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Soil contamination in outdoor shooting ranges (OSRs) is a major threat for human health, particularly when, after the end of activities, the land is used for recreational areas or agricultural production. The status of land degradation of an OSR in southern Italy was assessed using a multisensor approach. It was based on: i) proximal sensors, including electromagnetic induction (EMI) for measuring soil electrical conductivity (ECa) and magnetic susceptibility (MSa), γ-ray spectrometry for K, eU and eTh analyses and ultrasonic penetrometry detecting cone index (CI) data representative of soil's strength, ii) field surveys on soil thickness (ST), and iii) laboratory analyses of potentially-toxic-elements (PTEs) by portable X-ray fluorescence spectrometry and polycyclic aromatic hydrocarbons (PAHs) by gas-chromatography. Spatial variability of measurements was modelled and mapped using geostatistical methods. The most densely measured covariate (i.e., the ECa of the topsoil) was used within kriging with external drift to improve the PTEs predictions. The PTEs maps were complemented by maps of spatial uncertainty. A robust multivariate principal component analysis (rPCA) was applied to proximal sensor and laboratory data and allowed to identify associations of PAHs, lead, CI with the topsoil ECa along the first component (PC1), highlighting the correlation between land anthropogenic effects and EMI measures; while the association between the ST (estimating the depth of underground travertine hard-layers) and the bottom soil ECa and MSa along the second component (PC2) evidenced the influence of soil stratigraphy on the EMI measures. This study demonstrates that the simultaneous use of different proximal sensors associated with laboratory analysis can allow to assess and model the spatial variability of the land degradation status of an OSR, including soil compaction, organic and inorganic contamination. The correlation between EMI data with the PTEs content highlights the potential of this technique in the field of soil contamination.

RESUMEN

The results of trace element content analysed in Sphagnum capillifolium and Pseudevernia furfuracea exposed in bags in 1999 are reconsidered to evaluate the reliability of moss and lichen transplants to detect urban trace element atmospheric pollution, using Naples as a case example. After 4 months' exposure, trace element concentrations were at least twice as high as the pre-exposure values and in general higher in Sphagnum than in Pseudevernia. Moss samples were enriched in the following order: As=Cu>Mo>Pb>V>Co>Cr>Zn; lichen samples in the order: Mo>Cu>As=Co=Ni>V>Pb. Based on the calculation of a cumulative load factor, all sites located along the coast had higher trace element loads compared to sites in the hilly inland area. Complementary SEM, TEM and EDS observations showed, despite significant damage to tissue and cell integrity, the recurrent presence of particulate matter in moss and lichen, indicating the considerable presence of dust in the urban atmosphere which, according to chemical composition, may be due both to anthropogenic and natural sources such as volcanic rock and soil and sea salts.

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RESUMEN

The accumulation ability of the major elements sulphur, nitrogen and carbon by the moss Sphagnum capillifolium (Ehrh.) Hedw. and the lichen Pseudevernia furfuracea (L.) Zopf exposed in bags in Naples urban area,was investigated. Bags were exposed at the beginning of July 1999 and gathered in two subsequent moments: at the end of the dry season (after 10 weeks of exposure) and during the wet season (after 17 weeks of exposure), to include the effects of rainy conditions. Sulphur and N content of the lichen increased all over the exposure period, while the level of C did not change significantly either after 10 or 17 weeks of exposition. For the moss the S accumulation was limited to the dry period of exposure, whereas N and C content decreased with exposure. Results, in contrast with those obtained in a previous study on trace elements bioaccumulation [Adamo et al., Environmental Pollution, (2003) 122, 91-103], suggest that accumulation of gaseous pollutants is strongly influenced by biomonitor vitality and that lichen bags are a more reliable and effective tool for monitoring S, N and C atmospheric depositions in urban areas compared to moss bags, because of greater lichen resistance to dry and stressing conditions of urban environment.

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RESUMEN

This paper presents the results of a bioaccumulation study of trace elements in the Naples urban area based on the use of the moss Sphagnum capillifolium (Ehrh.) Hedw. and the lichen Pseudevernia furfuracea (L.) Zopf exposed in bags in 23 sites. Moss and lichen bags were exposed for 4 months starting from the beginning of July 1999. Bags gathering was carried out after 10 weeks of exposure, at the end of the dry season, and after 17 weeks, during the wet season. The elements Al, As, Ca, Cd, Cr, Co, Cu, Fe, K, Mg, Mn, Mo, Ni, Pb, Ti, V and Zn were analysed by inductively coupled plasma-mass spectrometry ICP-MS in both biomonitors. For the majority of the elements the total amounts found in S. capillifolium were higher than in P. furfuracea whether considering the whole period of exposure or the weekly uptake. It was observed that there was a much greater difference in metal accumulation by P. furfuracea between the dry and wet seasons compared with S. capillifolium. In the wet period, the lichen seems to accumulate a larger quantity of metals. With the exception of Mn, trace element concentrations did not appear to be significantly affected by the washing away of rainfall. K loss during exposure suggested cell membrane damage in both organisms. For P. furfuracea the K leakage was limited to the dry period of exposure. A clear distinction between "lithophilic" and "anthropogenic" elements was achieved by cluster analysis. Significant correlations were found among Fe-Cu-Cr-Ni, Pb-Cd-Co, V-Cr-Ni, Zn-Ni-Pb, suggesting a common source for each group of elements.

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