耦合地貌信息熵和斜坡单元物质响应率的泥石流危险性分析

以粤西高州马贵镇为研究靶区，通过地貌信息熵法分析流域地貌发育演化阶段和泥石流沟谷危险性；提出流域单元物质响应率的概念，并结合遥感影像解译得到的松散物源分布，探讨泥石流沟谷的物源敏感性；在此基础上，将地貌信息熵值和流域单元物质响应率进行耦合，开展地形和物源复合作用下的泥石流危险性评价研究。研究结果表明：研究区子流域地貌信息熵值的变化范围为0.1398~0.8787，沟谷地貌演化从幼年期至老年期均有分布，60.57%的研究区面积处于幼年期—壮年期，泥石流沟谷比较活跃、危险性大；研究区子流域单元物质响应率变化范围为0~0.1716，53.46%的沟谷流域对物源较敏感，面积约为85.667 km2；基于地貌信息熵值和流域单元物质响应率耦合的泥石流危险性评价结果表明，43.87%的泥石流沟谷处于中等及以上危险区域，泥石流危险性较大。对比分析发现评价结果和实际情况较为吻合，评价结果合理，优于上述两种方法单独评价的结果。该成果可以为马贵河流域泥石流危险区规划和防灾减灾提供参考。

Debris flow hazard assessment by coupling geomorphic information entropy and response rate of watershed unit material

Based on GIS, the method of geomorphology information entropy was used to analyze the developmental stages of the geomorphologic evolution and debris flow hazard degree. The concept of response rate of watershed unit material was proposed and the provenance sensitivity of debris flow gullies were explored combining the distribution of loose materials interpretated by remote sensing images. On these base, the values of geomorphology information entropy and response rates of watershed unit material were superimposed to conduct debris flow hazard assessment by coupling the conditions of geomorphology and loose materials. The results show that: the range of the value of geomorphic information entropy is between 0.1398 and 0.8787 in the study area, valley geomorphic evolution is distributed from childhood to old age, and 60.57% of the study area in its childhood to maturity stage and the debris flow valleys are active and dangerous; the range of response rate of watershed unit material is between 0 and 0.1716 in the study area, the high, less high and moderate degrees of provenance sensitive areas accounted for 53.46% of the total area and the area is approximately 85.667 km₂, the result of debris flow hazard assessment by coupling the geomorphology information entropy and response rates of watershed unit material indicates that more than 43.87% of the debris flow watersheds are located in moderate and above moderate hazard zones, where debris flow activity seems dangerous. It is found by comparative analysis that the results are consistent with the watershed actual situation which can be applied to the plan of debris flow hazard zones and provide reference for debris flow mitigation of Magui watershed.