Seawater carbonate chemistry and growth and nutritional value of canopy-forming kelps

This dataset results from two, month-long global change laboratory experiments conducted in Sitka, Alaska from February 12 to March 18, 2020 (winter experiment) and August 15 to September 16, 2020 (summer experiment). These experiments were used to tease apart the effects of seasonal variation in light availability and nutrients on the response of three high-latitude kelp species (Macrocystis pyrifera, Hedophyllum nigripes, and Neoagarum fimbriatum) to pH and temperature. Experimental controls were designed to approximate current environmental conditions in Sitka Sound, and treatments were based on projected end-of-century scenarios of ocean acidification (OA) and warming (OW) for this region. At the end of the experiments, the investigators assessed the seasonal impact of OW and OA on kelp growth rates, thallus nitrogen content, and carbon acquisition strategy based on thallus δ13C values. Finally, to test whether kelp palatability was impacted by future warming and acidification, tissue of H. nigripes and N. fimbriatum grown during the experiments was used to perform feeding assays with a common kelp forest consumer.

本数据集源自两项为期一个月的全球变化实验室模拟实验，实验分别于2020年2月12日至3月18日（冬季实验）与2020年8月15日至9月16日（夏季实验）在阿拉斯加锡特卡（Sitka）开展。两项实验旨在厘清光照可获得性与营养盐的季节变化，对三种高纬度大型海藻——巨藻（Macrocystis pyrifera）、黑叶藻（Hedophyllum nigripes）以及新琼脂藻（Neoagarum fimbriatum）——响应pH与温度的调控效应。实验对照组的设置旨在模拟锡特卡湾（Sitka Sound）当前的环境条件，实验组则基于该区域至本世纪末的海洋酸化（Ocean Acidification, OA）与海洋增温（Ocean Warming, OW）预测情景设计。实验结束后，研究人员基于藻体的δ13C值，评估了海洋增温（OW）与海洋酸化（OA）对大型海藻生长速率、藻体氮含量以及碳获取策略的季节影响。最后，为验证未来海洋增温与酸化是否会影响大型海藻的适口性，研究人员利用实验期间培育的黑叶藻（H. nigripes）与新琼脂藻（N. fimbriatum）的组织样本，开展了针对一种常见海藻林消费者的摄食实验。