自然科学版学报

为定量评估黄河下游中小型城市商丘市的洪涝灾害风险性，利用GIS技术，以栅格格网(500 m×500 m)为研究尺度，从承载体暴露性、防灾减灾能力、致灾因子危险性和孕灾环境敏感性4个角度选取14个评估因子，采用层次分析法和地理加权叠加法构建风险评估模型，综合评价其洪涝灾害风险情况。结果表明：造成洪涝灾害较严重的影响因子有夏季降水变率、河流密度、年均降水量、植被覆盖度和坡度，其中夏季降水变率的影响率高达15.77%;商丘市风险区自南向北呈现层次性分布特征，高风险区的面积占比高达14.5%,且高风险区沿河流走向分布；黄河故道的高风险区主要集中在梁园区，在民权县中部和虞城县西部零星分布着一些较高风险区。建议政府相关部门避免城镇过度开发，改善生态环境，做好防涝排涝，利用高新技术进行防灾预测，并推进水利工程建设。

To quantitatively evaluate the flood disaster risk of small and medium-sized cities in the lower reaches of the Yellow River-Shangqiu City, a risk assessment model using Analytic Hierarchy Process and Geographically Weighted Superposition Method was constructed. This model is based on GIS technology and the research scale is raster grid(500 m×500 m). The model selected 14 evaluation indicators from four perspectives: bearing body exposure, disaster prevention and mitigation capabilities, risk factors of disasters, and environmental sensitivity to disasters, which were used to comprehensively evaluate the risk of flood and waterlogging disasters. The results indicate that the major influencing factors causing flood disasters include summer precipitation variability, river density, annual rainfall, vegetation coverage, and slope. The influence rate of summer precipitation variability factor is as high as 15.77%. The risk area in Shangqiu City presents a layered distribution from south to north. The area with an impact value greater than 0.5 accounts for 66.1%, and the distribution of high-risk areas is similar to the direction of rivers. High risk areas of the Old Course of the Yellow River are mainly concentrated in the administrative planning of Liangyuan District, and scattered in the middle of Minquan County and the west of Yucheng County. The study suggests that relevant government departments should pay attention to the situation of excessive urban development, arrange flood prevention and drainage work reasonably, use high-tech to monitor water levels, and promote the construction of water conservancy information engineering.