An investigation of a bloom of the desmid Gonatozygon.

Abstract

We investigated a bloom of the desmid Gonatozygon aculeatum var. aculeatum in Walker's Lake, Chippeaw County, Michigan. A Pearson's correlation was used to determine the degree of correlation between substrate, temperature, pH, depth, and relative abundances of Gonatozygon, Bulbochaete, Oedogonium, and Oscillatoria in samples taken from Walker's Lake. No significant correlation affecting Gonatozygon distribution was found between the variables. Walker's Lake was limed in August, 1989. To determine the part that the liming played in the Gonatozygon bloom, we designed an experiment in which samples from Walker's Lake were acidified, and samples from an adjacent lake in which Gonatozygon was absent were limed. Only the Whitmarsh Lake treatment showed a significant difference from its control, the limed samples had a greater percent abundance of healthy Gonatozygon cells. The experimental results supported our hypothesis that liming positively affects Gonatozygon health, but did not support the hypothesis that acidification adversely affects Gonatozygon health.