中文摘要：

基于降水、土壤、遥感与农户调研数据,利用遥感解译、面积加权重心、景观格局等方法,探讨科尔沁左翼后旗的土地利用/覆被格局及其变化。研究表明：土地利用/覆被空间分异明显,草地是最适宜的土地利用/覆被类型。相对优质的土壤被优先用于农牧业,符合当地半农半牧的生产方式;但47.70%的风沙土耕地说明土地已被过度开发利用为耕地。科尔沁左翼后旗土地利用/覆被变化剧烈,且以耕地与林地、草地的转换为主,阻止其转换是生态恢复的关键;变化耕地的土壤类型以风沙土和草甸土为主,风沙土变化耕地应当逐步退耕,草甸土变化耕地应注意地力的保持。基于研究结果,提出“退耕还林还草”在北方农牧交错区的实施应综合考虑对种植业与畜牧业的影响。

英文摘要：

The northern agro-pastoral ecotone is a fragile region in ecology and environment in China and land sandy desertification is the prominent eco-environment problem in this region. It is significant to explore the characteristics of land use/cover pattern and soil properties of changed land use/cover for ecological restoration in the agro-pastoral ecotone of northern China. By taking Horqin Left Rear Banner located in Inner Mongolia as a case study and using remote sensing data, precipitation data and soil data, land use/cover pattern and its changes were studied with methods of remote sensing imagery interpretation, area weighted gravity center model, and landscape indexes. Results were obtained as follows： （1） Land use/cover pattern had an obvious spatial differentiation and grassland was the optimum land use/cover type in Horqin Left Rear Banner. （2） Soils with high soil fertility and rich water resources were used as cultivated land and grassland in the first place. This was in accordance with the agriculture and animal husbandry production mode in the agro-pastoral ecotone of northern China; sandy soil is low in soil fertility, poor in water retention and has no soil structure; however, 47.70% of sandy soil was used as cultivated land, indicating that land was over reclaimed into cultivated land in the banner. （3） Land use/cover change was dramatic in this region, and the transformation between cultivated land and forest land/grassland was dominant in land use/cover change. Thus, it was crucial to prevent the transformation between cultivated land and forest land/grassland for ecological restoration in the agro-pastoral ecotone of northern China. The converted cultivated land was mostly distributed on sandy soil and meadow soil. Thus, farming fields converted from forests and grasslands on sandy soil must be stopped for the sake of ecological restoration. The converted cultivated land distributed on meadow soil should be fertilized in land use. Based on the results above, the implementation of ?