-Hill Book Company, New York. Stevenson, R.J., and L.L. Bahls. 1999. Periphyton Protocols. Chapter 6 in Barbour, M.T., J. Gerritsen, B.D. Snyder, and J.B. Stribling. Rapid Bioassessment Protocols for Use in Streams and Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and Fish. Second Edition. EPA/841-B-99- 002. U.S. EPA, Office of Water, Washington, D.C. USDA. 1976. Climax Vegetation of Montana (map). U. S. Department of Agriculture, Soil Conservation Service, Cartographic Unit, Portland. van Dam, H., A. Mertens, and J. Sinkeldam. 1994. A coded checklist and ecological indicator values of freshwater diatoms from the Netherlands. Netherlands Journal of Aquatic Ecology, 28 (1) : 117-133 . Whitford, L.A., and G.J. Schumacher. 1984. A Manual of Fresh- Water Algae (Revised) . Sparks Press, Raleigh, North Carolina. Whittaker, R.H. 1952. A study of summer foliage insect communities in the Great Smoky Mountains. Ecological Monographs 22:1-44. Woods, A.J., Omernik, J.M., Nesser, J. A., Shelden, J., and Azevedo, S.H. 1999. 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O JJ a 5h D u c; a 0 rH •H u a o C ro •H C g 5h JJ d X O 73 0 13 ro fO 0 0 o H pq M M o CO c/) W S CO o fc ^ 0) CO a, s ^ ugcfljjjj'pO'HS N u u JJ 1 1 0 (0 1 o •rl rt 0^ 0 x; >, £! ^ JJ SHJJQJiHoVoU H S •H •H m 0 CO to g M rH 3 03 x: QJ > QJ cn -^ • U JJ i*H -H > ■ U a rO JJ m g (U QJ ^ ^ 1 1 n)gCQ03GOjJ CTiO n (C G QJ -rH 03 II n -n QJ 0 o\o rH 1 03 ■H ^ 4:^ • 0) S w 0 0 0 0 C7\ cn JJ H QJ U 0 rH . r-( W JJ i^ C r-i 0 0 rH rH cn cn S,Vh-H iHJJO QJoVO g c CQ 03 UH 0 • 0 - ^ -H XlJJQJCntNCQ n3 -H (V h d) ex. ^ u A V A JJ Cf] ■ CQ C CI to QJ -H C >, JJ QJUCQjJCQXlin 03 B m 0 n JJ C m 1 fMgOQJ-H03JJA-~^| If^OSCQGSQJ Q)0 fj CQ CQ rH rH QJ tJIrH C i-l -H :3 G 03 0) 0 0 a^ 0 cn cn 0 ft JJ JJ QJ C -H • . ^1 03 W U -H U in IT) CTl 0 ^ -* ~] 03 m - dl •• G HH QJ >gjJ05CQ03 -H rH U QJ QJ 0 a V A Lttaker e on th diatom ndance e strea have a d to gu dy site inor ch similar C XI 0 JH Cli Q CO (U ffl W JJ 0) W -T3 fO J-l U -Ji Ti >, m 0 0) QJ QJ jj S g u-i jq i4H -H jj 1 t •H 0 g 0 u c CTl 0 cn 0 cn 0 r:-LJGGg>.QJGgCQ $-HQJX103rHCQjJ -H C^C0Q)03CQrHGCQ -Ti >-i C JJ Cn 3 OJ 3 ro n n rs (N (N Cn-H fO c s a 0 A V dJ -H -H CO u S 03 CQ JJ JJ -Cl JJ ^rH JJJJQ)MQJJJ03>, .TLlHXlQJJJG Q)0QJ CM fO 0) •H 0 U M u Qj-H G l_,JJ U QJOUrH> ^C>iiHGCnCQ03«4H ^ 0 JJ QJ 0 rH -n II -H U -H a rH 03 -O iH r-H OlX: iH 03 X 1 1 (C 3 JJ rH £! 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JJ QJ 0 3 T3 (N H (N H H rH 03 - to rH C A V <, 03 Qjjj-H c--^>,in g n iH CQ QJ iH 1 0 tJliw g G QJ 0 - Sh CQ >, rH M w Cn C 0 vh QJ c m a, [ndex ite t he de sum 0 both viron commo recov ; 40. loras 0 V^ -H •w JJ m ^-1 >i ^ m 3 0 JJ G 1 1 OS 14H •H >^ 0 a^ 0 cr\ 0 cr\ 0 ■H rH 03 CQ QJ G cr> 0 cn 0 cn 0 CQ JJ 0 G QJ IW Sh m c en iH T3 G . ■ Similarity re a study c measures and is the is common t taries or e: m floras in painnent or s, no Chang dissimilar Q) u m G Q) G m n n m r^ CM CN JJ :3 JJ -H > M j:: A V •H JJ C JJ -H CO QJ M 03 0 03 Q — JJ JJ U C 2 Vh ^H fO Q) rH -^ JJ rH QJ u 0 U U JJ 03 >i G 03 CQ JJ r-i 0 a QJ (U U • U JJ Q) M ^3 G rH G a n > 0 n •H -rl g Id "\ JJ QJ 3 JJ ■rH 3 0 rH JJ QJ a tn Sh S iJ CQ sh r-{ :jH U 2 CO S 03 ^1 CO a 0) 0 Cn-H 03 CQ 0 rH\ 0 \-H 0 \ G n)03-rlCQ 3Og03 ^ Q4U Q)JJX!JJ-H ^HJJ r:^gjJjJ03-rlOi O03 ■^ 0 QJ-rIX; iH-rlMHrHX; rH rH QJ 03 2 Q) 0 QJ QJ a T) rH iH JJ a iH CQ ^ 0 JJ a in Q u G a 0 rH •H M a 0 G (6 •H G g Sh JJ 13 X 0 3 0 3 03 03 G 0 0 Eh CQ M M 0 CO CO W S CO 0 fc Ct, a CO a s w CJgCQjJjJTJOyHS Table 4. Relative abundance of cells and rank by biovolume of diatoms and genera of non-diatom algae in periphyton samples collected from Cottonwood Creek on 8/21/01: d = dominant; a = abundant; f = frequent; c = common; o = occasional; r = rare. • Relative Abundance and Rank Taxa M22CTWDC01 M22CTWDC02 M22CTWDC03 Chlorophyta (green algae) Anki s trodesmus o c Cladophora c/4 Closterium r o r Cosmarium c/5 o Mougeotia 0/5 d/1 Oedogonium f/3 f/3 Oocyst is r Pediastrum r r Rhizocloniuin 0/7 Scenedesmus o o Spirogyra a/1 a/1 f/4 Zygnema c/8 Euglenophyta (euglenoid algae) Euglena r Chrysophyta (golden algae) Diatoms a/3 a/2 a/2 Tribonema o Rhodophyta (red algae) Audouinella c/4 o Cyanophyta (cyanobacteria) ^ Amphithrix 0/6 Anahaena o f/5 Calothrix r r o Lyngbya f/6 Merismopedia o Nostoc o Oscillatoria a/2 o Phorwidium 000 Rivularia o/9 Formerly known as blue-green algae Table 5. Percent abundance of major diatom species^ and values of selected diatom association metrics for periphyton samples collected from Cottonwood Creek on 8/21/01. Underlined values indicate good biological integrity, minor impairment, and full support of aquatic life uses; bold values indicate fair biological integrity, moderate impairment, and partial support of aquatic life uses,- all other values indicate excellent biological integrity, no impairment, and full support of aquatic life uses when compared to criteria for mountain streams in Table 2 . Species/Metric Percent Abundance/Metric Values (Autecology)^ M22CTWDC01 M22CTWDC02 M22CTWDC03 Achnanthidiuin minutissimum (tol] Cocconeis pediculas (eu) Cymbella af finis (eu) Encyonopsis microcephala (tol) Epithemia sorex (eu) Gowphonewa parvulum (tol) Navicula capita toradiata (eu) Navicula cryptotenella (tol) Nitzschia frustulum (eu) Nitzschia palea (eu) Nitzschia paleacea (eu) Symedra ulna (eu) Cells Counted Total Species Species Counted Species Diversity Percent Dominant Species Disturbance Index Pollution Index Siltation Index Percent Abnormal Cells Percent Epithemiaceae Similarity Index^ 12 .67 7.15 4.55 6.82 3.50 8 .45 3.41 0.23 9 .59 0.22 0.00 17.60 14.57 3 .20 5.28 1.98 3 .20 1.54 5.83 5 .02 2.75 8.25 5.13 4 .34 5.06 11.07 0 .46 1.10 6.99 12 .33 4.51 12.94 438 454 428 60 75 68 59 61 59 4. .60 4.73 4.52 12. .67 17.60 14.57 12. ,67 7.15 4.55 2. .34 2.40 2.15 26. .60 36.52 43.17 0. ,00 0.22 0.12 0. .00 18.37 20.63 43, .67 48, .56 A major diatom species is one that accounts for 3% or more of the cells in one or more samples of a sample set Autecology eu: best growth in stronger mesotrophic to eutrophic waters tol: tolerant of a wide range of trophic status from oligo- to eutrophic waters without discernible preference The percent community similarity between CTWDC 01 and CTWDC 03 was 38.04%. Table 6. Percent abundance of major diatom species^ and values of selected diatom association metrics for periphyton samples collected from Cottonwood Creek on 8/21/01. Underlined values indicate good biological integrity, minor impairment, and full support of aquatic life uses,- all other values indicate excellent biological integrity, no impairment, and full support of aquatic life uses when compared to criteria for prairie streams in Table 3 . Species/Metric (Autecology) ^ Percent Abundance/Metric Values M22CTWDC01 M22CTWDC02 M22CTWDC03 Achnanthidium minutissimum (tol) Cocconeis pediculus (eu) Cymbella af finis (eu) Encyonopsis microcephala (tol) Epithemia sorex (eu) Gomphonema parvulum (tol) Navicula capitatoradiata (eu) Navicula cryptotenella (tol) Nitzschia frustulum (eu) Nitzschia palea (eu) Nitzschia paleacea (eu) Synedra ulna (eu) Cells Counted Total Species Species Counted Species Diversity Percent Dominant Species Disturbance Index Pollution Index Siltation Index Percent Abnormal Cells Percent Epithemiaceae Similarity Index^ 12.67 7.15 4.55 6.82 3.50 8.45 3.41 0.23 9.59 0.22 0.00 17.60 14.57 3.20 5.28 1.98 3.20 1.54 5.83 5.02 2.75 8.25 5.13 4.34 5.06 11.07 0.46 1.10 6.99 12.33 4.51 12.94 438 454 428 60 75 68 59 61 59 4.60 4.73 4.52 12.67 17.60 14.57 12.67 7.15 4.55 2.34 2.40 2.15 26.60 36.52 43.17 0.00 0.22 0.12 0.00 18.37 20.63 43, .67 48, .56 ^ A major diatom species is one that accounts for 3% or more of the cells in one or more samples of a sample set ^ Autecology eu: best growth in stronger mesotrophic to eutrophic waters tol: tolerant of a wide range of trophic status from oligo- to eutrophic waters without discernible preference ' The percent community similarity between CTWDC 01 and CTWDC 03 was 38.04%. APPENDIX A: DIATOM PROPORTIONAL COUNTS Cottonwood Creek at County Road (CTWDC 01) 10/21/01 Sample Genus/Spgcies/Vitfiftlty Poliuti«>n Toleraftce C^ft Cottnl Percent 21 9501 Achnanlhes lance Qlala_ 219501 Achnanltiessp. 219501 Achnanthidium affine 219501AchnanlhidiunLbiasQietlianuirL _ 219501 Achnanthidium minutissimum 2 1,9501 Amphipleura pellucida 3501 Amphora libyca 21 9501 Aulacoaeira_distans_ 219501 Aulacoseira islandica , 21 950 1 .CaloneisJjacillunL 219501 Cocconeis placentula -2Q. JLLL JM. AQ. JL23 JL23 JL22 .2^ 12.67 ^im JL34 JL23 JL23 0.00 AAA 11950 1 Cyclotella meneghiniana 219501 Cymbella affinis 219501,Cymbella hebridica 21 9501 Cymbella mexicana _2ia5Ql Cymbella sp. JA. A JLll _&A5. 0.11 JLll JLll 21 9501 Diatoma moniliformis JJ4. JLM J^195Q1 Diploneis oblongella 19501 Encyonema brehmii 219501 Encyonema silesiacum 219501 Encyonopsis cesatii -4. JZl. jL4e ,^jia JLM JL23 219501 Encyonopsis microcephala _84. _9^ 219501 Fragilaria capucina JLM n 9501 Fragilaria vaucheriae 219501Gomphonema angustatum 219501iGomphonema minutum ^. JLM JL46 Am 219501|Gomphonema olivaceum _ 21 950liGomphonema parvulum U 9501 Gomphonema pumilum 219501 Navicula capitatoradiata 219501 Navicula cryptocephala .28. AI. .28. _Q^ A2Q JLS4 A2Q JL91 219501 Navicula cryptotenella AA. _5J32 219501 Navicula radiosa .2195QlJ^avicula reichardtiana 21 9501 Navit^ula^trofimiL 219501 Navicula tripunctata 21 9501 Navicula trivialis _11 _QM JL26 JLM JL52 JL23 19501 Navicula veneta 219501. Navicula viridula 50 1 ,Nitzschiajcicularis_ 2195Q1[Nitzschia angustata JL2a 0.11 JL46 JLM 219501 Nitzschia angustatula JL23 _21S5Ql4Nitzschia.apiculala_ 0.23 AJm L95Ql.Nitzschiidissipata_ 219501J^Jitzschja fonticola 219501 [Nitzschia incognita _219M1 Nitzschia linearis J25. AA. JLSa JL91 ±m 219501 Nitzschia palea J8. A3A „219i01 ^2195.01 ^19501 ^215501 Nitzschia paieacea Nitzschia_pusjlla_ Nitzschia recta Nitzschia sociabilis 21 9501, Nitzschia supralitorea -213501 jReimeria sinuata 19501,Stauroneis smilhiL 2195Ql,Staurosira construens 219501 Staurosirella pinnata JL46 JL22 0.11 JL23 JL23 JLll 046 JLfiS _Q^ .19501 Syjiedr_ai:umpens_ 219501 Synedra ulna 108 J1A& 12.33 Page 1 Cottonwood Creek below Beaver Creek (CTWDC 02) 10/21/01 iSample GmwsiSpeciesfVatieW Pollutioa IjDierance C^s CoitT^ ^■w:::::Percem;:: ;;:;:-: 219601 Achnanthes lanceolata 2 3 0.33 219601 Achnanthidium minutissimum 3 65 7.15 21960l[Amphipleura pellucida 2 1 0.11 21 9601 [Amphora inariensis 3 1 0.11 21 9601 Amphora libyca 3 1 0.11 21 9601 Amphora pediculus 3 12 1.32 219601 Aulacoseira distans 3 3 0.33 219601 Aulacoseira islandica 3 2 0.22 219601 Caloneis bacillum 2 5 0.55 219601 Caloneissilicula 2 2 0.22 219601 Cocconeis pediculus 3 62 6.82 219601 Cocconeis placentula 3 37 4.07 219601 Cyclotella meneghiniana 2 9 0.99 219601 Cylindrotheca gracilis 2 0 0.00 219601 Cymbella affinis 3 31 3.41 219601 Diatoma moniliformis 2 10 1.10 219601 Diatoma vulgaris 3 1 0.11 219601 Diplonels oblongella 3 0 0.00 219601 Diplonels parma 3 2 0.22 219601 Encyonema auerswaldii 2 0 0.00 219601 Encyonema brehmii 2 0 0.00 219601|Encyonema silesiacum 2 5 0.55 219601 Encyonopsis microcephala 2 2 0.22 219601 Epithemia sorex 3 160 17.60 219601 Epithemia turgida 3 0 0.00 219601 Gomphonema minutum 3 23 2.53 219601 Gomphonema parvulum 1 48 5.28 219601 Gomphonema pumilum 3 2 0.22 219601 Gomphonema truncatum 3 2 0.22 219601 Gyrosigma acuminatum 3 1 0.11 219601 Navicula acceptata 2 0 0.00 219601 Navicula capitatoradiata 2 14 1.54 219601 Navicula can 2 2 0.22 219601 Navicula cryptotenella 2 25 2.75 219601 Navicula elginensis 3 0 0.00 219601 Navicula gregaria 2 2 0.22 219601 Navicula lenzii 2 12 1.32 219601 Navicula menisculus 2 0 0.00 219601 Navicula minima 1 2 0.22 219601 Navicula peregrina 2 1 0.11 219601 Navicula pupula 2 7 0.77 219601 Navicula pygmaea 2 0 0.00 219601 Navicula reichardtiana 2 12 1.32 219601 Navicula tripunctata 3 8 0.88 219601jNaviculatrivialis 2 4 0.44 219601[Navicula viridula 2 0 0.00 219601 Nitzschia acicularis 2 16 1.76 Page 1 Cottonwood Creek below Beaver Creek (CTWDC 02) 10/21/01 ::: Sample I Oenu«/Sp«llii(liiiii^Pi ^llollii6iilii^iii6'C^ count I ¥1PPIH 219601 Nitzschia amphibia 2 0 0^ 219601 Nitzschia angustata 2 3 0.33 219601 Nitzschia angustatula 2 2 0.22 219601 Nitzschia capitellata 2 2 0.22 219601 Nitzschia dissipata 3 36 3.96 219601 Nitzschia frustulunn 2 75 8.25 219601 Nitzschia gracilis 2 8 0.88 219601 Nitzschia heufleriana 3 3 0.33 219601 Nitzschia incognita 2 15 1.65 219601 Nitzschia liebetruthii 2 0 0.00 219601 Nitzschia linearis 2 0 0.00 219601 Nitzschia palea 1 46 5.06 219601 Nitzschia paleacea 2 10 1.10 219601 Nitzschia pusilla 1 1 0.11 219601 Nitzschia sociabilis 2 5 0.55 219601 Nitzschia solita 1 8 0.88 219601 Nitzschia vermicularis 2 11 1.21 219601 Reimeria sinuata 3 4 0.44 219601 Rhoicosphenia curvata 3 0 0.00 219601 Rhopalodia gibba 2 6 0.66 219601 Rhopalodia operculata 1 1 0.11 219601 Simonsenia delognei 2 2 0.22 219601 Staurosira construens 3 10 1.10 219601 Stephanodiscus hantzschii 2 6 0.66 219601 Surirella minuta 2 2 0.22 219601 Synedra acus 2 10 1.10 219601 Synedra rumpens 2 7 0.77 21960rSynedra ulna 2 41 4.51 Page 2 Cottonwood Creek at mouth near Hanover (CTWDC 03) 10/21/01 1 Sample GenttS/Speci^isA^amty Pottution TbiefaiJce Ciass CcHtnl Percent 219701 Achnanthes lanceolata 2 1 0.12 219701 Achnanthidium minutissinnum 3 39 4.55 219701 Amphora libyca 3 2 0.23 219701 Amphora pediculus 3 7 0.82 219701 Cocconeis pediculus 3 30 3.50 219701 Cocconeis placentula 3 11 1.28 219701 Cyclotella meneghiniana 2 9 1.05 219701 Cymatopleura solea 2 0 0.00 219701 Cymbella affinis 3 2 0.23 219701 Cymbella cistula 3 0 0.00 219701 Diatoma moniliformis 2 1 0.12 219701 Encyonema silesiacum 2 1 0.12 219701 Encyonopsis microcephala 2 0 0.00 219701 Epithemia adnata 2 3 0.35 219701 Epithemia sorex 3 125 14.57 219701 Epithemia turgida 3 4 0.47 219701 Fragilaria capucina 2 12 1.40 219701 Fragilaria vaucheriae 2 1 0.12 219701 Gomphonema minutum 3 12 1.40 219701 Gomphonema parvulum 1 17 1.98 219701 Melosira varians 2 7 0.82 219701 Navicula acceptata 2 2 0.23 219701 Navicula bryophila 3 2 0.23 219701 Navicula capitatoradiata 2 50 5.83 219701 Navicula clementioides 3 0 0.00 219701 Navicula kotschyi 2 1 0.12 219701 Navicula menisculus 2 5 0.58 219701 Navicula minima 1 2 0.23 219701 Navicula omissa 1 2 0.23 219701 Navicula pupula 2 1 0.12 219701 Navicula radiosa 3 0 0.00 219701 Navicula recens 2 1 0.12 219701 Navicula reichardtiana 2 17 1.98 219701 Navicula trivialis 2 2 0.23 219701 Navicula veneta 1 8 0.93 219701 Nitzschia acicularis 2 6 0.70 219701 Nitzschia agnita 1 16 1.86 219701 Nitzschia amphibia 2 5 0.58 219701 Nitzschia angustata 2 0 0.00 219701 Nitzschia angustatula 2 0 0.00 219701 Nitzschia apiculata 2 3 0.35 219701 Nitzschia communis 1 0 0.00 219701 Nitzschia dissipata 3 19 2.21 219701 Nitzschia frustulum 2 44 5.13 219701 Nitzschia gracilis 2 4 0.47 219701 Nitzschia incognita 2 9 1.05 219701 Nitzschia linearis 2 5 0.58 Page 1 Cottonwood Creek at mouth near Hanover (CTWDC 03) 10/21/01 iSSl«iPPPSPiS^iStMspcliilS?ail«^ mmmmi^mmmmm Count Percent 219701 Nitzschia palea 1 95 11.07 219701 Nitzschia paleacea 2 60 6.99 219701 Nitzschia recta 3 1 0.12 219701 Nitzschia sigmoidea 3 0 0.00 219701 Nitzschia sociabilis 2 2 0.23 219701 Nitzschia solita 1 6 0.70 219701 Nitzschia vermicularis 2 2 0.23 219701 Pleurosigma delicatulum 2 1 0.12 219701 Reimeria sinuata 3 15 1.75 219701 Rhoicosphenia curvata 3 4 0.47 219701 Rhopalodia brebissonii 1 2 0.23 219701 Rhopalodia gibba 2 42 4.90 219701 Rhopalodia operculata 1 1 0.12 219701 Simonsenia delognei 2 3 0.35 219701 Stauroneis smithii 2 2 0.23 219701 Staurosirella pinnata 3 4 0.47 219701 Stephanodiscus hantzschii 2 1 0.12 219701 Synedra acus 2 14 1.63 219701 Synedra famelica 2 2 0.23 219701 Synedra filiformis 3 2 0.23 219701 Synedra ulna 2 111 12.94 Page 2