Microbial Abundances Predict Methane and Nitrous Oxide Fluxes from a Windrow Composting System.
Microbial Abundances Predict Methane and Nitrous Oxide Fluxes from a Windrow Composting System.
复制标题
微生物丰度可预测料堆堆肥系统中的甲烷和一氧化二氮通量
DOI：
10.3389/fmicb.2017.00409
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发表时间：
2017
影响因子：
5.2
通讯作者：
Zou J
中科院分区：
文献类型：
--
作者：
Li S;Song L;Gao X;Jin Y;Liu S;Shen Q;Zou J
粪肥堆肥是大气中甲烷（CH4）和氧化亚氮（N2O）的重要来源，这是两种强有力的温室气体。CH4和N2O的通量分别由堆肥中的产甲烷菌和氧化甲烷菌、硝化菌和反硝化菌介导，而这些特定的细菌官能团可能在堆肥过程中相互作用，影响CH4和N2O的排放。为了验证细菌功能基因丰度调节窗口堆肥系统温室气体通量的假设，采用室内法同时测量了CH4和N2O通量，并利用分子技术量化了CH4相关功能基因（mcrA和pmoA基因）和N2O相关功能基因（amoA、narG、nirK、nirS、norB和nosZ基因）的丰度。结果表明，堆中相互作用的理化参数的变化决定了细菌功能基因丰度的动态变化。CH4和N2O通量与细菌群落中特定组成基因的丰度相关。逐步回归统计选择堆温、mcrA和NH4+共同作为CH4通量的最佳预测因子，将nirK、nosZ和pmoA基因丰度整合的模型几乎可以完全解释窗口堆肥N2O通量的动态变化。模拟模型与水稻种植系统的实测数据进行了对比，结果表明该模型同样适用于预测CH4和N2O通量对大气CO2浓度升高和温度升高的响应。微生物丰度可作为当前碳氮生物地球化学模型的指标。
Manure composting is a significant source of atmospheric methane (CH4) and nitrous oxide (N2O) that are two potent greenhouse gases. The CH4 and N2O fluxes are mediated by methanogens and methanotrophs, nitrifying and denitrifying bacteria in composting manure, respectively, while these specific bacterial functional groups may interplay in CH4 and N2O emissions during manure composting. To test the hypothesis that bacterial functional gene abundances regulate greenhouse gas fluxes in windrow composting systems, CH4 and N2O fluxes were simultaneously measured using the chamber method, and molecular techniques were used to quantify the abundances of CH4-related functional genes (mcrA and pmoA genes) and N2O-related functional genes (amoA, narG, nirK, nirS, norB, and nosZ genes). The results indicate that changes in interacting physicochemical parameters in the pile shaped the dynamics of bacterial functional gene abundances. The CH4 and N2O fluxes were correlated with abundances of specific compositional genes in bacterial community. The stepwise regression statistics selected pile temperature, mcrA and NH4+ together as the best predictors for CH4 fluxes, and the model integrating nirK, nosZ with pmoA gene abundances can almost fully explain the dynamics of N2O fluxes over windrow composting. The simulated models were tested against measurements in paddy rice cropping systems, indicating that the models can also be applicable to predicting the response of CH4 and N2O fluxes to elevated atmospheric CO2 concentration and rising temperature. Microbial abundances could be included as indicators in the current carbon and nitrogen biogeochemical models.