Food availability modulates the combined effects of ocean acidification and warming on fish growth
Food availability modulates the combined effects of ocean acidification and warming on fish growth
复制标题
食物供应调节海洋酸化和气候变暖对鱼类生长的综合影响
DOI：
10.1038/s41598-020-58846-2
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发表时间：
2020-02-11
影响因子：
4.6
通讯作者：
Peck, Myron A.
中科院分区：
文献类型：
--
作者：
Cominassi, Louise;Moyano, Marta;Peck, Myron A.
当生物体无法随意进食时，它们可能更容易受到环境压力源的负面影响，例如海洋酸化和变暖（OAW）。我们在 15 或 20 摄氏度、常温或高 PCO2（650 与 1750 mu atm PCO2；pH = 8.1 或 7.6）下随意饲喂鲈鱼（Dicentrarchus labrax），并在 277（20 摄氏度）和 367（15 摄氏度）天后观察到 PCO2 对幼鱼的年龄尺寸没有明显影响。然后进行喂养试验，包括限制定量（25%随意）。在 15 摄氏度时，生长速率随日粮增加而增加，但不受 PCO2 的影响。在 20 摄氏度时，酸化和变暖作用相反，低饲喂水平增强了 PCO2 效应。生长差异不仅是食物摄入量减少的结果，还与消化效率的变化有关。 20°C 时，消化酶（淀粉酶、胰蛋白酶、碱性磷酸酶和氨肽酶 N）的比活性在 PCO2 水平较高时较低。我们的研究强调了将限制喂养纳入检查 OAW 的实验设计中的重要性，并表明迄今为止大多数研究中使用的随意喂养可能不适合检测生态意义的影响。
When organisms are unable to feed ad libitum they may be more susceptible to negative effects of environmental stressors such as ocean acidification and warming (OAW). We reared sea bass (Dicentrarchus labrax) at 15 or 20 degrees C and at ambient or high PCO2 (650 versus 1750 mu atm PCO2; pH = 8.1 or 7.6) at ad libitum feeding and observed no discernible effect of PCO2 on the size-at-age of juveniles after 277 (20 degrees C) and 367 (15 degrees C) days. Feeding trials were then conducted including a restricted ration (25% ad libitum). At 15 degrees C, growth rate increased with ration but was unaffected by PCO2. At 20 degrees C, acidification and warming acted antagonistically and low feeding level enhanced PCO2 effects. Differences in growth were not merely a consequence of lower food intake but also linked to changes in digestive efficiency. The specific activity of digestive enzymes (amylase, trypsin, phosphatase alkaline and aminopeptidase N) at 20 degrees C was lower at the higher PCO2 level. Our study highlights the importance of incorporating restricted feeding into experimental designs examining OAW and suggests that ad libitum feeding used in the majority of the studies to date may not have been suitable to detect impacts of ecological significance.