The response of two ecologically important Antarctic invertebrates (Sterechinus neumayeri and Parborlasia corrugatus) to reduced seawater pH: effects on fertilisation and embryonic development
The response of two ecologically important Antarctic invertebrates (Sterechinus neumayeri and Parborlasia corrugatus) to reduced seawater pH: effects on fertilisation and embryonic development
复制标题
DOI：
10.1007/s00227-010-1529-y
复制
发表时间：
2010-12-01
期刊：
影响因子：
2.4
通讯作者：
Barker, Mike F.
中科院分区：
文献类型：
--
作者：
Ericson, Jessica A.;Lamare, Miles D.;Barker, Mike F.
海洋酸化或海水pH值降低是由于大气中的二氧化碳被封存到海洋中造成的。本研究调查了现今pH值8.0，预测的海洋表面pH值为2100年和2300年（pH值7.7和pH值7.3，分别）和极端pH值（pH值7.0）对南极纽虫Parborlasia corrugatus和海胆Sterechinus neumayeri的受精和胚胎发生的影响。在一定的精子浓度范围内，皱皮侧耳的受精成功率不受pH值的影响。在S. neumayeri在pH7.0和7.3的海水中显著下降，但仅在低精子浓度下。海水pH值对卵的卵裂率没有影响。neumayeri，或受精后1天异常胚胎的比例。波纹对虾胚胎发生对pH值的变化也相对稳健，只有当海水pH值降至7.0时才能检测到显著影响。虽然受精和早期细胞分裂相对稳健，但后来的发育到原肠胚对pH值敏感。pH7.0至囊胚期，pH7.0和pH7.3至腔肠囊胚期，异常胚数显著高于pH7.0和pH7.3。我们的研究结果与其他海洋无脊椎动物物种的观察结果相似，在这些物种中，受精和早期胚胎发育通常对海水pH值降低很敏感，而较老的腔肠囊胚和原肠胚阶段则更敏感。我们也没有发现任何证据表明，南极物种受到更不利的影响，较低的海水pH值相比，非南极同行的调查结果。我们的结论是，在我们检查的两个物种中，不久的将来pH值的降低（每千个pH值单位降低0.3-0.5个pH值单位）可能不会对受精和早期胚胎发生产生显著影响，而预测的长期降低（每千个pH值单位降低0.7-0.77个pH值单位）可能会降低S的受精成功率。如果精子浓度低，可能会增加P. corrugatus在胚胎发育后期的异常。
Ocean acidification, or the lowering of seawater pH, is caused by sequestration of atmospheric CO2 into the oceans. This study investigated the effects of present-day pH 8.0, predicted ocean surface pH for the years 2100 and 2300 (pH 7.7 and pH 7.3, respectively) and an extreme pH (pH 7.0) on fertilisation and embryogenesis in the Antarctic nemertean worm Parborlasia corrugatus and sea urchin Sterechinus neumayeri. Fertilisation success was not affected by pH in P. corrugatus across a range of sperm concentrations. Fertilisation success in S. neumayeri declined significantly in pH 7.0 and 7.3 seawater, but only at a low sperm concentration. Seawater pH had no effect on the rate of egg cleavage in S. neumayeri, or the proportion of abnormal embryos 1-day post-fertilisation. P. corrugatus embryogenesis was also relatively robust to pH changes, with a significant effect detected only when the seawater pH was decreased to 7.0. While fertilisation and early cell division were relatively robust, later development through to the gastrula was sensitive to pH. In S. neumayeri, an effect of pH on development was evident by the gastrula stage, while there were significantly more abnormal P. corrugatus embryos in pH 7.0 up to the blastula stage, and in pH 7.0 and pH 7.3 at the coeloblastula stage. Our results are similar to the observations on other marine invertebrate species where fertilisation and early embryonic development are generally robust to lowered seawater pH, while the older coeloblastula and gastrula stages are more responsive. We also found no evidence to suggest that Antarctic species are more adversely affected by lower seawater pH compared with the findings for non-Antarctic counterparts. We conclude that in the two species we examined, near-future decreases in pH (decreases of a parts per thousand 0.3-0.5 pH units) may not have a significant effect on fertilisation and early embryogenesis, while predicted longer term decreases (decreases of a parts per thousand 0.7-0.77 pH units) could reduce fertilisation success in S. neumayeri if sperm concentrations are low and may increase abnormalities in P. corrugatus during later embryogenesis.