Long-term dynamics of freshwater red tide in shallow lake in central Japan

Abstract

Objective: The aim of this study is to clarify the long-term dynamics of the red tide occurring in Lake Kawaguchi.Methods: The measurement of environmental factors and water sampling were carried out monthly at a fixed station in Lake Kawaguchi's center basin from April 1993 to March 2004. On June 26, 1995, the horizontal distribution of Peridinium bipes was investigated using a plastic pipe, obtaining 0~1-m layers of water column samples at 68 locations across the entire lake.Results: P. bipes showed an explosive growth and formed a freshwater red tide in the early summer of 1995, when the nutrient level was higher than those in the other years, particularly the phosphate concentration in the surface layer. The dissolved total phosphorus (DTP) concentration was sufficient for P. bipes growth in that year. In the study of its horizontal distribution, P. bipes was found at all the locations. The numbers of cells per milliliter ranged from 67 to 5360, averaging 1094±987 cells/ml, with particularly high densities along the northern shore. Since then, P. bipes has annually averaged about 25 cells/ml in Lake Kawaguchi.Conclusion: We observed that the red tide caused by P. bipes correlates with a high DTP concentration in Lake Kawaguchi.

Biotic and Abiotic Factors Affecting the Population Dynamics of Ceratium hirundinella, Peridinium cinctum, and Peridiniopsis elpatiewskyi

“…Freshwater dinoflagellates of genera Ceratium, F. Schrank 1793; Peridinium, Ehrenberg 1830; and Peridiniopsis, Lemmermann 1904, are quite often components of biocenosis in many bodies all over the world and may even cause harmful blooms that negatively affect the water quality [1][2][3][4]. Some abilities of dinoflagellates are (i) tolerance to high irradiance [5]; (ii) migration in a water column to optimize photosynthesis and growth [5]; and (iii) toxin excretion [3] allow them to compete, grow, and dominate in the phytoplankton community.…”

“…Among genera of Peridinium and Peridiniopsis, Peridinium aciculiferum, Peridinium gatunense, Peridinium bipes, and Peridiniopsis minima are known as the causative agents of harmful bloom in freshwaters [1,2,4]. Ecology of Peridinium cinctum, (O.F.…”