Spatial pattern of the fragile karst environment in southwest Guizhou province
黔西南脆弱喀斯特生态环境空间格局分析

The karst areas in Southwest China constitute one of four fragile eco zones in China Southwest Guizhou, characterized by typical karst landscape and environment, is one of the major regions for rehabilitation in West China For a long time, human activities have led to serious rock desertification, soil erosion and forest ecosystem degradation in the study region, and have exerted adverse effect on regional economic development and ecology This paper analyzes ecological degradation, its spatial pattern and the related driving factors in southwest Guizhou province Rock desertification and soil erosion are the most serious ecological problems in southwest Guizhou, closely related to forest and soil degradation The karst landform pattern generally controls the ecological pattern, while population pressure and the resulting unreasonable human activities serve as the most powerful driving forces for environmental degradation Consequently, the regional man land contradiction is responsible for the deterioration of karst environment, with man as the core of the contradiction The rehabilitation of the deteriorating environment consists of two aspects,i.e., stopping human destructive activities and carrying out improvement measures Based on GIS analysis, the degree of ecological fragility ( I ) is given according to the equation: I=I 1 + I 2 -I 3 where I 1 is the ratio of rock desertified area, I 2 the ratio of soil eroded area, and I 3 the forest coverage The study region is divided into four sub regions in terms of the value of I: one extremely fragile sub region ( I =64), one seriously fragile sub region ( I =51), and two moderately fragile sub regions ( I =27, 26, respectively) This provides a framework for management of regional ecology and environment in southwest Guizhou