Predicting how populations and communities of organisms will respond to anthropogenic change is of paramount concern in ecology today. For communities of microorganisms, however, these predictions remain challenging, primarily due to data limitations. Information about long‐term dynamics of host‐associated microbial communities, in particular, is lacking. In this study, we use well‐preserved and freshly collected samples of soft tissue from a marine bivalve host, Donax gouldii, at a single site to quantify the diversity and composition of its microbiome over a decadal timescale. Site‐level measurements of temperature, salinity and chlorophyll a allowed us to test how the microbiome of this species responded to two natural experiments: a seasonal increase in temperature and a phytoplankton bloom. Our results show that ethanol‐preserved tissue can provide high‐resolution information about temporal trends in compositions of host‐associated microbial communities. Specifically, we found that the richness of amplicon sequence variants (ASVs) associated with D.gouldii did not change significantly over time despite increases in water temperature (+1.6°C due to seasonal change) and chlorophyll a concentration (more than ninefold). The phylogenetic composition of the communities, on the other hand, varied significantly between all collection years, with only six ASVs persisting over our sampling period. Overall, these results suggest that the diversity of microbial taxa associated with D.gouldii has remained stable over time and in response to seasonal environmental change over the course of more than a decade, but such stability is underlain by substantial turnover in the composition of the microbiome.

中文翻译：

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海洋双壳类微生物组的十年规模稳定性和变化

当今生态学中，最重要的是预测生物种群和群落如何应对人为变化。然而，对于微生物群落，这些预测仍然具有挑战性，主要是由于数据限制。尤其缺乏有关宿主相关微生物群落长期动态的信息。在这项研究中，我们使用保存完好的，新鲜收集的来自海洋双壳类宿主Donax gouldii的软组织样本，在一个站点上量化了十年时间内其微生物组的多样性和组成。现场测量温度，盐度和叶绿素a让我们测试了该物种的微生物组对两个自然实验的反应：温度的季节性升高和浮游植物的开花。我们的结果表明，乙醇保存的组织可以提供有关宿主相关微生物群落组成的时间趋势的高分辨率信息。具体来说，我们发现与D相关的扩增子序列变体（ASV）丰富。蛏没有显著随着时间的推移，尽管水的温度（+ 1.6℃，由于季节的变化）的增加和叶绿素改变一个集中（超过九倍）。另一方面，在所有采集年之间，群落的系统发育组成差异很大，在我们的采样期间仅存有六个ASV。总体而言，这些结果表明与D相关的微生物分类群的多样性。古尔德氏菌在过去的十多年中一直保持稳定，并响应季节性的环境变化，但是这种稳定性由微生物组组成的大量营业额来支撑。