Holothuroidea)

We evaluated the impact of ocean acidification on the early development of sea cucumber Apostichopus japonicus. The effect of pH-levels (pH 8.04, 7.85, 7.70 and 7.42) were tested on post-fertilization success, developmental (stage duration) and growth rates. Post-fertilization success decreased linearly with pH leading to a 6% decrease at pH 7.42 as compared to pH 8.1. The impact of pH on developmental time was stage-dependent: (1) stage duration increased linearly with decreasing pH in early-auricularia stage; (2) decreased linearly with decreasing pH in the mid-auricularia stage; but (3) pH decline had no effect on the late-auricularia stage. At the end of the experiment, the size of doliolaria larvae linearly increased with decreasing pH. In conclusion, a 0.62 unit decrease in pH had relatively small effects on A. japonicus early life-history compared to other echinoderms, leading to a maximum of 6% decrease in post-fertilization success and subtle effects on growth and development.

我们评估了海洋酸化对日本刺参（Apostichopus japonicus）早期发育的影响。测试了不同pH水平（pH 8.04、7.85、7.70和7.42）对受精后成功率、发育（阶段持续时间）及生长速率的影响。受精后成功率随pH值降低呈线性下降，与pH 8.1相比，pH 7.42时的成功率下降了6%。pH值对发育时间的影响具有阶段依赖性：（1）在耳状幼体早期阶段，阶段持续时间随pH值降低呈线性增加；（2）在耳状幼体中期阶段，阶段持续时间随pH值降低呈线性减少；但（3）pH值下降对耳状幼体晚期阶段无显著影响。实验结束时，桶形幼体的体型随pH值降低呈线性增大。综上，与其他棘皮动物相比，pH值下降0.62个单位对日本刺参早期生活史的影响相对较小，仅导致受精后成功率最大下降6%，且对生长发育的影响较为微弱。