Photosynthesis, extracellular release and glycollic acid uptake by plankton: Fractionation studies

Summary

Size fractionation of lakewater samples from Lake Ontario and the Western Basin of Lake Erie showed that highest photosynthetic rates could be attributed to Rhodomonas sp. From a quantitative view the absolute amounts of soluble organic material released by photosynthetic algae in Lake Ontario and Lake Erie are relatively small (< 5%). Of the species present, extracellular release rates were highest in the phytoflagellates Rhodomonas sp., Uroglenopsis americana and the green alga Scenedesmus bijuga. Glycollic acid concentrations in Lake Erie and Lake Ontario were 58 μg/l and 24 μg/l, respectively. Uptake of glycollic acid was found to be correlated with bacteria.