CHARACTERIZATION OF AQUATIC MACROPHYTES C OMMUNITIES (VASCULAR PLANTS, BRYOPHYTES, LICHEN) IN THE LIMOUSIN REGION AND HOW THEY ARE RELATED TO WATER-QUALITY (PURITY)

The authors analyze some communities of aquatic macrophytes living in running waters in the Limousin region : for slightly running waters, the Hyperico elodis - Potamogetonetum polygonifolii (Allorge 1922) Br .-Bl. and Tx. 1952. for the running waters (the Vienne and the Vezer e), the Callitricho hamulatae - Myriophylletum alterniflori (Steusloff , 1937) Weber-Oldecop 1967. The authors set up the matching between th e growing of these vegetal communities and various physico-chemical cr iteria which define the corresponding quality of waters. Beside, they enhance the original bioindicator part played by an aquatic lichen on pebble rocks, Dermatocarpon weberi, which concentrates significantly v arious pollution factors, among which heavy metals.