Department of Biological Science, Florida State University, 319 Stadium Drive, Tallahassee, Florida, 32306-4295, USA.
Plymouth Marine Laboratory, Prospect Place, Plymouth, Devon, PL1 3DH, UK.
J Phycol. 2020 Feb;56(1):85-96. doi: 10.1111/jpy.12922. Epub 2019 Nov 6.
Seaweeds are important components of near-shore ecosystems as primary producers, foundation species, and biogeochemical engineers. Seaweed communities are likely to alter under predicted climate change scenarios. We tested the physiological responses of three perennial, turf-building, intertidal rhodophytes, Mastocarpus stellatus, Osmundea pinnatifida, and the calcified Ellisolandia elongata, to elevated pCO over 6 weeks. Responses varied between these three species. E. elongata was strongly affected by high pCO , whereas non-calcified species were not. Elevated pCO did not induce consistent responses of photosynthesis and respiration across these three species. While baseline photophysiology differed significantly between species, we found few clear effects of elevated pCO on this aspect of macroalgal physiology. We found effects of within-species variation in elevated pCO response in M. stellatus, but not in the other species. Overall, our data confirm the sensitivity of calcified macroalgae to elevated pCO , but we found no evidence suggesting that elevated pCO conditions will have a strong positive or negative impact on photosynthetic parameters in non-calcified macroalgae.
海藻是近岸生态系统的重要组成部分，作为初级生产者、基础物种和生物地球化学工程师。在预测的气候变化情景下，海藻群落很可能会发生变化。我们测试了三种多年生、草坪状、潮间带红藻，Mastocarpus stellatus、Osmundea pinnatifida 和钙化的 Ellisolandia elongata，对 6 周高 pCO2 的生理反应。这三种物种的反应不同。E. elongata 受到高 pCO2 的强烈影响，而非钙化物种则没有。高 pCO2 并没有在这三种物种中引起光合作用和呼吸作用的一致反应。虽然基线光生理学在物种之间有显著差异，但我们发现高 pCO2 对大型藻类生理学这一方面几乎没有明显影响。我们发现 M. stellatus 中存在高 pCO2 反应的种内变异效应，但在其他物种中则没有。总的来说，我们的数据证实了钙化大型藻类对高 pCO2 的敏感性，但我们没有证据表明高 pCO2 条件会对非钙化大型藻类的光合作用参数产生强烈的积极或消极影响。
