Estimation of a trend of meteorological and hydrological drought over Qinhuai River Basin

This study aims to improve the understanding of meteorological and hydrological droughts in the Qinhuai River Basin. The multiple drought indices deciles, standardised precipitation index (SPI), reconnaissance drought index (RDI), and streamflow drought index (SDI) were used to understand the characteristics of droughts. Non-parametric tests, such as the Mann-Kendall (MK) and Sen’s slope, were used to determine the trend of droughts. The indices were calculated for multiple temporal scales from 1 to 12 months. The results showed that 1993–1994 and 2013–2014 were drier years with slight severity variation, which was commonly detected by all indices on a 12-month temporal scale. A higher correlation was found for 12-month temporal 0.95 and 0.93 RDI. Approximately 70% (northern) had a slight drought, and the 30% (southern) study area had no drought in autumn. Similarly, there was no drought during the summer and winter. A significant upward trend in January was detected at all the stations. A significant downward trend in September was detected at the Jurong station.