Digging deeper to find unique microbial communities: The strong effect of depth on the structure of bacterial and archaeal communities in soil
Digging deeper to find unique microbial communities: The strong effect of depth on the structure of bacterial and archaeal communities in soil
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DOI：
10.1016/j.soilbio.2012.03.011
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发表时间：
2012-07-01
影响因子：
9.7
通讯作者：
Fierer, Noah
中科院分区：
文献类型：
--
作者：
Eilers, Kathryn G.;Debenport, Spencer;Fierer, Noah
微生物存在于整个土壤剖面中，生活在次表层的微生物可能在养分循环和土壤形成中发挥关键作用。然而，微生物在土壤剖面中的分布仍然知之甚少，因为大多数研究只关注那些在近地表层位发现的群落。在这里，我们研究了土壤剖面内微生物群落结构的变化，这些变化是否在不同景观位置的土壤中相似，以及个体土壤深度剖面内的群落水平变化如何与来自广泛生物群落的表层土壤的变化进行比较。我们通过位于美国科罗拉多州森林山地流域的九个土壤剖面，描述了细菌和古细菌群落组成和多样性随深度的变化。微生物群落组成通过采用捕获细菌和古细菌的引物组对16 S rRNA基因进行条形码焦磷酸测序来确定。相对微生物生物量和土壤碳浓度随深度呈指数下降，而土壤pH值增加，几乎所有的配置文件检查。细菌多样性通常最高的顶部10厘米的配置文件;多样性通常下降了20-40%，从表层到最深的视野采样。群落组成的显着影响土壤深度在所有配置文件，主要是由拟杆菌的相对丰度下降，深度和Verrucomicrobia之间的相对丰度的峰值10和50厘米。在九个坑的微生物群落组成是最可变的表面视野，在更深的土壤深度的社区是相对相似的，无论景观位置。当与54个先前分析过的表层土壤中收集的各种生物群落类型的微生物群落相比时，我们发现单个土坑内的变化与来自不同生物群落的表层土壤中的变化一样多，强调了土壤深度作为环境梯度结构土壤微生物群落的重要性。(C)2012爱思唯尔有限公司保留所有权利。
Microorganisms exist throughout the soil profile and those microorganisms living in sub-surface horizons likely play key roles in nutrient cycling and soil formation. However, the distributions of microbes through the soil profile remain poorly understood, as most studies focus only on those communities found in near-surface horizons. Here we examined how microbial community structure changes within soil profiles, whether these changes are similar across soils from different landscape positions, and how the community-level variation within individual soil depth profiles compares to the variation across surface soils from a wide range of biomes. We characterized changes in bacterial and archaeal community composition and diversity with depth through nine soil profiles located in a forested montane watershed in Colorado, USA. Microbial community composition was determined by barcoded pyrosequencing of the 16S rRNA gene employing a primer set that captures both bacteria and archaea. Relative microbial biomass and soil carbon concentrations decreased exponentially with depth while soil pH increased in nearly all of the profiles examined. Bacterial diversity was typically highest in the top 10 cm of the profile; diversity typically dropped by 20-40% from the surface horizons to the deepest horizons sampled. Community composition was significantly affected by soil depth in all profiles, driven primarily by a decline in the relative abundance of Bacteroidetes with depth and the peak in the relative abundance of Verrucomicrobia between 10 and 50 cm. Microbial community composition across the nine pits was most variable in the surface horizons; communities at deeper soil depths were relatively similar regardless of landscape position. When compared to the microbial communities from 54 previously-analyzed surface soils collected across a wide range of biome types, we found that there was as much variation within individual soil pits as across surface soils from different biomes, emphasizing the importance of soil depth as an environmental gradient structuring soil microbial communities. (C) 2012 Elsevier Ltd. All rights reserved.