Stock Willem, Vanelslander Bart, Rüdiger Franziska, Sabbe Koen, Vyverman Wim, Karsten Ulf
Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Ghent, Belgium.
Institute of Biological Sciences, Applied Ecology and Phycology, University of Rostock, Rostock, Germany.
Front Microbiol. 2019 Jun 21;10:1395. doi: 10.3389/fmicb.2019.01395. eCollection 2019.
Coastal waters are expected to undergo severe warming in the coming decades. Very little is known about how diatoms, the dominant primary producers in these habitats, will cope with these changes. We investigated the thermal niche of , a widespread benthic marine diatom, using 24 strains collected over a wide latitudinal gradient. A multi-marker phylogeny in combination with a species delimitation approach shows that represents a (pseudo)cryptic species complex, and this is reflected in distinct growth response patterns in terms of optimum growth temperature, maximum growth rate, and thermal niche width. Strains from the same clade displayed a similar thermal response, suggesting niche conservation between closely related strains. Due to their lower maximum growth rate and smaller thermal niche width, we expect the polar species to be particularly sensitive to warming, and, in the absence of adaptation, to be replaced with species from lower latitudes.
预计在未来几十年里沿海水域将经历严重变暖。对于这些栖息地中占主导地位的初级生产者硅藻将如何应对这些变化，我们知之甚少。我们利用在广泛的纬度梯度上收集的24个菌株，研究了一种广泛分布的底栖海洋硅藻的热生态位。多标记系统发育与物种界定方法相结合表明，该硅藻代表一个（假）隐存种复合体，这在最佳生长温度、最大生长速率和热生态位宽度方面的不同生长反应模式中得到体现。来自同一进化枝的菌株表现出相似的热反应，表明亲缘关系较近的菌株之间存在生态位保守性。由于极地物种的最大生长速率较低且热生态位宽度较小，我们预计它们对变暖特别敏感，并且在没有适应的情况下，将被来自低纬度的物种所取代。
