Tree bark as a bioindicator of air pollution in the city of Stassfurt, Saxony-Anhalt, Germany

To assess the atmospheric 'contaminant load' of the different sites in the city, an air quality index (AQIB) was calculated from the outer bark data and plotted on a map of the city. The mean atmospheric 'contaminant load' of Stassfurt is above the mean 'contaminant load' of the comparison sites in all parts of Germany. A bioaccumulation index (BAIB) for the inner bark was also calculated and plotted on a colour map. The bioaccumulation in inner bark indicates a plant availability of contaminants in the environment and their uptake by the tree. Comparison of the distribution patterns of the air quality index with the bioaccumulation index confirms the influence of the different contaminant sources in the study area.