Spatial and Temporal Variations of Environmental Factors and Phytoplankton Community in Andong Reservoir, Korea

doi:2005.20.4.333

Algae > Volume 20(4); 2005 > Article

Algae 2005;20(4): 333-343. doi: https://doi.org/10.4490/algae.2005.20.4.333

Jae Chung Park^*, Jung Won Park¹, Jong Dal Kim² and Jae-Ki Shin³

Andong Dam Office, Korea Water Resources Corporation(KOWACO), Andong 760-360,
¹Department of Biology, Kyungpook National University, Daegu 702-701,
²Northern Nakdong River Regional Water Quality Analysis Center, Korea Water Resources Corporation(KOWACO), Kumi 730-810 and
³Korea Institute of Water and Environment, Korea Water Resources Corporation(KOWACO), Taejon 305-730, Korea

ABSTRACT

Spatial and temporal variations of environmental factors and phytoplankton community were investigated in the three stations of Andong Reservoir in 1997 and 2003. The changes of physico-chemical water quality and phytoplanktonic biomass were higher in 2003 than that of 1997, due to rainfall difference. The concentration of total nitrogen (TN) and total phosphorus (TP) in the reservoir decreased, but total nitrogen fell relatively more between them. TN/TP ratio decreased from 109 to 90 showing no change at the downstream but a big decrease at the midand upstream. Predominant phylum of phytoplankton in Andong Reservoir were six genus that composed to Anabaena, Aphanizomenon and Microcystis of Cyanophyceae, Cosmarium and Scenedesmus of Chlorophyceae and Synedra of Bacillariophyceae, respectively. Among the observed phytoplankton, diatom Synedra occured as the maximum amount of 3,400 cells mL?1 even at the above 30°C. Green algae Scenedesmus observed along with Microcystis. It seemed to be compete with Microcystis during the high water temperature period. Although trophic state of Andong Reservoir was decreased, the standing crops of phytoplankton were increased. Moreover bluegreen algae, Aphanizomenon and Microcystis in the region of upstream to midstream and diatom, Synedra in the region of midstream to downstream were increased until to reach the algal bloom, respectively. It seemed necessary to attention the changes of blue-green algae Aphanizomenon, that has an ability of nitrogen fixation.

Key words: Andong Reservoir, Aphanizomenon, environmental factor, Microcystis, phytoplankton, Synedra, water