Daphnia magna와 Ceriodaphnia dubia을 이용한 간극수 평가

Abstract

This study was conducted at 9 sites in the industrial watershed of the Namchun in Masan. The Namchun is the major stream of 8 streams down into Masan Bay. An amount of pollutants from the Namchun flows into Masan Bay. The bay is a typical enclosed bay, and is eutrophictaed and quite contaminated by pollutants such as nutrients and heavy metals. In order to estimate the toxicity of pore water extracted from bottom sediments we conducted two experiments on two daphnids, Daphnia magna and Ceriodaphnia dubia; (1) toxicity of pore water extracted by a centrifugation method (8000rpm), (2) toxicity of pore water extracted using an elutriate method. Toxicity on D. magna and C. dubia was higher in the sites 5-8 nearby industrial area than in other sites in both experiments. The values obtained from the centrifugation method were significantly correlated with the values from the elutriate method. Pore water extracted by the centrifugation method was more toxic than that by the elutriate method. Ceriodaphnia dubia was more sensitive than D. magna. This study suggests that D. magna and C. dubia might be used to assess sediment toxicity in the heavy polluted area and that pollutants from the Namchun may effect on the biology of organisms living in Masan Bay.