Adaptive evolution in the coccolithophore Gephyrocapsa oceanica following 1,000 generations of selection under elevated CO 2
Adaptive evolution in the coccolithophore Gephyrocapsa oceanica following 1,000 generations of selection under elevated CO 2
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高CO 2 条件下颗石藻Gephyrocapsa oceanica经过1,000代选择后的适应性进化
DOI：
10.1111/gcb.14065
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发表时间：
2018
影响因子：
11.6
通讯作者：
Hutchins, David A.
中科院分区：
文献类型：
--
作者：
Tong, Shanying;Gao, Kunshan;Hutchins, David A.
颗石藻是重要的海洋初级生产者，不仅在光合作用方面，而且因为它们产生称为颗石的方解石板。与海水碳酸盐化学变化相关的持续海洋酸化可能会损害颗石藻的钙化和其他代谢功能。虽然短期海洋酸化对钙化和其他性质的影响已经在各种颗石藻物种中进行了研究，但长期适应性反应几乎没有记录，除了单一物种Emiliania huxleyi。在这里，我们研究了海洋酸化对另一种重要的生态球石藻物种Gephyrocapsa oceanica的影响，在高CO2条件下（1,000 μatm）生长了1,000代。相对于在环境CO2（400 μatm）下选择的种群，高CO2选择的种群表现出降低的生长速率和增强的颗粒有机碳（POC）和氮（PON）产量。在高CO2选择性细胞系中，颗粒无机碳（PIC）和PIC/POC比值在整个选择期间逐渐下降。当高CO2生长的种群被移回环境CO2条件下约10代时，所有这些性状变化都持续存在。研究结果表明，海洋酸化对一些颗石藻的钙化可能比之前基于短期研究预测的更严重，这可能对加速人为影响下的海洋碳循环产生重大影响。
Coccolithophores are important oceanic primary producers not only in terms of photosynthesis but also because they produce calcite plates called coccoliths. Ongoing ocean acidification associated with changing seawater carbonate chemistry may impair calcification and other metabolic functions in coccolithophores. While short‐term ocean acidification effects on calcification and other properties have been examined in a variety of coccolithophore species, long‐term adaptive responses have scarcely been documented, other than for the single speciesEmiliania huxleyi. Here, we investigated the effects of ocean acidification on another ecologically important coccolithophore species,Gephyrocapsa oceanica,following 1,000 generations of growth under elevated CO2conditions (1,000 μatm). High CO2‐selected populations exhibited reduced growth rates and enhanced particulate organic carbon (POC) and nitrogen (PON) production, relative to populations selected under ambient CO2(400 μatm). Particulate inorganic carbon (PIC) and PIC/POC ratios decreased progressively throughout the selection period in high CO2‐selected cell lines. All of these trait changes persisted when high CO2‐grown populations were moved back to ambient CO2conditions for about 10 generations. The results suggest that the calcification of some coccolithophores may be more heavily impaired by ocean acidification than previously predicted based on short‐term studies, with potentially large implications for the ocean's carbon cycle under accelerating anthropogenic influences.