Anabaena; Green algae; Algae--Growth; Plants--Habitat; Itasca, Lake (Minn.)
A relatively new field technique was employed to determine the growth of algae in natural waters. Anabaena sp. (Cyanophyta) and Dictyosphaerium sp. (Chlorophyta) were grown in separate membrane filter chambers situated in Lake Itasca and LaSalle Lagoon, a sewage effluent pond. Physical and chemical determinations before and after each two-week experiment were correlated with changes in algal biomass. Wet weight determinations of Anabaena were twice as great in the lake as in the sewage lagoon, while Dictyosphaerium growth was the same in both habitats. Nitrogen (nitrate and nitrite) was 0.09 • 0.2 mg/1 in the lagoon and from less than 0.01 • 0.04 in the lake. Orthophosphate in the lagoon was 6.5 • 8.2 mg/1 and in the lake was 0.05 - 0.18. Alkalinity, total hardness and turbidity measurements were higher in the lagoon, but both pH and temperature were the same. The greater growth of Anabaena in the lake could be due to the less turbid water, which permitted more light to reach the filter chamber. Similar Dictyosphaerium growth in each habitat cannot be explained on the basis of measurements made in this study, but it is possible to quantify algae growth in natural waters using membrane filters as a test for water quality.
Mason, C. P.
Unialgal Growth of Anabaena and Dictyosphaerium in Lake Itasca.
Journal of the Minnesota Academy of Science, Vol. 44 No.2, 12-13.
Retrieved from https://digitalcommons.morris.umn.edu/jmas/vol44/iss2/5