Accuracy and congruency of three different digital land-use maps

For numerous model applications in the earth and environmental sciences, digital land-use data are indispensable as a source of information on the geographical distribution of the land-use/cover. Therefore, the land-use data sets ATKIS, CORINE Land Cover, and Landsat TM classifications are widely used in Germany. However, the users of these data mostly do not have information on their quality. In this study, the accuracy of the three above-mentioned digital land-use maps was evaluated a posteriori based on the results of a field inventory in two test areas with a total area of 17 km2. The results show that the overall accuracy of the land-use maps varies from 0.692 to 0.876. For the individual land-use classes, the user accuracy ranged from less than 0.001 to 0.991. In this paper, the positional congruency of the land-use class polygons among the three maps was also evaluated for a larger study region of 670 km2 in the state of Hessen (Germany). This region is a small structured landscape with a relatively high portion of fallow land. In the analysis, the following six land-use classes were considered: urban and traffic areas, forest, water, arable land, pastures and meadows, and fallow land (including other uses). The results showed that the congruency of the land-use classes forest and urban and traffic areas is higher than the congruency of the land-use classes of the open land (arable land, pastures and meadows, fallow).