摘要
Climate change has significantly increased the intensity and frequency of extreme weather events,posing significant challenges to the hydrological ecological security of rural settlements in mountainous areas.There is an urgent need for research that predicts the flood risk of mountainous villages under future climate scenarios.Taking the mountainous area of the Yongding River Watershed in Beijing as an example,this study uses CMIP6 data and the Delta statistical downscaling method to predict precipitation with return periods of 20-a,50-a,and 100-a under the SSP126,SSP245,and SSP585 scenarios at the end of this century.A two-dimensional hydrodynamic model combining SWMM and HEC-RAS has been employed to simulate the flood risks of the villages in the watershed.The results show that:1)overall flood risk is higher for the villages located downstream of the Qingshui River and at the outlet of the Yongding River Gorge,with significantly increased inundation area ratio,maximum inundation depth,and the number of villages affected;2)with the increase in radiative forcing values of the SSP pathways,the inundation area ratio increases by up to 8.22%by 2100,significantly increasing the flood control pressure on settlements in the future;3)the correlation results between village spatial characteristics and flood risks show that the inundation area ratio is significantly negatively correlated with average river width and river sinuosity,and significantly positively correlated with river gradient and floodway proximity;the maximum inundation depth is significantly negatively correlated with average river width and significantly positively correlated with floodway proximity.Finally,this research suggests that it is necessary to integrate various spatial elements and resources from upstream and downstream areas by prioritizing the strategy of key area flood control and sustainable development,to reduce the flood risk to mountainous settlements under future climate change.
气候变化导致极端气象事件的强度和频度显著提升,对大量山区乡村聚落的水文生态安全造成了较大挑战,因此亟需对未来气候情景下的山区村庄雨洪风险预测开展研究。本研究以北京市永定河流域的山区为例,利用CMIP6数据和Delta统计降尺度方法,对本世纪末SSP126、SSP245、SSP585情景下,重现期为20、50、100年的降雨事件进行预测,并采用SWMM耦合HEC-RAS二维水动力模型,对永定河河道两侧村庄聚落进行淹没模拟。研究结果发现:1)就总体洪涝风险而言,位于清水河下游、永定河峡谷出口段的村庄洪水风险偏高,并且在未来三种气候情景下,淹没面积占比、最大淹没深度,以及村庄淹没数量均显著增加;2)随着SSP路径的辐射强迫值增大,世纪末期淹没面积占比最高增加了8.22%,在未来气候条件下山地聚落的防洪压力显著增大;3)分析空间特征与聚落洪水灾害的相关性结果显示,聚落淹没面积占比与河道平均宽度、弯曲度呈显著负相关,与河道比降及聚落是否紧邻行洪沟呈显著正相关;最大淹没深度与河道平均宽度呈显著负相关,与是否紧邻行洪沟呈显著正相关。本文最后提出应对未来气候变化情景的“重点区域防洪+可持续开发”策略,建议整合上下游各类空间要素资源,以降低未来气候变化对山地聚落造成的雨洪风险。
出处
《景观设计学(中英文)》
2025年第6期94-108,共15页
Landscape Architecture Frontiers
基金
北京市属高校教师队伍建设支持计划优秀青年人才培育计划项目城市蓝绿景观对热岛效应的减缓机制及优化策略研究”(编号:BPHR202203082)
国家社会科学基金项目“新旧杂陈的历史街区、古村古镇保护经验研究”(编号:24VWB022)
国家自然科学基金项目“山地传统聚落洪涝适灾机理解析与应用研究”(编号:52478039)。
