Hydrology and Physiography of Groundwater and Wetland Habitats - Freshwater Ecology: Concepts and Environmental Applications - page 58

FIGURE 4.10 Peat moss removed from a wetland (photo courtesy of Loretta Johnson).

One of the problems with studying and managing wetlands is defining
them. Although distinct delineation is difficult between a wetland and a
very shallow pond, or a slow shallow side channel of a stream, the prob-
lem of finding a definition for wetland lies more in deciding what is a wet-
land versus what is terrestrial habitat. These definitions generally depend
on the plants that are present (often water-loving plants, called hydrophytes )
and soils with characteristics, related to constant inundation (hydric soils),
particularly anaerobic conditions..
What is legally considered a wetland has particular importance with
respect to the requirements for wetland preservation. Policymakers are re-
alizing the central importance of wetlands as wildlife habitat and key fea-
tures of ecosystem function. Pressure from environmentalists has been for
more inclusive definitions of wetlands. Agriculturists, developers, and oth-
ers want more freedom to develop and drain both seasonally wet regions
and permanent wetlands. Consequently, numerous definitions of wetlands
have been developed by scientists, policymakers, and others (Sidebar 4.2).
There is no single, indisputable, ecologically sound definition for wetlands
because wetland types are very diverse (Sharitz and Batzer, 1999).
In many areas of the world, wetlands have been drained, filled in, or
considered useless land. In the United States, 70% of the riparian (near
rivers) wetlands were lost between 1940 and 1980, and more than half of
the prairie potholes (shallow glacial depressions in the northern high
plains that form vital habitat for waterfowl) as well as the Florida Ever-