Location determination of ecologically vulnerable regions in China

Ecologically vulnerable regions in China are not only the most serious areas of environmental degradation, but also the most poverty-stricken regions. However, these regions are still undefined. Three typical factors including land desertification, soil erosion and rocky desertification were selected to establish an evaluation model of eco-environmental sensitivity by using Remote Sensing (RS) and Geographic Information System (GIS) technology. We conducted a comprehensive research on eco-environmental sensitivity to reveal its spatial features in a quantitative way in China, and redefine the location of ecologically vulnerable regions integrated with the existing relevant government documents and the previous research. Results are demonstrated as follows: the extremely sensitive areas are distributed in northwestern, southwestern, southeastern parts of China and loess hilly regions; the highly sensitive areas are located in the Altai Mountains, the Tianshan Mountains, the southern part of Yinshan Mountains, the Horqin Sandy Land, the Hulun Buir Sandy Land, the western part of Chang Tang Plateau, the Hengduan Mountains and the hilly mountains regions in Southeast China. A total of 18 ecological vulnerable regions in China were defined, comprising a total area of 2.4 million km 2 . The name, type, area, spatial distribution and the main ecological problems of each region were characterized. The spatial distribution map of ecologically vulnerable regions in China can be used as a base map for the redline delimitation of national ecological protection.