关中地区降水特征及其对旱涝灾害的影响

Characteristics of Precipitation and Its Influence on Drought and Flood Disaster in Guanzhong Area

为了减少关中地区降水引发的旱涝灾害带来的损失,基于关中地区各市站30~60a的降水量数据,运用数理统计并结合Mann-Kendall突变检验法对该地区降水量的Z指数进行了分析,就关中地区降水对旱涝灾害的影响做了研究。结果表明:(1)关中地区降水量相对比较丰富,但极差较大,易出现旱涝灾害,旱涝发生的总年份占研究序列的41.33%。其年内旱涝程度的分布与年际基本一致,但各地区分布又不尽相同。(2)关中地区冬春季Z指数朝着干旱化的趋势发展,且春旱更严重;夏秋季旱涝灾害均易发生且频繁,为主要的防灾期。(3)关中地区的旱涝变化交替出现,但总体趋势正在向着偏旱的趋势发展。该研究为关中地区旱涝灾害的防治提供了一定的科学依据。

In order to reduce drought and flood disaster losses caused by the precipitation in Guanzhong area,based on the precipitation data of each city in Guanzhong area during 30~60 years,the Zindex of precipitation in this region was analyzed by mathematical statistics and Mann-Kendall mutation test and the influence of precipitation on flood disaster in Guanzhong area was studied.The following conclusions are drawn.(1)The precipitation was relatively rich and had a large range which was prone to cause drought and flood disasters,and the years of drought and flood disasters accounted for 41.33% of the sequence.The years and annual distribution of drought and flood were basically the same,but the regional distribution was not same among the regions.(2)There was a drought tendency in the winter and spring,and drought was more serious.On the contrary,drought showed an increasing trend summer and autumn,however,drought and flood disasters were easy to occur and frequent.(3)The variation of flood and drought appeared alternately,but the overall trend was toward the direction of the development of drought.This study can provide a scientific basis for the prevention and control of flood and drought in Guanzhong area.