A spatially explicit assessment and analysis of water-eroded desertification and its combating in Yunnan Province, China

Abstract

In a study on water-eroded desertification in Yunnan Province, we used remote sensing and geographic information system (GIS) to determine the areas of water-eroded desertified land objectively, to analyze the spatial distribution and causes of desertification in association with the geologic background, and to propose the appropriate measures for prevention and control. We found that the area of water-eroded desertification in 2008 was 35,949.69 km², accounting for 9.39% of the total land area in Yunnan. The main reason of desertification is the combined impact of the development of geologic structures and specific lithology. Human factors exacerbate and sometimes induce the desertification. We recommend that the desertification prevention and control should focus on the desertification-prone areas, including the neighboring regions of active faults such as the Jinsha River–Hong River fault, Yuanmou–Luzhi River fault, Fuyuan–Mile fault, Wenshan–Malipo fault, Nanpan River fault, Xiao River fault, and Qujing–Zhaotong fault; the sedimentary and Quaternary regions covered by mudstone, clay stone, and carbonate rocks; and the neotectonic regions such as the fold-style uplift region in east Yunnan, the secondary uplift region in southeast Yunnan, and the large block-style uplift region in central Yunnan. The population pressure should be reduced and industrial activities such as construction and mining should be more strictly regulated to prevent human activities from exacerbating water-eroded desertification.

Keywords:

• water-eroded desertification
• remote sensing survey
• comprehensive geologic cause analysis
• prevention and control
• Yunnan