Wetlands: Here All Year? Background
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.