【摘要】 以麦穗鱼(Pseudorasbora parva)为试验材料,研究了在一定环境条件下锌离子的胁迫对溴氰菊酯急性毒性的影响。结果表明,水温为(28.5±0.5)℃时,锌离子对麦穗鱼24~96h的LC50值为3.2~13.4mg/L,溴氰菊酯对麦穗鱼24~96h的LC50值为7.2~13.4μg/L;而水温为(15.5±0.5)℃时,锌离子对麦穗鱼24~96h的LC50值为18.0mg/L以上,溴氰菊酯对麦穗鱼24~96h的LC50值为5.6~10.0μg/L。水温的升高将明显地提高锌离子对鱼类的急性毒性,并降低溴氰菊酯对鱼类的急性毒性。研究同时发现,锌离子在酸性水质中对溴氰菊酯的急性毒性有增强的作用,且这种作用效果随着水温和锌离子质量浓度的上升而更为显著。但在中性及碱性水体中的效果不明显。在急性毒性试验96h后,锌离子在中、酸性水质中的质量浓度比较稳定,在碱性水质中有一部分损失,表明水中重金属的质量浓度变化比较稳定,主要受水质pH值影响,与温度无关。而溴氰菊酯的质量浓度下降明显,高温高pH值条件下的降解幅度尤为显著,说明水中溴氰菊酯的降解主要受水质pH值与温度的影响。研究显示,锌离子在一定条件下可增强溴氰菊酯的毒性作用,必须在实际生产中注意其联合污染效应。更多还原

【Abstract】 This paper is concerned with our study on the acute toxicity caused by the deltamethrin under zinc ion stress.Our study findings indicate that when the tested water was at the temperature of(28.5±0.5)℃,the value of 24-96 h LC50 of zinc ion vs Deltamethrin to Pseudorasbora parva proved to be 3.2-13.4 mg/L and 7.2-13.4 μg/L.However,when the tested water was at the temperature of(15.5±0.5)℃,the same zinc ion and Deltamethrin to Pseudorasbora parva proved over 18.0 mg/L and 5.6-10.0 μg/L respectively.Therefore,it seemed that high water temperatures may contribute to the increase of the acute toxicity of zinc ion to fish and reduction of the toxicity of deltamethrin.Our experimental results have also shown that,in acid water,zinc ion was likely to raise the acute toxicity of deltamethrin to fish with the increase of water temperature and that of the concentration of zinc ion.However,such effects were not found in the alkalescent and neutrality water.After a 96 hours’ test,the concentration of zinc ion in the acid and neutral water still refused to reveal remarkable change compared with the beginning stage of the test beginning.Nevertheless,the concentration of zinc ion could be made lower in the alkalescent water.In addition,the concentration of heavy metals,such as zinc ion,can be made changed with pH of water,though no direct relation was found with the water temperature.At the same time,the concentration of deltamethrin tended to remain lower even with the increase of temperature and pH of water,which may have something to do with the temperature and change of the pH value of water.It is for this reason that attention should be paid to the control of the comprehensive pollution effects caused by zinc ion and deltamethrin.更多还原