我国8个典型水稻土中产甲烷古菌群落组成的空间分异特征

Spatial shifts in methanogenic archaeal community composition in eight Chinese paddy soils

【目的】产甲烷古菌主导稻田甲烷生成,是稻田生态系统的模式微生物类群之一,具有重要的生态学意义。然而,水稻土产甲烷古菌群落组成的空间分异却鲜有报告。【方法】本研究沿20.55°N至47.43°N梯度,采集了我国不同纬度上8个典型水稻土,利用PCR-DGGE指纹图谱和系统发育树分析揭示不同地点水稻土中产甲烷古菌群落的组成;结合多个环境因子,利用生物信息学,典范对应分析(Canonical Correspondence Analysis,CCA)和维恩图(Venn diagram)明确产甲烷古菌的空间分异规律。【结果】研究发现p H值是驱动水稻土中产甲烷古菌群落组成分异的主要因子;此外,沿纬度梯度,8个地区的产甲烷古菌群落组成也呈现出规律性变化。【结论】本研究首次阐明了稻田中产甲烷古菌群落分布情况,并揭示其主要驱动因子。该认知不仅有助于我们更好地了解产甲烷古菌的生物地理学分布,还有助于从微生物学机制上阐明我国温度梯度带上有机质转化空间的差异。

[ Objective] The methanogenic archaea plays many ecological roles in paddy ecosystems such as the regulation of CH4 emissions. However, knowledge gaps exist about the mechanisms of their spatial shift in population. [ Methods] We collected 8 latitudinal paddy soil samples from 20. 55°N to 47.43°N in China, and studied their methanogenic archaeal community compositions by PCR-DGGE fingerprinting and phylogenetic analyses. Mechanism of spatial shift in community composition was unraveled by canonical correspondence analysis and Venn diagram. [ Results] Soil pH was one of the main environmental triggers to the composition of methanogenic archaea community in paddy soils. In addition, community composition shifted along latitudinal gradients. [ Conclusion ] It is the first report on biogeography of methanogenic archaeal community in arable soils and its environmental driving factors. The information would contribute to understanding spatial shifts in the transformation of organic matters along Chinese latitudinal gradient.