Management Measure for Wetlands - Glossary

Abiotic: Not biological; not involving or produced by organisms (Merriam-Webster, 1991).

Adsorption: The accumulation of substances at the interface between two phases; in water treatment, the interface is between the liquid and solid surfaces that are artificially provided (Peavy et al., 1985).

Biological assimilation: The conversion of nonliving substances into living protoplasm or cells by using energy to build up complex compounds of living matter from the simple nutritive compounds obtained from food (Barnhart, 1986).

Biotic: Caused or produced by living beings (Merriam-Webster, 1991).

Chelation: The process of binding and stabilizing metallic ions by means of an inert complex compound or ion in which a metallic atom or ion is bound at two or more points to a molecule or ion so as to form a ring; the increasing complex stability of coordination compounds caused by an increasing number of attachments (usually to a metal ion) (Barnhart, 1986; Snoeyink and Jenkins, 1980; Merriam-Webster, 1991).

Chemical decomposition: Separation into elements or simpler compounds; chemical breakdown (Merriam-Webster, 1991).

Complexation: The process by which one substance is converted to another substance in which the constituents are more intimately associated than in a simple mixture; chelation is one type of complexation (Merriam-Webster, 1991).

Connectedness: Having the property of being joined or linked together, as in aquatic or riparian habitats.

Constructed wetland: Engineered systems designed to simulate natural wetlands to exploit the water purification functional value for human use and benefits. Constructed wetlands consist of former upland environments that have been modified to create poorly drained soils and wetlands flora and fauna for the primary purpose of contaminant or pollutant removal from wastewaters or runoff. Constructed wetlands are essentially wastewater treatment systems and are designed and operated as such even though many systems do support other functional values (Hammer, 1992).

Denitrification: The biochemical reduction of nitrate or nitrite to gaseous nitrogen, either as molecular nitrogen or as an oxide of nitrogen.

Ecosystem: The complex of a community and its environment functioning as an ecological unit in nature; a basic functional unit of nature comprising both organisms and their nonliving environment, intimately linked by a variety of biological, chemical, and physical processes (Merriam-Webster, 1991; Barnhart, 1986).

Filtration: The process of being passed through a filter (as in the physical removal of impurities from water) or the condition of being filtered (Barnhart, 1986).

Habitat: The place where an organism naturally lives or grows.

Riparian area: Vegetated ecosystems along a waterbody through which energy, materials, and water pass. Riparian areas characteristically have a high water table and are subject to periodic flooding and influence from the adjacent waterbody. These systems encompass wetlands, uplands, or some combination of these two land forms; they do not in all cases have all of the characteristics necessary for them to be classified as wetlands (Mitsch and Gosselink, 1986; Lowrance et al., 1988).

Sedimentation: The formation of earth, stones, and other matter deposited by water, wind, or ice (Barnhart, 1986).

Species diversity: The variations between groups of related organisms that have certain characteristics in common (Barnhart, 1986; Merriam-Webster, 1991).

Upland: Ground elevated above the lowlands along rivers or between hills (Merriam-Webster, 1991).

Vegetated buffer: Strips of vegetation separating a waterbody from a land use that could act as a nonpoint pollution source. Vegetated buffers (or simply buffers) are variable in width and can range in function from vegetated filter strips to wetlands or riparian areas.

Vegetated filter strip: Created areas of vegetation designed to remove sediment and other pollutants from surface water runoff by filtration, deposition, infiltration, adsorption, decomposition, and volatilization. A vegetated filter strip is an area that maintains soil aeration as opposed to a wetland, which at times exhibits anaerobic soil conditions (Dillaha et al., 1989a).

Vegetated treatment system: A system that consists of a vegetated filter strip, a constructed wetland, or a combination of both.

Wetlands: Those areas that are inundated or saturated by surface water or ground water at a frequency and duration to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions; wetlands generally include swamps, marshes, bogs, and similar areas. (This definition is consistent with the Federal definition at 40 CFR 230.3, promulgated December 24, 1980. As amendments are made to the wetland definition, they will be considered applicable to this guidance.)

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