TRANSPORT OF TRACE ELEMENTS IN ECOSYSTEMS OF THE BÄRHALDE WATERSHED IN THE SOUTHERN BLACK FOREST

Abstract

Concentrations of trace elements and macroelements in rainfall, canopy drip, runoff and soil solution have been determined each week at 4 free-drained and 3 hydromorphic sites at an altitude of 1000-1300 m above sea level in the very humid, cool Black Forest. Among these elements, the turnover of Be, Cd, Cu and Pb are discussed in detail. Be had the lowest input and the highest output of these 4 elements. It was primarily mobilized in the mineral topsoil, and only a small amount was readsorbed by humic acids or subsoil or taken up by plants. Pb concentrations were highest in precipitation, but only about 5% of the input appeared in the output. Cd, Cu and Pb were all adsorbed by the humans and iron oxide accumulation horizons of podzols and Ockererde. Cu was adsorbed in all soils except podzols, and fixation of Cu was especially obvious in the Ockererde. Cd was not highly adsorbed in mineral soil. The recent increase in atmospheric input resulted in an enrichment and rise of turnover for Cd, Cu and Pb throughout the watershed.