Ilicic Doris, Woodhouse Jason, Karsten Ulf, Zimmermann Jonas, Wichard Thomas, Quartino Maria Liliana, Campana Gabriela Laura, Livenets Alexandra, Van den Wyngaert Silke, Grossart Hans-Peter
Department of Experimental Limnology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Neuglobsow, Germany.
Institute of Biological Sciences, Applied Ecology and Phycology, University of Rostock, Rostock, Germany.
Front Microbiol. 2022 Mar 4;13:805694. doi: 10.3389/fmicb.2022.805694. eCollection 2022.
Aquatic ecosystems are frequently overlooked as fungal habitats, although there is increasing evidence that their diversity and ecological importance are greater than previously considered. Aquatic fungi are critical and abundant components of nutrient cycling and food web dynamics, e.g., exerting top-down control on phytoplankton communities and forming symbioses with many marine microorganisms. However, their relevance for microphytobenthic communities is almost unexplored. In the light of global warming, polar regions face extreme changes in abiotic factors with a severe impact on biodiversity and ecosystem functioning. Therefore, this study aimed to describe, for the first time, fungal diversity in Antarctic benthic habitats along the salinity gradient and to determine the co-occurrence of fungal parasites with their algal hosts, which were dominated by benthic diatoms. Our results reveal that Ascomycota and Chytridiomycota are the most abundant fungal taxa in these habitats. We show that also in Antarctic waters, salinity has a major impact on shaping not just fungal but rather the whole eukaryotic community composition, with a diversity of aquatic fungi increasing as salinity decreases. Moreover, we determined correlations between putative fungal parasites and potential benthic diatom hosts, highlighting the need for further systematic analysis of fungal diversity along with studies on taxonomy and ecological roles of Chytridiomycota.
水生生态系统常常被忽视，未被视作真菌的栖息地，尽管越来越多的证据表明，其多样性和生态重要性比之前认为的更大。水生真菌是营养物质循环和食物网动态的关键且丰富的组成部分，例如，对浮游植物群落施加自上而下的控制，并与许多海洋微生物形成共生关系。然而，它们与微型底栖植物群落的相关性几乎未被探索。鉴于全球变暖，极地地区面临非生物因素的极端变化，这对生物多样性和生态系统功能产生了严重影响。因此，本研究旨在首次描述沿盐度梯度的南极底栖生境中的真菌多样性，并确定真菌寄生虫与其以底栖硅藻为主的藻类宿主的共生情况。我们的结果表明，子囊菌门和壶菌门是这些生境中最丰富的真菌类群。我们发现，即使在南极水域，盐度不仅对真菌而且对整个真核生物群落组成的形成都有重大影响，随着盐度降低，水生真菌的多样性增加。此外，我们确定了假定的真菌寄生虫与潜在的底栖硅藻宿主之间的相关性，强调需要对真菌多样性进行进一步的系统分析，同时开展关于壶菌门的分类学和生态作用的研究。
