ABSTRACT
Characterized by a shallow water table (Sharitz and Batzer 1999), wetlands are transitional landscapes between open water systems and terrestrial uplands. They provide many crucial ecosystem functions and values, such as flood control, groundwater recharge, sediment and pollutant retention/stabilization, nutrient removal/transformation, and fish and wildlife habitat and diversity (Mitsch and Gosselink 2000). Wetlands are prone to be filled in, drained, or ponded for a variety of human uses including stream channelization and maintenance, urban development, transportation improvement, or conversion to agricultural uses (Dodds 2002). To protect wetland resources, many laws and regulatory programs have been established. Among them, the Clean Water Act (CWA) Section 404 is the primary federal law aiming to maintain and restore the chemical, physical, and biological integrity of the wetlands in the United States. It authorizes U.S. federal agencies, mainly the U.S. Army Corps of Engineers, to issue permits for the discharge of dredged or fill material into the navigable waters at specific disposal sites, including wetlands (USACE: https://www. usace.army.mil/cw/cecwo/reg/sec404.htm). To comprehensively evaluate individual or cumulative impacts of human activities on existing wetlands, a regulatory permit assessment requires quickly retrievable environmental and socioeconomic data, and more importantly, a scientifically justifiable evaluation framework for analyzing those data. In recent decades, GIS techniques have been increasingly used to facilitate the data management and visualization in regulatory wetland assessments or permit reviews, aiming to improve the efficiency of the permit assessment process. A pilot decision supporting GIS for the permit analysis was developed in the early 1990s (Ji and Johnston 1994, 1995). The system was based on a widely used commercial GIS (Arc/Info, ESRI, Inc.), with customized user interfaces for data retrieval, visualization, and analysis. Other similar GIS-based technical tools were also developed, such as the Permit Application Management System (PAMS) for
evaluating and tracking the status of permit applications submitted for approval by the Connecticut Department of Environmental Protection, and ERATools for managing permit data and analyzing potential impacts of permitted activities by the Florida Department of Environmental Protection. However, while these GIS tools are powerful and useful in data management, visualization, and spatial analysis, they usually lack the decision rules or models that can link geospatial data manipulations to evaluating how vulnerable wetland functions and values would be under potential human impacts in the context of regulatory assessment. Thus, rule-based decision models need to be developed and incorporated with the GIS tools.
