Modeling Land Use Dynamics under Climate and Hydrological Changes: An Integrated Hydro-Land Framework.

Area of Science:

• Environmental Science
• Hydrology
• Climate Science

Background:

• Climate change and hydrological variability significantly influence land-use dynamics.
• Existing one-way models inadequately represent nonlinear soil-water feedbacks in coupled systems.

Purpose of the Study:

• To develop a cascaded land-hydrology coupled modeling framework (LaHyFr) that captures bidirectional soil-water interactions.
• To improve the simulation of land-use dynamics under changing climate conditions.

Main Methods:

• Integrated hydrological (SWAT) and land-use (CLUE-S) modules with dynamic parameter adjustment.
• Incorporated spatiotemporal downscaling for scale harmonization.
• Established a closed-loop mechanism of "hydrological stress-land response-process feedback."

Main Results:

• LaHyFr improved hydrological simulation accuracy (R² by 13.33% calibration, 18.05% validation) and reduced water balance error (1.4% calibration, 2.6% validation).
• Land-cover simulation performance increased (AUC by 11.31%, Kappa by 12.32%).
• Model accurately captured nonlinear soil-water responses across different climate scenarios.

Conclusions:

• The LaHyFr framework offers a robust, transferable tool for analyzing coupled climate-hydrology-land dynamics.
• The model supports effective watershed management and climate adaptation planning by providing mechanistic insights.
• The bidirectional feedback mechanism enhances the understanding of complex environmental system interactions.