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National Wetlands Inventory History and Objectives |
During the past 28 years the Department of Wildlife and Fisheries Sciences at South Dakota State University (SDSU) has received research grants and contracts to identify, delineate, and classify wetlands, riparian zones, and uplands. Funding sources include the U.S. Fish and Wildlife Service’s (USFWS) National Wetlands Inventory (NWI) and the Wetlands Status and Trends programs, Ducks Unlimited, The Nature Conservancy, and a multitude of federal, state, and private sector entities. Initially, all wetlands were identified by photo-interpretation of high altitude color infra-red photo transparencies viewed through a stereoscope. Presently, most of the habitat identification is conducted using the computer and collateral digital data. This technology utilizes on-screen editing computer software to produce habitat databases with the aide of digital photography (DOQQ, NAIP, etc.), topographic maps (DRG), soil surveys (SSURGO), and digital elevation models (DEM). All photo-interpretable wetlands are classified using the Cowardin et al. “Classification of Wetlands and Deepwater Habitats of the United States.” Riparian areas are classified following the USFWS’s “A System for Mapping Riparian Areas in the Western United States.” Several different systems are used for classifying upland features. Prior to photo-interpretation and multiple quality control steps, the SDSU wetland team conducts extensive field verification throughout the project area.
The wetlands team has completed habitat mapping in 19 of the conterminous states and Alaska. The research team updated approximately 50% of the USFWS Wetlands Status and Trends plots, in various states, for the report “Status and Trends of Wetlands in the Conterminous United States, 1998-2004.”
Presently, the wetlands research team is identifying and delineating drained wetland basins in the historic prairie pothole region of southwestern Minnesota. Other research projects are being conducted in Utah, Montana, Mississippi, and Alabama.