ASK A SCIENTIST
Question: Are we losing our wetlands and how fast are we losing them?
Answer: The prevailing attitude of many people towards wetlands could be summed up as, 'Wetlands are disgusting, useless, wastelands; mosquito breeding sites full of dangerous creatures; and an obstacle to progress.' The result: more than half of the wetlands of the lower 48 States have been drained, filled, or paved over. An estimated 220 million acres of wetlands existed in colonial times. That number is now 105.5 million acres. From 1986 to 1997, 58,500 acres of wetlands were lost each year. The amount of wetlands suffering from degradation, or the loss of function, due to pollution, human and naturally caused erosion, and invasive species is extensive. In New York State, as of the mid-1990's, there were 1.2 million acres of wetlands with 75 percent of those located in the Adirondacks and the Western Lake plains. New York experienced a minuscule net gain of .007% of wetlands between the mid 80s and mid 90s. Essentially, while the rate of loss has declined, the United States of America is indeed losing its wetlands.
Defining wetlands, politically and scientifically, has been a problem. A wetland is 'wet' land, right? It can be tough to locate wetlands since wetlands are often dry during the year for various reasons. Three characteristics of wetlands - taken into account together - help to identify them. First, wetlands are indeed 'wet' for a significant portion of the year. Second, the length of time of saturation influences wetland soils, which are usually low in oxygen content and grey in color from reduced iron. Finally, the hydrology and soil of wetlands influences the growth of specific vegetation. Wetland plants, such as cattails, bulrushes, and bur reeds are particularly adapted to grow in saturated soils and are good indicators of the presence of wetlands. There are many types of wetlands, from small woodland vernal pools to bogs, marshes, and the vast Everglades. The minimum size of a wetland is still being wrangled over by policy makers, conservationists, and scientists though, arguably, all wetlands are important.
Why should we care about preserving wetlands as well as any land left as natural as possible?
Two words: ecosystem services. Natural land functions create and regulate the conditions that allow humans to live on Earth; our only home. Wetlands perform specific functions that are important for wildlife and people, including mitigating floods, improving water quality, and providing habitat to countless animal species. Various studies have shown that maintaining 5-15 percent of a watershed as wetlands reduces flood peaks by 50 to 60 percent. The Congaree Bottomland Hardwood Swamp in South Carolina removes enough pollutants from the watershed to equal that which would be removed by a $5 million treatment plant. Wetlands are important in the life cycle of 75 perccent of the fish and shellfish caught in the multi-billion dollar commercial fishing industry. We have a wonderful example of a beaver-created wetland at the Binghamton University Nature Preserve that stores, filters, and regulates the flow of a huge amount of water and adds to the diversity of wildlife found in the area. Covering only five percent of the land of the United States, wetlands have an almost inestimable value.
To learn more about wetlands visit http://www.dec.state.ny.us/website/dfwmr/habitat/fwwprog.htm or
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