RS和GIS支持下的我国农牧交错生态脆弱区LUCC研究——以宁夏盐池县为例

基于遥感（RS）和地理信息系统（GIS）相结合的技术方法，提取了宁夏盐池县1991—2000年10年间土地利用/覆被变化（LUCC）的空间位置、数量和类型，采用土地利用/覆被变化转移矩阵，研究分析了土地利用/覆被的变化过程、特点和驱动力.结果表明:1991—2000年盐池县耕地面积净减少39 853 hm2，林地和草地面积分别增加27 055和13 251 hm2，流动沙丘面积减少4 659 hm2.但草原退化严重，中高盖度草场占土地总面积比重由51.21%下降到17.29%，而低盖度草场和极低盖度草场占地比重分别由4.09%和9.34%增加到36.40%和12.91%.生态环境局部有所好转，但整体继续恶化，土地利用整体处于不稳定调整期.耕地面积减少和林草地面积增加主要是由于农业生产结构的调整和“三北”防护林工程及其他治沙工程的实施，而草原持续退化主要是不合理的人为活动和草原使用“责、权、利”不明确等因素共同造成的. 

LUCC in farming pasture ecotonal areas based on RS and GIS--A case study of Yanchi County in Ningxia

Based on the integrated techniques of Remote Sensing (RS) and Geographic Information System (GIS), this paper extracted the location, quantities and types of LUCC(land use and land cover change) of Yanchi County in Ningxia Hui Autonomous Region from 1991 to 2000, and applied conversion matrix model to further analyze the process, features and drives of LUCC in this area. The studying findings were as following: from 1991 to 2000, the farming land decreased by 39 853 hm2,the forest land and pasture increased by 27 055 hm2 and 13 251 hm2 respectively, and desert decreased by 4 659 hm2. The pasture degraded considerably, the proportion of the high and medium-covered pasture accounting for total land areas decreased from 51.21% to 17.29%. In contrast, the proportion of the lower-covered and the lowest covered pasture increased from 4.09% and 9.34% to 36.40% and 12.91% respectively. The ecological environment in the county improved partially, yet got worse wholly. The land use was in the unstable and adjusting stage. The decrease in farming land and the increase in forestry and grass land resulted from adjustment of agricultural structure and the implementation of Three North Shelter Belt and other anti-desertification projects, while the degradation of pasture resulted from unreasonable human being activities and pasture tenure.