A GIS-BASED THEMATIC MAPPING METHOD TO USE IN ESTIMATING THE ANNUAL AMOUNT OF NON-POINT SOURCE POLLUTANTS USING PARTIALLY UPDATED LAND-COVER MAP

摘要

The present invention relates to a geographic information system (GIS)-based thematic mapping method for estimating annual non-point source pollutant loads through partial updating of a land cover map. The purpose of the present invention is to manufacture a thematic map for estimating non-point source pollutant loads using an annually partially updated land cover map, the thematic map which is capable of being utilized in extracting land area information per land category more accurately in a GIS environment in applying loading unit law of multiplying an area per a land cover land category by a loading unit per the land category to quantitatively estimate scales of pollutant loads generated and discharged from a non-point pollution source in total maximum daily loads (TMDL) of Ministry of Environment. A GIS-based thematic mapping method for estimating annual non-point source pollutant loads through partial updating of a land cover map according to an exemplary embodiment of the present invention includes: a step of collecting relevant spatial data required in partial updating of a land cover map; a step of unifying a coordinate system of the spatial data collected through registration and conversion of coordinates; a step of extracting, from continuous cadastral maps, a region-of-interest which is suspicious about correction of land cover boundaries or land category properties; a step of partially updating the land cover boundaries and the land category properties by overlapping various thematic maps with respect to the region-of-interest; an inspection step for checking and inspecting updating result accuracy of land cover information; and a step of reclassifying land category classification properties of the inspection-completed land cover map into a loading unit land category for estimating non-point source pollutant loads.