Abstract:

Water deficit is the primary natural limitation restricting grassland productivity in China. Drought risk assessment is the core component of risk management. In this paper， by collecting meteorological， soil， vegetation， landform and other data， an assessment model for grassland drought risk in China was constructed after an in-depth analysis of this data. The model established an evaluation index system for drought risk， determined the weight of each index by the entropy weight method， and assessed the level of hazard， degree of exposure， sensitivity， and vulnerability. Based on a GIS spatial analysis function， an assessment and a regionalization analysis of grassland drought risk were then conducted for China. It was found that the high and sub-high drought-risk areas for grassland in China are mainly located in Inner Mongolia， the Hexi Corridor， the Qaidam and Tarim Basins， the western Qinghai-Tibetan Plateau and Yunnan. The high and sub-high drought exposure areas are mainly located in Southwest China and South China. The high and sub-high sensitive areas are mainly located in the southeast of Inner Mongolia， Northeast China， the South and east slopes of the Qinghai-Tibetan Plateau， the northern margin of Tarim Basin and the Southwest of China. The high and sub-high vulnerability areas are mainly distributed in the central and eastern parts of Inner Mongolia， the Hexi Corridor in Gansu， Northern Xinjiang， most of the Qinghai-Tibetan Plateau， Yunnan and eastern Sichuan. The high and sub-high risk areas for grassland drought are mainly located in the northeast of Inner Mongolia， the west of Northeast China， the North of Ningxia， the north edge of Tarim Basin， the South of the Qinghai-Tibetan Plateau， the Yunnan-Guizhou Plateau， Henan and Shandong. These results provide a theoretical framework and an initial scientifically-based evaluation for susceptibility to drought of grassland in China.

Key words: Chinese grassland, drought risk, risk assessmentt