Comment prélever les sédiments en suspension dans les cours d’eau ?

Abstract

Measurement of suspended sediment is an important issue for river management. Suspended particles can be mineral or organic and of natural or artificial origin. They have different sizes that are often described by a median diameter. To quantify the concentrations of suspended particles or their composition, samples are taken at one or more points of the cross section. These samples can be either instantaneous or averaged over time, at a single point, or integrated over depth. The choice of sampling technique should be adapted to the size of the river, the purpose of the study and the available samplers. This article presents some characteristics of the samplers currently used in the Rhône watershed and raises the question of the harmonisation of practices for suspended solids sampling in rivers. This harmonisation is necessary in order to be able to compare and discuss the calculated suspended sediment fluxes in order to understand and manage them.

Keywords

• prélèvement
• échantillon
• suspension
• sédiment
• sampling
• sample