Changing oceans represent a serious threat for a wide range of marine organisms, with severe cascading effects on ecosystems and their services. Sea urchins are particularly sensitive to decreased pH expected for the end of the century and their key ecological role in regulating community structure and functioning could be seriously compromised. An integrated approach of laboratory and field experiments has been implemented to investigate the effects of decreased pH on predator-prey interaction involving sea urchins and their predators. Our results suggest that under future Ocean Acidification scenarios adult sea urchins defence strategies, such as spine length, test robustness and oral plate thickness, could be compromised together with their survival chance to natural predators. Sea urchins represent the critical linkage between top-down and bottom-up processes along Mediterranean rocky reefs, and the cumulative impacts of global and local stressors could lead to a decline producing cascading effects on benthic ecosystems.

不断变化的海洋对各种海洋生物构成严重威胁，对生态系统及其服务产生严重的连锁影响。海胆对本世纪末预期的pH降低特别敏感，其在调节群落结构和功能方面的关键生态作用可能会受到严重损害。已经实施了实验室和野外实验的综合方法来研究pH值降低对海胆及其捕食者与捕食者-猎物相互作用的影响。我们的结果表明，在未来的海洋酸化情景下，成年海胆防御策略（例如脊柱长度，测试稳健性和口腔板厚度）可能会受到损害，并且对天然捕食者的生存机会不利。