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• A multiple-drought cascading framework based on causal inference was proposed. • Multiple-drought cascading risks were quantified by considering multiple time lags and complex factors. • The cascading risk of SD and GD peaks at a 3-7 month lag, during which time GD is most significantly influenced by vegetation. Comprehensively evaluating evolution of drought has an important guiding significance to drought early warning systems and disaster control. Drought is a major natural disaster. Although there are multiple methods including statistics to study drought propagation at present, the evolution of droughts is a complex phenomenon, existing physical and data-driven methods demonstrate unsatisfactory estimation performance. To address this issue, a new type of multiple-drought cascading framework was proposed. The peculiarity of this framework is that based on the principle of causal inference, a generalized linear regression model was established to quantify cascading effect of multiple droughts in disaster chain systems and explore influences of complicated factors outside the system on the cascading effect. The proposed framework was evaluated based on meteorological, soil and groundwater drought conditions of the Yanhe River basin, China. The results prove that study from the perspective of cascading disasters can intuitively characterize disasters of different types of drought signal propagation in the disaster chain system. The results also revealed a top-to-down drought long-chain cascading relationship in moisture transfer in the atmosphere, pedosphere, and lithosphere and discovered that climate change and vegetation restoration are the primary influencing factors of different links. In the framework, a novel model was constructed to quantify multiple-drought cascading effect considering influences of complex factors to facilitate the enhancement of policy planning and can help reduce negative influences of multiple cascading disasters. This framework is also expected to be applied in other areas to enrich the understanding of mechanisms underlying multiple-drought cascading disasters. [ABSTRACT FROM AUTHOR]

• A novel social-ecological coupling model was established. • The degree of coordinated development of human-water relationship in the basin was quantified by the characteristic parameters in the Budyko framework. • The human-water relationship will reach moderate coordination development in the future is predicted. Correctly understanding the coordinated development between the social economy and the ecological environment is the key to achieving the sustainable development of river basins. Previous coupling coordination degree models are empirical ones and very complex, without physical parameters. Here, a novel social-ecological coupling model was established to meet the challenge. Within the Budyko framework, n D was adopted to characterize the social-ecological coupling coordination degree of the human-water relationship in basins. In addition, a social-ecological coupling coordination model with basins in northern Shaanxi Province, China as units. The multiple linear regression (MLR) model was used to quantitatively analyze the evolutional relationship between economic development and ecological environment. Research results show that R2 is larger than 0.6 in the comprehensive evaluation results of the novel model. This means that the model can well reflect changes in vegetation coverage and simplify expression of the coordinated development of social-ecological systems. The evaluation results of the human-water relationship in the basins are gradually improved year by year and the coordination state evolved constantly. The two systems have positive promotion effects on each other. The social-ecological coupling coordination degree (D) is spatially different, and various basins are listed in a descending order as the Yanhe, Wuding, and Kuye river basins according to D. D of the three basins all evolves from 0.2 (moderate incoordination) to 0.6 (mild coordination). Combined with analysis of ARIMA time series, it is anticipated that the human-water relationship will reach moderate coordination by 2030. Finally, without changing the premise of the social-ecological coupling model, limitations of the current model factors can be improved for future research to provide policy suggestions exploring ways to coordinate development of social-ecological systems in northern Shaanxi. [ABSTRACT FROM AUTHOR]