淮河流域陆地水储量与干旱指标分析

基于GRACE卫星数据、MODIS数据和降水数据分析了2003—2016年淮河流域陆地水储量、植被指数和降水的多年时空变化，并探究标准化陆地水储量指数(SWSI)、标准化降水指数(SPI)与条件植被指数(VCI)对流域干旱的指示性。结果表明:淮河流域陆地水储量呈显著下降趋势，降水量微弱下降，植被覆盖率显著上升；SPI与VCI相关性较高，与SWSI变化较为一致；SWSI与SPI指示的不同等级干旱月份数量基本相当，明显小于VCI；SPI对淮河流域历史干旱存在漏报，VCI指示的干旱等级略偏高；SWSI整体表现较为良好，能够有效监测淮河流域旱情。

Analysis of terrestrial water storage and drought indices in the Huaihe River Basin

The spatio-temporal variations of terrestrial water storage, vegetation index and precipitation in the Huaihe River Basin from 2003 to 2016 were studied based on GRACE satellites data, MODIS data and precipitation data. We further discussed the indication of standardized water storage index(SWSI), standardized precipitation index(SPI)and vegetation condition index(VCI)to the watershed drought. The results show that the terrestrial water storage in the Huaihe River Basin is in a significant trend of decline, and the average annual precipitation shows a slight decline, while the average annual vegetation coverage rises significantly. The correlation between the SPI and VCI is relatively high, which is in a good consistency with the variation of SWSI. The numbers of months with drought at various levels indicated by SPI and SWSI are almost the same and are much less than that indicated by VCI. The historical drought in the Huaihe River Basin is underreported by SPI and the drought level indicated by VCI is slightly higher. The overall performance of SWSI is good, which can monitor the drought situation in the Huaihe River Basin effectively.