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

内陆水体是大气中N₂O的重要排放源，受到国内外广泛关注，为了探讨水生生态系统中水体N₂O排放通量与生态系统呼吸的响应关系，本研究以我国东部典型外源性和内源性静态水体为研究对象，在2022年4月29日—5月4日对10个表层水体N₂O排放通量和生态系统呼吸指标进行测定，结合贝叶斯方法初步探讨了水体N₂O排放通量和生态系统呼吸之间的关系。结果表明：外源性水体N₂O排放通量和生态系统呼吸均显著高于内源性水体(P<0.05)，水体N₂O排放通量与CO₂排放通量和BOD₅均呈显著正相关关系(P<0.05)。通过贝叶斯方法构建了水体N₂O排放通量与生态系统呼吸(CO₂和BOD₅)之间的数学模型，可解释水体N2O排放通量变异性的61%～71%，并且明确了模拟结果的不确定性。此外，本研究进一步区分了内源性水体与外源性水体N₂O排放通...

Preliminary study of the relationship between N2O emission and ecosystem respiration in typical endogenous and exogenous static water bodies in eastern China

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.