School of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA.
Microb Ecol. 2021 Aug;82(2):429-441. doi: 10.1007/s00248-020-01651-1. Epub 2021 Jan 7.
Peatland microbial community composition varies with respect to a range of biological and physicochemical variables. While the extent of peat degradation (humification) has been linked to microbial community composition along vertical stratification gradients within peatland sites, across-site variations have been relatively unexplored. In this study, we compared microbial communities across ten pristine Sphagnum-containing peatlands in the Adirondack Mountains, NY, which represented three different peat types-humic fen peat, humic bog peat, and fibric bog peat. Using 16S amplicon sequencing and network correlation analysis, we demonstrate that microbial community composition is primarily linked to peat type, and that distinct taxa networks distinguish microbial communities in each type. Shotgun metagenomic sequencing of the active water table region (mesotelm) from two Sphagnum-dominated bogs-one with fibric peat and one with humic peat-revealed differences in primary carbon degradation pathways, with the fibric peat being dominated by carbohydrate metabolism and hydrogenotrophic methanogenesis, and the humic peat being dominated by aliphatic carbon metabolism and aceticlastic methanogenesis. Our results suggest that peat humification is a major factor driving microbial community dynamics across peatland ecosystems.
泥炭地微生物群落组成随一系列生物和物理化学变量而变化。虽然泥炭降解（腐殖化）的程度与泥炭地垂直分层梯度内的微生物群落组成有关，但站点间的变化相对较少被探索。在这项研究中，我们比较了纽约阿迪朗达克山脉的十个原始含泥炭藓泥炭地的微生物群落，这些泥炭地代表了三种不同的泥炭类型——腐殖质沼泽泥炭、腐殖质泥炭和纤维泥炭。使用 16S 扩增子测序和网络相关分析，我们表明微生物群落组成主要与泥炭类型有关，并且不同的分类网络区分了每种类型的微生物群落。对两个以泥炭藓为主的沼泽的活动地下水位区（mesotelm）进行的宏基因组测序——一个是纤维泥炭，另一个是腐殖质泥炭——揭示了主要碳降解途径的差异，纤维泥炭以碳水化合物代谢和氢营养型甲烷生成为主，腐殖质泥炭以脂肪碳代谢和乙酸营养型甲烷生成为主。我们的结果表明，泥炭腐殖化是驱动泥炭地生态系统中微生物群落动态的主要因素。
