辽宁省降雨型泥石流环境特征及分类预警

Environmental Characteristics and Classification Early Warning of Rain-type Debris Flow in Liaoning

基于辽宁省降雨型泥石流灾害特点,分析泥石流环境因子特征,运用地理探测器探究影响因子对泥石流空间分布的贡献权重,并探究不同环境背景下泥石流发生的前期有效降水量。结果表明:泥石流发生点主要位于海拔100~700 m、坡度大于10°的低山丘陵上,土壤砂性较高,多为棕壤土和棕壤性土,以旱地、林地为主;暴雨日数与土壤类型、植被类型、高程的交互作用对泥石流空间分布密度贡献值最高,泥石流风险预测要充分考虑多个因子共同作用的影响;诱发第一、二、三类泥石流的当日有效降雨量均值分别为59、90、110 mm,前3日累计有效降雨量均值分别为91、115、135 mm,前7日累计有效降雨量均值分别为90、120、152 mm。该研究成果可为灾害预警及防治工作提供理论参考。

Based on the characteristics of rain-type debris flow disaster in Liaoning,the characteristics of environmental factors of debris flow were analyzed,and the contribution weights of influencing factors to spatial distribution of debris flow were explored by using geographical detectors,and the effective precipitation in the early stage of debris flow occurred under different environmental backgrounds were explored.The results show that the debris flow sites are mainly located on the low hills with an elevation of 100~700 m and a slope greater than 10°,and the soil is sandy,mainly brown soil and browning soil,the sites are mainly dry land and forest land.The interaction of rainstorm days and soil type,vegetation type,elevation,has the highest contribution value to the spatial distribution density of debris flow.The average effective precipitation of the day induced the first,second and third types of debris flow were 59 mm,90 mm and 110 mm respectively,the average cumulative effective precipitation of the first three days were 91 mm,115 mm and 135 mm respectively,and the average cumulative effective precipitation of the first seven days were 90 mm,120 mm and 152 mm respectively.The research results provide theoretical reference for disaster warning and prevention.