Interior Wetlands Of The United States

Interior, freshwater wetlands of the United States include potholes, marshes, swamps, bogs, fens, and riparian wetlands. These wetlands are diverse in form and function and have unique properties that make them different from both terrestrial and aquatic ecosystems. The biological complexity and ecological functions of wetlands make these ecosystems among the most valuable and productive on earth (Mitsch and Gosselink 1986:11). For example, wetlands are valued for functions such as surface-water storage, groundwater recharge, removal and transformation of nutrients, and soil stabilization (Greeson, Clark, and Clark 1979; Smith et al., In Preparation). Wetlands also provide habitat for fish and wildlife, including a third of the nation's threatened and endangered species (National Research Council (NRC) 1992a:265). Despite their ecological importance, wetlands have been lost and degraded at alarming rates. An estimated 53 percent of the original 89.4 million ha of wetlands in the lower 48 States were lost by the mid-1970s (Dahl 1990), and losses continued at approximately 117,000 ha per year from the mid-1970s to the mid-1980s (Dahl and Johnson 1991). The national policy has changed gradually over the past 20 years from 'encouraging the draining and filling of 'worthless swampland' to recognizing the many benefits provided by wetlands and considering them a valuable national resource' (Ratti and Kadlec 1992:1).

The early 1990's marked an environmental watershed for our countly. Under two federal administrations significant environmental legislative, regulatOly and institutional changes took place which affected our Nation's wetland resources. Injust a few years, we have seen rapid evolution in the way in which we view wetlands with more emphasis on specific wetland types and the geographic provinces in which they occur. This Southern Appalachian Man and the Biosphere (SAMAB) conference on "Wetland Ecology, Management and Conservation" represents just one example of our desire to understand wetlands in non-coastal regions of the southern United States. The backdrop to this conference was one where the government, universities, and private sector have come together to create a broader and more sophisticated understanding of environmental stewardship for our water resources, especially wetlands. Although enforcement of environmental legislation by federal and state government agencies - limited by manpower shortages, budgetary constraints and undermined by weak enforcement - remains strong as measured by world standards; the realization that environmental degradation of wetlands is likely to get much worse necessitates a greater commitment and increased resource allocation for wetland protection and management. These contiIUled pressures on the wetland resource will create substantial opportunities for the application of environmentally-sound technologies and interdisciplinmy modeling teams to keep abreast of the factors influencing wetland integrity and function in the last half of the 1990's.