INDIVIDUAL TOXICITY AND JOINT TOXICITY OF COPPER LEAD AND ZINC IONC TO DAPHNIA MAGNA
Research on toxic effect of heavy metal combined pollution plays an importance role in ecological environment evaluation. The individual toxicity and the joint toxicity of Cu2+ 、Pb2 + and Zn2+ to Daphnia magna were investigated with a static test method. Results showed that the toxicity of Cu2+、Pb2+ and Zn2+ was degressive and the joint toxicity of Cu2 + - Zn2 + 、 Cu2 + - Pb2 + and Cu2 + - Pb2 + - Zn2 + was synergetic action, while Pb2 + -Zn + was antagonistic action. Joint toxicity was affected by combined gradation of poisons but it had no relation with ratio of chemical and exposure time.