Potential rocky desertification in relation to topographic factors in Karst mountain areas

To explore distribution of potential rocky desertification and their relationship with topographic factors, the middle and lower reaches of the Houzhai subsurface stream in Puding County was chosen as a study area. With the aid of GIS software, the 2004 potential rocky desertification distribution map was studied to analyze quantitatively correlation of topographic factors, such as elevation, slope, exposure and position, with areas of rocky desertification. Results show that potential rocky desertification distributed unevenly, and strong correlation (P<0. 05 or P<0.01) between topographic factors and potential rocky desertification patches of various grades. With rising elevation, the areas of slightly and moderately potential rocky desertification were increasing in proportion, while the areas of zero and extreme slightly rocky desertification decreasing. With rising slope, the area of zero rocky desertification was decreased, while the areas of slighty, moderately and extreme severely potential rocky desertification were increasing. With exposure turning from shady to sunny, the areas of moderately and severely potential rocky desertification were increasing. The correlation between slope position and potential rocky desertification was much weaker.