Distribution of nutrients and trace elements in annual rings of pine trees (Pinus silvestris) as an indicator of environmental changes

Summary

Annual rings of about 100-year-old pine trees (Pinus silvestris) from two locations of the Nürnberger Reichswald were investigated. According to the chronological distribution patterns, the elements can be divided into two groups: a) elements with decreasing concentration from the older to the younger wood: Ca, Mg, Mn, Zn, Al, Pb and Cd; b) elements with increasing concentration: K, P, S, Fe, Cu and Ni. These changes of the element uptake occur at both locations almost parallel and this could be the result of two superimposed tendencies: On the one hand, it indicates increasing immission of pollutants; accordingly for several elements increasing deposition can be observed. On the other hand, sulphur dioxide causes progressive acidification of the soil and the biosphere, followed by increasing washing out of elements. The industrial development, especially the emission of sulphur dioxide, is assumed to be the cause of at least part of these effects. According to our interpretation, sulphur seems to be the key-element for understanding both tendencies.