Stress on the Northern Tyrolean Limestone Alps by the Depositions of Pollutants

1996

zahlr. Lit. Ang.

Unselbständiges Werk

5943

200052166

Anthropogenous stresses to the forest ecosystems of the Northern Tyrolean Limestone Alps are caused by local emittors and long-range transport. Apart from the gaseous pollutants SO2, NOx and ozone, the proton, nitrogen and heavy metal depositions are particularly harmful. Investigation results from all over Austrian surveys (Austrian Bio-Indicator Grid, Austrian Forest Soil Monitoring System), air monitoring data from the Federal Province of the Tyrol, model calculations, and surveys from the Achenkirch area were used to describe the stress imposed by pollutants. The monitoring data were evaluated by using effect-related limiting values and/or Critical Loads. The evaluation of air monitoring data from the Northern Tyrolean Limestone Alps ahowed that pollution patterns vary greatly depending on altitude. In valleys, the effect-related limiting values for SO2 and NO2 are exceeded in agglomerations; at higher locations, ozone is a potential risk factor, particularly for sensitive species. In the needles of Norway spruce, which has been used as a bioindicator species, sulphur depositions were proved up to altitudes of 1200m. Attention should also be paid to the heavy metal depositions caused by anthropogenous emittors. They accumulate in the upper soil layers, increase with altitude and are important because they can influence soil-biological processes. Whereas the acid inputs in the Northern Tyrolean Limestone Alps are usually well buffered by the soil, excessive nitrogen inputs may cause negative effects on forest ecosystems.