Abstract: Mu Us Desert is one the most sensitive and vulnerable areas in China. Based on spatial analysis tool of GIS, this study performs a dynamic ecological vulnerability assessment of Wushen Banner in 1960s, 1978, 1988, 2000 and 2008 by using the ecological vulnerability evaluation model established though analytic hierarchy process. The conclusion is that the majority parts of Wushen Banner belongs to middle and low vulnerable area. The grassland ecological vulnerability experienced decrease, increase and decrease in recent 50 years, and the grassland ecological vulnerability of southern Wushen Banner is higher than the northern area. The changing process is caused by two reasons. One is that Wushen Banner ecosystem locates in the semiarid and heavy sand-wind area, another is the ecological interferences which include both natural and social aspects, especially by fluctuation of aridity, population growth and extensive ranching. Finally, the authors give suggestions about how to protect and utilize the grassland resource based on the evaluation result.

Key words: Wushen Banner, grassland ecosystem, vulnerability

摘要： 选择位于毛乌素沙地腹地的乌审旗作为研究区, 基于1960年代, 1978, 1988, 2000和2008年土地覆被数据, 借助GIS空间分析技术, 通过建立“敏感性-弹性-压力”生态脆弱性评价模型, 对研究区近半个世纪的草地生态脆弱性进行动态评价。结果表明: 乌审旗草地生态系统大部分属于中、低度脆弱区。50年间, 草地生态脆弱性经历了持续减小、增大、再减小的变化过程, 在空间分布上呈现南高北低的格局。草地脆弱性的时空变化一方面与当地生态系统处于半干旱气候、风沙地貌等生境特点有关, 另一方面与生态系统受到的干扰(包括自然和社会两方面)直接相关, 尤其是干燥度的波动、人口的增加、放牧规模的扩大以及放牧模式的改变等。最后, 基于草地生态脆弱性评价结果, 提出生态安全建设时在草地保护和利用方面的对策建议。

关键词: 乌审旗, 草地生态系统, 脆弱性