Although negative responses of tropical calcifying organisms to ocean acidification have been widely reported, the modulating potential of irradiance combined with elevated pCO₂ has not been well studied. In this study, the interactive effects of elevated pCO₂ and irradiance availability on the physiology of calcifying macroalgae Halimeda cylindracea and Halimeda lacunalis were investigated using a fully factorial, 28-day aquaria coupling experiment. The results of the present study demonstrate that elevated pCO₂ negatively influences growth, photosynthesis, calcification and other physiological processes of both Halimeda species. However, these negative effects could be mitigated to some extent by increased irradiance availability. Specific growth rate (SGR), net calcification rates (G_net) and maximum quantum yield (F_v/F_m) decreased significantly by 6.84%–86.70%, 51.78%–62.29% and 2.37%–28.91% in elevated pCO₂ treatments. However, SGR, G_net and F_v/F_m increased by 3.39%–84.78%, 29.61%–40.68% and 1.68%–6.92% in high irradiance conditions, respectively. Chl-a in elevated pCO₂ treatments was 7.75%–61.25% lower than ambient pCO₂ conditions, while the carotenoid content increased by 12.12%–57.45% in low irradiance conditions from day 20–28. Malondialdehyde (MDA) content was higher in elevated pCO₂ treatments. However, there was also a two- to four-fold increase in proline content in elevated pCO₂ treatments. Tissue total organic carbon (TC_org) and nitrogen (TN) were positively correlated to CO₂ enrichment. The results of the current study suggested that elevated pCO₂ negatively influenced the physiological responses of Halimeda, while increased irradiance availability may enhance the metabolic performance in response to ocean acidification.

尽管已经广泛报道了热带钙化生物对海洋酸化的负面反应，但是辐照与增加的p CO ₂结合的调节潜力尚未得到很好的研究。在这项研究中，使用全因子，28天的水族箱耦合实验研究了升高的p CO ₂和辐照度对钙化大型藻类Halimeda cylindracea和Halimeda lacunalis生理的相互作用。本研究的结果表明，升高的p CO ₂会对两者的生长，光合作用，钙化和其他生理过程产生负面影响Halimeda种。但是，可以通过增加辐照度来减轻这些负面影响。在p CO ₂升高的情况下，比生长率（SGR），净钙化率（G _net）和最大量子产率（F _v / F _m）分别显着下降了6.84％–86.70％，51.78％–62.29％和2.37％–28.91％。治疗。然而，在高辐照条件下，SGR，G _net和F _v / F _m分别增加了3.39％–84.78％，29.61％–40.68％和1.68％–6.92％。Chl- a升高p CO ₂处理比环境p CO ₂条件低7.75％–61.25％，而从20-28天开始，在低辐照条件下，类胡萝卜素含量增加了12.12％–57.45％。丙二醛（MDA）含量在较高的p CO ₂处理中较高。但是，在升高的p CO ₂处理中，脯氨酸含量也增加了2到4倍。组织总有机碳（TC _org）和氮（TN）与CO ₂富集呈正相关。目前的研究结果表明，p CO ₂升高负面影响Halimeda的生理反应，同时增加辐照度可增强响应海洋酸化的代谢能力。