30a来粤北山区土地石漠化演变过程及其驱动力--以英德、阳山、乳源、连州四县(市)为例

A Study of Rock Desertification Processes and Their Driving Forces in Northern Part of Guangdong,China,from 1974 to 2004——A Case Study on Four Counties of Yingde,Yangshan,Ruyuan and Lianzhou

论文运用RS、GIS等方法,重建了30 a来粤北岩溶山区4县(市)土地石漠化的时空演变与分异格局。30 a来本区石漠化土地在时间上由初步逆转向加速逆转态势演变,在空间上由多成片分布、少零星分布向多零星分布、少成片分布的分异格局演变。对本区气候变化、人为活动及其与石漠化的关联度、因子分析结果表明,人为活动是石漠化发展、逆转的主要驱动力,气候变化是次要驱动力。石漠化驱动力的互动激发机制、耦合机制、干预机制和反馈机制共同驱动着本区土地石漠化时空演变过程。

The karst mountainous area in northern part of Guangdong Province is one of the important rocky desertification regions in southern China. Under influence of climatic changes and human activities, the rocky desertified lands experienced positive or negative phases in recent 50 years in north Guangdong. In this paper, based on the scape of rocky desertified land in the study area, using classification type and synthetical landremote sensing, mapping, GIS analysis and statistical analysis, we analyzed the dynamic changes of rocky desertified land in time and space and then reconstructed the developmental and evolutional process of rocky desertification from 1974 to 2004. We found rocky desertified land was initially reversed between the early 1970s and the late 1980s, and was duratively and acceleratively reversed between the late 1980s and the early 2000s. The analysis of the relationship between climatic changes, human activities and rocky desertification indicated that human activities are the main driving force to the development and reverse of rocky desertification, especially policy change has a leading effect, and its contribution rate is greater than the climatic force. Restricted by regional and complicated ecological process of rocky desertification, its dynamical mechanisms are complex, which are composed of interference driving forces, natural and human coupling driving factors, oriented influence policy and feedback between driving forces and rocky desertification.