Future climate change impacts on carbon dynamics and ecohydrological risks in the West Liao river Basin, China: implications for carbon management.

The climate system is undergoing unprecedented and dramatic changes, with increasing frequency and intensity of extreme events such as heat waves, droughts and heavy rainfall. Climate change has triggered profound changes in the global carbon cycle and eco-hydrological processes, posing unprecedented challenges for watershed carbon management, and quantifying climate-driven eco-hydrological processes remains critical for achieving watershed-scale carbon neutrality. In this study, we developed an integrated modeling framework combining Biome-BGC, GBHM and RWEQ models, aiming to comprehensively assess the ecohydrological processes and carbon cycle changes in the west liao River Basin (WLRB). Our results suggest that the future climate of the WLRB (1991-2100) will shift towards a warmer and wetter climate, accompanied by decreasing wind speeds but increasing extreme wind events. These changes drive three key carbon-climate feedbacks: warmer maximum temperatures lead to degradation of vegetation productivity in the plains, weakening watershed carbon sequestration capacity and reducing the sensitivity of vegetation to precipitation in the semi-arid zone. Increased frequency of extreme wind speeds greatly increases the potential for wind erosion in the WLRB, threatening soil organic carbon storage. From the perspective of aquatic carbon pools, despite reduced drought risk and increased water availability, there is a strong likelihood of increased frequency and intensity of flooding, which may exacerbate lateral carbon export. Our findings highlight that climate change amplifies synergistic risks to terrestrial and aquatic carbon pools, requiring adaptive strategies such as establishing synergistic vegetation restoration models that integrate windbreak-carbon sequestration with flood regulation. These findings not only improve our understanding of the evolutionary mechanisms and potential risks of ecohydrological processes, but also provide guidance for future watershed carbon management.