The Unionid mussels (Mollusca, Bivalvia) of the Belgian upper river Meuse: an assessment of the impact of hydraulic works on the river water self-purification

peer reviewed ; In september 1983, the nine weirs regulating the flow of the river Meuse between Givet (France) and Namur (Belgium) were kept fully open for technical purposes. The water level therefore dropped, allowing the sampling of benthic organisms and the mapping of the different kinds of banks. For each bank type, the density of unionids mussels was measured. Silt and fine gravel bottoms are the preferred habitats of these mussels. In these natural habitats, the mean biomass is estimated at more than 1.8 tonnes/ha. In pebbles this value is near 1 tonne/ha whereas in the stony blocks an... Mehr ...