Most wetland indicators can be identified and evaluated in the field or by referring to maps, GIS coverages, reports and photographs (aerial or ground). The table below lists the major indicators for each of the principle functions of wetlands.  Each indicator can be identified and evaluated using either field data or nonfield data.  Remember to refer to the Glossary for descriptions and illustrations of these indicators.

Function	Indicators
Ground Water Recharge and Discharge	Non-field Data     Hydrogeomorphic type     Inlet/outlet class     Presence of springs and seeps     Soil types     Surface water hydrologic connection     Underlying surficial geologic deposits     Water regime Field Data     Piezometer data     Relationship to regional potentiometric surface     Water chemistry     Microrelief of wetland surface     Relationship to steep slopes
Stormwater and Flood Control	Non-field Data     Hydrogeomorphic type     Inlet/outlet class     Degree of outlet restriction     Basin topographic gradient     Ratio of wetland area to watershed size     Adjacency to a water body or waterway Field Data     Wetland water regime     Surface water fluctuations     Stem density     Microrelief of wetland surface     Presence of organic material     Occurrence of down-cut stream channel     Ocurrence of ditched channels
Improved Water Quality Toxic Retention Nutrient Removal Transformation	Non-field Data     Wetland land use     Basin topographic gradient     Degree of outlet restriction     Topographic position in the watershed     Hydrogeomorphic type     Water regime     Inlet/outlet class     Stream sinuosity     Dominant vegetation type     Occurrence of overbank flooding     Percent of wetland edge bordering a sediment source     Occurrence of ditched channels     Hydric soil type Field Data     Frequency of overbank flooding     Microrelief of wetland surface     Distribution of vegetation     Occurrence of organic material
Sediment Stabilization and Retention	Non-field  Data     Hydrogeomorphic type     Frequency of overbank flooding     Overland flow potential from upland areas     Percent of wetland edge bordering a sediment source     Ratio of wetland area to watershed area Field Data     Evidence of sediment retention     Microrelief of wetland surface     Stem density
Aquatic Diversity and Habitat	Field Data     Hydrogeomorphic type     Association with open water     Water regime     Ratio of water and vegetation cover     Stream sinuosity     Dominant vegetation     Wetland class richness     Vegetative density     Wetland juxtoposition     Habitat for anadromous or catadromous fish     Habitat for aquatic species     Occurrence of debris dams in wetland or stream Non-Field Data     Wetland land use     Adjacent to undisturbed upland habitat     Adjacent to upland wildlife habitat     Buffer for a water body
Wildlife Diversity and Habitat	Non-field Data     Wetland - size, class richness, class rarity,         class edge complexity     Surrounding upland habitat     Wetland juxtoposition     Water regime     Wetland land use     Presence of seeps and springs     Vegetative interspersion     Presence of islands     Presence of rare, endangered or threatened species     Link to a significant habitat Field Data     Micorelief of wetland surface     Water chemistry     Interspersion of vegetation cover and open water

Sources:
A Method for the Assessment of Wetland Function, Fugro East, Inc., 1995, for Department of Natural Resources
Wetlands of Maryland, Tiner and Burke, 1995, for U.S. Fish & Wildlife Service and Maryland Department of the Environment
A Comprehensive Nontidal Wetland Watershed Management Plan: A Guide for Local Governments, Clearwater et al., 1998, for Maryland Department of the Environment
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