HETEROTROPHIC UTILIZATION OF ACETATE AND GLUCOSE IN SWARTVLEI, SOUTH AFRICA

Abstract

The utilization of dissolved organic compounds in Swartvlei was measured by the addition of single concentrations of ¹⁴C-labelled acetate and glucose to water samples, The results indicated acetate uptake was greatest in the aerobic zone while glucose was predominantly utilized in the anaerobic zone. With the exception of two months, integral glucose uptake was usually greater than the uptake of acetate. In August and September 1971 acetate was indicated as being utilized predominantly by flagellates and in December 1971 by dinoflagellates. During the remainder of the study, bacteria were assumed to be responsible for the uptake of acetate. The extensive weed beds which surround the upper reaches of Swartvlei may be a major source of acetate and glucose in the pelagic water column.