Extraction of land cover information of Karst based on landform

Landscape limited forms of land use and land use type influence the formation and evolution of the landscape .In view of that relationship , this paper proposes an object -oriented land use/land cover classification method.Taking Anshun City with diverse karst landform types as an example and using 2010 TM images as the basic data source , the authors divided the test data according to different scale response characteristics of different karst landforms combinations and with multi -scale segmentation technology .Using DEM data and the derivative features such as slope , relief amplitude , and surface incision and establishing membership functions determining the threshold, the authors extracted the karst landform information .Then, on the basis of landform types and according to the landuse characteristics of different landform types , the authors divided landuse types by using nearest neighbor analysis .Overall classification precision reached 87.35%.Finally, the distribution characteristics of landform and land cover were discussed on the basis of the classification results .The results show that the landform types in the study area are mainly peak cluster valley and peak cluster depression , with a few karst pimple plains and hoodoo basins .Land cover types are mainly shrubs and dry land , which account for 25.58%and 20. 74%of total area respectively .