King Nathan G, Moore Pippa J, Thorpe Jamie M, Smale Dan A
Marine Biological Association of the United Kingdom, The Laboratory, Plymouth, PL1 2PB, UK.
School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
Microb Ecol. 2023 May;85(4):1265-1275. doi: 10.1007/s00248-022-02038-0. Epub 2022 May 20.
Kelp species are distributed along ~ 25% of the world's coastlines and the forests they form represent some of the world's most productive and diverse ecosystems. Like other marine habitat-formers, the associated microbial community is fundamental for host and, in turn, wider ecosystem functioning. Given there are thousands of bacteria-host associations, determining which relationships are important remains a major challenge. We characterised the associated bacteria of two habitat-forming kelp species, Laminaria hyperborea and Saccharina latissima, from eight sites across a range of spatial scales (10 s of metres to 100 s of km) in the northeast Atlantic. We found no difference in diversity or community structure between the two kelps, but there was evidence of regional structuring (across 100 s km) and considerable variation between individuals (10 s of metres). Within sites, individuals shared few amplicon sequence variants (ASVs) and supported a very small proportion of diversity found across the wider study area. However, consistent characteristics between individuals were observed with individual host communities containing a small conserved "core" (8-11 ASVs comprising 25 and 32% of sample abundances for L. hyperborea and S. latissima, respectively). At a coarser taxonomic resolution, communities were dominated by four classes (Planctomycetes, Gammaproteobacteria, Alphaproteobacteria and Bacteroidia) that made up ~ 84% of sample abundances. Remaining taxa (47 classes) made up very little contribution to overall abundance but the majority of taxonomic diversity. Overall, our study demonstrates the consistent features of kelp bacterial communities across large spatial scales and environmental gradients and provides an ecologically meaningful baseline to track environmental change.
海带物种分布在全球约25%的海岸线上，它们形成的森林是世界上一些生产力最高、生物多样性最丰富的生态系统。与其他形成海洋栖息地的生物一样，相关的微生物群落对宿主至关重要，进而对更广泛的生态系统功能也至关重要。鉴于存在数千种细菌与宿主的关联，确定哪些关系重要仍然是一项重大挑战。我们对来自东北大西洋一系列空间尺度（数十米到数百公里）的八个地点的两种形成栖息地的海带物种——巨藻和海带的相关细菌进行了表征。我们发现这两种海带在多样性或群落结构上没有差异，但有证据表明存在区域结构（跨越数百公里），并且个体之间存在相当大的差异（数十米）。在各个地点内，个体共享的扩增子序列变体（ASV）很少，并且仅支持在更广泛研究区域中发现的多样性的很小一部分。然而，观察到个体之间存在一致的特征，单个宿主群落包含一个小的保守“核心”（分别由8 - 11个ASV组成，占巨藻和海带样本丰度的25%和32%）。在更粗略的分类分辨率下，群落主要由四个类群（浮霉菌门、γ-变形菌纲、α-变形菌纲和拟杆菌纲）主导，它们占样本丰度的约84%。其余的分类群（47个类群）对总体丰度的贡献非常小，但占分类多样性的大部分。总体而言，我们的研究展示了海带细菌群落在大空间尺度和环境梯度上的一致特征，并提供了一个具有生态意义的基线来跟踪环境变化。
