Yu Hao, He Zhili, Wang Aijie, Xie Jianping, Wu Liyou, Van Nostrand Joy D, Jin Decai, Shao Zhimin, Schadt Christopher W, Zhou Jizhong, Deng Ye
CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing, China.
College of Environmental Science and Engineering, Liaoning Technical University, Fuxin, China.
Appl Environ Microbiol. 2017 Dec 15;84(1). doi: 10.1128/AEM.01694-17. Print 2018 Jan 1.
Numerous studies have shown that the continuous increase of atmosphere CO concentrations may have profound effects on the forest ecosystem and its functions. However, little is known about the response of belowground soil microbial communities under elevated atmospheric CO (eCO) at different soil depth profiles in forest ecosystems. Here, we examined soil microbial communities at two soil depths (0 to 5 cm and 5 to 15 cm) after a 10-year eCO exposure using a high-throughput functional gene microarray (GeoChip). The results showed that eCO significantly shifted the compositions, including phylogenetic and functional gene structures, of soil microbial communities at both soil depths. Key functional genes, including those involved in carbon degradation and fixation, methane metabolism, denitrification, ammonification, and nitrogen fixation, were stimulated under eCO at both soil depths, although the stimulation effect of eCO on these functional markers was greater at the soil depth of 0 to 5 cm than of 5 to 15 cm. Moreover, a canonical correspondence analysis suggested that NO-N, total nitrogen (TN), total carbon (TC), and leaf litter were significantly correlated with the composition of the whole microbial community. This study revealed a positive feedback of eCO in forest soil microbial communities, which may provide new insight for a further understanding of forest ecosystem responses to global CO increases. The concentration of atmospheric carbon dioxide (CO) has continuously been increasing since the industrial revolution. Understanding the response of soil microbial communities to elevated atmospheric CO (eCO) is important for predicting the contribution of the forest ecosystem to global atmospheric change. This study analyzed the effect of eCO on microbial communities at two soil depths (0 to 5 cm and 5 to 15 cm) in a forest ecosystem. Our findings suggest that the compositional and functional structures of microbial communities shifted under eCO at both soil depths. More functional genes involved in carbon, nitrogen, and phosphorus cycling were stimulated under eCO at the soil depth of 0 to 5 cm than at the depth of 5 to 15 cm.
大量研究表明，大气中二氧化碳（CO₂）浓度的持续增加可能会对森林生态系统及其功能产生深远影响。然而，对于森林生态系统中不同土壤深度剖面在大气CO₂浓度升高（eCO₂）情况下地下土壤微生物群落的响应却知之甚少。在此，我们使用高通量功能基因微阵列（GeoChip），在经过10年的eCO₂暴露后，对两个土壤深度（0至5厘米和5至15厘米）的土壤微生物群落进行了检测。结果表明，eCO₂显著改变了两个土壤深度处土壤微生物群落的组成，包括系统发育和功能基因结构。关键功能基因，包括参与碳降解与固定、甲烷代谢、反硝化作用、氨化作用和固氮作用的基因，在两个土壤深度的eCO₂条件下均受到刺激，尽管eCO₂对这些功能标记的刺激作用在0至5厘米土壤深度处大于5至15厘米土壤深度处。此外，典范对应分析表明，硝态氮（NO₃-N）、总氮（TN）、总碳（TC）和落叶与整个微生物群落的组成显著相关。本研究揭示了eCO₂在森林土壤微生物群落中的正反馈作用，这可能为进一步理解森林生态系统对全球CO₂增加的响应提供新的见解。自工业革命以来，大气二氧化碳（CO₂）浓度一直在持续上升。了解土壤微生物群落对大气CO₂浓度升高（eCO₂）的响应对于预测森林生态系统对全球大气变化的贡献至关重要。本研究分析了eCO₂对森林生态系统中两个土壤深度（0至5厘米和5至15厘米）微生物群落的影响。我们的研究结果表明，在两个土壤深度的eCO₂条件下，微生物群落的组成和功能结构均发生了变化。与5至15厘米深度相比，在0至5厘米土壤深度的eCO₂条件下，更多参与碳、氮和磷循环的功能基因受到刺激。
