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CHANGING
ATTITUDES
From farmers
to power-brokers, now many people appreciate wetlands. Science has
led this attitude adjustment.
Since the mid
twentieth century, biologists, hydrologists, geologists, and other
scientists have been studying wetlands to understand how they function,
and what they contribute to ecosystems, and to human health and
economy.
For example,
wetlands act like giant sponges, absorbing water during floods and
storms. This water, instead of washing downstream and loading water
with sediment, instead slowly soaks into the ground to recharge
aquifers and other sources of ground water. As water collects in
wetlands, this ecosystem cleans the water. Sediments settle out
as the water slows; the soil particles bind with pollutants, and
some plants absorb the toxins.
Wetlands also
absorb nutrients and toxins that otherwise would wash into our lakes,
rivers, and coastal waters. Some communities use this natural cleansing
ability of wetlands to treat the waste water and sewage that we
produce.
Such treatment
occurs in urban areas of Pennsylvania and Wisconsin, plus smaller
communities such as Moscow, Idaho.
Wetlands also
provide many products and foods that we use.
Hunters flock
to wetlands each year to hunt ducks, geese, and other waterfowl.
Timber companies
harvest trees from the swamps and wet forests of the southeastern
United States.
In some wetlands,
dense layers of rich organic material form as vegetation dies and
is compressed. Called peat, this resource is mined to provide a
soil conditioner for gardens and to provide fuel.
Wetlands also
serve as nurseries, cafeterias, and homes for fish and other aquatic
species that we humans love to eat. Studies estimate that wetlands
provide habitat at some point for at least two-thirds of the fish
caught and sold in the United States. We also collect foods that
grow in wetlands, such as wild rice, blueberries, cranberries, mint,
and onions.
Economists
consider all of these uses when they estimate the value of wetlands.
One small Massachusetts wetland has been valued at $200,000; one
acre of Louisiana coastal wetland might generate $80,000 in fish
and other resources.
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