Categorization of karst landform on the basis of landform factor eigenvalue

In this paper, digital elevation model （DEM） is used to divide sub-basin and seven landform factors that affect the karst geomorphology, including elevation, slope, relief amplitude, surface roughness, surface incision and elevation variance coefficient as well as topographic index, are extracted. A method of terrain factor eigenvalue is proposed for categorizing karst landform. Houzhai basin was chosen to be divided into eighteen basins. Sixteen basins were selected to distinguish their landform type, and the other two are chosen for the method verification. The statistical analysis of a single landform factor and fuzzy cluster analysis of multi-landform factors of the landform factor eigenvalue are carried out in order to determine the threshold of the peak cluster and peak forest landform in the Houzhai basin. The results demonstrate that the method based on landform factor eigenvalue is suitable for quantitative categorization of karst basin landform.