A
wetland is a transitional area between dry land and a body of water and is
wet for all or part of the year. Wetlands’ soil
is saturated and supports plants that are adapted to wet conditions.
Until recently, wetlands were seen as problems to be solved. People tried
to fill them with dirt or drain their water so they could be farmed or
developed. Now we know that wetlands provide many important benefits;
therefore, today there are laws to protect them.
There are
many different types of wetland habitats, and they are classified according
to the salinity
of their water; the duration of water coverage (i.e., all the time,
when the tide is in, or during the rainy part of the year); the vegetation
they support (grasses, shrubs, or trees); and their sources of water.
Sources of water include surface water and groundwater. Surface water
includes streams, rivers, ponds, lakes, bays, and oceans. Ground water
exists among pieces of soil, sand, and gravel; in cracks in bedrock;
and in porous rock such as limestone. Wetlands can be supplied by ground
water, and ground water levels can be recharged by wetlands.
Wetlands,
such as wet meadows, bogs, swamps, bald cypress-water tupelo tree
swamps, pocosins (a special type of shrub wetland), and saltwater and
freshwater
marshes, cover four percent of Virginia.
Wetlands
provide many benefits. They provide habitat for a wide variety of wildlife.
Wetlands filter
nutrient and sediment pollution out of rain runoff. They hold existing
soil in place to prevent erosion. Wetlands soak up water and moderate
water flow, thereby reducing flooding.
Next: Session 1
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