Calcification is widely thought to be an adaptation that reduces the impact of herbivory. Recent work has shown that ocean acidification may negatively impact calcification of marine organisms, including coralline red algae, which could theoretically increase the susceptibility of corallines to benthic grazers. By manipulating calcium carbonate content of three articulated coralline algal species, we demonstrated that calcification has a variable and species-specific effect on urchin grazing. For two species, Corallina vancouveriensis and Corallina officinalis var. chilensis, reductions in calcium carbonate content did not cause a significant increase in urchin grazing, raising questions about the benefit of calcification in these species. For Calliarthron tuberculosum, reduced calcium carbonate content caused an increase in urchin grazing rates but only after calcium carbonate had been reduced by more than 15%, suggesting that only dramatic shifts in calcification would make C. tuberculosum more susceptible to urchin grazing. We hypothesize that the herbivory-reducing benefits of calcification likely depend upon coralline thallus morphology. Negative impacts of ocean acidification on calcification in coralline algae may not necessarily increase herbivory rates.

人们普遍认为钙化是一种减少草食动物影响的适应方法。最近的研究表明，海洋酸化可能会对包括珊瑚红藻在内的海洋生物的钙化产生负面影响，从理论上讲，这可能会增加珊瑚对底栖放牧者的敏感性。通过控制三种铰接的珊瑚藻物种的碳酸钙含量，我们证明钙化对野孩子放牧具有可变的和物种特异性的影响。对于两个物种，Corallina vancouveriensis和Corallina officinalis var。智利，碳酸钙含量的减少并没有导致海胆放牧的显着增加，这引发了人们对这些物种钙化的益处的质疑。对于Calliarthron tuberculosum降低的碳酸钙含量会导致海胆放牧率增加，但仅在碳酸钙减少了15％以上之后，表明钙化的剧烈变化才会使C. tuberculosum对海胆放牧更敏感。我们假设钙化减少草食动物的好处可能取决于珊瑚th的形态。海洋酸化对珊瑚藻钙化的负面影响不一定会提高食草率。