基于多指标评价的南流江流域气象-水文干旱传播特征研究OA

Investigating drought propagation characteristics has become a major focus in drought research.Clarifying the propagation time and critical conditions of different types of drought is of great significance for drought-resistant regulation and emergency management within the basins.Based on precipitation data and the daily average flow of major hydrological stations in the Nanliu River from 1961 to 2022,the Standardized Precipitation Index(SPI)and the Standardized Runoff Index(SRI)are used to represent meteorological and hydrological droughts,respectively.Through parameters like drought lag time,response time,and propagation thresholds,this study quantifies the dura-tion and severity of meteorological-hydrological drought propagation within the basin.The results show that:The variations in SPI and SRI exhibit a high degree of consistency,with hydrological droughts occurring more frequently;however,the occurrence of extreme and severe meteorological droughts is more frequent;The propagation from meteorological to hydrological drought shows a lag effect,with average lag times of 0.3 months at Bobai station and 0.6 months at Changle station,and a response time of 2 months at both stations;The drought duration propagation thresholds for Bobai Station and Changle Station are 2.3 months and 1.8 months,respectively,while the drought severity propagation thresholds are 0.7 and 2.2,respectively.The results of this study provide a scientific basis for early drought prevention and mitigation efforts in Guangxi's coastal region.