西藏沙漠化灾害现状及其驱动力研究

西藏自治区是我国沙漠化灾害问题较为严重的地区之一，有沙漠化灾害土地19．974万km^2占全区土地总面积的16．58％，包括重度、中度、轻度3级和流动沙（丘）地、半固定沙（丘）地、固定沙（丘）地、裸露沙砾地、半裸露沙砾地5类沙漠化灾害土地，其中以中度沙漠化灾害土地和裸露沙砾地类沙漠化灾害土地为最多。沙漠化灾害将使区内生态环境与生存条件恶化，破坏建设工程，直接影响农业生产，导致人民生活贫困，并构成严重的潜在压力，造成了巨大的经济损失，平均年经济损失高达34．5亿元。驱动力分析表明，西藏的土地沙漠化灾害是在近期“全球变化”背景下气候干暖化和人为的过度经济活动共同促成的。

Research on the status of sandy desertification disaster and its driving force in Xizang

Xizang(Tibet) is one of the regions in which there is serious sandy desertification disaster in China. There is 19.974 x 104km2 sandy desertified land, which takes 16.58% of the total land area of Xizang, classified as 3 classes and 5 types of sandy desertification lands. The 3 classes are severe degree, middle degree and slight degree, in which the area of middle degree is largest. The 5 types are drifting sand(dunes) land, semi-fixed sand(dunes) land, fixed sand(dunes) land, bare gravel land and semi-bare gravel land, in which the bare gravel land is the largest one. In Xizang the sandy desertification disaster has made serious damages, which include leading to the deterioration of eco-environment and living conditions, destroying construction projects and hindering the economic development, doing great damage to farming and production and living installations, and making great economic loss and serious potential pressure. It is estimated that the annual total economic loss made by sandy desertification disaster in Xizang is about 34.5 x 108 Yuan. According to the analysis, the sandy desertification disaster in Xizang originated from the comprehensive effect of natural and human factors.. The climatic change on the basis of global warming background and the intensified human activities are its main driving forces.