中国东部亚热带丘陵山区土地退化坡面分带性的成因

中国东部地区流水侵蚀所引起的土地退化具有明显的坡面分带性。以安徽绩溪、浙江兰溪和广东五华为典型区，从坡地地貌及其所引起破面侵蚀分带性入手，通过坡面不同部位地面物质及其理化性质、养分和水分状况以及植被、侵蚀地貌形态的分析，探讨土地退化坡面分带性的成因。

DOWNSLOPE VARIATION OF LAND DEGRADATION AND ITS CAUSE IN THE UNRECLAIMED HILL AND LOW MOUNTAIN REGIONS,EAST CHINA

Downslope variation of land degradation has been observed in the unreclaimed low mountain and hill regions of East China.In this paper three case study areas were chosen to represent two types of regions of Quaternary red clay and heavily weathered granite.In order to explore the genesis of downslope differentiation of land degradation variation of surface materials and their physical and chemical properties,nutrition and soil moisture as well as vegetation cover and erosion morphology in different parts of slope was analyzed,based on slope morphology and induced erosion zonation.It has been concluded that downslope differentiation of land degradation is formed through a chain of processes in which variation of slope morphology and induced zonation of soil erosion results in downslope differentiation of surface materials and their physical and chemical properties,nutrition and soil moisture,while the latter in turn causes downslope variation of vegetation cover and erosion morphology.