紫海胆人工育苗技术的研究

本文报道了紫海胆人工育苗、人工诱导变态的方法。紫海胆浮游幼虫可分为棱柱幼虫、二腕幼虫、四腕幼虫、六腕幼虫和八腕幼虫5个期，历时约11d，角毛藻是浮游幼虫合适的铒料。幼海胆则以摄食底栖硅藻为主。育苗1个月幼海胆最大壳径为1．5mm。透明的聚乙烯片是适合的附着材料。     

紫海胆生殖腺和棘壳中的金属元素

在生殖季节从大亚湾采集紫海胆Anthocidariscrassispina ,分离出生殖腺和棘壳 ,用ICP AES法测定其金属元素含量。结果表明 ,紫海胆生殖腺中含有Ca ,Mg ,Sr,Fe ,Mn等1 8种金属元素。这些元素几乎都同样在棘壳中存在 ,而且棘壳中的浓度比生殖腺的高出几十倍到几百倍。同时发现棘壳中金属元素的浓度比海水中的高很多 ,如Fe的浓度为海水的34万倍 ,Mn为 1 4.5万倍 ,说明紫海胆对海水中金属元素有很强的富集作用。结果还表明紫海胆生殖腺中金属元素的含量存在性别差异 ,雌性生殖腺中Zn含量是雄性生殖腺的 4倍 ,而雄性生殖腺中Mg的含量比雌性生殖腺高。以食品卫生标准来衡量 ,大亚湾紫海胆生殖腺金属元素含量完全符合国家标准GBn 2 38 84。如何开发和利用这一海产资源 ,值得深入研究。     

Toxic Effects of Cadmium on Fertilizing Capability of Spermatozoa, Dynamics of the First Cleavage and Pluteus Formation in the Sea Urchin Anthocidaris crassispina (Agassiz)

Effects of cadmium on the fertilizing capability of spermatozoa, dynamics of the first cleavage and pluteus formation in the sea urchin, Anthocidaris crassispina, were investigated. Exposure to cadmium concentrations of 0.32, 0.56, 1.0, 1.8, 3.2, 5.6 and 10.0 mg l⁻¹ for 30 min caused a significant adverse effect on the fertilizing capability of spermatozoa (EC₅₀=1.7 mg l⁻¹). For the first cleavage kinetics assay, eggs were pre-exposed to 0, 0.18, 0.32, 0.56, 1.0, 1.8, 3.2 and 5.6 mg l⁻¹ of cadmium for 30 min. Fresh sperms of fixed concentrations were then added to the eggs and the percentage of divided zygotes estimated. Concentration-dependent toxic effects on the dynamics of the first cleavage in A. crassispina were observed between 0.18 and 5.6 mg l⁻¹ cadmium. Calculation of EC₅₀ values by probit analysis at different stages of the first cleavage revealed that EC₅₀ values increased gradually from 0.37 mg l⁻¹ at the beginning to 2.24 mg l⁻¹ at the end of the cleavage process. Different larval classes (normal, abnormal and retarded plutei, preplutei, dead embryos/larvae) of A. crassispina obtained from eggs pre-treated with cadmium for 30 min and then exposed to cadmium throughout embryogenesis were also examined. The percentage of abnormal plutei was significantly higher than that of the control at 0.56 mg l⁻¹ cadmium and higher. The 48 h EC₅₀ calculated for the number of normal plutei was 1.5 mg l⁻¹. A χ²-test revealed significant changes in the distribution of proportions of different larval classes only at cadmium concentrations 1.8 mg l⁻¹. At 5.6 mg l⁻¹ of cadmium, small malformed plutei, and oval embryos with rudimentary skeleton, poorly differentiated intestines and no mouth (pre-pluteus stage) were observed. The relative sensitivity of various end points to cadmium is also compared and discussed.     

紫海胆人工育苗技术研究

于1999年进行两批次紫海胆(Anthocidariscrassispina)育苗试验,浮游幼体以螺旋藻粉 光合细菌和球等鞭金藻 螺旋藻粉的两组饵料进行培育,当幼体发育变态为后期八腕幼体并30%幼体管足从前庭腹合体伸出之后,以已培养底栖硅藻的塑料薄膜进行采苗。附着后的稚海胆经过3个多月培育,壳径达到3～5mm剥离到网箱中进行中间培育。本试验两批共培育出壳径为2～11mm的海胆苗105155个,探索出易于推广应用的紫海胆育苗工艺。     

几种经济类海胆生殖腺的研究进展

本文综合了国内外学者对虾夷马粪海胆、光棘球海胆、马粪海胆、紫海胆等几种经济海胆有关生殖腺方面的研究成果，并根据国外学者对绿球海胆和Psammechinus miliaris等的研究，提出了这方面今后的研究重点。     

闽南紫海胆生产性人工育苗技术

报道了1999年7月到2000年10月在福建省东山县鲍鱼增殖中心进行的紫海胆(Anthocidaris crassistpina)生产性人工育苗技术试验。受精卵孵化后经过11d的浮游阶段的培育，移入采苗池，经过80d稚海胆阶段的培育，出苗量1万-1．2万粒／m^3，个体壳径4—16mm，平均壳径7．7mm。     

Effects of low pCO2 conditions on sea urchin larval size

Ocean acidification results from an increase in the concentrations of atmospheric carbon dioxide (CO₂) impacts on marine calcifying species, which is predicted to become more pronounced in the future. By the end of this century, atmospheric pCO₂ levels will have doubled relative to the pre‐industrial levels of 280 ppm. However, the effects of pre‐industrial pCO₂ levels on marine organisms remain largely unknown. In this study, we investigated the effects of pre‐industrial pCO₂ conditions on the size of the pluteus larvae of sea urchins, which are known to be vulnerable to ocean acidification. The larval size of Hemicentrotus pulcherrimus significantly increased when reared at pre‐industrial pCO₂ level relative to the present one, and the size of Anthocidaris crassispina larvae decreased as the pCO₂ levels increased from the pre‐industrial level to the near future ones after 3 days' exposure. In this study, it is suggested that echinoid larvae responded to pre‐industrial pCO₂ levels. Ocean acidification may be affecting some sensitive marine calcifiers even at the present pCO₂ level.