Marine Biology

, Volume 121, Issue 2, pp 253–258

Bioturbation effects of the amphipod Corophium volutator on microbial nitrogen transformations in marine sediments

Authors

  • S. P. Pelegrí
    • Department of Microbial Ecology, Institute of Biological SciencesUniversity of Aarhus
  • T. H. Blackburn
    • Department of Microbial Ecology, Institute of Biological SciencesUniversity of Aarhus
Article

DOI: 10.1007/BF00346733

Cite this article as:
Pelegrí, S.P. & Blackburn, T.H. Marine Biology (1994) 121: 253. doi:10.1007/BF00346733

Abstract

Microcosms containing different densities of Corophium volutator, ranging from 0 to 6000 ind m-2, were incubated in a flow-through system. Benthic fluxes of CO2, O2, NO3- and NH4+ were measured regularly. Thirteen days after setup the microcosms were sacrificed and sediment characteristics, pore water NO3-, NH4+ and exchangeable NH4+ concentrations, and potential nitrification activity were measured. The presence of C. volutator increased overall mineralization processes due to burrow construction and irrigation. The amphipods increased the ratio ΣCO2/O2 fluxes from 0.73 to 0.86 in microcosms inhabited by 0 and 6000 ind m-2, respectively. Burrow ventilation removed NH4+ from the sediment, which was nitrified in the oxic layer and transported NO3- to the burrow sediment, where denitrification potential was enhanced. Nitrification and total denitrification rates (denitrification of NO3- coming from the overlying water and of NO3- generated within the sediment) were calculated and discussed. Bioturbation by C. volutator increased both nitrification and denitrification, but denitrification was stimulated more than nitrification. Denitrification of NO3- coming from the overlying water was stimulated 1.2- and 1.7-fold in microcosms containing 3000 and 6000 ind m-2 relative to control microcosms. The presence of C. volutator (6000 ind m-2) stimulated nitrogen removal from the system, as dinitrogen, 1.5-fold relative to non-bioturbated microcosms. C. volutator individuals used in our study were collected from Norsminde Fjord, Denmark, in 1990.

Copyright information

© Springer-Verlag 1994