Enhanced Climate Mitigation Feedbacks by Wetland Vegetation in Semi-Arid Compared to Humid Regions

Wetlands are recognized for their climate mitigation potential through carbon storage and local cooling effects. Yet, the spatial variability of how wetland vegetation influences local climates via biogeophysical process remains poorly understood. Here, we examine the impacts of wetland vegetation changes on land surface temperature (LST) across the Amur River Basin using satellite data and model simulations. Our results reveal significant cooling effects associated with increased wetland vegetation, with the strongest cooling observed in semi-arid areas (−1.12°C m² m⁻²), compared to semi-humid (−0.46°C m² m⁻²) and humid zones (−0.45°C m² m⁻²). Decoupling biogeophysical pathways reveals that atmospheric feedback, aerodynamic resistance and surface resistance accounted for 44.4%, 41.5%, and 13.3%, respectively, of the diagnosed LST sensitivities to leaf area index in semi-arid regions, whereas aerodynamic resistance and atmospheric feedback contributed 75.2% and 23.8%, respectively, in humid regions. Our findings suggest wetland vegetation restoration, particularly in semi-arid regions, could provide substantial climate mitigation benefits through biogeophysical process.