【摘要】 氧化亚氮的释放已经成为了一个全球性的环境问题,水体中N₂O的释放量会随着氮含量的增加而增加.本文通过微宇宙系统的构建,分析氮的转化过程和氮转化基因的变化,并结合结构方程模型分析了温度、氨氮含量对水体N₂O释放的贡献.研究结果发现氨氧化古菌和反硝化细菌丰度均与N₂O释放呈正相关,表明水体中的硝化和反硝化作用都会造成N₂O的释放.氨氮浓度的升高并不直接促进N₂O的释放,而温度和通过硝化作用产生的硝态氮对N₂O的释放有促进作用.此外,硝化速率通过促进亚硝态氮和反硝化菌的丰度而间接地促进N₂O的释放.更多还原

【Abstract】 The increase of nitrous oxide emission has become a worldwide problem. The emission of nitrous oxide from water body increased with the increase of N inputs. Our study analyzed the roles of temperature and ammonia in N₂ O emission through quantification of nitrogen transformation and related functional genes. The results showed that the abundance of ammonia oxidizing archaea and denitrifiers positively correlated to N₂ O emission in water. Structural equation model revealed ammonia content had no direct effect on N₂ O emission, however, high temperature and nitrification directly accelerated the release of N₂ O. In addition, nitrification process also increased the release of N₂ O indirectly through promoting abundance of denitrifiers and nitrite content.更多还原