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Wenzhou is located in the southeast coast of China, from June to September, typhoon brought heavy rainfall, can easily lead to collapse, landslides, mudslides and other geological disasters, causing serious casualties and property losses to the local, to a certain extent, restricts the development of the local economy. Therefore, in order to the local geological disasters caused losses to a minimum, to carry out a risk assessment of geological disasters in the region is imminent. This study is based on ArcGIS technology, comprehensive statistical analysis of the Wenzhou landslide hazard survey data based on comprehensive consideration of the existing risk assessment model to establish the risk assessment formula, namely: risk = risk × vulnerability / anti- disaster preparedness and mitigation capabilities, select the the Wenzhou respective township as the basic evaluation unit. According to this formula, we use fuzzy comprehensive evaluation method and level of analysis, the first establishment of Wenzhou landslide hazard vulnerability assessment model, to select population density, agricultural population density, vulnerable proportion of the population, arable land density, road density, building density per unit area of ??industrial output and farmers' per capita annual income of eight evaluation factors, Wenzhou landslide disaster vulnerability evaluation. Secondly, according to the actual situation, select two evaluation factors of fiscal revenue and forecast monitoring point, the simple ability to prevent and mitigate evaluation model to evaluate the landslide disaster prevention and mitigation capabilities, Wenzhou. On this basis, we combine the existing landslide hazard evaluation, completed Wenzhou township landslide hazard risk assessment for the evaluation unit. Finally, we have been a heavy rainfall caused landslides disasters and their losses caused by Wenzhou landslide risk evaluation results validate. Through this risk assessment, we got Wenzhou vulnerability level of landslide hazard maps, disaster prevention and mitigation level maps and risk rating maps. The vulnerability level maps basically reflects the degree of vulnerability of Wenzhou City, the township population and material economy; ability to prevent and mitigate distribution reflects the difference of the township in response to landslide disasters; risk maps reflects the difference of the magnitude of the loss caused by the landslide hazard to the township. Verification of the results of risk assessment and found that the losses caused by the landslide hazard, 76.74% of the losses occurred in high-risk and high-risk nature of the township, so we think that the level of risk distribution is more reasonable and reliable results satisfactory.
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