ACCURACY ASSESSMENT OF LARGE-SCALE SOIL MAP PREPARED BY REMOTE SENSING APPROACH

Thematic accuracy of a soil map, an integral part of metadata standards, is the degree to which the attribute information in a map agrees with reality and its assessment provides an important information on the quality of soil maps. The present paper discusses the methodology for assessment of thematic accuracy and purity of large-scale soil map prepared using remote sensing approach with reference to detailed soil map (1:5000 scale) prepared based on intensive field traversing using cadastral map as a base. Seven soil properties namely soil depth, colour, texture, drainage, erosion, stoniness and calcareousness derived from soil map prepared using remote sensing technique have been used for assessing the thematic accuracy of soil map. The overall accuracy of large-scale soil map prepared by remote sensing technique has been found to be 59 to 73 per cent at 90 per cent probability. The methodology is very useful for assessing the soil map quality, particularly, in area-class thematic maps generation in large-scale land resource inventory programmes.