Ocean acidification impacts spine integrity but not regenerative capacity of spines and tube feet in adult sea urchins

Increasing atmospheric carbon dioxide (CO2) has resulted in a change in seawater chemistry and lowering of pH, referred to as ocean acidification. Understanding how different organisms and processes respond to ocean acidification is vital to predict how marine ecosystems will be altered under future scenarios of continued environmental change. Regenerative processes involving biomineralization in marine calcifiers such as sea urchins are predicted to be especially vulnerable. In this study, the effect of ocean acidification on regeneration of external appendages (spines and tube feet) was investigated in the sea urchin Lytechinus variegatus exposed to ambient (546 µatm), intermediate (1027 µatm) and high (1841 µatm) partial pressure of CO2 (pCO2) for eight weeks. The rate of regeneration was maintained in spines and tube feet throughout two periods of amputation and regrowth under conditions of elevated pCO2. Increased expression of several biomineralization-related genes indicated mole...

大气二氧化碳（carbon dioxide, CO₂）浓度升高导致海水化学组成改变与pH值下降，该过程被称为海洋酸化（ocean acidification）。明晰不同生物类群与生态过程对海洋酸化的响应规律，对预测未来持续环境变化情景下海洋生态系统的演变方向至关重要。诸如海胆（sea urchins）这类海洋钙化生物（marine calcifiers）体内涉及生物矿化（biomineralization）的再生过程，被认为尤其易受海洋酸化影响。本研究以杂色海胆（Lytechinus variegatus）为实验材料，设置了环境对照（546 μatm）、中等pCO₂（1027 μatm）与高pCO₂（1841 μatm）三个梯度，将其暴露于对应条件下8周，探究海洋酸化对其外附肢（棘与管足）再生过程的影响。在升高的pCO₂环境中，历经两次截肢与再生周期后，海胆的棘与管足再生速率均保持稳定。多个与生物矿化相关的基因表达量上调，表明