渭河下游洪水灾害的降水危险性评估与区划  

Evaluation and Regionalization of Precipitation Fatalness for Flood in Lower Reacher of Weihe River

作　　者：李景宜[1,2] 

机构地区：[1]陕西省灾害监测与机理模拟重点实验室,宝鸡文理学院地理科学与环境工程系,陕西宝鸡721013 [2]兰州大学西部环境教育部重点实验室,甘肃兰州731000

出　　处：《中国人口·资源与环境》2011年第2期106-111,共6页China Population,Resources and Environment

基　　金：国家自然科学基金(No.40501077);教育部新世纪优秀人才支持计划(No.NCET-10-0874);陕西省自然地理学重点学科;陕西省重点实验室项目

摘　　要：大气降水的不规则运动是引发洪水灾害的重要因素。通过对"小洪水、大灾情"特性显著的渭河下游洪泛区的洪水特性、降水规律以及二者的关系进行分析,利用插值计算法进行降水量和降水变率空间分析,评估并区划了研究区汛期洪灾风险的降水危险性。主要结论为:①季节性的强降水过程是引发渭河下游洪水灾害的重要因素,连续暴雨或大范围暴雨往往带来洪水灾害;②汛期降雨量呈现出显著的南多北少特征,且从东南到西北依次递减,咸阳、高陵县、大荔县西北部降水量偏低,而秦岭北麓的华县、华阴及西安市区降水相对丰富;③汛期降水变率虽然呈现出相间分布的特征,但降水量变化较大的区域(西安市区、华县以及潼关县东南部)都集中于南部的秦岭北麓;④根据降水量越大,影响度越高,降水变率越大,降水量越不稳定,洪水危险性越高的原则,进行洪灾的降水危险性评估与区划,结果显示降水危险性较高与较低区域呈环状相间分布,危险性较高的区域更多地分布于渭河干流南岸。Erratic behavior of precipitation is the important factor which causes flood disaster.Flood characteristics,precipitation variation and their relationship were analyzed.By interpolating algorithm for precipitation and its change rate,precipitation fatalness in flood season was evaluated and zoned.Seasonal strong precipitation is the important factor that causes flood disater in lower reacher of Weihe River.Continuous torrential rain and wide range rainstorm usually fetch flood disaster.Precipitation in flood season shows descending remarkably from southeast to northwest by turns.It is on the low side in Xianyang,Gaoling and northwest of Dali.And it is abundant comparatively in northern slope of Qinling,such as Huaxian,Huayin and Xi＇an.Change rate of precipitation shows interphase distribution.Remarkable variation regions all converge in northern slope of Qinling,such as Xi＇an,Huaxian and southeast of Tongguan.Based on the principle between precipitation and its change rate,higher fatalness of precipitation regions alternate with the lower regions,and the higher regions usually distribute circlewise on the southness shore of mainstream watershed of the Weihe River.

关 键 词：渭河下游 洪灾危险性 降雨量 降雨变率 

分 类 号：P333[天文地球—水文科学]