Establishment of adequate conservation areas represents a challenging but crucial task in the conservation of genetic diversity and biological variability. Anthropogenic pressures on marine ecosystems and organisms are steadily increasing. Whether and to what extent these pressures influence marine genetic biodiversity is only starting to be revealed. Using 16S rRNA gene amplicon sequencing, we analysed the microbial community structure of 33 individuals of the habitat-forming glass sponge Vazella pourtalesii, as well as reference seawater, sediment, and biofilm samples. We assessed how two anthropogenic impacts, i.e. habitat destruction by trawling and artificial substrate provision (moorings made of composite plastic), correspond with in situ V. pourtalesii microbiome variability. In addition, we evaluated the role of two bottom fishery closures in preserving sponge-associated microbial diversity on the Scotian Shelf, Canada. Our results illustrate that V. pourtalesii sponges collected from pristine sites within fishery closures contained distinct and taxonomically largely novel microbial communities. At the trawled site we recorded significant quantitative differences in distinct microbial phyla, such as a reduction in Nitrospinae in sponges and environmental references. Individuals of V. pourtalesii growing on the mooring were significantly enriched in Bacteroidetes, Verrucomicrobia and Cyanobacteria in comparison to sponge individuals growing on the natural seabed. Due to a concomitant enrichment of these taxa in the mooring biofilm, we propose that biofilms on artificial substrates may 'prime' sponge-associated microbial communities when small sponges settle on such substrates. These observations likely have relevant management implications when considering the increase of artificial substrates in the marine environment, e.g., marine litter, off-shore wind parks, and petroleum platforms.

中文翻译：

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玻璃海绵Vazella pourtalesii对人为活动的响应

在保护遗传多样性和生物变异性方面，建立适当的保护区是一项具有挑战性但至关重要的任务。海洋生态系统和生物的人为压力正在稳步增加。这些压力是否影响海洋遗传生物多样性以及在何种程度上影响海洋遗传多样性，才刚刚开始被揭示。使用16S rRNA基因扩增子测序，我们分析了33个栖息地形成玻璃海绵Vazella pourtalesii个体的微生物群落结构，以及参考海水，沉积物和生物膜样品。我们评估了两种人为影响，即通过拖网破坏和提供人工基质（复合塑料制成的系泊设备）破坏栖息地，与原位V. pourtalesii微生物组变异性相对应。此外，我们评估了两个底部封闭渔场在保护加拿大斯科蒂大陆架上与海绵相关的微生物多样性中的作用。我们的结果表明，从渔业封闭区内原始地点收集的V. pourtalesii海绵含有独特的，在分类学上很大程度上新颖的微生物群落。在被拖网的地点，我们记录了不同微生物的门的定量差异很大，例如海绵中的亚硝基梭菌数量减少和环境参照物减少。与在天然海床上生长的海绵个体相比，在系泊物上生长的V. pourtalesii个体富含拟杆菌，Verrucomicrobia和蓝细菌。由于系泊生物膜中这些类群的同时富集，我们建议人工基质上的生物膜可能会“底涂” 当小海绵沉降在此类基质上时，与海绵相关的微生物群落。当考虑海洋环境中人造底物（例如，海洋垃圾，近海风电场和石油平台）的增加时，这些观察结果可能具有相关的管理意义。