基于环境要素编码的泥石流沟道危险度快速识别

Rapid Assessment of Debris Flow Gully Hazards Based on Environmental Factor Codes

泥石流沟道危险度识别是泥石流灾害防治的基础.关于泥石流沟道及其危险度的研究过去已有很多,但关于泥石流沟道防治对策的差异性研究尚不充分,对于类似的泥石流沟道可能导致的类似程度的泥石流危险度的研究更加缺乏.本文提出了基于环境要素编码的泥石流沟道危险度快速识别方法,将影响泥石流沟道危害程度的多个环境变量信息,通过编码形式赋予特定的泥石流沟道.选取灾害记录比较完备的沟道作为参照组,依据灾害记录将参照组中的沟道分为若干类别,其余沟道则可根据其编码与参照组沟道编码的相似性,快速确定其所属类别,预测其危险度.本文以太原市西山地区的泥石流沟道为例,初步探索了该方法的可行性,结果表明该方法具有一定的准确性,但由于参照组沟道较少且灾害的发生具有随机性,个别沟道预测结果与灾害记录存在差异,增加参照组沟道数量可以增加预测结果的可靠性.本文的研究成果对于全面快速地识别泥石流沟道特征、泥石流沟道危险度快速预测,进而采取针对性的防治措施具有参考价值.

Debris flow gully hazard assessment is very important for debris flow disaster prevention. A large number of studies have been carried out on debris flow gully hazard assessment, but differences in debris flow gully control measures are not thoroughly researched, and studies that debris flow gullies with similar environmental factors maybe have similar hazards are scarcer. A new approach for rapid assessment of debris flow gully hazards based on environmental factor codes was proposed. Multi-factor information that can affect debris flow gully hazards was given to certain debris flow gullies by codes. Gullies with complete disaster records were selected as reference groups, and these gullies were classified into several categories based on disaster records. Then categories and hazards of other gullies could be determined according to the similarity between gully codes in reference groups and gully codes out reference groups. The feasibility of this approach was discussed by applying it in hazard assessment of debris flow gullies in Xishan region of Taiyuan, Shanxi Province, China. Most results given by this approach are accurate, but there are small differences between the results and disaster records because gullies in reference groups are not enough and debris flow occurrences contain random factors. More gullies in reference groups can improve the reliability of this approach. This paper is worthwhile for rapid and comprehensive identification of debris flow gully features, rapid assessment of debris flow gully hazards and adoption of focused control measures.