进行了不同温度(10、14、17℃)和不同Cu(Ⅱ)质量浓度(7.40、32.63、56.58、193.94、300.48μg/L)的耦合作用对厚壳贻贝Mytilus coruscus D形幼虫生长和存活的急性毒性影响试验。结果表明:Cu(Ⅱ)胁迫96 h后,10、14℃试验组幼虫的存活率在Cu(Ⅱ)质量浓度为193.94、300.48μg/L时均显著降低(P〈0.05),17℃试验组幼虫的存活率在Cu(Ⅱ)质量浓度为56.58μg/L及以上时显著降低(P〈0.05);在温度为10、14、17℃时Cu(Ⅱ)胁迫的96 h半致死浓度(96 h LC50)分别为143.6、143.5、133.0μg/L,表明随着温度的升高LC50呈下降趋势;Cu(Ⅱ)胁迫96 h的生长试验结果显示,在10℃时,56.58μg/L质量浓度组的壳长相对增长率与对照组存在显著性差异(P〈0.05),14、17℃时,32.63、56.58μg/L质量浓度组的壳长相对增长率与对照组存在显著性差异(P〈0.05);在相同Cu(Ⅱ)浓度和不同水温胁迫下,17℃试验组幼虫壳长相对增长率显著高于10、14℃试验组(P〈0.05)。研究表明,Cu(Ⅱ)胁迫和温度的变化能影响厚壳贻贝D形幼虫的存活,且在较高的温度下幼虫对Cu(Ⅱ)胁迫更为敏感。
In this study,the combined effects of temperature( from 10 ℃ to 17 ℃) and copper( Ⅱ) concentrations ranging from 0( control) to 300. 48 μg / L on survival and growth of straight-hinge veliger larvae were investigated in mussel Mytilus curuscus. The results showed that the larval survival in 10 and 14 ℃ groups was found to be significantly reduced at copper concentrations of 193. 94 and 300. 48 μg / L in 96 h( P〈0. 05),while the larval survival in 17 ℃ group was shown to be significantly reduced at copper concentrations ≥ 56. 58 μg / L in 96 h,with LC50 of 143. 6 μg / L at 10 ℃,143. 5 at 14 ℃ and 133. 0 μg / L 17 ℃,indicating that the LC50 values was decreased with warming temperature. The 96 h growth trial revealed that significant difference in the relative growth rates in shell length was only observed between the copper treated group( 56. 58 μg / L) and the control group at 10℃( P〈0. 05). At 14 ℃ and 17 ℃,however,significant difference in the relative growth rates in shell length was found between the the copper treated groups( 32. 63 and 56. 58 μg / L) and the control in 96 h( P〈0. 05). Within the same copper concentration and various temperature,there was significant higher shell growth rate at 17 ℃ than at 10 ℃ and 14 ℃ in 96 h. The findings indicate that copper stress and changes in water temperature affect survival of the straight-hinge veliger larvae,and that larvae are more sensitive to copper stress in higher temperature.