驱动稻田N2O排放关键过程的微生物作用机理

项目名称： 驱动稻田N2O排放关键过程的微生物作用机理

项目编号： No.41330856

项目类型： 重点项目

立项/批准年度： 2014

项目学科： 地质学

项目作者： 魏文学

作者单位： 中国科学院亚热带农业生态研究所

项目金额： 308万元

中文摘要： 氧化亚氮是一种重要温室气体，是21世纪最重要的消耗平流层臭氧的化合物。稻田重要的N2O排放源。本研究针对稻田排放N2O的三个关键过程（包括淹水-落干、肥料施用和水稻生长），通过根箱栽培、室内模拟和长期定位试验相结合，采用宏基因组学、转录组学、基因芯片和稳定性同位素核酸标记等先进技术，系统研究水稻土淹水-落干过程N2O产生、转化与释放的平衡机制、关键功能微生物驱动机理以及关键调控因子；揭示水稻根际和非根际土壤中硝化与反硝化微生物组成、丰度和活性差异与氮素转化和N2O释放的耦合关系；探讨长期施肥对水稻土氮素循环微生物活性表达组成和表达丰度与氮肥转化以及N2O排放特征的内在联系机理。从而系统揭示驱动稻田N2O排放的调控机制和关键微生物作用机理。本项研究的成果以及研究方法将对土壤过程与演变学科方向的发展有重要的推动作用，并为我国农田温室气体减排提供重要的科学依据。

中文关键词： 土壤氮循环;元基因组学;元转录组学;反硝化细菌;氨氧化细菌

英文摘要： Nitrous oxide is an important greenhouse gas and the most important compound causing depletion of stratosphere ozone in the 21 century. Agricultural soil is an important contributor to the global N2O emission. China is the largest rice producer with about 29 million hectares of rice paddy area, which is an important N2O source. It is critical to investigate the key mechanisms of functional microorganisms in driving N2O emission from paddy soils. In this project, the advanced techniques of metogenomics, transcroptomics, microarray, SIP will be employed to study microbial molecular mechanisms of nitrogen cycling. The driving mechanisms of N2O production and consumption of paddy soils during flooding-drying process will be investigated including the key factors and their roles in controlling N2O emission, the activity of nitrifiers and denitrifiers. The effect of rice root on nitrogen transformation will also be studied by investigating nitrifying and denitrifying communities in relation to N2O emission in rhizosphere. Furthermore, the impact of fertilization on nitrogen cycling and N2O emission will be explored through testing the community compositions and abundance of denitrifying genes and their transcripts. It will be investigate that the influence of soil fertility on N2O production and comsumption, and microbial driving mechanisms on nitrogen cycling. Conclusively, this project will systematically investigate the functions of the key microbial communities in driving N2O emission including production, consumption and emission in paddy soil, and the main environmental factors. The studies will be valuable in understanding controlling greenhouse gas emission in agricultural soils.

英文关键词： nitrogen cycling;metogenomics;transcroptomics;denitrifying bacteria;ammonia oxidizer