Accumulation of Inorganic Contaminants

Human activities release large amounts of exchangeable elements into the environment and have become a major factor in altering biogeochemical cycles. This alteration is progressively affecting the long-established steady equilibrium between the Earth’s processes and biological evolution [50]. Increasing body burdens of potentially toxic elements in organisms, even from remote regions of the Northern Hemisphere far from significant sources of local pollution, have underlined the importance of establishing reliable monitoring systems at different scales. A reliable appraisal of pollutant concentrations in such an extremely variable compartment as the atmosphere needs a statistical approach based on a large number of samples in both time and space (see chapter 9, this volume). The high costs of establishing and managing automatic monitoring networks often limit the number of sampling stations and/or the number of pollutants considered. Thus, although very reliable, data from instrumental recording may be statistically weak and their integration with diffusion models cannot give reliable information about the deposition and impact of atmospheric pollutants on terrestrial ecosystems.