关键词: 马粪海胆, 海水酸化, 胚胎, 早期发育

Abstract: In order to study the impact of seawater acidification on early development of sea urchin Hemicentrotus pulcherrimus, this paper took 2 methods of CO2-induced and HCl-induced to simulate seawater acidification. According to IPCC prediction, the experiment designed one nature seawater group (Control, nature seawater pH), 3 CO2 treatment groups (OA1-CO2, OA2-CO2 and OA3-CO2, ΔpH=-0.3, -0.4, -0.5 units, respectively), and 3 HCl treatment groups (OA1-HCl,OA2-HCl and OA3-HCl, ΔpH=-0.3,-0.4,-0.5 units, respectively). Results showed that: ① these 2 methods had no significant effect on fertilization rate (P>0.05). ② Compared with nature seawater group, the embryo swimming percentage of H. pulcherrimus in all groups were decreased, but that in OA1-CO2 and OA1-HCl treatment groups were decreased remarkably (P<0.05), while that in other treatment groups (OA2-CO2, OA3-CO2, OA2-HCl and OA3-HCl treatment groups) were decreased (P<0.01). ③ Meanwhile, CO2-induced and HCl- induced seawater acidification also affected four-arm pluteus survival rate of H. pulcherrimus. The larval survival rate in majority of treatment groups (except the OA1-HCl treatment group) was remarkably decreased (P<0.01). Compared to that of nature seawater group, the larval survival rate of OA1-HCl treatment group was decreased significantly (P<0.05). The survival rates of other groups were also remarkably reduced (P<0.01). ④ Under CO2-induced seawater acidification conditions, we found that symmetry structure of four-arm pluteus was lost with the increasing of seawater pH, while there was no significant structure change of four-arm pluteus reared in HCl treatment groups. All results demonstrated that in the near future seawater acidification has an important effect on early development of sea urchin H. pulcherrimus, especially the seawater acidification induced by CO2.

Key words: Hemicentrotus pulcherrimus, seawater acidification, embryo, early development