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Wetlands

 

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Overview
Heated controversy has surrounded attempts to preserve wetlands. For decades, many thought wetlands were mucky, mosquito-infested places and drained them to use as farmland, industrial sites, or residential areas. Fewer than half as many acres of wetlands remain in the continental United States compared with when the first European settlers arrived about 500 years ago. Now, wetlands are recognized as important wildlife refuges and water purification systems. Wetlands are areas that have standing water for at least part of the year. Marshes, swamps, tidal flats and associated pools, bayous, and bogs are the most common. Marshes are water-saturated, poorly drained areas with both aquatic and grass-like plants. Swamps, unlike marshes, have trees and bushes. Water flows into swamps and marshes from streams, or even an ocean. Bogs are waterlogged, spongy ground in former lakes now filled with living and dead mosses, which eventually become peat. Wetlands are important for many reasons. They support a large volume of plants, which in turn supply cover and food for animals. Wetlands retain water like a giant sponge - flowing water is slowed as it passes through and is absorbed by plants and soils. By soaking up the water, wetlands not only prevent floods but make water available during a drought. They also help reduce the threat of low salinities in coastal waters. Wetlands can also clean up contaminated water. Organisms and soils in a wetland act as a filter for fertilizers and other pollutants. Algae and bacteria break down mineral and organic matter, which can then be used as food for plant life. Some municipalities use wetlands as the final stage in treating waste from sewage treatment plants. Other communities are actually constructing wetlands for this purpose. However, wetlands can't perform miracles. They can be ruined by too much waste. Because the economic and health benefits of wetlands are now well known, Congress has passed several laws protecting them. However, in many areas developers want to build on the land, farmers want to cultivate it, and oil companies want to remove the oil under the ground. As long as our population keeps growing, the struggle over what will become of the wetlands will continue.

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