Algae. 1998; 13(3): 331-338.

Ecological Characteristics of Phytoplankton Community in the Mid-and Downstream of the Han River

Yong Jae Kim, Myung Woon Kim, Sang Jong Kim

Department of Biology, Daejin University, Department of Environmental Engineering, Daejin University, Department of Microbiology, Seoul National University

The ecological characteristics of phytoplankton community was investigated at five stations in the mid- and downstream of the Han River from December, 1995 to November, 1996. This study identified a total of 369 taxa which was composed of 125 genera, 345 species, 26 varieties and 3 forms. Standing crops were ranged from 2.0 x 10 super(5) ind./l to 1.7 x 10 super(7) ind./l during the investigation. The dominant species were 11 taxa including Stephanodiscus invisitatus and Stephanodiscus hantzschii f. tenuis. Of these, the first record on the dominant species were Nitzschia palea, N. amphibia, N. fonticola, Cymbella minuta var. silesiaca, Cyclotella pseudostelligera. Stephanodiscus invisitatus and S. hantzschii f. tenuis were main species at St. 1 and St. 3 from December, 1995 to July, 1996 and rapidly decreased in rainy season. Aulacoseira ambigua and A. granulata were main species from August, 1996. Nitzschia palea showed high standing crops at St. 4 and 5 from rainy season. Therefore, these stations were eutrophic states during the investigated seasons.

Keywords : dominant species, eutrophic state, Han River, phytoplankton