Seasonal Variations of phytoplankton Communities in the Vicinity of Thermal Power Plants (Boryung and Seochon)

Algae > Volume 12(2); 1997 > Article

Algae 1997;12(2): 105-115.

Jin Hwan Lee, Eun Ho Lee

Department of Biology, Sangmyung University

ABSTRACT

In order to investigate species composition, representative species, dominant species, standing crops of phytoplankton communities and chlorophyll a, the present study was carried out at 5 stations in the vicinity of Boryung and Seochon Thermal Power Plants, respectively, during the period from March to December 1992. 108 taxa of phytoplankton communities, representing 978 diatoms, 8 dinoflagellates and 2 silicoflagellates were identified in the vicinity of Boryung T/P, and 86 taxa were composed of 79 diatoms, 5 dinoflagellates and 2 silicoflagellates in Seochon T/P. The representative species due to frequency were Coscinodiscus asteromphalus, C. radiatus, Cylindrotheca closterium, Hemiaulus hauckii, Leptocylindrus danicus, paralia sulcata and Skeletonema costatum in Boryung T/P. and Asterionellopsis gracialis, C. closterium, L. danicus, P. sulcata, Rhizosolenia setigera and S. costatum in Seochon T/P. A diatom Skeletonema costatum was the most outstanding species in all sampling periods and the other dominant species were Paralia sulcata, Rhizosolenia hebetata F. semispina, R. setigera, Asterionellopsis gracialis, Pseudonitzschia pungens and Cylindrotheca closterium. Phytoplankton standing crops varied in months and stations ranged from 3.5 × 10 super(4) cells/l to 2.47 × 10 super(6) cells/l in Boryung T/P, and ranged from 7.4 × 10 super(4) cells/l to 9.6 × 10 super(5) cells/l in Seochon T/P. Fluctuations of chlorophyll a ranged from 1.72 mg/m super(3) to 3.54 mg/m super(3) in Boryung T/P and ranged from 2.28 mg/m super(3) to 4.32 mg/m super(3) in Seochon T/P. Chlorophyll a concentrations were influenced by phytoplankton standing crops in these areas. Phytoplankton standing crops and chlorophyll a in discharge stations of Boryung and Seochon T/P slightly increased more than those of Intake.

Key words: discharge, intake, phytoplankton communities, seasonal variations, thermal power plants