Abstract
Reservoir construction and operation profoundly alter the hydrological,hydrodynamic,and carbon and nitrogen cycling processes of rivers.However,current research still lacks a systematic understanding of the characteristics of greenhouse gas(GHG)emissions from reservoirs in arid/semi-arid regions.This study integrates existing monitoring data to discuss the characteristics of GHG emissions from reservoirs in the Yellow River Basin and illustrate the controlling factors and underlying mechanism of these processes.The results indicate that while CO2 emission flux from reservoirs is lower than that from river channels,the emission fluxes of CH4 and N2O are 1.9 times and 10 times those from rivers,respectively,indicating that the emission of GHG with stronger radiative effect is significantly enhanced in reservoirs.Compared to the reservoirs in humid climates(e.g.,the Three Gorges Reservoir),reservoirs in the Yellow River Basin exhibit relatively lower emissions of CO2 and CH4 due to lower organic matter concentrations,but significantly higher N2O emissions due to higher nitrogen loads.Monte Carlo simulations for 237 reservoirs in the Yellow River Basin showed that total emission of the three GHGs is 3.05 Tg CO2-eq yr-1,accounting for 0.39％of the total emission from global reservoirs and lower than the area percentage of the basin(0.53％).This study has important implications on revealing the GHG emission characteristics and control mechanisms of reservoirs in arid/semi-arid regions.
基金项目
National Key Research and Development Program of China(2021YFC3200401)
National Natural Science Foundation of China(52379057 & 52039001)
维普
万方数据