The toxic effects of Cu~(2+)、Zn~(2+)、Cd~(2+) on giant freshwater prawn juvenile

This study deals with the toxic effects and the accumulative action of Cu 2+ , Cd 2+ ,Zn 2+ on giant freshwater prawn (Macrobrachium rosenbergii) juvenile (L=0.88±0.12cm, W=8.7mg) and obtain 24h,48h,72h,96h LC 50 of Cu 2+ and Cd 2+ on giant freshwater prawn juvenile. The toxicity of Cd 2+ is greater than that of Cu 2+ . After juvenlies were cultured for 20 days in the test solution (at 0.01mg/L≤Cu 2+ ≤0.10mg/L, 0.002mg/L≤Cd 2+ ≤ 0.008 mg/L), and for 14 days (at 0.05mg/L≤Zn 2+ ≤0.85mg/L), the test prawns suffered different toxicity of Cu 2+ , Cd 2+ , Zn 2+ and growth and survival rates of juveniles decreased. Accumulative capacity (Ac, mg/kg) of Cu 2+ in the test juveniles body increased with rising concentration of Cu 2+ . Ac of Zn 2+ increases respectively with rising concentration (0.05mg/L-0.45mg/L). The accumulative multiple (At) of three heavy metals in the test juveniles body decreased with concentration rise.