마산만 중형동물플랑크톤 군집의 시,공간적인 변동

Abstract

The seasonal variation of zooplankton communities was investigated in Masan Bay from April 2004 to February 2005 at 12 stations. The zooplankton community consisted of 54 taxa during the survey period. Mean abundance of total zooplankton ranged from 1,140(May)～30,973(Nov.)inds./m3 and annual mean abundance of total zooplankton was 12,181inds./m3. Copepods were the predominant constituent, wihich comprised 1.3～92.0%(mean 40.6%) of the total zooplankton abundance. Five taxa accounted for approximately 67% of the annual mean zooplankton abundance: Noctiluca. scintillans(28.3%), Acartia omorii(17.8%), Paracalanus indicus(10.6%), Oikopleura spp.(6.6%) and Penilia avirostris(4.1%). A red tide causative dinoflagellate N. scintillans dominated during the study season except winter. P. indicus dominated from summer to winter, A. omorii in winter, P. avirostris in summer, Oikopleura spp. in summer and fall. Moon jellyfish Aurelia aurita may lead to a sharp decrease of the copepoda abundance from March to November in Masan Bay. A chaetognatha, Sagitta enflata and copepods, Acarocalanus gibber, Canthocalanus paupur, Temora stylifera, Clausocalanus furcatus and Scolecithrix danae indicating species for Kuroshio warm current species, were appeared from August to November and occurred in the largest at all stations in October of the year. This inflowing Kuroshio warm current influence the environmental characteristics of the survey area. During the study period except October, zooplankton communities in Masan Bay showed typical characteristics of coastal-estuarine communities, which were dominated by few species, and abrupt seasonal variations in abundance.