基于加权信息量方法的汕头市地质灾害易发性评价

Evaluation of geological hazard susceptibility in Shantou city based on weighted information method

地质灾害易发性评价对地质灾害防治工程、城乡土地规划等有重要指导作用,信息量模型是国内应用较多的一种地质灾害空间预测方法,很多专家和学者结合GIS技术应用信息量模型做了大量的研究工作。目前普遍应用的信息量模型是将评价单元的总信息量简化为各因素提供的信息量之和,很少有考虑地质灾害因子之间的权重大小关系,或只是做了简单的因素分析评估,往往会会影响地质灾害易发性评价结果的准确性。本文针对上述问题,以汕头市为研究对象,结合汕头市城市地质灾害实际分布情况,使用加权信息量模型开展了地质灾害易发性评价研究。该模型在计算评价单元的信息量时,充分考虑的评价因子的权重,而不是单因素信息量的简单叠加。论文选取坡度、坡向、地形起伏度、工程地质岩组、距构造距离、距水系距离等6个影响因素,利用“加权理想信息量模型”实现了对地质灾害易发性的等级划分,获得了汕头市地质灾害易发性的空间展布规律,为防灾减灾工作提供了决策依据。

The evaluation of geological disaster vulnerability plays an important role in guiding geological disaster prevention and control projects, urban and rural land planning, etc. The information model is a spatial prediction method of geological disasters that is widely used in China, and many experts and scholars have done a lot of research work combining GIS technology to apply the information model.At present, the commonly used information model is to simplify the total information of the evaluation unit into the sum of the information provided by various factors. It rarely considers the weight relationship between geological hazard factors, or simply makes factor analysis and evaluation, which will often affect the accuracy of the geological hazard vulnerability evaluation results.Aiming at the above problems, this paper takes Shantou City as the research object, and combines the actual distribution of urban geological disasters in Shantou City, and uses the weighted information model to carry out the research on the evaluation of the vulnerability of geological disasters.When calculating the information amount of the evaluation unit, the model fully considers the weight of the evaluation factors, rather than the simple superposition of single factor information amount.The paper selects 6 influencing factors, such as slope, aspect, topographic relief, engineering geological rock formation, distance from structure and distance from water system, and uses the "weighted ideal information model" to achieve the classification of geological disaster vulnerability, and obtains the spatial distribution law of geological disaster vulnerability in Shantou, which provides a decision-making basis for disaster prevention and reduction.