Article révisé par les pairs
| Résumé : | This paper presents results of bacterial biomass determination by epifluorescence microscopy after acridine orange staining and 3H-thymidine incorporation measurements in the river Meuse. Bacterial production is calculated from thymidine incorporation using an experimental conversion factor (0.5 1018 bacterial cells produced per mole of thymidine incorporated into macromolecules). Seasonal variations of bacterial biomass and production at two stations are presented. Biomass ranges between 0.05 mgC · 1−1 (in winter) and 0.8 mgC · 1−1 (in summer). The variations of bacterial production seem to be closely linked to those of primary production; values lower than 1 µgC · 1−1 · h−1 are found in winter and high values (> 5 µgC 1−1 · h −1) in summer. Longitudinal profiles in the Belgian course of the river show important increase of biomass and production from upstream to downstream. Bacterial growth yield (Y) has been determined (Y = 0.3) in order to calculate bacterial carbon uptake from bacterial production. |
