Data accompanying: Crustose coralline algae display sensitivity to near future global ocean change scenarios

Most research investigating how ocean warming and acidification will impact marine species has focused on visually dominant species, such as kelps and corals, while ignoring visually cryptic species such as crustose coralline algae (CCA). CCA are important keystone species that provide settlement cues for invertebrate larvae and can be highly sensitive to global ocean change. However, few studies have assessed how CCA respond to low emission scenarios or conditions. In a laboratory experiment, we examined the responses of temperate CCA assemblages to combined warming and acidification projected under low, medium, and high emissions. Net calcification and net photosynthesis significantly declined in all emissions scenarios, while significant reductions in relative growth rates and increases in percentage bleaching were observed in the highest emission scenario. The negative responses of CCA to both low and medium emissions suggest that they may be adversely impacted by combined warming and acidification by 2030 if current emissions are sustained. This will have far reaching consequences for commercially important invertebrates that rely on them to induce settlement of larvae. These findings highlight the need to take rapid action to preserve these critical keystone species and the valuable services they provide.

当前有关海洋增温与酸化对海洋物种影响的研究，多聚焦于视觉上占据优势的类群，如巨藻与珊瑚，却忽略了壳状珊瑚藻（crustose coralline algae, CCA）这类视觉隐蔽类群。壳状珊瑚藻是重要的关键物种，可为无脊椎动物幼体提供附着诱导信号，且对全球海洋环境变化极为敏感。然而，目前鲜有研究评估CCA对低排放情景下环境条件的响应。本研究通过室内受控实验，探究了温带CCA群落在低、中、高碳排放情景下预估的海洋增温与酸化复合胁迫的响应。所有碳排放情景下，CCA的净钙化速率与净光合速率均显著下降；而在高排放情景中，其相对生长速率显著降低，白化占比显著升高。CCA对低、中排放情景均表现出负面响应，这表明若当前碳排放水平持续，到2030年时，海洋增温与酸化的复合胁迫或将对其造成不利影响。这将对依赖此类藻类诱导幼体附着的经济类无脊椎动物造成深远影响。本研究结果凸显了需快速采取行动，以保护这些关键类群及其所提供的重要生态系统服务。