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ENGLISH 101. ACADEMIC WRITING |
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Reproduced below is Dr. Elizabeth Gutchess' model of a draft research paper
for English 101 students, "Undeveloped Streamsides: Corridors of
Life." Dr E collected the arguments for streamside preservation under
headings: protection of wildlife corridors, promotion of species diversity,
cleansing of pollutants, and human greenspace. Dr G has added boldface labels in brackets to
reveal the essay structure. |
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Undeveloped
Streamsides: Corridors of Life [BACKGROUND
OR STATEMENT OF PROBLEM]
All too often, suburban developers ignore topography and
build over creeks and streams that wind through areas
undergoing suburban expansion. They resort to storm drains and
culverts in order to divert natural waterways and convert watersheds
into commercial and residential properties (McHugh). Not only does this
practice result in flooded basements and roads. The inevitable
elimination of the valuable sides of small streams robs the environment
of a rich natural resource. The green borders of natural waterways--from
the smallest streams to wide rivers--deserve the very apt metaphor Tim
Palmer bestows on America's rivers: "corridors of life." [INTRODUCTION] Of course, throughout human history, these were important
corridors for human life: for transportation, for instance, and
milling, and irrigation for farms. And, granted, there still are serious
reasons to develop the sides of some streams--for the prevention of
destructive flooding, for example, and for mosquito (and disease)
control, and to meet agricultural needs for access to water.
Furthermore, there are studies which show that stream side
corridors can actually harm the larger ecosystems through which they
run--by facilitating the advance of aggressive alien species or by
transmitting pests and diseases (Perault and Lomolino). [THESIS
STATEMENT] But
in spite of these hypothetical dangers, and whenever human needs can be
met in less intrusive ways than by destroying natural corridors, the preservation of streamsides should be a
priority, for at least four reasons, for every community. [BODY
1: CORRIDORS FOR WILDLIFE]
For
one thing, undeveloped
streamsides provide important corridors for wildlife. The
pre-colonial forest of the eastern United States was made up of large,
continuous tracts, unbroken by farm fields or towns. Native American
villages and agricultural clearings were not extensive enough to create
significant fragmentation of the forest ecosystem. But now, at the
beginning of the twenty-first century, this forest is extensively
fragmented, broken into discontinuous patches by cities, suburbs, and
farms. Since so much of the forest survives in isolated tracts (islands
in fact), corridors of woods and vegetation between these large forest
patches have become important to the survival of wildlife (Yahner 108). Wooded corridors beside streams
provide cover, food, and water for seasonal migrations as well as
regular ranging activity (Yahner
110). They also provide protection from the inevitable inbreeding
and the gradual extinction that would result from populations living in
isolated habitats (Yahner
109), and they increase "the likelihood of recolonization"
if a local extermination has already occurred (Henry et al).
[BODY
1: CORRIDORS FOR WILDLIFE]
Researchers at
the University of Tennessee, in fact, have recorded how corridors can
help large mammals survive in a landscape that is now fragmented. These
wildlife biologists studied the movements of the Louisiana black bear
between forest patches surrounded and isolated by farm fields (of
soybeans, corn, and cotton) but also linked by wooded corridors of
varying widths. Their findings include the following: ·
Sub-adult
bears used the corridors to disperse from their natal home range. ·
Bears
preferred corridors to agricultural fields when outside a forested
tract. ·
Corridors
allowed bears to move farther away from forested tracts.
·
Bear
movement between wooded patches connected by corridors was more frequent
than between patches that were not connected.
·
All
female bear movement between wooded patches was between patches
connected by corridors. (Henry
et al.)
[BODY
2: CORRIDORS FOR BIODIVERSITY] This movement of wildlife is related
to another benefit provided by stream side habitat and another good
reason for communities to preserve it--the
remarkable level of biological diversity supported by this ecosystem.
Streamside habitats have levels of bio-diversity which are among the
highest in the world (Nilsson,
Jansson and Zinko). Even in the Arctic, riparian areas are
considered 'hot spots' of species richness in an ecosystem relatively
poor in biological diversity (Gould). There are several reasons for this
diversity beside streams. The clearest is simply the gradient.
Gradients, steep or gradual, along stream banks, can bring together
vastly differing habitats. Cattails, for instance, emergents
rooted in the water itself might grow a couple of meters away from a
species like cinquefoil, which can tolerate almost desert-like dryness
and grow in parched, even destitute soils on the tops of stream banks (Sanders
97). But the diversity of plant life on stream banks is caused
not only by the proximity of extreme habitats but also by the variety
produced by transitions between them. Obviously, transitions (ecotones)
would occur between the hydric soils of a stream’s marshy edges and
the possibly xeric soils along dry ridges on top of its banks.
"Transitions between two different ecosystem (or vegetation) types
contain compositional and structural characteristics of both adjacent
habitats as well as distinctive microhabitats found only in the
intermediate ecotonal area" (Risser).
In short, plants abound beside streams and rivers. [BODY
2: CORRIDORS FOR BIODIVERSITY] Even the flooding which
occurs intermittently along stream banks promotes diversity. It does
this by "slowing competitive exclusion" (Pollock, Naiman, and
Hanley): The
presence of water on a land surface dramatically changes the physical
and chemical environment of soils. These changes have a tremendous
influence on the competitive abilities of plants. The presence of water
can create severe physiological stress on plants that are highly
competitive under drier conditions, thereby lowering competitive
abilities. Conversely, plants adapted to wetter conditions may be at a
competitive advantage during a flood, but less competitive when water
levels drop. Therefore, a flood can slow down rates of competitive
exclusion without directly destroying vegetation (Pollock,
Naiman, and Hanley). Of
course, sites that are continuously or severely flooded would promote
the competitive exclusion of certain species and consequently be
species-poor. [BODY
2: CORRIDORS FOR BIODIVERSITY] Streamside diversity can
also be increased when streams act as "pathways for the invasion of
exotic plants" (Risser).
The stream corridor opens a range of habitats for new species to enter
an entire region.2 Flooding plays its role here, too, because a flood will create
the condition of habitat disturbance "necessary for
colonizing" (Risser). [BODY
3: CORRIDORS FOR CLEANSING POLLUTION]
A third good reason to preserve streamsides is that their
vegetation provides a cleansing system for undesirable amounts of
agricultural run-off into streams.
Run-off from farmland contains fertilizer
components--nitrogen and phosphorous--which are detrimental to the
balance of life in streams, rivers, and lakes. When streamside plants
absorb these nutrients, however, the quality of water downstream is
protected (Nieriing
33). A 1984
study of a streamside forest has shown the capture of nitrogen and
phosphorous as these
chemicals moved from agricultural fields across the landscape and into
the streams. The strips of riparian forest released relatively small
amounts of the annual input of nitrogen and phosphorous. 60-75% of all
the nutrients captured occurred in the first approximately 20m of the
riparian forest ecotone" (Risser). [BODY
4: CORRIDORS FOR GREEN SPACE]
There's another reason to keep streamsides green: as
they wind their way through neighborhoods, yards, towns, and villages,
they can answer a basic human need for "small wildernesses" in
everyday life. As Wendell
Berry says, I would
argue that we do not need just the great public wildernesses, but
millions of small private or semiprivate ones.
Every farm should have one; wildernesses can occupy corners of
factory grounds and city lots--places where nature is given a free hand,
where no human work is done, where people go only as guests, . . . .
places we respect and leave alone, not because we understand well what
goes on there, but because we do not (689). [BODY
5: THE EXAMPLE OF DRYDEN LAKE CREEK]
There are communities fortunate or wise enough to have preserved their
watershed areas--their creeks and wetlands--in a relatively undeveloped
state. In 1990, for instance, residents of the Town of Dryden, New York,
agreed with members of their county’s Environmental Management Council
that "the principal value" of a particular site in their town
(Dryden Lake and its outlet, Dryden Lake Creek) lay in "its high
quality as a natural area" (Tompkins) and opted for its preservation.
Stretches of Dryden Lake Creek, protected from development by the
council’s resolution, exhibit many of the features of a biologically
diverse, species-rich ecosystem. Streambanks and marshes have acted as
corridors for wildlife, as havens for the area’s surviving native
plant species, as ribbons of natural history, and as pathways for the
natural world to enter the environs of neighborhood and village. [BODY
5: THE EXAMPLE OF DRYDEN LAKE CREEK]
My web site "Dryden
Lake Trail: Twelve Field Trips" shows some of this diverse
habitat. As early as March, skunk cabbage flowers start rising out of
half frozen water (actually melting it), and not long afterwards marsh
marigolds are growing in the stream itself, trillium in the higher
woods, and blue flag (wild iris) are growing on small silty islands in
the fast current, iris colonies that might have been cultivated by local
Cayugas, since Native Americans raised wild iris for its aromatic and
medicinal roots. Creepy looking hellebore with its long, tongue-like,
poisonous leaves, and starry-headed meadow rue, with its crowns of
exuberant white stamens, are also there. So are swamp roses and swamp
milkweed, new and old cattails, bedstraws, duckweed, and cress. A whole
different assortment of plants grow on the tops of the streambanks,
alongside the railroad tracks. These are species of dry and impoverished
soil, and most of them are also be alien, or introduced, species,
opportunistic weeds which traveled along the sides of roads, behind the
pioneers who had built them: wild carrots and daisies, the thistles,
teasels, and hawkweeds, butter-and-eggs, and St. Johnswort, mallows,
burdocks, wild parsnips, and clovers, yarrow and bouncing bet. At the
very top, growing out of the cinders themselves,
is a wild rose--cinquefoil--a true weed in its ability to
flourish even in soils poisoned by industry. As the summer advances,
back down at creekside, another raft of native plants hold their own in
their original habitats and special niches: jewelweed, Joe-Pye-weed,
boneset, and blue vervain, all growing on the same bank; here and there
a dash of the most brilliant red--a cardinal flower; whorled
loosestrife, turtlehead and great lobelia growing in the damp shade; bur
marigolds with their feet right in the water; and wild cucumber vines
and virgin’s bower draped over everything else. Then, as summer winds
down slowly, asters and goldenrod grow all over. [CONCLUSION]
In short, this is a corridor of so much life, that most people would
have to agree that streamsides should rarely, if ever, be developed. Works
Cited Berry,
Wendell. "Getting Along With Nature." A Forest of Voices: Gould,
William A. "Biodiversity of an Arctic Riparian Ecosystem." McHugh,
Paul. "The Secret
Lives of Creeks." San Francisco Chronicle Henry,
A.C., D.A. Hosack, C.W. Johnson, D. Rol, and G. Bentrup. Niering,
William A. Wetlands. New York: Alfred A. Knopf, 1985. Nilsson,
Christer, Roland Jansson, and Ursula Zinko. "Long-term Palmer,
Tim. America by Rivers.
Washington, D.C.: Island Press, 1996. Perault,
David R., and Mark V. Lomolino. "Corridors and Mammal Pollock,
Michael M., Robert J. Naiman, and Thomas A. Hanley. "Plant Risser,
Paul G. "The Status of the Science Examining Ecotones." Sanders,
Jack. Hedgemaids and Fairy Candles:
The Lives and Lore of Tompkins
County Environmental Management Council. "Resolution 7-90. Yahner,
Richard H. Eastern
Deciduous Forest: Ecology and Wildlife
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gutchess@englishare.net Academic writing home page Gary Gutchess © 2003 |
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