Abstract

As a preliminary study, effects of environmetal pollutants on propagation of freshwater microalgae, Cryptomonas ovata and feeding rate of Corbicula leana were investigated at 20<TEX>${\pm}$</TEX>1<TEX>$^{\circ}C$</TEX>, over 20 days after treatment of pollutants, glucose, complex fertilizer and NH4Cl. Number of C. ovata in control group was increased from 38<TEX>${\times}$</TEX>104 cell/ml to 1.910<TEX>${\times}$</TEX>104 cell/ml after 20 days cultivation in Sorokin-Krauss medium. Increments of cell number in experimental groups treated with glucose, complex fertilizer and NH4Cl were higher than that of control group. The higher propagation rate of C.ovata was observed when 30 mg/l of glucose treated, 120 mg/l of complex fertilizer treated, and 4 mg/l of NH4Cl treated, compared with other concentrations in each pollutant treated group. The feeding rates of large size group of C. leana which fed with a living organism, C. ovata in each experimental group were higher than small size group, and slightly reduced with the increase of pollutant concentrations. The feeding rates were not significantly different between any concentrations of the pollutant, and among experimental groups treated with glucose, complex fertilizer and NH4Cl.