基于信息量法的湖北省秭归县滑坡易发性评价

Evaluation of Landslide Susceptibility in Zigui County,Hubei Province Based on Information Quantity Method

本文以湖北省秭归县为研究区,选取高程、水系距离、道路距离、岩土体类型、坡向、坡度、土地覆盖类型、年降雨量等8个评价因子开展滑坡易发性评价工作,依据ArcGIS软件数据分析工具完成各评价因子相关性分析。对评价因子相关性值|r|>0.1的高程、坡向因子剔除,计算各因子信息量值。利用信息量模型进行滑坡易发性评价,将研究区划分为四个区域:(1)极高易发区,面积140.0864 km^(2),占研究区总面积6.18%,主要分布在长江及支流沿岸;(2)高易发区,面积1002.445 km^(2),占研究区总面积44.23%,主要呈带状分布在极高易发区两侧,部分位于两河口镇、磨坪乡周边区域;(3)中易发区,面积833.8711 km^(2),占研究区总面积36.79%,呈带状分布在极高易发区两侧,零散分布;(4)低易发区,面积290.2564 km^(2),占研究区总面积12.80%,多分布在高山人稀区域。本文研究结果能够较好地反映研究区滑坡灾害分布规律,可为秭归县防灾减灾工作提供依据。

In this paper,Zigui County,Hubei Province is taken as the research area,and eight evaluation factors such as elevation,water system,road,rock and soil type,aspect,slope,land cover type and annual rainfall are selected to carry out landslide susceptibility evaluation,and the correlation analysis of each evaluation factor is completed using ArcGIS software data analysis tool.The elevation and aspect factors with correlation value of evaluation factors|r|>0.1 are eliminated,and the information value of each factor is calculated.The information model is used to evaluate the landslide susceptibility.The study area is divided into four regions:(1)Extremely high susceptibility area,with an area of 140.0864 km^(2),accounting for 6.18%of the total area of the study area,are mainly distributed along the banks of Yangtze River and its tributaries.(2)High-prone areas,with an area of 1002.445 km^(2),accounting for 44.23%,are mainly distributed on both sides of the extremely high-prone areas,and some are located in the surrounding areas of Lianghekou Town and Moping Township;(3)The medium-prone area,with an area of 833.8711 km^(2),accounting for 36.79%,is distributed in strips on both sides of the extremely high-prone area and is scattered.(4)Low-prone areas,with an area of 290.2564 km^(2),accounting for 12.80%of the total area,are mainly distributed in mountainous areas with sparse population.The results of this study are in good agreement with the actual situation in the study area,which can better reflect the distribution of landslide disasters in the study area and provide a basis for disaster prevention and mitigation in Zigui County.