Optimal temperature conditions of Korean freshwater Cladoceran for development of standard toxicity test methods

Temperature is an important ambient factor affecting the physiology and metabolism of aquatic invertebrates. In this study, we studied about the survival, reproduction and growth effects of 4 different temperatures(16, 20, 24, ) in four Korean cladoceran, Daphnia sp., Daphnia obtusa, Moina macrocopa, Simocephalus vetulus and Daphnia magna as an international standard species. All 5 water flea tested showed that molting time, fecundity and intrinsic rate of natural increase(r) in high temperature condition were higher than those in lower temperature. On the other hand, lower survivals and longer time to start of offspring were showed in high temperature. Our results suggest that the optimal temperatures of Daphnia sp.,, Moina macrocopa and Simocephalus vetulus seem to be about except for Daphnia obtusa which as showed good survivals and reproductions in .