Die Umweltbeeinflussung des Nährstoffhaushaltes eines bodensauren Buchenwalds

Abstract

Data are presented concerning the rain input, the filtering action of the forest in respect to air impurities, the percolation output, the uptake and the changes in soil stores. The hydrogen ion balance shows the acidification pressure exerted on the soil and the contribution of SO2 (75%) and litter decomposation (25%). 85% of the hydrogen ion input is buffered by the mineral soil, as a consequence losses of Al, Mn, Ca, Mg and Na occur. The annual losses correspond to 0.1% of the clay and feldspar content of the uppermost 20 cm soil layer. There are indications that due to the losses Mg will become a growth limiting factor in the next decades. It is assumed that the features indications Aeh-and Ahe-horizons developed during the last decades as a consequence of acid rain. The nitrogen input from air covers 40% of the uptake and is of high ecological significance. From this input 50% are stored in the increment of the stand, 25% in the soil. Liming is recommended in order to compensate the soil acidification.