Comparison of soil maps with different scales and details belonging to the same area

Two different soil maps prepared by different institutes at scales of 1:200 000 and 1:25 000 covering identical areas were compared to determine the accuracy of reconnaissance. These soil maps are widely used in land resources assessment studies in Turkey. For this purpose, the soil maps were digitised and performed a data set. Then the map layers were compared by using GIS technology in order to assess the soil properties and land characteristics. The reconnaissance soil map at the scale of 1:200 000 has the highest accuracy for the slope due to the fact that topographic maps have been used as basic maps for the field studies. The accuracy of other properties in descending order is as follows; slope > depth > salinity > texture > drainage > top soil texture. In addition, physiographic and topographic patterns of soils also affect the accuracy of maps. The reconnaissance soil map was found to be less accurate in flood plains where the slope does not affect other soil properties.