Living Systems Institute, University of Exeter, Exeter, EX4 4QD, UK.
Biosciences, University of Exeter, Exeter, EX4 4QD, UK.
Sci Rep. 2024 Nov 21;14(1):28896. doi: 10.1038/s41598-024-77821-9.
The Arctic Ocean (AO) is changing at an unprecedented rate, with ongoing sea ice loss, warming and freshening impacting the extent and duration of primary productivity over summer months. Surface microbial eukaryotes are vulnerable to such changes, but basic knowledge of the spatial variability of surface communities is limited. Here, we sampled microbial eukaryotes in surface waters of the Beaufort Sea from four contrasting environments: the Canada Basin (open ocean), the Mackenzie Trough (river-influenced), the Nuvuk region (coastal) and the under-ice system of the Canada Basin. Microbial community structure and composition varied significantly among the systems, with the most phylogenetically diverse communities being found in the more coastal systems. Further analysis of environmental factors showed potential vulnerability to change in the most specialised community, which was found in the samples taken in water immediately beneath the sea ice, and where the community was distinguished by rare species. In the context of ongoing sea ice loss, specialised ice-associated microbial assemblages may transition towards more generalist assemblages, with implications for the eventual loss of biodiversity and associated ecosystem function in the Arctic Ocean.
北极海（AO）正在以前所未有的速度发生变化，持续的海冰损失、变暖以及淡水化影响了夏季初级生产力的范围和持续时间。表层微生物真核生物容易受到这些变化的影响，但对于表层群落的空间变异性的基本了解是有限的。在这里，我们从四个截然不同的环境中对波弗特海的表层水域中的微生物真核生物进行了采样：加拿大海盆（开阔海域）、麦肯齐海槽（河流影响）、努武克地区（沿海）和加拿大海盆的冰下系统。系统之间的微生物群落结构和组成存在显著差异，最具系统发育多样性的群落存在于更沿海的系统中。对环境因素的进一步分析表明，在最具专业化的群落中存在潜在的变化脆弱性，这些群落存在于海冰下的水样中，其特征是稀有物种。在持续的海冰损失的背景下，专门的冰附生微生物组合可能会向更具普遍性的组合过渡，这对北极海洋的生物多样性和相关生态系统功能的最终丧失产生影响。
