Ocean acidification (OA), which is a major environmental change caused by increasing atmospheric CO₂, has considerable influences on marine phytoplankton. But few studies have investigated interactions of OA and seasonal changes in temperature and photoperiod on marine diatoms. In the present study, a marine diatom Skeletonema costatum was cultured under two different CO₂ levels (LC, 400 µatm; HC, 1000 µatm) and three different combinations of temperature and photoperiod length (8:16 L:D with 5 ^∘C, 12:12 L:D with 15 ^∘C, 16:8 L:D with 25 ^∘C), simulating different seasons in typical temperate oceans, to investigate the combined effects of these factors. The results showed that specific growth rate of S. costatum increased with increasing temperature and day length. However, OA showed contrasting effects on growth and photosynthesis under different combinations of temperature and day length: while positive effects of OA were observed under spring and autumn conditions, it significantly decreased growth (11 %) and photosynthesis (21 %) in winter. In addition, OA alleviated the negative effect of low temperature and short day length on the abundance of RbcL and key photosystem II (PSII) proteins (D1 and D2). These data indicated that future ocean acidification may show differential effects on diatoms in different clusters of other factors.

中文翻译：

---

肋骨骨骼藻对海水酸化以及光周期和温度的相互作用的生理响应

海洋酸化（OA）是由大气CO ₂含量增加引起的主要环境变化，对海洋浮游植物具有相当大的影响。但是很少有研究研究OA和海洋硅藻上温度和光周期的季节性变化的相互作用。在本研究中，海洋硅藻中肋骨条藻的混合物在两种不同的培养CO ₂水平（LC，400  μatm ; HC，1000  μatm）和温度和光周期长度的三种不同的组合（8:16 L：d 5  ^∘ Ç，12:12 L：d 15  ^∘ ç，16：8 L：d 25  ^∘ Ç），在典型的温带海洋模拟不同的季节，来调查这些因素的组合效应。结果表明，刺槐的比增长率随着温度和日长的增加而增加。然而，在不同温度和日长的组合下，OA对生长和光合作用表现出相反的影响：虽然在春季和秋季条件下观察到OA具有积极作用，但在冬季却显着降低了生长（11％）和光合作用（21％）。另外，OA减轻了低温和短日照长度对RbcL和关键光系统II（PSII）蛋白（D1和D2）的丰度的负面影响。这些数据表明，未来的海洋酸化可能对其他因素的不同集群中的硅藻显示出不同的影响。