How types of carbonate rock assemblages constrain the distribution of karst rocky desertified land in Guizhou Province, PR China: phenomena and mechanisms

Abstract In southwestern China karst rocky desertification (a process of land degradation involving serious soil erosion, extensive exposure of basement rocks, drastic decrease of soil productivity and the appearance of a desert‐like landscape) results from irrational land use on the fragile, thin karst soil. Soil particles in the Guizhou karst plateau were accumulated predominantly from residues left behind after the dissolution of carbonate rocks, and the thickness of the soil layer is related to the amount of argillaceous substances in the lost carbonate rock. This paper examines the spatial distribution of karst rocky desertified (KRD) land in Guizhou Province, and relates it to the different assemblages of basement carbonate rocks. Types of carbonate rock assemblages are discussed using a 1 : 500000 scale digital‐distribution map. Their distribution and sensitivity to erosion are analysed, demonstrating that the occurrence of KRD land is positively correlated to homogeneous carbonate rocks. Differences in physical and chemical properties of limestone and dolomite rocks lead to differences in dissolution, accumulation rate of soil particles and relief on the surface, and these factors influence land‐use potential. Copyright © 2004 John Wiley & Sons, Ltd.