Luigi Antonello Di Lella

Environmental geochemical maps of Italy from the FOREGS database

The Geochemical Atlas of Italy addresses the need for geochemical mapping of the country, based on FOREGS procedures. Data from samples of Italian topsoil, subsoil, stream water, stream sediment and floodplain sediment have been extracted from the FOREGS database and supplemented with data from eight new sample sites. In total 360 geochemical maps have been produced and spatial correlations have been found between the underlying geology and element abundances in the sampled media. The aim of the Geochemical Atlas of Italy is to document background/baseline chemical element variation at the national scale. It is found to be a suitable tool to support government decision-makers to assess trigger and action limits at the local scale, when considered in the light of the complex spatial variability of Italian geology. Maps presented here demonstrate that low density geochemical mapping is a viable tool to obtain an impression of natural element variation at the country scale and to identify areas where more detailed sampling is advisable.

Seasonal variations in intracellular trace element content and physiological parameters in the lichen Evernia prunastri transplanted to an urban environment

Abstract In this study we investigated the seasonal variations in the intracellular content of 14 trace elements (Al, As, Ba, Cd, Ce, Cr, Cu, Fe, Mn, Ni, Pb, Pd, Sb, Zn) and physiological parameters (namely chlorophyll a, chlorophyll b, ergosterol, photosynthetic efficiency, cell membrane integrity) in the thalli of the lichen Evernia prunastri (L.) Ach. exposed to an urban environment (Siena, central Italy). Lichen thalli were collected before each exposure period from an unpolluted area and transplanted to 16 sites; every 3 months the thalli were retrieved and replaced with new ones. Exposed-to-control ratios of trace elements revealed a marked intracellular accumulation of Cd in summer and autumn, and of Sb in autumn and spring, possibly as a result of vehicular traffic pollution. However, considering the low absolute concentrations of these elements, the intracellular fraction of depositions may hardly have caused an impairment of physiological parameters. As a matter of fact, indicators of photobiont vitality (content of chlorophylls a and b and photosynthetic efficiency) did not show any fluctuation across seasons, while changes in the indicators of mycobiont vitality (cell membrane damage and ergosterol content) overall did reflect some seasonal changes and/or lichen growth.