| Abstract |
The report describes a portion of a large regional project undertaken by the Environmental Protection Agency (EPA) and water quality authorities in the States of Montana, Idaho, and Washington to identify and analyze factors which are affecting water quality in the Lake Pend Oreille hydrologic system. To achieve this directive in Montana, a spatial database is being constructed which will contain satellite derived land cover, photo-interpreted macrophyte locations, and data from other sources for climate, topography, hydrography, and soils. The database will be used by EPA Environmental Monitoring Systems Laboratory-Las Vegas to demonstrate the utility of a watershed scale information management system. The information management system is geared toward nonpoint pollution modeling and will evolve into a decision support mechanism capable of assessing the suitability and feasibility of various management scenarios (James and Hewitt, 1990). The data layers focus on the elements required for nonpoint source pollution modeling in which derivation of factors for soil erodability, rainfall, topographic slope-length, and vegetation management are generated for the watershed. The vegetation management factor will be partly based on land cover derived from Landsat Thematic Mapper satellite imagery. Vegetative management factors combine vegetative cover and soil surface conditions into one numerical factor. The report addresses only the generation of land cover for the Blackfoot River Watershed through quantitative remote sensing techniques. |
