Response of an Antarctic Lake Heterotrophic Community to High Dissolved Oxygen

• Main Authors: Mikell, Alfred T., Parker, Bruce C., Simmons, George M.
• Format: Text
• Language: English
• Published: 1984
• Subjects: General Microbial Ecology; Antarctic; Hoare; Lake Hoare; Hoare Lake; Antarc*; Antarctica
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC240055; http://www.ncbi.nlm.nih.gov/pubmed/16346535

The upper waters of Lake Hoare, Antarctica, contain dissolved oxygen at about three times the normal saturation (≥42 mg liter−1). The response of the heterotrophic plankton community to this high dissolved oxygen was evaluated by the criteria of CFU and d-[U-14C]glucose assimilated-respired. High dissolved oxygen was not inhibitory to d-[U-14C]glucose assimilation-respiration compared with normal atmospheric dissolved oxygen in Lake Hoare water. The d-[U-14C]glucose was assimilated and respired optimally at 12°C in Lake Hoare. The d-[U-14C]glucose assimilated-respired in the upper saturated atmospheric dissolved oxygen waters of Mountain Lake, Va., was inhibited in contrast to Lake Hoare (P < 0.05). CFU formation was inhibited in both lakes. CFU represent <1% of the fluorochrome-stained direct counts in Lake Hoare. Lake Hoare planktobacteria are smaller than the planktobacteria in Mountain Lake. ATP size fractionation revealed that 39% of the ATP biomass was <0.5 μm in Lake Hoare.