Chemical composition of Fagus Silvatica annual rings affected by local industrial pollution in northern Romania (Baia Mare region)

The development of urban areas, industrialization and increasing traffic intensity is a problem of air, soil and water contamination worldwide with various pollutants, some of which are heavy metals. The most significant sources of heavy metal pollution are industrial factories, processing of non-ferrous materials, mining activity and traffic intensity, with negative effects on both forest ecosystems and wildlife. This study was carried out in forest ecosystems affected by industrial pollution in the Baia Mare region (Maramureș). The study provides an analysis of the chemical elements accumulated in tree rings over 60 years, making it possible to analyze the dynamics of these elements over time. The sampling design was carried out systematically in order to make a comparison between trees in the intensively polluted area and those located at a fairly large distance, where local pollution had no effect. Thirteen chemical elements were analyzed, including heavy metals such as Cu, Pb, Zn, Fe and Mn. Higher concentrations of the elements Pb, Zn, Fe, Mn, Al, K, Si and Sr were found in tree rings from the intensively polluted area compared to those from the area unaffected by local pollution. Significant differences were found at 95% confidence interval for Zn, K and Ca concentrations.