Deposition of Atmospheric Pollutants into a North German Forest Ecosystem

Abstract

In a North German forest stand a measuring station has been set up with the aim of supplying information on the impact of atmospheric pollutants. The results suggest that the wet deposition of heavy metals does not significantly differ from that in stands with forest decline in Southern Germany. Due to the windward location the total input is predominantly determined by dry deposition. The sulphate and chloride inputs are within the variation intervals found at other sites while the total nitrogen deposition ranges towards the upper limit. The gas concentrations show a pronounced dependence on the meteorological conditions. The long-term average values were found to be higher than at other typical sites, but they are for most gases below the recommended limits. Ozone, however, requires particular attention. The long-term mean clearly exceeds the guidelines. In general, the impact of gaseous pollutants on the forest primarily occurs during short-time episodes with high peak concentrations. There are distinct relationships between the concentrations of SO₂, or O₃, on the one hand and that of CO₂, on the other. In each case the fluxes are of opposite sign.