Journal of the Marine Biological Association of the UK



Research Article

The impact of two species of bioturbating shrimp (Callianassa subterranea and Upogebia deltaura) on sediment denitrification


Rebecca L.  Howe a1a2, Andrew P.  Rees a1c1 and Stephen  Widdicombe a1
a1 Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth, PL1 3DH, UK
a2 University of Plymouth, Drake's Circus, Plymouth, PL4 8AA, UK

Article author query
howe rl   [PubMed][Google Scholar] 
rees ap   [PubMed][Google Scholar] 
widdicombe s   [PubMed][Google Scholar] 

Abstract

In a benthic mesocosm experiment, the effects of two species of burrowing Thalassinidean shrimps (Callianassa subterranea and Upogebia deltaura) on rates of sediment denitrification were determined using the isotope pairing technique. Denitrification rate (Dtot) and coupled nitrification–denitrification (Dn) were shown to be significantly enhanced by the presence of U. deltaura by 2·9 and 3·3 times respectively, relative to control measurements. For U. deltaura the stimulation of the denitrification rate was found to be significantly related to the size of the animal (F=5·81, P=0·042). No deviation from the rates determined in control cores for either Dtot or Dn was observed for those cores inhabited by C. subterranea. The increase in Dtot with U. deltaura was considered to be the result of a combination of different factors, including; the direct extension of the sediment–water interface and an increase in oxygenation of the sediments and solute transport, as a result of the ventilating activities of the animal itself.

(Received November 4 2003)
(Accepted March 26 2004)


Correspondence:
c1 e-mail: apre@pml.ac.uk