泾惠渠灌区干旱指数的变化趋势及其敏感性分析  

Trend and sensitivity of aridity index in Jinghuiqu irrigation area

作　　者：钟锋[1] 粟晓玲[1] 宋悦[1] 

机构地区：[1]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《自然灾害学报》2015年第6期97-104,共8页Journal of Natural Disasters

基　　金：国家自然科学基金项目(51279166);水利部公益性行业专项经费项目(201301016)~~

摘　　要：干旱指数是监测、预警、评估干旱的关键参数。将干旱指数用参考作物蒸发蒸腾量ET0与降水的比值来表示。根据泾惠渠灌区4个气象站近50年的气象资料,采用Penman-Monteith公式计算ET0,利用Mann-Kendall趋势检验法研究了降水、ET0及干旱指数的变化趋势,采用敏感系数法分析了干旱指数对气象因子的敏感性。结果表明:灌区ET0呈显著下降趋势,降水和干旱指数呈非显著下降趋势;灌区西北部趋于干旱,东南部趋于湿润,春秋两季趋于干旱,夏冬两季趋于湿润;干旱指数对降水最为敏感,其次为最高气温和水汽压。Aridity index,as the ratio between evapotranspiration（ ET0） and precipitation,is a key parameter to morniter,early warn and assess aridity. In this study,daily ET0 was estimated using the Penman- Monteith equation with the observed daily meteorological data from 1961 to 2011 at four meteorological stations located in Jinghuiqu irrigation area. The trends of precipitation,ET0 and aridity index were studied by Mann- Kendall test. A sensitivity coefficient method was employed to analyze the sensitivity of aridity index to meteorological factors. The results show that,annual ET0 in irrigation district has a significantly decreasing trend,while precipitation and aridity index has slightly decreasing trends. The northwest parts of the irrigation district shows a dryer trend while the southeast part shows a wetter trend,and this district tends to be dryer during spring and autumn,while wetter during summer and winter. In general,precipitation is the most sensitive variable,followed are the maximum temperature and vapor pressure.

关 键 词：干旱指数 变化趋势 敏感性 泾惠渠灌区 

分 类 号：S423[农业科学—植物保护]