메조코슴 내 용존산소에 미치는 야광충의 영향 연구

Abstract

We manipulated enclosed ecosystems by adding towed Noctiluca scintillans organisms into experimental mesocosm to understand effect of bloomed N. scintillans on the concentration of dissolved oxygen (DO). Experimental design consisted of ambient water, control(three bags filled with ambient water) and experiment (three bags filled with ambient water and addition of fifty times natural zooplankton by tender towing with 200μm mesh sized net). Present study was designed to monitor effect of N. scintillans blooms on the DO concentration using enclosed polyethylene bags (220 liters) during two weeks. DO concentration in experimental bags varied between 4.00 and 5.56 mg L-1 which is very low when compared to the ambient (6.03 and 8.68 mg L-1) and control bags(5.20 and 7.32 mg L-1). Abundances of N. scintillans, representing from 52.0 to 86.0 % of total abundances, ranged from 6 to 109 inds. L-1 in ambient water, 35-489 inds. L-1 in control bags and 237-791 inds. L-1 in experimental bags. The high abundances of N. scintillans in experimental bags stemmed from the artificially enhanced addition from the beginning of the study. DO concentration showed negative relationship with N. scintillans abundances. High abundance of N. scintillans corresponded to the low concentration of DO, whereas low abundance of N. scintillans was coincided with the relatively high concentration of DO. These results i