Analysis on Land Use Change and Driving Factors in Key Regions of Ecological Construction——A Case Study of Chaohe River Basin

Chaohe River basin,the important water source of the Miyun reservoir and a key area of ecological construction,was selected as the study area.The land use and land cover change from late 1980s to 2005 were analyzed based on the GIS.Thus,the land use change driving force index system was constructed,and the driving forces of the land use and land cover change were identified by using the principal component analysis.The influence of driving factors including policy,economic,population and technological progress on land use change in the basin was analyzed.The results showed that woodland was the major land use type in the basin,and the changes of woodland and grassland from the late 1980s to 2005were prominent.The area of woodland increased remarkably,while the area of grassland decreased largely.Policy was the dominant factor affecting land use change in this basin.