新疆春夏洪灾受灾面积长期变化趋势及其对农作物的影响  

Variation trend in spring-summer flood disaster area and its effects on crops in Xinjiang

作　　者：王秋香[1] 吴彦 叶殿秀[3] 李秦[1] 

机构地区：[1]新疆气象信息中心,新疆乌鲁木齐830002 [2]新疆气象台,新疆乌鲁木齐830002 [3]国家气候中心,北京100081

出　　处：《干旱区地理》2009年第3期430-437,共8页Arid Land Geography

基　　金：中国气象局气象灾害风险区划示范试点建设--项目资助;中国沙漠气象科学研究基金(sqj2005004)资助;国家自然科学基金项目"新疆北部气候突变及其对生态环境的影响"(40475041)资助

摘　　要：选用新疆1950-2006年84个县2038条洪水灾害资料,以春夏3～8月洪灾受灾面积为研究对象,用最小二乘法与二阶主值函数分析各月受灾面积的长期变化趋势,非参数化秩统计量做趋势的显著性检验,计算累计距平值判定时间序列的拐点,以拐点前后的变差系数比较受灾面积振幅的变化,采用morlet小波分析其振荡周期发现,春季3～5月农作物苗期是融雪洪水多发季节,洪灾受灾面积占全年的37%,各月受灾面积均有长期增加的趋势。其中,春季洪灾高发期的5月增加趋势十分显著,平均每年增加2.01%,是春季农田防洪的重点时期。夏季6～8月各种农作物的旺盛生长期,是暴雨洪水的频繁发生期,受灾面积占全年的60%,夏季各月洪灾受灾面积均有长期增加的趋势,其中,洪灾高发期的6、7月增加趋势十分显著,7月平均每年增加2.13%,6月增加1.86%,因此6、7月是夏季农田防洪的重点时期。另外,洪灾高发期的5、6、7月存在12～15年、5～7年的振荡周期,以及2～3年的小扰动,各类周期振荡在拐点之前比较弱,之后振荡较强。其中,春季3、4、5月拐点在1984年,夏季6、7、8月拐点分别在1974年、1986年和1988年。同样以拐点为界,之前是洪灾少发时期,之后即开始处于洪灾频发期气候背景上的年代际与年际尺度振荡,另外,拐点前后平均受灾面积相差很大,增幅在58%～164%之间。Spring and summer are the seasons of crop seeding and also the high-incidence period of flood disasters in Xinjiang. However, the recent studies of flood disasters were mainly based on annual scale, which induced that many smaller-scale differences of flood disasters were smoothed or omitted, and caused many characteristics of flood disaster law and differences in various seasons could not be well reflected. Based on flood disaster data of eighty four counties of Xinjiang from 1950 to 2006, this paper analyzed the tendency and period of flood disaster areas from March to August in Spring and Summer and the impacts on crop to make out the law and tendency of monthly flood disaster in high-incidence seasons to fine the key flood combating month, and to form a basis for rational disaster prevention in crop planting period in Xinjiang. The paper analyzed the long term tendency and law of flood disaster area from various views, i. e. , revealing the long term tendency of monthly flood disaster area with least square method and second order principal value function, contrasting the tendencies with mean difference method and climate tendency coefficient method simultaneously, conducting significance test of the tendency with nonparametric rank-based statistics method, determining the inflection point with accumulative anomaly calculation, comparing the oscillation amplitude of flood disasters with the variation coefficients before and after the inflection points and analyzing the oscillation periods with morlet wave-let method. The results showed as follows ： （ 1 ） in the period from March to May, the sowing and seedling flood disasters caused by snow-melting and stage of the main crops of wheat, corn, cotton and rice in Xinjiang, ice slush blocking riverway occur frequently, and the disaster area makes up 37 percent of total of the whole year. The tendencies of disaster areas in various months in spring calculated with different methods show positive values, i. e. , the disaster areas in all months have the long

关 键 词：新疆 洪灾 春夏 受灾面积 变化 趋势 周期 频发期 

分 类 号：S422[农业科学—植物保护]