SPI指数和Z指数在青海省东部农业区应用分析

An Applied Analysis of SPI and Z Index in Qinghai Provincial Agricultural Regions in the East

以青海省东部农业区12个气象站点1959-2005年49a各月的降水量为基础,计算该区的标准化降水指数SPI和Z指数,并分析两者在青海省东部农业区的一致性、显著周期和干旱等级一致率。结果表明:利用SPI指数和Z指数定义青海省东部农业区干旱等级时,两者的相伴概率值较大,且有多个相同的显著周期;等级值一致率均在0.79以上,SPI指数和Z指数在定义重旱等级时,两者的等级值一致的月数较多,SPI指数和Z指数定义轻旱等级的等级一致月数则有明显的区域性,SPI指数和Z指数在评价青海省东部农业区的干旱等级上有很好的一致性。

Based on the monthly precipitation of 12 weather stations in Qinghai Provincial agricultural regions in the east ,from 1959 to 2005 （49 a） .S PI and Z index in the study area is calculated ,the consistency of single station is analyzed ,significant cycle and concordantratesofdroughtdegreearecalculated ,whichusedSPIandZindex.TheresultsshowthatusingtheSPIindexandZin‐dex define the drought degree in Qinghai Provincial Agricultural regions in the east ,their concomitant probability value is high ,and there are many same cycles .All concordant rate of drought degree has the value more than 0 .79 .The SPI index and Zindex is used to define the serious drought ,there are concordant degree in the more number of month .The concordant rate of drought degree has obviousqualityofregionalwhentheSPIindexandZindexareusedtodefinethelightdrought.SPIandZindexintheevaluationof agricultural drought has a good consistency in Qinghai Provincial Agricultural regions in the east .