Trace Metals and Radionuclides in Austrian Forest Ecosystems

Deposition of heavy metals may lead to long-term injuries/damages and to complete and irreversible degradation of soils in forest ecosystems. Relevant doses are found not only in the vicinity of emitters but also elsewhere due to long-range transport. In Austria, heavy metals and radionuclides are monitored in the framework of several national and European monitoring networks (National Monitoring Grid, Austrian Bioindicator Grid, UN-ECE/ICP-Monitoring Network, Austrian Soil Monitoring System and BioSoil, respectively, and Radionuclide Monitoring Grid Upper Austria). On the one hand, since the 1980s, the input of heavy metals was significantly decreased due to emission reduction measures. On the other hand, radionuclides are still present in spruce needles and forest soils since the Tschernobyl disaster in 1986. The evaluation showed that in general, Austrian forest ecosystems per se are not endangered by heavy metal and radionuclide deposition. Nevertheless, the accumulation of heavy metals may cause a permanent physiological stress for forest plants, especially at "hot spots".