[Impacts of International River Hydropower Development on Multidimensional Ecosystem Services and Their...

Clarifying the complex effects of hydropower development on international river ecosystems is essential for balancing development, conservation, sustainable growth, and maintaining stable international relations. Focusing on the Lancang-Mekong River Basin (LMRB), this study used the InVEST model to quantify five key ecosystem services (ESs), including food production (FP), water yield (WY), soil conservation (SC), carbon storage (CS), and habitat quality (HQ), from 1990 to 2020. By examining hydropower development characteristics along both the main and tributary rivers, it reveals the evolution of multidimensional ESs and their trade-offs or synergies across two periods: 1990-2005 and 2005-2020. The results showed: ① SC, CS, and HQ generally exhibited a "northeast high, southwest low" distribution, while FP showed the opposite, and WY displayed a "low upstream and downstream, high midstream" and "east high, west low" pattern. ② There was a complex correlation between the kernel density changes of hydropower station and the multidimensional changes in ESs. Upstream hydropower development increased downstream WY and SC with significant spatial heterogeneity but had minimal impact on CS and HQ. Downstream hydropower development slightly increased WY, SC, and CS, while reducing HQ in localized regions. ③ ESs in the LMRB showed a "cooperative with partial trade-off" relationship, with mainstem hydropower development fostering WY-SC, WY-CS, and WY-HQ synergies and enhancing the CS-HQ trade-off. Tributary hydropower development intensified WY-SC, WY-CS, and WY-HQ trade-offs, while promoting WY-FP synergy. This study provides a scientific basis for international river ecosystem protection, sustainable socioeconomic management, and resolving hydropower-related disputes.