ARSENIC CONCENTRATIONS IN SUCCESSIVE NEEDLE AGE CLASSES OF NORWAY SPRUCE (PICEA-ABIES [L] KARST)

Arsenic has been determined in needles of Norway spruce by neutron act ivation analysis. Trees from 8 sites grown under different soil and en vironmental situations have been sampled. Trees and needle age classes have been treated individually. Endogenous As concentrations in needl es < 100 ng/g have been detected. Concentrations increased linearly wi th the needle age class. This biodynamic behaviour is attributed tenta tively to a predominant foliar uptake. Concentrations at the various s ites differed by a factor of 7. No connection could be found between A s concentrations in needles and total As in the soil or pH of the soil . However, the strong correlation between the endogenous and the exoge nous concentrations, and differences of As concentrations in needles b etween different sites are thought to be due mainly to different input s of As from the atmosphere.