River network-based index to clarify transmission of hydrological drought in reservoir-regulated basins

• DOI: 10.1016/j.ejrh.2023.101604
• Publication Date: 2023-12-14T16:31:58Z
• Authors: Mi Zhou; Lihua Xiong; Cong Jiang; Gang Chen; Chengkai Liu; Xini Zha
• Keywords: Physical geography; QE1-996.5; Standardized streamflow index; River network; 0208 environmental biotechnology; Geology; 02 engineering and technology; Hydrological drought; Reservoir regulation; Hierarchical model; GB3-5030

Hanjiang River basin (HRB), China. Understanding the transmission of hydrological drought along river networks is extreme importance for monitoring, forewarning, and mitigation drought. However, it extremely difficult to do so under situation complex networks, particularly in presence spatially distributed reservoirs. Taking advantage reasoning information within a hierarchical network structure, this study proposed nonstationary standardized streamflow index (NSSIrn) clarify reservoir-regulated basins. Then, generalized regression model based on normal distribution was used networks. The NSSIrn aided with enables reservoir-induced alteration be better clarified conditions. NSSIrn-based characteristics determined throughout HRB showed that droughts occurred downstream region were more severe longer lasting than those upstream during 1957–2019. Moreover, regulation Danjiangkou reservoir weakens correlation between droughts, i.e., roughly one quarter events did not develop into reservoir. This offers valuable reference evaluating effect other interventions human-modified