摘要
Comprehensively revealing the intensity of drought propagation from meteorological to hydrological drought is crucial for effective drought monitoring and management.However,existing assessments often fail to integrate multiple drought characteristics,resulting in incomplete evaluations.To address this limitation,this study introduced the drought comprehensive propagation intensity(DCPI)index,a systematic tool that quantifies propagation intensity and incorporates five drought characteristic indicators(drought frequency,total duration,maximum duration,coverage,and degree)to assess the comprehensive drought intensity in the upper Shiyang River Basin,China from 1961 to 2023.The results indicated that pre-1980s drought propagation was relatively weak(DCPI<0.964),reflecting stable hydrological homeostasis.After the 1980s,the intensity significantly increased,peaking at 5.530(rather strong drought)in the 2000s due to human-induced alterations in surface runoff and ecological changes.Spatially,the western tributaries(e.g.,the Xida River Watershed)presented stronger hydrological drought intensity,whereas the eastern tributaries(e.g.,the Huangyang,Gulang,and Dajing river watersheds)presented higher meteorological drought intensity.The DCPI values decreased from west to east,with near peer-to-peer propagation observed in the Dongda,Huangyang,and Jinta river watersheds,suggesting minimal human interference.A nonlinear relationship between meteorological and hydrological droughts was identified,with severe drought frequency and duration emerging as critical drivers of propagation intensity.Notably,trends of meteorological humidification coexist with hydrological aridification,highlighting systemic challenges for water resource management.The DCPI framework enhances the understanding of drought mechanisms by enabling a structured evaluation of drought impacts,which is essential for developing effective water resource strategies and ecological restoration efforts in arid areas.This study underscores the importance of integrating multi-dimensional drought characteristics to improve prediction accuracy and inform policy decisions.
基金
supported by the National Natural Science Foundation of China(42475177,41877521)
the National Key Research and Development Program of China(2023YFC3008505,2016YFA0602402).
