The Distribution and Diversity of Landscape Patches in Different Lithology-Landform Types in Karst Mountainous Areas
岩溶山区不同岩性和地貌类型下景观斑块分布与多样性分析

Abiotic environmental spatial variations and various disturbances were main divers,which resulted in landscape heterogeneity.Spatial patterns of landscape elements were dominantly enslaved to landform characteristics and disturbances.The objective of this study was to use Landsat TM data at a spatial resolution of 30m,1:50 000 topographic map and 1:250 000 DEM in 2000 to determine the distribution of landscape patches and the relations among the distribution of landscape patches,lithologic types and landform types basing on patch distribution and diversity index across middle-low mountains,hills,basins and valleys from southwestern Guizhou province,China.The results indicated that in the study site,shrubbery land,sparse-forest land and moderate coverage grassland were dominant landscape types.They were obvious landscape matrixes,and controlled landscape patterns and their evolvements.Moreover,there was an evident difference of landscape patches in different lithology-landform areas.Paddy,dryland,sparse-forest land and sparsely covered grasslands are distributed primarily in intermontane basins and plateau surface of homogenous limestone,limestone/clastic rock alternations and limestone interbedded with clastic rock areas,and river valley zone,which are rich in water and heat and are located at north of the study area.Forestland and shrubbery land occurred mainly in shallow and moderate dissected low mountains.Sparsely covered grassland and shrubbery land were detected mainly on low,middle and high hills,which are dissected deeply or shallowly in homogenous dolomite areas.Seen from spatial patterns and assemblages of karst rock deserti-fication,soil erosion and forest degradation,lithology and landform played pronounced roles in controlling the processes of eco-environmental heterogeneity.