GIS支持下三峡库区秭归县滑坡灾害空间预测  

Landslide hazard spatial prediction in Zigui County of the Three Gorges Reservoir Area based on GIS

作　　者：彭令[1] 牛瑞卿[1] 陈丽霞[1] 

机构地区：[1]中国地质大学地球物理与空间信息学院,武汉430074

出　　处：《地理研究》2010年第10期1889-1898,共10页Geographical Research

基　　金：国家自然科学基金项目(40672205);国家高技术研究发展计划(2007AA12Z100);国土资源部三峡库区三期地质灾害防治重大科学研究项目(SXKY3-2-2)

摘　　要：基于GIS空间分析和统计模型相结合进行区域评价与空间预测是滑坡灾害研究的重要方向之一。以三峡库区秭归县为研究区,选择坡度、坡向、边坡结构、工程岩组、排水系统、土地利用和公路开挖作为评价因子。为提高模型的预测精度、可信度和推广能力,利用窗口采样规则降低训练样本之间的空间相关性。建立Logistic回归模型,对滑坡灾害与评价因子进行定量相关性分析。计算研究区滑坡灾害易发性指数,对其进行聚类分析,绘制滑坡易发性分区图,其中高、中易发区占整个研究区面积的38.9%,主要分布在人类工程活动频繁和靠近排水系统的区域。经过验证,该模型的预测精度达到77.57%。Landslide prediction is very important in disaster prevention and reduction procedures,and it is one of practical research fields to evaluate and predict landslide hazards using statistic analysis model and spatial analysis of GIS.The aim of this study is to analyze landslide susceptibility using Logistic regression model in Zigui County of the Three Gorges Reservoir Area.In this paper,seven evaluation factors are selected,i.e.topographic slope,topographic aspect,bed rock-slope relationship,lithology,land use and distance from road and drainage.In susceptibility mapping,the use of logistic regression is to find the best fitting function to describe the relationship between the presence or Absence of landslides（dependent variable） and a set of evaluation factors such as topographic slope and lithology.Here,an inventory map concerning 37 landslides was used to produce a variable,which takes a value of 1 for the presence and 0 for the Absence of slope failures.In order to improve the accuracy and credibility of the model prediction,methods to reduce spatial autocorrelation in a logistic regression framework are also discussed.An optimal sampling scheme that can eliminate spatial autocorrelation whilst maintaining enough samples to achieve the accuracy based on the model is developed.The model was tested by the overall model statistics,and the results indicate that the model fits the dataset.The effect of each parameter on landslide occurrence was assessed from the corresponding coefficient that appears in the logistic regression function.The interpretation of the coefficients showed that land use plays a major role in determining landslide occurrence and distribution,although field observations showed that engineering construction exerts great influence on slope stability.With the help of a predicted probability map,the study area was classified into four categories of landslide susceptibility： high,moderate,low and none.The moderate and high susceptibility zones make up 38.9% of the total study area.In compar

关 键 词：滑坡 空间预测 LOGISTIC回归 地理信息系统 三峡库区 

分 类 号：P208[天文地球—地图制图学与地理信息工程] P642.22[天文地球—测绘科学与技术]