. - Boron (B) is a crucial micronutrient needed for plant growth. This study investigated the effect of B addition (0.5 mg kg-1-low, and 5 mg kg-1-high) on lettuce (Lactuca sativa L.) plants grown in the soil and hydroponically. The results showed that B addition causes a differential increase in B concentration in lettuce leaves depending on the cultivation system. In soil-grown plants, a statistically significant increase in lettuce B concentration was shown with increasing B treatments compared to the control. Moreover, the B concentrations measured in lettuce were within the optimal level for healthy lettuce. While hydroponically-grown plants showed a statistically significant increase in lettuce B concentration at high B treatment compared to the control and low B treatment. However, the high B treatment in hydroponics caused a very high B concentration in lettuce (196.4 mg kg-1) leading to toxicity expressed by the decrease in normalized difference vegetation index (NDVI) and chlorophyll content. Therefore, B concentration should be below 5 mg kg-1 for hydroponically-grown lettuce. Soil total and available B concentrations increased with B addition and considered a sufficient level. The other soil physicochemical parameters did not reveal a statistically significant difference with the B treatments, except a modest increase in pH, suggesting that the soil has a great homeostatic capacity. Additionally, the results showed that hydroponically-grown lettuce performs much better in terms of biomass production.

Phytostabilization is a green, cost-effective technique for mine rehabilitation and ecological restoration. In this study, the phytostabilization capacity of Erica australis L. and Nerium oleander L. was assessed in the climatic and geochemical context of the Riotinto mining district, southwestern Spain, where both plant species colonize harsh substrates of mine wastes and contaminated river banks. In addition to tolerating extreme acidic conditions (up to pH 3.36 for E. australis), both species were found to grow on substrates very poor in bioavailable nutrients (e.g., N and P) and highly enriched with potentially phytotoxic elements (e.g., Cu, Cd, Pb, S). The selective root absorption of essential elements and the sequestration of potentially toxic elements in the root cortex are the main adaptations that allow the studied species to cope in very limiting edaphic environments. Being capable of a tight elemental homeostatic control and tolerating extreme acidic conditions, E. australis is the best candidate for use in phytostabilization programs, ideally to promote early stages of colonization, improve physical and chemical conditions of substrates and favor the establishing of less tolerant species, such as N. oleander.

Restoration potential of mine wastes or approaches to improve soil conditions and to ameliorate phytotoxicity on these sites may be simulated in standardized greenhouse experiments. Plants can be cultivated side by side on materials from different origins in dilution series with defined admixtures of certain aggregates. Mine wastes used in the present study originated from Fenice Capanne (FC, Tuscany, Italy) and Altenberg (ALT, Saxony, Germany). Tailings of the Italian site contain high concentrations of lead, zinc, arsenic and sulphur while tin, wolfram, molybdenum and lithium are highly elevated in the German mine waste. We tested growth responses of five crop species and analyzed concentrations of various metals and nutrients in the shoot to evaluate the toxicity of the FC mine waste and found oilseed rape being the most and corn the least resistant crop. Interestingly, oilseed rape accumulated seven times higher levels of lead than corn without showing adverse effects on productivity. In a subsequent comparison of FC and ALT mine waste, we cultivated different species of buckwheat (Fagopyrum spec.), a fast growing genus that evolved in mountain areas and that has been shown to be tolerant to low pH and high concentrations of metals. We found that the FC mine waste was more toxic than the ALT substrate in F. tataricum and F. esculentum. However, lower admixtures of FC material (10%) resulted in stronger growth reductions than higher proportions (25%) of the mine waste which was primarily related to the slightly lower pH and higher availability of essential metals due to the admixture of sand. These results confirm the importance of managing the soil chemical and physical characteristics of wastelands and call for the development of assisted reclamation to prepare sites for regular biomass production.

The aim of this study was to evaluate the potential use of Cistus ladanifer in the restoration of the sulfide mine of Riotinto (SW, Spain). A field study was performed sampling three different mining and one uncontaminated sites (control) where C. ladanifer was already established. Soil physico-chemical properties as well as nutrients and potential toxic elements in the different plant parts and soil were evaluated. In comparison with the control site, soils of Riotinto had a lower pH and P concentration, high concentration of Al and Fe oxides and a very low Ca availability (Ca:Mg:K 4:2:1). In general, the concentrations of Ca, Mg, K, P, Sin leaves and stems of plants from Riotinto and the control site were in the same range whereas those of As, Cd, Cu, Mn, Ni, and Zn were higher in the samples from the mining area. The element accumulation pattern was leaves > stem and root cortex > fine roots > inner tissue of roots. The plants from mining sites were able to translocate Cd, Mn, Ni and Zn from roots to shoots. The chemical composition of the plants sampled in the mining area reveals that, with some exceptions, C. ladanifer has excluder behaviour for most potentially toxic elements. The efficient nutrient uptake in such harsh environment in which low nutrient availability combines with high concentration of heavy metals provides the species as C. ladanifer with a high adaptation capacity, an important feature for its use for re-vegetation and stabilization of soils affected by mine wastes. (C) 2016 Elsevier B.V. All rights reserved.

Urban parks play important role in providing social and ecosystem services; the improvement of air quality through the absorption of gaseous pollutants and the interception of airborne particles is one the most important services of urban trees within those parks. Surveys performed in Italian urban environments show that leaves of Holm oak (Quercus ilex L.) are efficient accumulators of airborne trace elements and polycyclic aromatic hydrocarbons, but few data are available on the uptake of gaseous pollutants such as O-3, NO2. This study aimed at determining, with passive samplers, seasonal variations in O-3 and NO2 air concentrations under the canopy of Q. ilex and in an adjacent open area at increasing distances (1, 5, 10m) from a busy road in Siena. The survey was performed in July, November 2011, January, April 2012; the results showed a similar seasonal distribution of average O-3 concentrations along the two transects, with much higher values (up to 69 mu g m(-3)) in July. On the contrary, the highest NO2 concentrations were recorded in January and in all seasons their distribution pattern was characterized by a decrease of average values at increasing distances from the road, especially under the Q. ilex canopy. Although preliminary, results indicate that in Siena Q. ilex trees attenuate NO2 concentrations but not O-3.

Concentrations of 12 elements (Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb and Zn) and 16 EPA-listed PAHs were detected in Quercus ilex leaves and the epiphytic moss Leptodon smithii collected at urban, periurban and extraurban holm oak stands, in two Italian Regions (Campania and Tuscany). Levels of environmental contaminants were generally higher in leaves and moss from urban areas than periurban and extraurban ones and samples from Campania had the highest PAH content. The epiphytic moss accumulated higher concentrations of trace elements than leaves and the latter showed a higher accumulation capability for PAHs, especially for those with low molecular weight. The different bioaccumulation in leaves and moss were explained in terms of their distinctive morphological and ecophysiological characteristics. The combined approach seems a promising tool for the monitoring of a wide range of pollutants in Mediterranean urban and extraurban environments.

To define a harmonized methodology for the use of moss and lichen bags as active monitoring devices of airborne trace elements in urban areas, we evaluated the element accumulation in bags exposed in Naples in different spring weather conditions for 6- and 12-weeks. Three different pre-exposure treatments were applied to moss and lichen materials: water-washing, acid-washing and oven-drying. During the different exposure periods in the Naples urban environment the moss accumulated always higher amounts of elements (except Hg) than lichens and the element accumulation increased during wetter weather and higher PM(10) conditions. The oven pre-treatment did not substantially modify the morphology and element composition of moss and the exposure in bags of this material for 6-weeks was sufficient to detect the pattern of airborne trace elements.

The effects of Tinto River water on Erica andevalensis growth, biochemical indicators and elemental concentration and distribution were investigated under laboratory conditions. High levels of toxic elements such as B, Fe and S and acidic pH characterized the river water. Plant analysis revealed that the concentration of Al, B, S and Fe increased in all plant organs reaching in some cases values in the toxicity range. Plants transferred into river water stopped growing and stress was manifested by plant water loss, increase in peroxidase activity and decrease of chlorophyll a concentration. Significant decreases of free amino acid concentration were found in shoots and roots of plants grown in diluted river water. The results indicated that Tinto River water acidity and its excess in soluble elements produced altogether severe alterations in roots affecting plant water and nutrient uptake and leading to the massive entry of some metals (e.g. Fe, Al) with toxic effects. Scanning-electron microscopy (cryoSEM and ESEM) observations showed that E. andevalensis had not exclusion mechanisms of Cu, Fe and S therefore it was not able to reduce translocation to aerial parts.

To enhance the reliability of the moss and lichen transplant technique for active biomonitoring of trace metals in urban environments, we evaluated the natural variability in the chemical composition of the (epilithic and epiphytic) moss Hypnum cupressiforme and the epiphytic lichen Pseudevernia furfuracea from two reference areas in NE Italy. Green shoots of epilithic mosses and lobes of epiphytic lichens from larch branches showed rather homogenous composition and were selected for the exposure in nylon bags. As different physico-chemical pre-treatments are usually applied to selected cryptogamic material before its exposure, we also evaluated the effects of oven-drying at 120 °C for 24 h, washing in 1 N HNO3 solution, and in 0.5% NH4 oxalate solution at 85 °C for 15 h on the chemical composition and morphology of water-washed moss shoots and lichen lobes. Pre-treatments remarkably changed the chemical composition of selected materials but not their surface morphology.

Lobes of the lichen Pseudevernia furfuracea (L.) Zopf and shoots of the moss Hypnum cupressiforme Hedw. were subjected to different treatments (water washing, oven drying, HNO3 washing, NH4-oxalate extraction) to assess the influence of vitality on accumulation efficiency, during a 6-week exposure in bags in two Italian cities, Trieste and Naples. No trend emerged between treatments, in terms of accumulation ability, for major and trace elements. Only water-washed lichens showed an increased C and N content after exposure in both cities. Element concentrations generally reached higher values in mosses than in lichens, especially for Al, Fe, and Zn (both cities), and for Cu, Mg and Na (Naples). Surface development strongly influenced accumulation capacity of the biomonitors. Quartzose and cation exchange filters revealed, on a weight basis, a poor performance. In urban environments, surface interception of atmospheric particulate seems to play a major role in accumulation, irrespective of organism vitality.

The localization of inorganic contaminants in lichens is an important step toward a better understanding of the accumulating capability and toxitolerance of species (Hauck et al. 2002). Different methods, such as sequential elution technique (Brown 1995; Tretiach et al. 1999), X-ray microanalysis (Hauck et al. 2002) and microscopic histochemistry (Garty & Theiss 1989), have been used.

Mercury emitted by anthropogenic and natural sources occurs in the atmosphere mostly in the gaseous elemental form, which has a long lifetime in tropical and temperate regions. Once deposited in terrestrial and aquatic ecosystems the metal is partly re-emitted into the air, thus assuming the characteristics of global pollutants such as persistent volatile chemicals. In polar regions, during and after the sunrise, the photochemically driven oxidation of gaseous Hg by reactive halogens may result in areas of greatly enhanced Hg deposition. Mercury concentrations in soils, lichens, and mosses collected in a stretch between 74 degrees 30' S and 76 degrees 00' S, in ice-free coastal areas of Victoria Land facing the Terra Nova Bay coastal polynya, were higher than typical Antarctic baselines. The finding of enhanced Hg bioaccumulation in Antarctic terrestrial ecosystems facing a coastal polynya strongly supports recent speculations on the role of ice crystals ("frost flowers") growing in polynyas as a dominant source of sea salt aerosols and bromine compounds, which are involved in springtime mercury depletion events (MDEs). These results raise concern aboutthe possible environmental effects of changes in regional climate and sea ice coverage, and on the possible role of Antarctica as a sink in the mercury cycle.

Lichens and mosses constitute the bulk of plant biomass in terrestrial ecosystems of continental Antarctica. On the hypothesis that cryptogams can be used as an early warning system to detect the effects of climatic changes on environmental biogeochemistry, we investigated the elemental composition and the main sources of soluble ions to the saxicolous lichen Unibilicaria decussata, in Victoria Land. Concentrations of major anions (Cl-, SO42-, NO3-) cations (Na+, Ca2+, Mg2+, NH4+) and trace elements (Al, Cu, Fe, Mn and Zn) were determined in lichens, snow, salt encrustations and wet filter papers laid on lichen supporting rocks. Enrichment Factors calculated using Na as marine reference element were close to I for most of analysed ions irrespectively of rock types. A crustal contribution of Ca, K and above all Cu was found in the lichen thalli growing on gabbro and ultramafic rocks. The uptake of marine ions in Umbilicaria thalli probably occurs directly from the snow and aerosols and indirectly through the solubilisation of salt encrustations on rock surfaces. Possible effects of predicted climatic changes on biogeochemistry of Antarctic terrestrial ecosystems were discussed.

The Colline Metallifere (Tuscany) was a major Italian mining district (FeS2, Ag, Cu, Pb, Zn) for centuries, and in the last fifty years it has become the most important area for the exploitation of geothermal resources. Leaves of the widespread oak Quercus pubescens and surface soils were collected from 90 sampling sites in the area and their elemental composition was compared. The results showed that the composition of oak leaves was not significantly affected by the presence of mineral deposits (metal sulphide ores) or soils with high concentrations of Cr, Mg, and Ni (ultramafic). Arsenic was the only element showing higher concentrations in leaves from sites with deposits of metal sulphide ores or As-polluted soils around abandoned smelting plants. Compared to the composition of epiphytic lichens and epigeic mosses from the same sites in the Colline Metallifere, the elemental composition of Q. pubescens leaves was less affected by element contributions from adsorbed soil particles. It was thus easier to evaluate atmospheric inputs of elements in oak leaves than in cryptogams.

Samples of the moss Hypnum cupressiforme and the epiphytic lichen Parmelia caperata were collected during the summer of 1999 in an area (Colline Metallifere, central Italy) intensively exploited in the past for metals (Cu, Fe, Pb, Zn) and currently for geothermal resources. Lichens were more sensitive than mosses to emissions of S compounds near geothermal fields and abandoned sulphide ore smelting plants. Comparison of elemental compositions of the two cryptogamic species from the same sampling sites showed significantly higher concentrations of lithophile elements (Al, Cr, Fe, Mn, Ni, Ti) in the moss and atmophile elements (Hg, Cd, Pb, Cu, V, Zn) in the lichen. Patterns of bioaccumulation of elements throughout the study area were quite similar for widespread pollutants such as S, B, As, Zn, Cr and Ni, but the lichen and the moss showed different distribution patterns of Hg, Cd and other elements subject to long-range atmospheric transport. These results are due to differences in the morphology and ecophysiology of mosses and lichens and indicate that these organisms cannot be used interchangeably as biomonitors of metals in areas with mineral deposits.

The aim of this study was a preliminary assessment of a possible role of human saliva in the diagnosis of some physiological and pathological changes in oral and body functions. Reliable procedures for collection and analysis of samples were established in order to assess total concentrations of Ca, K, Mg, Na, P, and Hg in whole unstimulated saliva. Possible relationships between element concentrations and sex, age, smoking, illness conditions, or side effects resulting from the use of drugs were investigated. The effects of stimulated or unstimulated collection procedures, dental prosthesis, and amalgam fillings were also evaluated. Total concentrations of major cations and Hg in whole saliva from 33 healthy adults living in the Siena district showed a coefficient of variation ranging from 11% (P) to 53% (Na) and average values were in the same range of those previously reported for unstimulated saliva. Healthy males had significantly higher concentrations of K, Na, P, and Na/K, Na/Ca, Na/Mg, and Na/P values than females. Age, smoking, dental prosthesis, and amalgam fillings had no significant effects on the concentrations of major elements. On the contrary, concentrations of Hg were positively correlated to the number of amalgam fillings and increased at a rate of about 1.9 µg/L for each filling. No correlations were found between Hg concentrations and those of major elements. Comparisons with literature data showed a different composition (particularly for Na and Hg concentrations) between unstimulated and stimulated saliva. Samples from patients affected by idiopathic pulmonary fibrosis had significantly higher concentrations of K and the maximum value was measured in a patient affected by acute pulmonary edema. This increase was likely the result of pharmacological treatments with tricyclic antidepressants and/or saline solutions. Data reported in this study, although preliminary, contribute to the assessment of levels of major cations (some of them very little investigated) and Hg in whole unstimulated human saliva and provides consistent support for further research on the possible use of this easy accessible matrix as a diagnostic tool of body function changes.

Samples of Quercus ilex leaves and of the inhalable fraction of atmospheric particulate (PM10) were collected along a busy road and in a park in Florence (Italy). Quantitative comparisons and correlations of element concentrations in PM10 collected by air samplers at two sites showed that Ba, Cu, Fe, Mn, Pb and Zn were the main metal pollutants emitted by vehicles in Florence. Very similar results were obtained by the analysis of Q. ilex leaves which were found to accumulate airborne metals as a function of the exposure time (i.e. their age). One-year-old leaves showed the highest rate of metal accumulation. Our results show that the progressive phasing-out of leaded petrol in Italy has resulted in a decrease of about 20% per year in the Pb concentrations in PM10. Both PM10 and Q. ilex analysis singled out Ba and Zn as valid tracers of automotive traffic instead of Pb. (C) 2000 Elsevier Science Ltd. All rights reserved.

Total concentrations of major and trace elements were determined in samples of the epilithic lichen Umbilicaria decussata from 24 ice-free areas in coastal Victoria Land (Antarctica). Overall average concentrations of trace elements except Cd were the lowest ever reported for lichens of the genus Umbilicaria. Specifically, the mean level of Pb in lichens from granitic rocks (0.46 +/- 0.18 microg g(-1) dry wt) was more than four times lower than the lowest record in Arctic lichens. No impact of local human activities was detected, but the elemental composition of U. decussata was affected by entrapment of soil or rock dust particles and probably by uptake of soluble elements from substrate. Relationships between elements and their distribution patterns in the study area indicated that the marine environment is the main source of major ions and perhaps of Cd in lichens. Accumulation of P was detected in samples from coastal sites frequented by seabirds. Although the present results can be taken as baseline levels of major and trace elements in Antarctic U. decussata from substrates with very different geochemical features, further research is necessary to evaluate the relative element contribution from each substrate with respect to those from snow, marine aerosol, salt encrustations and guano.

Heavy metals and organochlorine contamination were analyzed in tissues of red foxes (Vulpes vulpes) from the Province of Siena (central Italy). Mercury (Hg), cadmium (Cd) and lead (Pb) concentrations were assessed in liver tissues and the data were analyzed for differences in relation to sex and age. Overall Hg, Cd and Pb mean values were 0.16, 0.62 and 0.64 μg g _1 d.w., respectively. HCB, DDT and PCB concentrations were assayed in fatty tissues and muscle. The highest levels of those pollutants were found in muscle (0.47, 1.16 and 20.2 μg g _1 lipid basis of HCB, DDTs and PCBs respectively), rather than in fat (0.23, 0.49 and 7.2 μg g _1 l.b. of HCB, DDTs and PCBs respectively). Pollutant accumulation was analyzed in relation to sex, age and sexual maturity of females.

Physical and chemical characteristics and solution geochemistry of major and trace elements were investigated in an area of volcanic soil colonized by mosses at Edmonson Point (central Victoria Land) during the international BIOTAS (Biological Investigations of Terrestrial Antarctic Systems) expedition (BIOTEX) in the 1995–96 summer. The broad objective was to study the environmental factors involved in plant colonisation and survival in terrestrial continental Antarctic ecosystems. The results showed that moss distribution and survival throughout the summer was closely dependent on water supply. In Antarctic coastal ecosystems the environmental biogeochemistry is largely dominated by ions of marine origin. At the drier end of a hydrological gradient the dry cushions of Hennediella heimii were encrusted with salts and showed much higher concentrations of soluble ions (Na+, Cl−, K+, Ca2+, Mg2+, SO42−, NO3−) than those in adhering soil particles or in other moss species from wetter parts of the transect. Although salt encrustations may partly derive from sublimation of surface snow, comparisons between concentrations of soluble ions in the dry moss and those in the < 2 mm fraction of surface and deep soil showed an upward migration along the soil profile of soluble ions as the substratum dried out, between December and January, and their accumulation mostly on mosses. At the wet end of the transect messes were less affected by salt encrustations and there was evidence of Ca2+ uptake and an active cycling of nutrients.