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在陕北地区1986—2008年土地利用/覆被数据库的基础上,分析其土地数量变化和转移矩阵,并从气候、人口和政策方面揭示土地利用/覆被变化的驱动力,得出如下结论:1)1986—1995年,陕北地区土地利用数量变化不大,发生土地转移的区域主要集中在陕北北部,年降水的增加趋势是导致沙地-低覆盖草地、低覆盖草地-中覆盖草地转移的主要原因,而人口快速增长则是草地-旱地转移的主要驱动因素;2)1995—2008年,陕北地区土地利用/覆被类型变化剧烈,有林地和中覆盖草地面积显著增加,旱地面积大幅减少.退耕还林生态补偿机制的实施,缓解了由于人均耕地面积减少而导致的人地矛盾加剧的问题,同时又通过退耕还林、退耕还草、封山育林、封禁还草等多种模式,直接导致了旱地-有林地、旱地-草地、疏林-有林地和沙地-草地的转移,与此同时,年降水的增加也有利于封山育林和封禁还草成果的巩固.退耕还林工程作为1995—2008年土地利用/覆被变化的主要驱动力,有效地促进了陕北地区植被的恢复.
Based on the land use / cover database of Northern Shaanxi Province from 1986 to 2008, this paper analyzes the change of land quantity and transfer matrix and reveals the driving force of land use / cover change from climate, population and policy, and draws the following conclusions : 1) In 1986-1995, the quantity of land use changed little in northern Shaanxi, and the area where land transfer took place mainly concentrated in the northern part of northern Shaanxi. The increasing trend of annual precipitation was that sandy land-low covered grassland and low-covered grassland-middle covered 2) From 1995 to 2008, the types of land use and land cover in northern Shaanxi changed drastically, and the area of grassland with forest land and middle mulching increased significantly. However, the rapid growth of population was the main driving force for grassland- The area of dry land has been greatly reduced. The implementation of the ecological compensation system for returning the grain plots to forestry has eased the problem of aggravating the human-land conflicts caused by the reduction of cultivated land per capita. At the same time, we have also adopted various measures such as returning farmland to forests, returning farmland to grassland, Mode, which directly led to the transfer of dry land-woodland, dry land-grassland, sparse forest-forested land and sandy land-grassland. At the same time, the increase of annual precipitation is also conducive to closing hillside afforestation Consolidate the results of returning farmland to forest and grassland banned works as 1995 - 2008 land use / cover change is the main driving force, effectively promoted the recovery of vegetation in Northern.