Share on Facebook Share on Twitter Email
Answers.com

wetlands

 

Land, such as swamps, marshes, and bogs, normally saturated with water. Development may be prohibited because it could disturb the environment. The U.S. Army Corps of Engineers (COE) and the U.S. Environmental Protection Agency (EPA) have adopted a regulatory definition for administering the Section 404 permit program of the Clean Water Act (CWA) as follows: ‘those areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions.'

Search unanswered questions...
Enter a question here...
Search: All sources Community Q&A Reference topics

Land, such as a marsh or swamp, normally saturated with water. Often protected from development by environmental law.
Example: A typical coastal wetland .

Wetlands are any of an array of habitats—including marshes, bogs, swamps, estuaries, and prairie potholes—in which land is saturated or flooded for some part of the growing season. According to the U.S. Fish and Wildlife Service, wetlands contain water-loving plants (hydrophytes) and hydric soils. They serve many ecological and practical purposes. Wetlands provide habitat and breeding sites for fish, shellfish, birds, and other wildlife; help maintain biological diversity (biodiversity); reduce the effect of floods by diverting and storing floodwaters; provide protection from storm waves and erosion; recharge ground waters; and improve water quality by filtering out sediments, excess nutrients, and many chemical contaminants. Wetlands provide recreational, research, and aesthetic opportunities such as fishing, boating, hunting, and observing and studying wildlife.

Since 1780 human activity has destroyed more than half the wetlands of the United States, which now make up only 5 percent of the land surface of the contiguous forty-eight states, or 104 million acres. Nevertheless, they are extremely productive, exceeding even the best agricultural lands and rivaling rain forests in quantity and diversity of plant and animal life. More than half of the saltwater fish and shellfish harvested in the United States—and most of the freshwater sport fish—require wetlands for food, reproduction, or both. At least half of the waterfowl that nest in the contiguous states use the midwestern prairie potholes as breeding grounds. Wetland dependent animals include bald eagles, ospreys, beaver, otter, moose, and the Florida panther.

Few people recognized the value of wetlands until the 1970s. Before then, most people considered wetlands to be wastelands. In an effort to make them more productive—primarily through agriculture or development—people destroyed them by draining, ditching, diking, or filling. Early legislation, such as the Swamp Lands acts of 1849, 1850, and 1860, allowed fifteen states on the Mississippi River to "reclaim" wetlands for cultivation. By the mid-twentieth century, accumulating evidence, including U.S. Fish and Wildlife wetlands inventories in 1954 and 1973, made clear that destruction of wetlands was causing declines in fish and waterfowl. Federal, state, and local laws—notably the federal Clean Water Act of 1972 and amendments in 1977—attempted to regulate destruction.

Development, agriculture, and increasing pollution still threaten U.S. wetlands. One-third of wetland losses have occurred in midwestern farmbelt states. All but three states (Alaska, Hawaii, and New Hampshire) have lost more than 20 percent of their wetlands. Biologists and economists agree that preserving wetlands is less expensive than attempting to restore those that have been damaged, and experts still argue whether it is even possible to restore wetlands and how scientists might measure restoration. The economic and biological feasibility of restoration is debated each time a developer seeks permission to build on a wetland, thus destroying it, and offers (or is required) to attempt to rehabilitate a second site in return. Many biologists feel that because damaged sites cannot be returned to their previous states, it may not be acceptable to allow this tradeoff.

Bibliography

Council of Environmental Quality. Environmental Trends. Washington, D.C.: Executive Office of the President, 1989.

National Research Council. Restoration of Aquatic Ecosystems: Science, Technology, and Public Policy. Washington, D.C.: National Academy Press, 1992.

 
Columbia Encyclopedia: wetlands
Top
wetlands, low-lying ecosystem where the water table is always at or near the surface. It is divided into estuarine and freshwater systems, which may be further subdivided by soil type and plant life into bogs, swamps, and marshes. Because wetlands have poor drainage, the area is characterized by sluggish or standing water that can create an open-water habitat for wildlife. Wetlands help to regulate the water cycle, filter the water supply, prevent soil erosion, and absorb floodwaters. More significantly, however, wetlands serve as spawning and feeding grounds for nearly one third of the endangered animal and plant species in the United States, and their ecological value in most other countries is comparable.

Many wetlands were destroyed by urban growth and farming before their value was recognized. More than half of U.S. wetlands in the lower 48 states have been lost since colonial times. Federal wetlands policy today is based on the wetlands provisions (1987) of the Clean Water Act. The working concept is that of "no net loss," a concept that has been interpreted in various ways by each federal administration. Although the U.S. Fish and Wildlife Service has estimated that more than one million acres (about 400,000 hectares) of wetlands were lost in the decade from 1985 to 1995, this assessment was down from nearly 3 million acres (1.2 million hectares) lost in the previous decade, before the wetlands preservation policy was in force. As part of the "no net loss" policy, developers who fill wetlands may create new ones, but a 2001 National Academy of Sciences report found that new wetlands were not always created and when they were they were often of lesser value, both to the environment and to people, than the wetlands they replaced. The report recommended that replacement wetlands be designed to recreate the function of the developed wetlands.

Because of the restrictions wetlands protection can place on development and agriculture, it has become a political battleground between property rights activists and environmentalists. In 2001 the Supreme Court ruled that the Clean Water Act did not authorize federal regulation of so-called isolated wetlands (wetlands that do not abut navigable waters or their tributaries); as much as a fifth of the nation's wetlands are potentially affected by the ruling.


 
 

 

Copyrights:

Business Dictionary. Dictionary of Business Terms. Copyright © 2000 by Barron's Educational Series, Inc. All rights reserved.  Read more
Real Estate Dictionary. Dictionary of Real Estate Terms. Copyright © 2004 by Barron's Educational Series, Inc. All rights reserved.  Read more
US History Encyclopedia. © 2006 through a partnership of Answers Corporation. All rights reserved.  Read more
Columbia Encyclopedia. The Columbia Electronic Encyclopedia, Sixth Edition Copyright © 2003, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/ Read more