我国东部典型内源和外源性静态水体N2O排放 与生态系统呼吸的关系初探.

Inland waters emit large amounts of nitrous oxide (N2O) to the atmosphere, which has attracted extensive attention worldwide. The goal of this study was to investigate the relationship between N2O flux and ecosystem respiration (ER) in aquatic ecosystems. We measured N2O and ER in 10 typical exogenous and endogenous static water bodies in eastern China and identified the relationship between N2O flux and ER in the aquatic environments using a Bayesian method from April 29 to May 4, in 2022. The results showed that N2O flux and ER were significantly higher in exogenous water bodies than in endogenous water bodies. There was a significant positive correlation between N2O flux and carbon dioxide (CO2) flux and BOD5 in the water. The Bayesian model explained 61% to 71% of the variability of N2O flux and clarified the uncertainty of the model. We also distinguished the relationship between N2O flux and ER in endogenous and exogenous water bodies. In endogenous water bodies, the effect of carbon source limitation on N2O flux is greater than the effect of nitrogen source limitation. However, the coupling relationship between N2O and CO2 is stronger in exogenous water bodies than in endogenous water bodies. In summary, ER indirectly promotes N2O emission, which provides a basis for an estimation method of N2O flux from water bodies and the coupling mechanism of ER. [ABSTRACT FROM AUTHOR]