Constructed Wetlands: Case Studies

Wetlands are zones or areas that lie on a continuum between terrestrial and aquatic environments and demarcation of the boundaries oen is not dened. In general terms, wetland is land where water is the dominant factor determining the nature of soil development and the types of plant and animal communities living in the soil and on its surface and the water table is usually at or near the surface or the land is covered by shallowwater. It spans a continuum of environments where terrestrial and aquatic systems intergraded. Natural wetlands perform both functions, which are benecial for both human and wildlife. Cowardin et al. [16] suggested that wetlands must have one or more of the following attributes for classication purposes: (1) at least periodically, the land supports predominantly hydrophytes; (2) the substrate is predominantly undrained hydric soil; and (3) the substrate is nonsoil and is saturated with water or covered by shallow water at some time during the growing season of each year.