Evolutionary adaptation of natural phytoplankton populations to warming

预计全球变暖将改变整个生态系统的温度状况。在海洋中，海面温度升高将影响海洋生物，可能对生态系统功能和生物地球化学循环产生影响。我们目前对海洋变暖的生物学后果的理解主要是基于短期实验，而进化适应的潜力只是慢慢得到关注。快速繁殖的浮游生物，如浮游植物，特别容易通过进化适应对环境变化作出反应。研究浮游植物进化过程的少数实验室选择实验表明，适应可以减轻气候变化的负面影响。然而，在实验室中观察到的适应与自然种群的相关性仍有待解决。研究天然浮游植物种群进化适应的一个绝佳机会可以在瑞典沿海水域找到，在那里，核电站的冷却水排放导致了有充分记录的当地变暖制度。在这些沿海地区，常见的硅藻物种马里诺骨骼肌形成了当地有限的种群，基因型变化可以在沉积物中保存数十年。该项目旨在利用这些有希望的环境来评估两个独立的S. marinoi种群对变暖的进化适应的相关性，这两个种群在过去几十年里受到了类似的变暖影响。要可靠地预测生物对海洋变化的反应，对进化过程的深刻理解很可能是必不可少的，因此不仅对科学，而且对决策者和社会都具有关键意义。

Global warming is projected to alter temperature regimes across ecosystems. In the ocean, increased sea surface temperatures will affect marine organisms, with likely consequences for ecosystem functioning and biogeochemical cycles. Our present understanding of the biological consequences of ocean warming is primarily based on short-term experiments, while the potential for evolutionary adaptation is only slowly gaining attention. Fast reproducing planktonic organisms, such as phytoplankton, are particularly prone to respond to environmental change via evolutionary adaptation. The few laboratory selection experiments that have addressed evolutionary processes in phytoplankton suggest that adaptation can mitigate negative effects of climate change. However, the relevance of adaptation observed in the laboratory to natural populations remains to be resolved. One outstanding opportunity to investigate evolutionary adaptation in natural phytoplankton populations can be found in Swedish coastal waters where cooling water discharges from nuclear power plants have resulted in well documented local warming regimes. In these coastal areas the common diatom species Skeletonema marinoi forms locally restricted populations and genotypic changes can be followed over decades via resting stages preserved in the sediments. The proposed project aims to use these promising settings to assess the relevance of evolutionary adaptation to warming in two independent S. marinoi populations that have been similarly affected by warming over the last decades. A profound understanding of evolutionary processes will most likely be indispensable for reliably predicting biological responses to ocean change and is thus of pivotal relevance, not only to science, but also to policy makers and society.