长江上游泥石流危险度区划研究

RESEARCH ON THE REGIONALIZATION OF DEBRIS FLOW DANGER DEGREE IN THE UPPER REACHES OF CHANGJIANG RIVER

长江上游资源丰富，人口众多，生态环境脆弱，泥石流活动强烈，为了长江上游的资源开发和经济建设，开展了泥石流危险度的区划工作。区划采用综合研究与重点研究相结合，区域总体研究与典型区研究相结合，因素分析与相关分析相结合，间接自然指标与直接自然指标相结合，以及自然危险度与经济发展程度相结合的方法，将长江上游划分为五级泥石流危险程度不同的类型区。

The upper reaches of Changjiang River, including the part above Yichang Municipality,Hubei Province,is located in 24°28' 35°50'N,90°30' 111°20'E.Its drainage area is 100.5×10￣4km￣2 (and full length of the trunk stream is 4 500km), and area accounts for 55.8% of thetotal drainage area of changjiang River. The population is 37.5%, grazing area 71.5%,farmland 38.0%, uncultivated land 60.2%, water area 25.7% and usable water energyresources 86.3% of the total drainage of changjiang River.