Evaluation of thematic map accuracy in a land-use and land-cover mapping program

he widespread use by governmental agencies and private firms of Geographic Information Systems (GIs) for planning, regulatory, or facilities management purposes has led to an increased demand for thematic maps depicting land use and land cover (LULC). Because of inadequate funding, time, or training, these maps are often produced with inadequate quantification and documentation of their thematic accuracy. The Southwest Florida Water Management District is currently in the process of developing Lu/LC maps as part of its GIs database development effort. Presented here is a description of automated sample generation methods developed at the District using GIs techniques, results of statistical evaluation of these sample data, and the field experiences and person-hour requirements associated with the accuracy assessment of the LULC data. The methodology presented here, though applied to LULC maps photo interpreted from color infrared photography, is equally applicable to many other types of thematic mapping.