基于 RS 和GIS 的县域洪涝灾害风险评估

洪涝灾害风险评价是研究洪涝灾害的重要手段之一, 评价结果可为区域洪涝灾害监督预测、防洪减灾措施的制定与规划提供依据。以河北武安市为研究区域, 以自然灾害风险系统理论为基础, 考虑当地实际情况, 从洪涝灾害的致灾危险性、灾害敏感性以及防减灾能力三个方面出发, 选取降水、地形等自然因素和人口密度、经济投入水平等社会经济要素共 9 个评价指标, 采用 G IS 空间分析叠加功能、加权综合评价法等方法, 得出洪涝灾害风险评价结果。结果表明: 武安市洪涝灾害风险分布整体呈现由中部、西南部高风险区向四周逐渐递减的特点, 具体表现为河谷风险等级突出, 洺河沿岸地区的风险要高于其他地区; 平原风险等级明显, 平原区由于易出现洪水汇入, 且敏感性强的特点, 易出现洪涝灾害; 农耕区域的风险等级要高于林草区域。通过历史灾情数据对评价结果进行验证, 本文提出的武安市洪涝灾害评估结果与实际情况一致性较高。 Flood risk assessment is one of the important means to study flood disasters and can provide a basis for the planning of reg ional flood disaster monitoring and prediction, flood control and disaster mitigation measures. In this study, Wu' an City of Hebei P rovince was taken as study area, based on the theory of disaster risk system and the local actual situation, hazard, sensitivity , and prevention capability ability o f flood disaster were selected as assessment aspects. There were nine evaluation indicators of social economic factors such as population density and economic level. The GIS weighted comprehensive evaluation method and spatial analysis super position functions were used to obtain flood risk assessment results. The results indicated that the overall risk distribution o f flood disaster s in W ucan City was characterized by the gradual decline of the high2risk areas in the central and southwestern areas. Specifically, t he river valley had a high2r isk level, and the risk along the Ming River w as higher than other areas. The risk level of the plain was obvious, and the sensitivity was strong; the risk level o f farming area was higher than that in the forest and gr ass area. Through the historical disaster data to verify the evaluation results, the Wu' an flood disaster assessment results presented in this paper are consistent with the actual situation. 国家自然科学基金( 41771204)