Abstract

Phytodetrital sedimentation, bacterial activity in sediments, and benthic macro- and meiofauna abundance were measured to calculate a carbon budget for pelagic-benthic coupling in Lake Erken. Bacterial activity in surficial sediment was limited by temperature in spring, although a significant correlation with the input of spring-bloom phytodetritus was noted. Population dynamics of benthic meiofauna during a period of increased food availability in spring were highly taxon-specific and closely correlated to feeding behavior. Abundances of ostracods and nematodes rapidly increased when phytodetritus became available in hypolimnetic water and surficial sediment, respectively. Considerable time lags (months) were found between phytodetritus deposition and population development of harpacticoid copepods and chydorids.Carbon budget calculations based on sedimentation data (traps) and surficial sediment C content showed that during spring between 1.1 and 7.2% of deposited phytodetritus is assimilated by benthic meiofauna, whereas the dominant macroinvertebrates, sedentary chironomids, assimilated between 2.4 and 6.0%. On average, between 1.9 and 12.4% of the deposited phytodetritus was mineralized by sediment bacteria. A significant negative correlation was found between abundances of benthic meiofauna and bacteria in the sediment. Chlorophyll a analysis of surficial sediment was a necessary, complementary tool to detect sedimentation that was not detected by the traditional, cylindric sediment traps.

Published in

Limnology and Oceanography
1996, Volume: 41, number: 4, pages: 636-647

SLU Authors

• Johnson, Richard

  • Department of Environmental Assessment, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Ecology


Publication identifier

DOI: https://doi.org/10.4319/lo.1996.41.4.0636

Permanent link to this page (URI)

https://res.slu.se/id/publ/88288