Interactions of bacterio- and phyto-plankton in nutrient cycling within eutrophic Heywood Lake, Signy Island.

Abstract

In Heywood Lake, CO2 can become limiting to phytoplankton populations at certain periods of the production season. Bacterial breakdown of algal debris and extra-cellular products of photosynthesis is too slow to generate the necessary levels of carbon dioxide, so a 2nd extra-cellular DOC pool comprising small readily assimilable substrates was postulated. Evidence was found to support this. Bacteria have a beneficial effect on algal production in both N and P-depleted environments. Such mechanisms could explain the high production values recorded from enriched Antarctic lakes. -from Author