ISEHSD: a feedback-based, integrated social-ecohydrological system model for studying basin-level transformation

Models are essential for representing the complex interactions that shape human–water systems, yet existing approaches often struggle to capture basin-specific feedbacks and to support systematic sustainability assessments at the river-basin scale. Here, we develop a generic and extensible Integrated Social–Ecohydrological System Dynamics (ISEHSD) model that explicitly couples social, ecological, and hydrological processes within a unified feedback structure. The framework represents dynamic interactions across eleven interconnected sectors and enables basin-scale sustainability assessment based on biophysical boundaries, capturing outcomes arising from both natural dynamics and human interventions. ISEHSD explicitly resolves the co-evolution of agri-food systems, water, and ecological impacts. The framework is demonstrated through a use-case implementation for the Yellow River Basin, an arid river basin subject to intensive anthropogenic pressures. Global sensitivity analysis and uncertainty quantification are employed to identify key nonlinear interactions and to evaluate alternative development and management strategies. Results indicate that severe water stress is not expected to be relieved before 2045 under the scenario analysis. Even under the most sustainability-oriented scenario, human water demand could exceed the severe water stress threshold by 22% (ranging from 6% to 40%) in 2100. Cross-system transformations, including enhanced water efficiency and sustainable agricultural practices, remain essential to reducing water stress in the basin. Beyond this application, ISEHSD provides a scalable and interpretable modelling framework that supports multi-scenario policy analysis, integrated visual analytics, and stakeholder-oriented dialogue for river-basin sustainability planning.