关键词: 土地沙漠化, 驱动因素, "一江两河"中部流域, 西藏

Abstract: In the research on the driving force of land use/cover change,the problem of mechanism and driving factor of sandy desertification change is a very important research point,and so far it has not been better resolved.Taking the middle reaches of Yarlung Zangbo River and its two tributaries in Xizang as the research region,this paper makes use of the correlative analysis method to study the quantitative relationship of sandy desertification change and many kinds of natural and human factors that may influence the sandy desertification change,among which the driving factors of sandy desertification change can be found.The correlative analysis data are obtained from sandy desertification land investigation during 1990's,social and economic statistic data from 1989 to 1997 and climatic data in the same time phase.The analysis results can be concluded that the recent change of sandy desertification in the research region from 1991 to 1997 is the result of mutual action of natural process and human process of sandy desertification.The influencing factors comprise climatic factors and social factors as well as economic factors,in which the natural driving factors are wind force and arid degree;the human driving factors are farmland area and livestock number.In all driving factors of sandy desertification change in the middle reaches of Yarlung Zangbo river and its two tributaries in Xizang from 1991 to 1997,the function of natural driving factors is more important,they play a leading role in the process of sandy desertification change.

Key words: sandy desertification, driving factor, the middle reaches of Yarlung Zangbo river and its two tributaries, Ti-bet