Analysis on land-use pattern in Buerhatong River basin

The principles and the theory of landscape ecology were used to comprehensively study the landscape patterns of the headstream,the river valley of middle-down reaches and the Chaoyang branch of Buerhatong River.The results show that the forest land area is the biggest and occupies 64.9% of the total area,dry famland 19.7%,paddy field 3.6%,lawn 3.3%,town and residential area 2.3%，wetland(including river,reservoir and swamp) 0.7%.The number of dry farmland patches is the greatest,the area of forest land patches is the largest in average,and the variant coefficient of the patch areas is the biggest.Forested land occupies a most proportion in forest land.The proportion of forest land reduces obviously from the upper reaches to the middle-down area,among these changes the proportion of forested land area reduces by 30% rapidly,those of shrub,thin stocked land and other forest land increases by 8%.The farmland area in the middle-down reaches increases by 18% compared with that in upper reaches.The middle-down reaches is the most in the number of patches,the smallest in the mean patch size and the variant coefficient of patch size,the biggest in edge density,and relatively bigger in Shannons diversity index and Shannons evenness index.