长江上游地区不同土地利用方式对山地灾害的敏感性分析--以金沙江一级支流小江流域为例

长江上游是我国山地灾害异常活跃区，其频繁活动与该区域特殊的自然条件和人类经济活动密切相关。从自然和人文交叉最密切的领域——土地利用及其变化入手，选择区内山地灾害频繁活动区——金沙江一级支流小江流域为典型研究区，通过定量分析不同坡度土地利用方式对山地灾害的综合敏感性，发现易致灾的土地利用方式依次为：道路建设用地和工矿用地、>15°的旱地、>15°低盖度草地和人工修建的蓄水区、城市建设用地、>8°的裸岩地、>25°的滩地、>35°的高盖度草地，并根据敏感值的大小进行了敏感性区划。研究成果对规划土地利用方式、布局水土保持工程等具有一定的参考意义。

MOUNTAIN HAZARDS INTEGRATED SENSTITVITY ON LAND USE OF THE UPPER REACHES OF YANGTZE RIVER--A CASE STUDY OF XIAOJIGANG RIVER BASIN

In China, the mountainous upper reaches of Yangtze River Basin is the densely distributed area of maintain hazards, and the most important sediment supply region resulting from their intensive occur- rence. For hazards mitigation, sediment control, soil and water conversation in this area, much research has been conducted on the influence of physical factors on the occurrence of mountain hazards, but relative- ly little attention has been paid to the study of the integrated and quantitative influences of physical and hu- man activities factors, especially the impact of human activities. Currently, as one of the important factors influencing the occurrence of mountain hazards, land use has been recognized as the joint core field of the mutual action of natural process and human activities, and it supplies a new method to study the relations between mountain hazards and their physical and man-made causes. In this paper, sensitivity coefficient and its quantitative calculative method were introduced on the basis of GIS and RS technologies, and the sensitivity value of different kinds of mountain hazards on land use was systematically calculated through a case of Xiaojiang Basin in the upper reach of the Yangtze River. From this research, the most vulnerable land use types to mountain hazards are built-up for mining, road and railway construction, dry land at the slope larger than 15 degree, low-cover (5%~20%) grassland and reservoir at the slope larger than 15 de- gree, urban land, barren land at the slope larger than 8 degree, high-cover (>50%) grassland at the slope larger than 35 degree. The insensitive land use are forest-land, farmland at the slope lower than 15 degree, brush and sparse wood land and high-cover (>50%) grass-land at the slope less than 25 degree.