EFFECTS OF Cu2+ AND Zn2+ ON THE SURVIVAL, GROWTH AND NEONATE PRODUCTION OF DAPHNIOPSIS TIBETANA SARS

Effects of Cu2+ and Zn2+on the survival,growth and neonate production of Daphniopsis tibetana Sars were studied under (15 0.5)C and S=15.5 0.5.The results showed that the survival rate of D.tibetana,reared at ion activity of Cu2+=10-8.60-10-7.90 mol/L,had no significantly difference,but the growth rate at 10-8.60 mol/L was significantly higher than the others.When ion activity of Cu2+ was 10-8.60 and 10-8.13 mol/L,the intrinsic rate of increase (rm) was 0.2211/d and 0.2171/d,which was significantly higher than that of the control,and the rate of egg production of D.tibetana,reared at ion activity of Cu2+= 10-8.60-10-7.90 mol/L,was 0.9705-1.1742,which was significantly higher than that of the control.The survival rate and growth rate of D.tibetana which reared at ion activity of Zn2+= 10-7.51-10-6.82mol/L had no significantly difference.When ion activity of Zn2+ was 10-7.04-10-6.82 mol/L,the intrinsic rate of increase (rm ) was 0.2249/d-0.2296/d,which was significantly higher than that of the control.The rate of egg production of D.tibetana,reared at ion activity of Zn2+ =10-7.04-10-6.82mol/L was 1.0178 and 0.867,which was higher than other groups.Times of production of life of D.tibetana was 1.92-2.17,which was significantly higher than other groups when reared at 10-7.04-10-6.82 mol/L.In terms of results,we could conclude that the optimal ion activity of Cu2+and Zn2+ was 10-8.60-10-8.13 mol/L and =10-7.04-10-6.82mol/L,respectively.The mechanism of promoting growth,development and neonate production of D.tibetana was discussed in present paper.