Abstract:
The passive dissolution of anthropogenically produced CO2 into the ocean system is reducing ocean pH and changing a suite of chemical equilibria, with negative consequences for some marine organisms, in particular those that bear calcium carbonate shells. Although our monitoring of these chemical changes has improved, we have not developed effective tools to translate observations, which are typically of the pH and carbonate saturation state, into ecologically relevant predictions of biological risks. One potential solution is to develop bioindicators: biological variables with a clear relationship to environmental risk factors that can be used for assessment and management. Thecosomatous pteropods are a group of pelagic shelled marine gastropods, whose biological responses to CO2 have been suggested as potential bioindicators of ocean acidification owing to their sensitivity to acidification in both the laboratory and the natural environment. Using five CO2 exposure experiments, occurring across four seasons and running for up to 15 days, we describe a consistent relationship between saturation state, shell transparency and duration of exposure, as well as identify a suite of genes that could be used for biological monitoring with further study. We clarify variations in thecosome responses due to seasonality, resolving prior uncertainties and demonstrating the range of their phenotypic plasticity. These biomarkers of acidification stress can be implemented into ecosystem models and monitoring programmes in regions where pteropods are found, whilst the approach will serve as an example for other regions on how to bridge the gap between point-based chemical monitoring and biologically relevant assessments of ecosystem health.
摘要:
人为产生的二氧化碳被动溶解到海洋系统中正在降低海洋pH值并改变一系列化学平衡,对一些海洋生物有负面影响,特别是那些带有碳酸钙壳的。尽管我们对这些化学变化的监测有所改善,我们还没有开发有效的工具来翻译观察,通常是pH和碳酸盐饱和状态,与生态相关的生物风险预测。一种潜在的解决方案是开发生物指标:与环境风险因素有明确关系的生物变量,可用于评估和管理。翼足类翼足类动物是一组中上层有壳的海洋腹足类动物,由于其在实验室和自然环境中对酸化的敏感性,其对CO2的生物反应被认为是海洋酸化的潜在生物指标。使用五个二氧化碳暴露实验,发生在四个季节,运行长达15天,我们描述了饱和状态之间的一致关系,外壳透明度和暴露持续时间,以及确定一套可用于生物监测和进一步研究的基因。我们澄清了由于季节性而导致的染色体反应的变化,解决先前的不确定性,并证明其表型可塑性的范围。这些酸化胁迫的生物标志物可以在发现翼足类的地区实施生态系统模型和监测计划,同时,该方法将为其他地区提供如何弥合基于点的化学监测与生态系统健康的生物相关评估之间的差距的范例。