USE OF TRANSPLANTED MOSSES AND AUTOCHTHONOUS LIVERWORTS TO MONITOR TRACE-METALS IN ACIDIC AND NONACIDIC HEADWATER STREAMS (VOSGES MOUNTAINS, FRANCE)

Thirteen headwater streams situated in the Vosges Mountains (northeast ern France) have been studied for trace metal contamination (Al, Mn, P b, Cd) in relation to acidification. Assessment of metal concentration s has been performed using water analyses and metal content in transpl anted aquatic bryophytes. The streams studied ranged from acidic to ci rcumneutral. Aluminium, Mn and Pb concentrations in water increased si gnificantly with decreasing pH, whereas no relationship was observed b etween aqueous Cd concentrations and pH. The relation between metal co ntents in the moss and in the water varied markedly between metals. Al uminium and Pb levels in mosses reflect well the increasing concentrat ions of metals in water related to the pH whereas Mn in mosses does no t. The metal content of the autochthonous liverworts was different fro m those of the transplanted mosses which implies different conclusions about the contamination level of the water. Adaptation to different p H conditions leading to physiological and structural specificities cou ld explain the different ability of these two species to accumulate me tals in acid surroundings.