作者：W. Yu, F. Liu, X. Jiao, P. Fan, H. Yang, Y. Zhang, et al.

Lakes and reservoirs are hotspots for emissions of atmospheric greenhouse gas (GHG) such as CO2, CH4, and N2O, and their nutrient levels and stoichiometric status are significant drivers of GHG emissions. In recent decades, human-induced unbalanced inputs of nitrogen (N) and phosphorus (P) have enhanced the P-limiting state of inland lake and reservoir systems. However, it remains unclear whether this state transition involves global changes in nutrient-limiting systems and GHG emissions from lakes and reservoirs. In this study, a comprehensive model was developed to examine the relationship between GHG fluxes and total N (TN) and total P (TP) to predict future human-induced N over-enrichment and its impact on global GHG emissions. Our results show that excess N inputs amplified GHG emissions, with future water eutrophication (1.2x) projected to increase CO2 emissions (384.66 Tg center dot y-1), CH4 (7.38 Tg center dot y-1), and N2O (0.23 Tg center dot y-1) from lakes and reservoirs by 49 %, 12 %, and 25 %, respectively, amounting to approximately US$0.13 trillion ($0.08-6.91 trillion, 2015$) in social costs. A future 50 % increase in N: P will increase the relative social cost of carbon by 15 % compared to future 1.2x eutrophication levels. Given the social costs and benefits of reducing N and P pollutants in water individually and in synchronization, future long-term strategies for managing eutrophication in lakes and reservoirs need to emphasize balanced control of N and P.

（来源：Water Research 2025 Vol. 276   DOI: 10.1016/j.watres.2025.123240）