Newsletter

Volume 7, Number 1
January - February 1990

At the Arboretum

One of the winter highlights at the
Arboretum is our Greenhouse. Seen by
many as a tropical island in a sea of
winter, it gives visitors a refreshing taste
of warmer, greener days.

During February and March the tropical
unit is the main attraction. The Kolker
Begonia Collection comprises approxi-
mately 20 varieties of begonia, all in
flower at this time. Orchids are starting to
bloom, followed by Hoyas in mid- to late-
March. The grapefruit-sized ponderosa
lemons weigh down their parent tree.
Everywhere — next to the waterfall, in the
cactus collection, on the side benches,
hanging from the ceiling beams — there
are plants with bright colors, unusual
seeds and interesting textures.

The Greenhouse is open during
Arboretum hours. Admission is by free
visitor permit from the Gifford House.
Come visit!

The IES Newsletter is published by the
Institute of Ecosystem Studies at the Mary
Flagler Cary Arboretum. Located in
Millbrook, New York, the Institute is a
division of The New York Botanical
Garden. All newsletter correspondence
should be addressed to the Editor.

Gene E. Likens, Director
Joseph S. Warner, Administrator
Alan R. Berkowitz, Head of Education

Editor: Jill Cadwallader
Printing: Central Press

INSTITUTE OF ECOSYSTEM STUDIES
The New York Botanical Garden
Mary Flagler Cary Arboretum
Box AB

Millbrook, NY 12545
(914)677-5343

Dr. George Woodwell on
Global Warming

Dr. George Woodwell answers students' questions at the Institute of Ecosystem Studies.

This spring, as you travel about (in an
energy-efficient car), notice how much
greener the trees and shrubs are 100 to
160 kilometers (60-100 miles) south of
your home. If predictions about global
warming come true, in another ten years
that climatic zone to the south may have
become yours.

Dr. George M. Woodwell, well known for
his long-term studies of climatic change,
recently shared his insights with scientists
and students at the Institute of Ecosystem
Studies. Dr. Woodwell is the founder and
director of the Woods Hole Research
Center (Massachusetts), an institute for
global environmental research. A biologist
and ecologist, he has done research on the
ecological effects of ionizing radiation, on
atmospheric carbon dioxide and on nutrient
cycling. He is particularly interested in
global warming and in the management of
renewable resources. On December 15th,
IES staff and members of the public filled
the Plant Science Building lecture area for
the concluding program in the fall IES
Scientific Seminar Series, a talk by
Dr. Woodwell on climatic warming.

Just prior to that seminar, Dr. Woodwell
met with 25 high school students who
are participating in an environmental
seminar program sponsored by the
Gifted Resource Center of the Dutchess
County BOCES (Board of Cooperative
Educational Services).

Since the middle of the last century, there
has been a 25% increase in the amount of
carbon dioxide in the Earth’s atmosphere.
This increase results primarily from human
activities, especially the burning of fossil
fuels and the destruction of forests, that
release more carbon dioxide than can be
removed by plant photosynthesis or

absorbed by the oceans. The build-up of
atmospheric carbon dioxide traps heat
radiating from Earth, a phenomenon that
has become known as the “greenhouse
effect.” Temperatures may increase
approximately 1° C (1.8° F) each decade if
carbon dioxide continues to increase at its
present rate.

After a short introduction to the subject of
global warming, Dr. Woodwell invited
questions from the students. A sampling:

What would be the result if fossil fuel use
and deforestation stopped now?

Even if we could stop the build-up of
carbon dioxide now, we’re committed to a
1° C increase as we experience the full
effects of the heat-trapping gases already
present. Immediate measures to stabilize
atmospheric carbon dioxide levels will
prevent an even greater increase in the
carbon burden.

A major user of fossil fuels is the car.

What can be done to improve
the situation?

Three to five billion tons of carbon are
released into the atmosphere annually by
the burning of fossil fuels, and it is this
quantity that we want to get rid of. We
should make fossil fuels more efficient and
have a large national tax on fossil fuels.
Reforestation would reduce the scale of the
problem as well.

What are alternate sources of energy?

Geothermal, tapping the Earth’s heat, as
is done in Reykjavik, Iceland; and the
solar-powered electrolysis of water, split-
ting molecules into hydrogen and oxygen
and then burning the hydrogen. Hydrogen
has been used as a fuel in demonstration
models of Mercedes and BMW cars.

continued on page 4

A Rainforest Journal, by Jill Cadwallader, IES Program Specialist in Public Information

Just across the eastern cordillera of the
Andes Mountains in Ecuador is the
western edge of the Amazon Basin, whose
vast rainforest extends 2,600 kilometers
(1,600 miles) across South America to the
Atlantic Ocean. Recently, a group of
scientists and naturalists went on a research
expedition to Ecuador’s rainforest to learn
more about a remote lake in the north-
eastern part of the country. I was fortunate
to be part of that group.

Jan. 3rd: Our group of nine met at
J.F. Kennedy International Airport for the
seven-hour flight to Quito, Ecuador, the
oldest capital city in South America.

Jan. 5th: The half-hour flight from Quito
to the rainforest frontier town of Lago
Agrio — growing rapidly as a result of
Ecuador’s oil industry — took us past
Mount Cayambe, a volcanic peak topped
by the only glacier to cross the Equator.
This is the dry season, and the dusty bus
ride from the Lago Agrio airport made the
Rio Aguarico a welcome sight. The
Aguarico flows east to join the Rio Napo,
which in turn meets the Amazon River near
Iquitos, Peru; it would be home for the next
two days. Scientific gear and luggage went
in one large motorized dugout canoe while
we rode in a second.

Jan. 7th: After 150 km (90 mi.) of river
travel we left the canoes at a military
outpost and, with our guide and crew of
seven, hiked to Zancudo Cocha. Zancudo
Cocha ( zancudo is Spanish for mosquito,
and cocha is an Indian word for oxbow
lake) is a small oval, tea-colored lake deep
in primary forest. The trail had logs across
it at regular intervals, and we learned later
that these were the rollers used to move in
a dugout canoe for use in our research.

That canoe ferried people and possessions
to our camp on the lake’s western shore.
Jan. 8th: At the Equator, dawn comes just
before 6 a.m. and night falls shortly after
6 p.m. We awakened at first light, not to
alarm clocks but to birds, howler
monkeys and the sound of breakfast
being fixed in the camp kitchen.

Work began right after breakfast.

The expedition leader. Dr. John
Jahoda (Bridgewater College,

Mass.), is doing an ongoing survey
of the black caiman population in
Zancudo Cocha. The black caiman,
Melanosuchus niger (family
Alligatoridae), was once abundant
in Amazonia but because of its
marketable hide has been hunted to
the point of extinction throughout
most of the Amazon Basin. Today
it is listed as an endangered species.

In the first research trip to Zancudo
Cocha in 1986, Dr. Jahoda found
evidence to suggest that the caiman

population there was a healthy one, and his
goal on this trip was to collect data on
population size, habitat utilization patterns
and distribution.

Dr. George Milne (Pfizer Inc., Conn.),
assisted by Carol and Adam Milne,
collected temperature and water chemistry
data and took sediment cores to learn more
about the limnology and geological history
of the lake.

I was in charge of plankton collection.
The samples, to be sent to the Smithsonian
Environmental Research Center (Md.) for
study, may provide an index of the produc-
tivity of the lake.

Other work included documentation of
the botany of the area by high school
teacher Juan Sanchez, and a faunal study —
primarily amphibians and reptiles — by our
expedition medic, Jeff Corwin.

Jan. 9th: Dr. Jahoda and Meliton
Rivadeniera, a crew member who proved
himself to be a world-class caiman-catcher,
brought in 23 animals ranging in size from
0.5 to 1.5 meters (1.5 to 5 feet). The
capturing is done at night when the
animals’ eyes can be spotted as they reflect
the men’s flashlights. The animals woke us
with a chorus of squeaks, grunts and
splashing sounds from where they were
tethered along the bank. Dr. Jahoda and his
assistants measured and weighed the
animals and painted bright yellow identifi-
cation numbers on their heads. All were
then freed at the site of capture.

Jan. 10th: I collected plankton at the first
four stations and preserved the samples for
later study. Sampling at the remaining
eight stations was postponed until the fol-
lowing day, due to the unexpected arrival
of 27 Indians from homes along the Rio
Aguarico. They were interested in meeting
us, and many were hired to help carry our
gear out of the jungle at the end of the stay.
No complaints from us!

Jan. 11th: Dr. Jahoda took different
people with him on each night’s caiman

Jill Cadwallader with a Van Dorn water sampler
used for collecting plankton— free-floating micro-
scopic plants and animals.

hunt. This was my turn to record data on
captures and sightings. At the stem of the
canoe, Antonio Llori paddled silently along
the entire 8.8 km (5.5 mi.) shoreline. The
night was a warm 24° C (75° F). Stars were
bright, with the Southern Cross overhead.
Hoatzins, primitive birds whose young have
two claws at the bend of the wing,
squawked and flapped noisily through the
palms as we passed their loosely
constructed stick nests, and an anhinga flew
out over our heads and dove into the water
behind the canoe. Six caiman were caught,
one in a dramatic one-handed grab, and a
number of previous captures were resighted
before we returned to camp at 2 a.m.

Jan. 13th: An early morning bird-watching
trip turned up more hoatzins, scarlet
macaws, various parrots, an Amazon
kingfisher, and yellow-rumped caciques
circling their pouch-like nests. Some of the
group went fishing and caught enough
pirana for an excellent dinner. Later,
Antonio led a hike along an almost invisible
trail behind camp, where we sampled the
refreshing liquid from pods of a Chambira
palm, watched leaf-cutter ants
carry leaf fragments twice their
size to an underground nest, and
learned how a jungle tree is trans-
formed into a dugout canoe.

Jan. 14th: The last full day in
camp. The dry season took an
intermission, and it rained hard
from dusk to dawn.

Jan. 15th - 20th: The trip
upriver took three days, with
loaded canoes moving slowly
against a rain-swollen current. In
Quito with time to spare, we
became tourists for a day and
explored Indian markets in the
Andean Highlands.

continued on page 3

L. to r.: Antonio Llori, Juan Sanchez, John Jahoda, George
Milne and Meliton Rivadeneira with caiman about to be returned
to site of capture.

Cold-loving Soil Fungi

Exact identification of a species of fungus often can be made only
by careful observation of spores and sporangia. Shown in this
photomicrograph by Dr. Carreiro are the hyphae (H) and
asexual reproductive structures (sporangia) (A and B) of the
microfungus Mucor, growing on agar. Spores (S) develop within
sporangia (A) and are released when sporangia are broken (B).
Spores will then germinate and grow into branched hyphae that
absorb nutrients as they penetrate leaf litter and soil.

The Institute of Ecosystem Studies makes
postdoctoral appointments to train out-
standing young ecologists. They contribute
to the Institute’s program and work to
establish themselves in the scientific
community. Dr. Margaret M. Carreiro is
one of seven postdoctoral associates
currently doing research at IES.

The enrichment of soils through release of
nutrients from dead organic matter is a by-
product of the life processes of a host of
small plants, animals and microbes that
inhabit organic substrates such as soil, leaf
litter and wood. One particularly important
group of these decomposers is the fungi,
organisms that obtain nourishment by
secreting enzymes that break down organic
matter so that the nutrients released may be
absorbed. Decomposer fungi can be class-
ified into two broad categories based on
size: the larger mushrooms, puffballs and
bracket fungi; and the smaller microfungi.
It is the latter group of decomposers that
are the subject of a new study at IES.

Microscopic soil fungi are not seen easily,
and to be identified and studied must be
isolated and grown on agar plates contain-
ing soil. Most of the research with these
fungi has been done by incubating the
plates at 25° C (77° F), on the assumption
that few species of fungi are active in soils
at lower temperatures. As a Ph.D. candi-
date in botany at the University of Rhode
Island, Margaret Carreiro became
interested in determining which soil fungi
are present and active in colder soils,
especially because in this part of the
country the top layer of forest soils are at
or below a temperature of 10° C (50° F) for
five to six months each year.

She began by collecting soil samples,
plating them on agar, and incubating half

the plates at 0° C (32° F) and half
at 25° C. She found totally
different fungal types on the
plates incubated in the cold, and
almost immediately discovered
two new species and rediscovered
one that had not been found by
scientists for 100 years. She also
saw that most of the “cold-loving
fungi” had different decomposi-
tional abilities than those isolated
at 25° C; they belonged to fungal
groups noted for breaking down
chitin, the material of insect exo-
skeletons. This group cannot,
however, break down plant
cellulose, which can be decom-
posed by many species in the
other group of fungi.

The next step in her thesis work
was to use a microcosm approach
to learn more about how tempera-
ture controls not only the types of
fungi that can grow in forest soils
and leaf litter but also the activity
of these fungi. She half-filled
quart mason jars with chopped
deciduous leaves moistened with distilled
water, and inoculated them with soil
samples. She incubated the jars for two
years, four at 0° C, four at 10° C and four at
20° C (68° F), the maximum temperature
reached by soils 10 centimeters (4 inches)
below the surface in Rhode Island. She
then isolated the fungal species from each
jar and measured the dry weight of the
leaves to determine how much decom-
position had occurred. Once again she
found that the species isolated from the 0°
jars differed greatly from those in the 20°
jars. The fact that the weight loss at 0° was
45% of that at 20° also showed that there
can be substantial activity in soils at
freezing temperatures.

In November 1989, Dr. Carreiro
began postdoctoral research at
IES. She has isolated cold
fungi from soils in this area —
although no new species have
been discovered here yet — and is
interested in expanding her work
to include how stresses caused by
pollution affect the species com-
position and function of soil
fungal communities.

Acid rain and traffic exhaust
deposit chemicals and toxic
metals that build up in soils.

Dr. Carreiro is looking for
changes in the composition and
activities of soil fungi that might
be signs of stress resulting from a
polluted soil environment. For

this study, she has selected sampling
sites in New York City, in suburban
Westchester County, N.Y., and in rural
Litchfield, Conn. The sites were chosen
because their plant species and soil profiles
are similar, making the surrounding
environment the principal variable in the
experiment. Soil samples will be plated
and incubated as in Dr. Carreiro ’s earlier
research, and differences in numbers and
kinds of fungal species, and/or the appear-
ance of sterile forms, will be noted as
possible indicators of stress.

Readers interested in knowing more about
this subject will want to join Dr. Carreiro’ s
June 1 7th Sunday Ecology Program,
“Fungal Foray: There’s More To the Soil
Than You Think!”

Journal , from page 2

Results of the caiman study, including data
from the supporting studies of biological
and physical aspects of Zancudo Cocha,
will be submitted for publication. In
addition, we hope that knowledge of the
caiman population and the natural history
of the surrounding rainforest will
contribute to efforts to make that area a
nature preserve, safe from the development
that endangers so much of the world’s
tropical rainforests.

This trip was organized through Nuevo
Mundo Expeditions in Quito, Ecuador.

Warming ,from page 1

What are the big problems that research
should be done on?

(The big problem is) the use of non-
renewable resources by people. We are
responsible for the progressive toxification
of the Earth, for its poisoned forests
and waters.

Editor’ s Note:

Within days of Dr. Woodwell’s talk, the
eastern part of the United States experi-
enced record-breaking cold. Skeptical
remarks about global warming were
common.

An unusually cold period does not disprove
the theory of global warming, just as the
unusually hot and dry summer of 1988 did
not prove that the theory was true. The
theory of global warming is based on cli-
matic conditions averaged over time —
close to 1 30 years of data have been used
in the calculations — and over space— the
whole Earth. The eastern United States is
just one small part of the globe and makes
only a small contribution to the world’s
average temperature. In the same way, in
any one geographic area a gradual global
increase in temperature would not be
expected to have a noticeable effect on that
area’s short-term weather patterns.

EARTH DAY
April 22nd, 1990

Join us for walks and talks !

Details will be available shortly . . .

Winter Calendar

CONTINUING EDUCATION PROGRAM
A number of winter semester classes and
workshops in landscape design and gardening
begin in March and spring semester programs
begin in April. Stop by the Gifford House or call
the number below to get a copy of the Winter/
Spring catalogue.

Ecological Excursions . . . Sign up by February
22nd for the March 8th trip to The New York
Flower Show.

SUNDAY ECOLOGY PROGRAMS
Free public programs are offered on the first
and third Sunday of each month, except over
holiday weekends. Programs begin at 2 p.m. at
the Gifford House on Route 44 A. For walks,
dress according to the weather, with warm,
waterproof footwear. Call (914) 677-5359 to
confirm the day's topic:

Mar. 4: Ecology and Earth History in Our
Grandest Canyon, a slide presentation by
Dr. Alan Berkowitz.

Mar. 18: The Ecology of the Sugar Maple, a
walk by an IES Education Program staff member.
Apr. 1 : Interpreting the History of Hudson
Valley Woodlands, a walk led by
Dr. Charles Canham.

Apr. 15: Easter Weekend — no program

In case of inclement weather, call (914) 677-5358

after 1 p.m. to learn the status of the program.

IES SEMINARS

The Institute’s weekly program of scientific
seminars features presentations by visiting
scientists or Institute staff. All seminars are held
in the Plant Science Building on Fridays at 3:30
p.m. Admission is free.

Mar. 2: Forest Disturbance and Organic
Matter in Streams - or How the Chestnut
Blight Saved Coweeta, by Dr. Jackson
Webster, Virginia Polytechnic Institute and
State University.

Mar. 9: Ensemble Dynamics: Local
Extinction and Persistence of a Parasitoid
and Its Host, by Dr. Donald R. Strong, Florida
State University.

Mar. 16: Recent Ecological Society of America
Initiatives in Public Affairs, by Dr. Marjorie
Holland, Director, ESA Public Affairs Office.

Mar. 23: Cultural Practices and the Ecology of
Maize Insects, by Dr. David Andow,

Univ. of Minnesota.

Mar. 30: Topic: Lake Geochemistry, by
Dr. George Kling, Marine Biological Laboratory,
Woods Hole, Mass.

Apr. 6: Great Lakes Ecosystem, by
Dr. Jim Kitchell, University of Wisconsin.

Apr. 20: Ecology and Evolution of
Inducible Defenses, by Dr. Drew Harvell,
Cornell University.

GIFT SHOP

Senior Citizens Days: On Wednesdays senior
citizens receive a 10% discount on all purchases
(except sale items).

Welcome-to-Spring Week, March 17-25:

Daily specials.

Easter Sale, April 1-15: 10% discount on
all items.

Spring perennials, including divisions from the
IES Perennial Garden, available after April 15th.

ARBORETUM HOURS
(Winter Hours: October 1 - April 30;
closed on public holidays)

The Arboretum is open Monday through
Saturday, 9 a.m. to 4 p.m.; Sunday 1 - 4 p.m.

The Gift and Plant Shop is open Tuesday
through Saturday 1 1 a.m. to 4 p.m. and Sunday
1-4 p.m. (closed weekdays from 1-1:30 p.m.).
All visitors must get a free permit at the Gifford
House for access to the Arboretum. Permits are
available up to one hour before closing time.

MEMBERSHIP

Become a member of the Mary Flagler Cary
Arboretum. Benefits include a special member’s
rate for IES courses and excursions, a 10%
discount on purchases from the Gift Shop, free
subscriptions to the IES Newsletter and Garden
(the beautifully illustrated magazine for the
enterprising and inquisitive gardener), and
parking privileges and free admission to the Enid
A. Haupt Conservatory at The New York
Botanical Garden in the Bronx. Individual
membership is $30; family membership is $40.
For information on memberships, contact Janice
Claiborne at (914) 677-5343.

For more information, call (914) 677-5359 weekdays from 8:30 - 4:30

INSTITUTE OF
ECOSYSTEM STUDIES
The New York Botanical Garden
Mary Flagler Cary Arboretum
Box AB, Millbrook, New York 12545

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Volume 7, Number 1
January - February 1990

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