5种干旱指数在吉林省农业干旱评估中的适用性

干旱是对吉林省农业生产影响最大的气象灾害,干旱指数能够表征农业旱情,但不存在普遍适用的干旱指数,开展干旱指数在吉林省农业干旱评估中的适用性研究具有重要的现实意义.基于1961-2014年吉林省的逐日气象数据、土壤水分资料和历史旱情统计信息,选取典型干旱年和典型干旱区,评估了降水量距平百分率(PA)、相对湿润度指数(MI)、作物水分亏缺距平指数(CWDIa)、帕默尔干旱指数(PDSI)和气象干旱综合指数(MCI)共5种干旱指数在吉林省农业干旱评估中的适用性.结果表明:对于1997和2007年两个典型旱年,MI对农业旱情的评价结果与旱情记录较一致,PA和MCI次之.对于吉林省典型旱区(西部通榆、中部梨树、东部和龙),MI和PDSI对农业旱情的评估较好.在农作物生长季,PA较适用于评价4、7和8月的旱情,MI较适用于评价4、5和9月的旱情,CWDIa只适用于评价5月的旱情,PDSI对6-9月的旱情均有一定的指示作用,MCI适用于5-8月的农业干旱过程评估.从农业干旱发生范围来看,MI、PDSI和MCI较适用于评估吉林省西部旱情,PDSI较适用于评价吉林省中部旱情,PA、PDSI和MCI较适用于评估吉林省东部旱情.

Applicability of five drought indices for agricultural drought evaluation in Jilin Province,China.

Drought is a severe meteorological disaster on agriculture in Jilin Province. Agricultural drought can be represented by drought indices, but there is no universal applicable index. It is of great significance to examine the applicability of drought indices for agricultural drought evaluation. Based on daily meteorological data, soil moisture data, and drought statistical information from 1961 to 2014, we selected typical drought years and typical drought zones. The applicability of five drought indices was evaluated, including precipitation anomaly percentage (PA), relative moisture index (MI), crop water deficit anomaly index (CWDIa), Palmer drought severity index (PDSI) and meteorological drought comprehensive index (MCI). The results showed that agricultural drought evaluation of MI was consistent best with drought information for two typical drought years of 1997 and 2007, followed by PA and MCI. For typical drought zones (Tongyu in the west, Lishu in the center and Helong in the east), MI and PDSI performed much better than other ones. During growing season, PA was more applicable in April, July and August, MI was applicable to April, May and September, CWDIa only performed well in May, PDSI could be an indicator to agricultural drought in June, July, August and September, MCI was useful in May, June, July and August. For different regions with agricultural drought, MI, PDSI and MCI were applicable in western region, PDSI in central region, and PA, PDSI and MCI were suitable for eastern region.