LANDSCAPE PATTERN AND FRAGMENTATION IN DONGLINGSHAN MONTANE REGION

As a result of the disturbance associated with human activities, the zonal vegetation in Donglingshan montane region, Beijing,——warm temperate zone deciduous broad leaf forest——has been completely destroyed. Present vegetation consists of secondary vegetation and plantations. By examining vegetation maps, on a GIS platform, and utilizing a number of landscape pattern indices, the landscape pattern of the Donglingshan montane region was analyzed and the degree of fragmentation evaluated. Fragmentation was assessed through measures of patch area, perimeter, number of patches, fractal dimension and landscape diversity. Results showed that, forest and shrub types are the main components of the present vegetation in the montane region. The area of different landscape elements was very uneven, with most landscape types are dispersed among many small areas. The area, perimeter and number of patches of forest areas are smaller than those of shrublands, grasslands and farmlands, however the perimeter and patch densities are higher, indicating a higher degree of fragmentation of forest areas. A power law relationship was found among the mean patch areas and perimeters of all the landscape elements, with a fractal dimension of 1.30, indicating a low degree of patch perimeter complexity in the landscape. The Shannon index of landscape diversity were ranked as follows: element type area (2.262) element type perimeter (2.435) element type patch number (2.675), while all were smaller than that of equal probability (2.940). All of these results emphasize the highly fragmented condition of the forest landscape in this montane region.