The Analysis of Land Use and Landscape Pattern in Hydropower Cascade Exploitation Region of the Yellow River

Based on the remote sensing（RS） images of 1977,1996,2000,and 2006,the land use and landscape pattern changes in the areas of cascade hydropower station construction during the past 30 years in the upper reaches of the Yellow River had been analyzed with the geographic information system（GIS） technologies and ecological quantity analytical method.The results indicated that all land use types increased to some extent except watershed and unused land,and the areas of cultivated land increased most significantly.The change rates of land use were the highest between 1977 and 1996.The area of watershed decreased dramatically from 2000 to 2006,and the cause of decrease in watershed area was changing into cultivated and grass land.Both the patch number and fragmentation indices increased in the study area,and the landscape was being more fragmental over a period of 30 years.The heterogeneity in the area exhibited an ascending trend during 1977 to 1996,whereas it decreased from 1996 to 2006.