식물플랑크톤의 성장과 광합성에 대한 benzo[a]pyrene의 영향

Abstract

We examined the impacts of anthropogenic pollutant (benzo[a]pyrene) onSkeletonemacostatum, Heterosigma akashiwo, Prorocentrum dentatum, P. minimum, Akashiwosanguinea ), which are dominant in Korean coastal water. After the 72 h exposure tobenzo[a]pyrene, the dramatic decrease in cell numbers was observed in the range of 1to 10 g L-1 for S. costatum, P. minimum, P. dentatum , whereas for A. sanguinea and H.akashiwo at the low concentrations 0.1 to 1 g L-1. Among the 5 phytoplankton species,the highest growth inhibition concentration (IC 50) was 6.20 g L-1 for P. minimum,followed by 2.14 g L-1 for P. dentatum , 1.68g L-1 for S. costatum, 0.74g L-1 for H.akashiwo , 0.10g L-1 for A. sanguinea . The five species exposed to the low concen-tration of 1 g L-1 were recovered after transferring to new media, but the speciesexposed to the high concentrations of 10 and 100 g L-1 were not recovered, with theexception of P. minimum . These results indicate that the thecate dinoflagellate P. mini-mum is most tolerant to the chemical and the athecate dinoflagellate A. sanguinea isnot. Generally, the cell -specific photosynthetic capacity of H. akashiwo exposed to thelow concentrations of 0.1 and 1 g L-1 was higher than that of the cells in the control,whereas the cells exposed to the high concentrations of 5 and 10 g L-1 showed thenegligible photosynthetic level by the first few days of the experiment. In the case ofthe cells exposed to the concentration of 5 g L-1, after 12 days of the experiment thephotosynthetic capacity was increased toward the end of the experiment. This indi-cates that H. akashiwo may utilize the benzo[a]pyrene as a carbon source for its growthwhen exposed to low concentrations. Results suggest that anthropogenic pollutantssuch as benzo[a]pyrene may have significant influence on the succession of phyto-plankton species composition and the primary production in coastal marine environ-ments.