title: Significance of bacterial biomass in the nutrition of a freshwater isopod (Lirceus sp.).
abstract: The quantitative significance of bacterial biomass in the nutrition of detritivores remains equivocal. We have used tritiated thymidine to specifically label stable macromolecules in natural assemblages of sediment-associated and detritus-associated bacteria. This material was presented to the isopod (Lirceus sp.) and incorporation of bacterial biomass measured. The isopod incorporated roughly 1 ng bacterial carbon (mg wet wt.)-1h-1from leaf discs and about 6 ng mg-1h-1from sediment. Calculation of grazing rate from changes in cell counts yields grazing rates from 2.3-17.9 ng C mg-1h-1. Even the maximum grazing rate, which is an overestimate of C assimilated, represents only 14.7% of C respired by the isopod.
authors.affiliation: Institute of Ecology and Department of Zoology, University of Georgia, 30602, Athens, GA, USA.
authors.forename: Stuart
authors.initials: S
authors.lastname: Findlay
authors.affiliation: Institute of Ecology and Department of Zoology, University of Georgia, 30602, Athens, GA, USA.
authors.forename: Judy L
authors.initials: JL
authors.lastname: Meyer
authors.affiliation: Institute of Ecology and Department of Zoology, University of Georgia, 30602, Athens, GA, USA.
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Smith