가막만 북서부해역 식물플랑크톤 군집의 시ㆍ공간적 분포 특성

A characteristics of the spatio-temporal distribution of phytoplankton community in northwestern Kamak bay, southern Korea

The observations on the spatio-temporal distributions of phytoplankton community were carried out in northwestern Kamak bay, southern Korea during four seasons from August 1997 to April 1998. A total of 54 species of phytoplankton belonged to 34 genera was identified. In northwestern Kamak bay seasonal succession in dominant species; Pseudo-nitzschia pungens in summer, Pn. Pungens, A sterionellopsis glacialis in autunm, Skeletonema costatum, A. glacialis, Leptocylindrus danicus in winter, and A. glacialis, S. costatum, Pn. Pungens in spring, had not come out clear, that is to say, the communities structure of phytoplankton in Kamak bay appeared to be simple species composition and it was occupied with diatoms all the year round. Phytoplankton standing crops fluctuated with an annual mean of 6.9x10⁵ cells/L between the lowest value of 5.9x10⁴cell/L in spring and the highest value of 2.5x10⁶cell/L by Pseudo-nitzchia pungens in summer. Densities of the phytoplankton cell number by the samples of northwestern Kamak bay ranged from 1.8x10⁴cell/L to 2.5x10⁶ cel1s/L with the mean value of 1.9x10⁵ cells/L in summer, from 10×10⁵ cells/L to 3.1x10⁵ cells/L with mean of 1.8x10⁵ cells/L in autumn, from 2.8x10⁵ cell/L to 6.6×10⁵ cell/L with mean 5.3×10⁵ cell/L in winter, and from 5.8x10⁴cell/L to 3.2×10⁵ cell/L with mean of 1.4×10⁵ cells/L in spring. That is to say, photo-plankton standing crops was high in summer and winter seasons, on the other hand low in spring and autumn seasons. Chlorophyll a concentration of surface layer fluctuated between 3.78 mg/m³in summer and 13.33 mg/m³ in winter. In northwestern Kamak bay seasonal fluctuation in chl-a concentration was not marked. Especially, chi-a concentration was high during a year.