中文摘要：

基于三期遥感影像图,通过土地利用相对变化率、净变化速度和土地利用程度综合指数等,分析渭干河流域近20年土地利用变化与利用程度的时空差异,并探讨土地利用程度与社会经济发展水平的关系。研究结论如下：（1）渭干河流域土地利用类型以草地和未利用地为主,其类型分布和面积变化存在时空差异。1990—2008年流域林地、水域、建设用地面积逐渐增加,草地、沼泽、未利用地有所减少,耕地面积先增后减,总体有所增加。（2）因未利用地面积比重较大,流域各县的土地利用程度普遍不高,但近年有明显提高。库车、沙雅、新和三县土地利用程度综合指数逐渐增长,拜城县先增后减,总体有所增长。流域各县的土地利用效益均逐年增长,后期增长率远大于前期。（3）土地利用程度与区域社会经济发展水平存在正相关,土地利用程度综合指数越高,单位面积GDP和空间城市化水平越高。未利用地面积比重的空间差异对各县市城市化水平之间的差异具有较大影响。（4）人类活动加剧、社会经济发展等因子是流域土地利用变化主要驱动因素。

英文摘要：

Based on the remote sensing images in 1990, 2000 and 2008, the relative rate and net speed of land use change were considered, and the integrated indexes of land use degree was also calculated. Spatial and temporal differences in the change and degree of land use in the Weigan River Basin in recent 20 years were analyzed, and the relation-ship between land use degree and level of social and economic development was discussed. The results showed that： （ 1 ） The main land use types in Weigan River Basin were grassland and unused land, the percentages of which were over 31% and 57 %, respectively. There were spatial and temporal differences in the size of area distribution and change of land use types. During 1990--2008, the overall trend of land use in this oasis presented an increase in forest land, wa- ter area and construction land, and a decrease in grassland, wetland and unused land, while cultivated land area in- creased first and then decrease, and the overall trend was increase. （2） Because of the larger proportion of unused land area, the integrated index of land use degree was lower, which showed a significant improvement in recent years. The land use degree index in the counties of Kuqa, Xayar, and Xinhe increased gradually, while that in Baicheng County re- duced after the first increase, and it increased in overall. The efficiency of land use in all counties in Weigan River Basin was growing year by year, and the growth rate in 2000--2008 was larger than that in 1990--2000. （3） There was a pos- itive correlation between the degree of land use and the level of social and economic development. The higher the land use degree index was, the higher the GDP per unit area and the index of spatial urbanization were. The spatial differ- ences in the proportion of unused land area had a greater effect on the differences in the level of urbanization. （4） These changes were tightly related to human-activity enhancements and social and economic development.