Dynamics in bacterioplankton production in a shallow, temperate lake (Lake Neusiedl, Austria)

Author(s): Bettina Reitner, Alois Herzig, Gerhard J. Herndl
Abstract: The seasonal dynamics in bacterioplankton abundance and production were studied at 3 characteristic stations (open water, large pond within the reed belt and within the reed Phragmites australis) in the shallow Lake Neusiedl, Austria, and related to phytoplankton primary production and dissolved organic carbon (DOC). DOC concentrations ranged from about 1 to 2.5 mmol l^-1 with humic DOC contributing between 40% during the winter and 55% during the summer. Phytoplankton production was highest in the pond within the reed belt, where the attenuation was lowest, reaching 110 mg C m^-2 d^-1 during a distinct phytoplankton bloom in August. Bacterial abundance ranged from 2 x 10⁶ cells ml^-1 during winter to about 10 x 10⁶ cells ml^-1 during summer. Bacterial production calculated by thymidine (TdR) and leucine (leu) incorporation, respectively, were in good agreement at the stations in the reed belt, but bacterial production based on leu incorporation was significantly lower than bacterial production based on TdR incorporation at the open water station. Based on a bacterial growth yield of 16% determined in an earlier study, bacterioplankton carbon demand was always at least 1 order of magnitude higher than carbon production of phytoplankton, indicating that bacterioplankton metabolism in Lake Neusiedl is heavily dependent on non-phytoplankton sources of DOC. The bacterial carbon demand (ranging from 225 to 870 mg C m^-2 d^-1 depending on the sampling site and substrate used) could be matched by the production of the reed P. australis amounting to 750 to 4510 mg C m^-2 d^-1. Since there is no major allochthonous organic matter input from other sources, this macrophyte production is obviously channeled to the pelagic food web via the bacterioplankton.
Organisation(s): Functional and Evolutionary Ecology
External organisation(s): Universität Wien, Biological Station Lake Neusiedl, Royal Netherlands Institute for Sea Research
Journal: Aquatic Microbial Ecology
Volume: 19
Pages: 245-254
No. of pages: 10
ISSN: 0948-3055
DOI: https://doi.org/10.3354/ame019245
Publication date: 10-1999
Peer reviewed: Yes
Austrian Fields of Science 2012: 106020 Limnology
Keywords
ASJC Scopus subject areas: Ecology, Evolution, Behavior and Systematics, Aquatic Science
Portal url: https://ucris.univie.ac.at/portal/en/publications/dynamics-in-bacterioplankton-production-in-a-shallow-temperate-lake-lake-neusiedl-austria(aee97c59-3e37-44fc-9d91-8da94751f04d).html