喀斯特峰丛洼地土地利用演变及其土壤侵蚀效应

The land use change induced by unreasonable human activities may result in soil erosion and other negative ecological effects, and thus, to understand their coupling relations is of great significance. Taking a representative karst cluster-peak depression region of Shirenzhai ingreat significance. Taking a representative karst cluster-peak depression region of Shirenzhai in Puding of Guizhou, Southwest China as study area, and by using stable and radioactive isotopes tracing, this paper studied the land use change and its effects on soil erosion since the 1960s, and analyzed the coupling relationships between them, based on the "pattern-process-scale" and the "source and sink landscape" theories of landscape ecology and the location-weighted landscape contrast index (LCI). In the study area, an event of sloping field forest transformed into cultivated land was recorded at about 100 cm depth in soil profile, and subsequently, a large amount of eroded soil from the sloping field was precipitated on the depression. After the event, cultivation period came. The depression was cultivated with corn, rape, and soybean in rotation. This study provided a new perspective for optimizing the local land use structure and controlling the water and soil erosion in watershed.