Les microhabitats aquatiques des rives d'un grand coursd'eau: Approche faunistique

Abstract

The sampling of the submerged banks of the Rhône, upstream from Lyon, provided a faunistic approach that was new for the lotic environment. The banks are precisely defined: the explored zone corresponding with the upper fringe of the submerged bank. A complex mosaic of microhabitats forms the bank and a non-exhaustive list is proposed. A description of the sampling techniques for each microhabitat is provided. Finally a correspondence analysis on a matrix of 35 surveys × 80 taxa shows that the microhabitats shelter faunistic communities that are effectively different and characterised by three environments of erosion, sedimentation and vegetation. The a priori definition of the microhabitats is therefore validated by the distribution of the macroinvertebrates. Several examples are given of invertebrates that are characteristic of the different microhabitats: Leptoceridae (Trichoptera) in the eroding microhabitat, Hydropsyche sp. in the plant roots, and oligochaetes in the sedimenting microhabitat. © Masson, 1986.