Ni、Zn对三疣梭子蟹幼体发育的慢性毒性(The Chronic Toxicity of Ni and Zn on Larval Development of Portunus trituberculatus)

为研究Ni、Zn对三疣梭子蟹幼体的毒性,进行了浓度为1/4至8倍渔业水质标准的Ni、Zn(Ni为0.05～0.4mg·L-1;Zn为0.1～0.8mg·L-1)对蟹幼体生长发育的毒性影响试验.1)Ni对蟹幼体生长发育的毒性影响:Ni浓度为1～8倍渔业水质标准时,蟹幼体混合存活率极显著低于对照组(p<0.01).Ni浓度为4倍渔业水质标准时,蟹幼体发育至Z4就全部死亡,8倍仅发育至Z2就全部死亡;4倍以上时,各期幼体存活率和阶段存活率均显著低于对照组(p<0.05或p<0.01).4倍以上时,蟹幼体发育的最短和最长时间及平均时间均显著高于对照组(p<0.05或p<0.01).这说明,进行三疣梭子蟹幼体培育,4倍以上Ni浓度为不适浓度,1～2倍为可行浓度,1/2倍以下为适宜浓度.2)Zn对蟹幼体生长发育的毒性影响结果发现,Zn浓度为8倍渔业水质标准时,蟹幼体混合存活率显著低于对照组(p<0.01),4倍以下时没有显著差异(p>0.05).4倍时蟹幼体仅发育至C1就全部死亡,8倍仅发育至Z2就全部死亡;4～8倍时各期幼体存活率和阶段存活率均极显著低于对照组(p<0.01).2倍以上时,蟹幼体发育的最短时间显著高于对照组(p<0.05);4倍以上时,蟹幼体发育的平均时间显著高于对照组(p<0.05).这说明,进行三疣梭子蟹幼体培育,4倍以上Zn浓度为不适浓度,2倍Zn浓度为可行浓度,1倍以下为适宜浓度.

The Chronic Toxicity of Ni and Zn on Larval Development of Portunus trituberculatus

Experiments have been conducted to test the toxic effect of Ni(0.05～0.4mg·L-1)and Zn(0.1～0.8mg·L-1)on the larval development of Portunus trituberculatus, these concentrations were between 1/4～8 times of the water quality standard for fisheries. 1)Ni. When the concentrations of Ni were 1～8 times of the water quality standard, they had extremely significant effect on the mixed survival rates compared with the control(p<0.01). When the Ni concentration was 4 times(0.2mg·L-1), the crab larvae developed only to the Z4 stage of zoea and when 8 times(0.4mg·L-1), the crab larvae developed only to the Z2 stage of zoea before they all die. Concentrations of above 4 times of the standard had significant effect on the larval survival rate and the stage survival rate compared with the control(p<0.05 or p<0.01), while the 8 times group had extremely significant effect compared with the control(p<0.01). Concentrations of above 4 times of the standard had significant effect on the shortest, longest and average duration of larval development compared with the control(p<0.05 or p<0.01). Accordingly, Ni concentrations of above 4 times of the standard were not suitable for the larval rearing of Portunus trituberculatus; Larvae can be reared with Ni concentrations of 1～2 times the standard; 1/2 times and below are the most appropriate concentration. 2)Zn. When the concentration of Zn was 8 times of the water quality standard, it had extremely significant effect on the mixed survival rates compared with the control(p<0.01), and the concentrations of below 4 times had no significant effect(p>0.05). When the Zn concentration was 4 times(0.4mg·L-1), the crab larvae developed only to the C1 stage of juvenile crab and it developed only to the Z2 stage of zoea when 8 times(0.8mg·L-1). 4～8 times groups had extremely significant effect on the larval survival rate and the stage survival rate compared with the control(p<0.01). Concentrations of above 2 times of the standard had significant effect on the shortest duration of larval development compared with the control(p<0.05), and had no significant effect on the longest duration(p>0.05). Concentrations of above 4 times of the standard had significant effect on the average duration of larval development compared with the control(p<0.05). Overall, Zn concentrations of above 4 times of the standard were not suitable for the larval rearing of Portunus trituberculatus. Larvae can be reared with Zn concentrations of 2 times the standard; 1 times and below are the most appropriate concentration.