标题：Effects of Water Temperature and Silicate on the Winter Blooming Diatom Stephanodiscus hantzschii (Bacillariophyceae) Growing in Eutrophic Conditions in the Lower Han River, South Korea
摘要：We investigated the relationships between fluctuations in environmental factors and blooms of the diatom Stephanodiscus hantzschii by bi-weekly monitoring from February 2001 to February 2002 and from February 2004 to February 2005, in the eutrophic lower Han River (LHR), South Korea. With the exception of the summer rainy season when nutrients were lower, diatoms were abundant. Initial development of S. hantzschii populations (the most dominant diatom species in the LHR) started in late autumn, peaked in winter to early spring, and then gradually decreased in mid-spring. The peak of S. hantzschii abundance occurred at low water temperatures (approximately 5-10°C) and caused a significant decrease in silicate concentration, whereas other nutrients remained at eutrophic levels. The dynamics of S. hantzschii under the perennially eutrophic conditions of the LHR appears to be primarily affected by changes in water temperature, but growth of the diatom may be restricted by depletion of silicate.
