Metal Accumulation In Mosses Research Articles

Using Bioindicators to Assess Heavy Metal Contamination in Surface Waters and Public Health Impacts

Objective: This study aims to explore the use of bioindicators for assessing metal contamination in surface waters and its effects on public health. Theoretical Framework: The persistence and variation of heavy metal contamination in the Ave River Basin over 15 years underscore the need for ongoing monitoring and intervention. The detection of elevated levels of chromium, cadmium, lead, and zinc in aquatic mosses highlights the continuing impact of industrial activities, particularly metal coating facilities, on the river's ecosystem. Method: In the study area, the Ave River and some of its tributaries, a monitoring programme of twelve sampling points was defined in two campaigns and eight metallic ions were determined in the laboratory by atomic absorption spectrophotometry (Cd, Pb, Cu, Cr, Fe, Hg, Ni and Zn). Results and Discussion: The highest metal accumulation in mosses was observed for iron (Fe), whereas the lowest accumulation was found for mercury (Hg) during Campaign II. The order of metal accumulation in the moss samples, from highest to lowest, was Fe > Zn > Cu > Cr > Ni > Pb > Cd > Hg. The Metal Pollution Index (MPI) revealed changes in contamination levels between campaigns. Research Implications: The contamination patterns suggest the influence of industrial activities, particularly metal coating facilities. Monitoring and mitigation efforts are necessary to address persistent heavy metal pollution in the Ave River Basin. Originality/Value: The results of this research will contribute to a better understanding of the sources and loads of pollutants discharged and responsible for the contaminants. This can be used to discourage potential polluters and better manage the basin's water resources and possible risks to human health.

Radionuclide and trace metal accumulation in a variety of mosses used as bioindicators for atmospheric deposition

Mosses can be used as biological monitors to study metal pollution and the depositional fluxes of radionuclides. In this study, we analysed the concentrations of radionuclides (210Pb (210Pbex), 7Be, 137Cs, 40K, 238U, 226Ra, 228Ra and 228Th) and metals (Fe, Zn, Cu, Al, Pb, Cd, Cr, Ni, V and Mn) in moss and soil samples from two different regions. The metal concentrations were higher in mainland China than in the Arctic region, and this is likely associated with the comparatively lower rates of industrial production and human activity in the Arctic region. Principal component analysis and correlation results revealed two radionuclides sources types in mosses, i.e., soil (40K, 238U, 226Ra, 228Ra and 228Ra) and atmospheric (210Pb (210Pbex), 7Be 137Cs). Clustering and correlation analyses showed that different sources such as traffic (suspended dust), fossil fuels, dry and wet deposition (atmosphere and rainfall), and soil contributed to metal accumulation in mosses. The correlation between radionuclides and metals supported these observations, confirmed the accuracy of our results, and suggests that radionuclides are useful for identifying the source of metals in moss samples. The concentration ratios (CR) values of the radionuclides and the bioaccumulation factor (BCF) and enrichment factor (EF) values of metals in mosses helped identify the most environmentally sensitive moss, i.e., BS (Bryum paradoxum), which can be used for screening and monitoring radionuclides and metal pollution in urban atmospheres. These results support the use of analysing radionuclides in mosses to identify metal sources, and the potential use of mosses can to determine the atmospheric deposition fluxes of radionuclides.

Use of Bioindication Methods in National, Regional and Local Monitoring in Poland—Changes in the Air Pollution Level over Several Decades

In Poland, the first studies using mosses as indicators of the heavy metal air pollution level were carried out in national parks already in the 1970s. They were continued later in 10-year intervals. In 1990, when Poland join the European Heavy Metals Deposition Program, the entire area of the country was included in such research. Moss surveys were repeated at five-year intervals, to varying degrees. Pleurozium schreberi samples were collected from 150 (1990) to over 300 sites (1995 and 2015) throughout the country, either in selected regions diversified in terms of both the level of industrialization and urbanization (2001 and 2015), or only in national parks (2005). On a small scale, changes in the level of heavy metals were recorded in the period from 1975 to 2014 in the Niepołomice Forest located near Kraków. Concentrations of ten heavy metals were constantly monitored. Additionally, in some moss surveys, other elements or compounds, such as 137cesium, PAHs and nitrogen were analyzed. During the 1990s, in all of Europe, there was a significant decrease in the level of heavy metals. In Poland, the spatial patterns of metal accumulation in mosses were similar throughout the entire study period: The southern part of the country, more industrialized and densely populated, is still the most polluted, and the northeastern part belongs to the cleanest regions. In the Niepołomice Forest, emissions from the big steel mill and from the Kraków agglomeration had the greatest impact on pollution from the 1970s to the 1990s, but lately the impact of local emission sources is more visible. Compared to other European countries, Poland and neighboring countries of Central Europe are at the forefront of the most polluted areas in Europe.

Current content of selected pollutants in moss, humus, soil and bark and long-term radial growth of pine trees in the Mezaparks forest in Riga.

The aim of this study was to evaluate the use of various indicators in the assessment of environmental pollution and to determine the response of pine to changes of pollution levels. Mezaparks is a part of Riga that has been subject to various long-term effects of atmospheric pollution and, in particular, historically from a large superphosphate factory. To determine the spatial distribution of pollution, moss, pine bark and soil O and B horizons were used as sorbents in this study, as well as the additional annual increment of pine trees. The current spatial distribution of pollution is best shown by heavy metal accumulation in mosses and the long-term accumulation of P2O5 pollution by the soil O horizon. The methodological problems of using these sorbents were explored in the study. Environmental pollution and its changes could be associated with the tree growth ring annual additional increment of Mezaparks pine forest stands. The additional increment increased after the closing of the Riga superphosphate factory.

Does heavy metal deposition affect nutrient uptake by mossPleurozium schreberi?

Heavy metals may influence chemical composition of plants, and thus shape elemental stoichiometry of plant communities. That is because some physiological processes aiming at neutralization of contaminant toxicity require increased acquisition of some nutrients (e.g. N, S, P or Ca). The aim of the study was to evaluate the heavy metal deposition in Poland using moss Pleurozium schreberi as a bioindicator, and check whether C/N, C/S, C/P and Ca/Mg ratios in mosses correspond with the accumulation of heavy metals. Heavy metal concentrations in mosses were highly variable across the study area – southern parts of the country, industrialized and densely populated, were the most contaminated. There were significant correlations between nutrient ratios and metal accumulation in mosses. Mosses seem to take 1) more N, P and S under Cu contamination, and 2) more Ca under Zn contamination. This increased acquisition of nutrients, mainly N and Ca, may be a response to higher toxicity of heavy metals. Further studies are required to exclude other causes for observed relationships.

Long-term monitoring of the metal accumulation in forests measured by use of the moss technique

This study aimed at analyzing the metal accumulation in mosses sampled in forests across Germany. The data that were used to this end were collected in the framework of the European Heavy Metals in Mosses Surveys conducted every 5 years since 1990 in at least 21 European countries. The moss surveys aim at uncovering the accumulation of up to 40 metals and, since 2005, nitrogen in mosses. Germany took part in the moss-monitoring campaigns 1990, 1995, 2000 and 2005. The sampling at up to 1,028 forest sites and the chemical measurements of the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), nickel (Ni), lead (Pb), antimony (Sb), titanium (Ti), vanadium (V) and zinc (Zn) followed a European guideline. The measurement data and the detailed sites descriptions were integrated into a geographical information system. The site and element-specific measurement data as well as their geostatistical surface estimations were analyzed by means of descriptive statistics and they were aggregated to multi-metal indices (MMI). The MMI represents the mean rank of each monitoring site or geostatistically estimated raster cell regarding all elements referred to. Hence, the metal bioaccumulation in German forests could be assessed as a whole over the period 1990–2005. The MMI was calculated for two sets of elements: Cr, Cu, Fe, Ni, Pb, Ti, V and Zn (MMI1990–2005) and As, Cd, Cr, Cu, Fe, Ni, Pb, Ti, V and Zn (MMI1995–2005). Element-specific percentile statistics and correlation analyses were performed to uncover element-specific developments over time. Furthermore, correlations between metal concentrations in mosses and depositions were calculated. In terms of the MMI1990–2005 and the MMI1995–2005, respectively, the metal bioaccumulation in the forests of Germany clearly decreased continuously between 1990 and 2000. Contrary to this, the MMI increased from 2000 to 2005. This also holds true for the medians of the element loads of As, Cr, Cu, Fe, Ni, Sb, Ti and Zn. The median bioaccumulation of Cd, Pb and V in the German forests do not follow this trend after they have been decreasing continuously since 1990 together with all other elements. Many of the elements show moderate correlations (r > 0.5) but these correlations could not be corroborated to be stable over time. Moderate to high correlations could be proven for the metal concentrations in mosses and depositions. The European moss monitoring allows for a long-term monitoring of the metal bioaccumulation in forests. The moss surveys complement and detail the deposition measurements in forest ecosystems in terms of high spatial resolution and a broad range of elements. No other Germany monitoring network allows for combination of measurement data with topographical, land use and ecological information describing the sampling sites and their surroundings to evaluate whether the measurements are influenced by site-specific or regional land characteristics. Other investigations would profit from such a comprehensive data base since factors could be detected which, besides the deposition rates, influence the metal bioaccumulation in forests: moss species-specific accumulation rates, canopy drip effects and the growth patterns of the sampled mosses. The investigation gives the latest comprehensive overview of the metal bioaccumulation in the German forests. The MMI approach allows summarising the temporal trends of element loads in mosses. The moss monitoring is a significant part of forest monitoring and unique regarding spatial resolution, elements covered, and consideration of site-specific and regional confounding factors in the statistical analyses and transparency and performance of data management.

Assessing spatial patterns of metal bioaccumulation in French mosses by means of an exposure index

The European Heavy Metals in Mosses Surveys (UNECE-ICP Vegetation) is a programme performed every 5 years since 1990 in at least 21 European countries. The moss surveys aim at uncovering the spatiotemporal patterns of metal and nitrogen bioaccumulation in mosses. In France, the moss survey was conducted for the third time in 2006. Five hundred thirty-six monitoring sites were sampled across the whole French territory. The aim of the presented study is to give an integrative picture of the metal bioaccumulation for the entire French territory without geographical gaps. Furthermore, confounding factors of the metal bioaccumulation in mosses should be investigated. Element loads of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), nickel (Ni), lead (Pb), antimony (Sb), vanadium (V) and zinc (Zn) measured in the French campaign 2006 were aggregated to a multi-metal index (MMI). This index was first introduced in the German moss surveys and represents the mean rank of each monitoring site or estimated raster cell regarding all elements referred to. Hence, the spatial variability of the metal bioaccumulation in France could be assessed as a whole. A comparison of the MMI map with the spatial patterns of the Cu loads in mosses was then drawn, as Cu originates to a large extent from urban sources. Applying CHAID, the MMI and the Cu loads in the mosses were further investigated with regard to confounding factors. The said results were discussed on the basis of recent scientific publications. The MMI surface map shows high values in strongly industrialized and urbanized regions as well as at sites of high altitude, lying, for example in the Massif Central and the French Alps. Accordingly, the CHAID decision tree consequently shows the altitude to be the statistically most significant influencing factor of the MMI followed by the sampled moss species. As for the MMI map, the surface map for Cu mirrors urban agglomerations, as high values can be found in the areas of Greater Paris, Lyon and Marseille. The CHAID tree for Cu revealed the sampled moss species and the ratio of urban land uses within 5 km of the sampling sites to be the main influencing factors. The aggregation of metal bioaccumulation data was adopted for the French monitoring campaign. The influence of altitude, moss species-specific accumulation rates and urban emissions on the bioaccumulation is confirmed by international scientific publications. Nevertheless, the confounding factors in France differ from those derived from the German data, where the MMI was mainly associated to canopy drip effects and the growth patterns of the sampled mosses. The Cu and the MMI maps give a comprehensive overview of the metal bioaccumulation in France without geographical gaps. Hence, this approach allows summarising the spatial patterns of eleven element loads in mosses by use of geostatistics and percentile statistics. The presented metal integrating approach should be applied on data from past French moss surveys and on those to come. Additionally, the decision tree analyses should be carried out to examine possibly changing boundary conditions of the metal accumulation in mosses over time.

Temporal trends (1990-2005) in heavy metal accumulation in mosses in Slovakia

Biomonitoring of multielement atmospheric deposition using terrestrial moss is a well-established technique in Europe. The moss samples of Hylocomium splendens, Pleurozium schreberi and Dicranum sp. were collected in Slovakia. Separately we evaluated the atmospheric deposition in the National Parks (Vysoke Tatry, Nizke Tatry, Zapadne Tatry -Jelenec, Slovenský raj) and in a landscape protection area (Velka Fatra). In comparison to the median northern Norway values of heavy metal contents in moss, the Slovak atmospheric deposition loads of elements were found to be higher. The survey has been repeated and in this paper we report on the temporal trends in the concentration of Cd, Cr, Cu, Fe, Hg, Ni, Pb, V and Zn between 1990 and 2005. Metal- and sites-specific temporal trends were observed. In general, the concentration of Cd, Cr, Cu, Fe, Hg, Ni, Pb, V and Zn in mosses decreased between 1990 and 2005; the decline was higher for Pb than for Cd. The observed temporal trends for the concentrations in mosses were similar to the trends reported for the modelled total deposition of cadmium, lead and mercury in Europe. The level of elements, determined in bryophytes reflects the relative atmospheric deposition loads of elements at the investigated sites. Factor analysis was applied to determine possible sources of trace element deposition in the Slovakian mosses.

Metal accumulation in mosses: Local and regional boundary conditions of biomonitoring air pollution

In der Fachliteratur zur Bioindikation werden Hypothesen diskutiert, welche Faktoren die Metallakkumulation von Moosen neben der atmospharischen Deposition beeinflussen. Jedoch ist keine statitische Analyse bekannt, die diese Hypothesen mit grosen und einheitlich erhobenen Datensatzen uberpruft. Deshalb wird untersucht, ob Standortmerkmale wie Hohe uber NN, Meeresnahe, Kronentraufeffekt, Niederschlag, Moosart oder unterschiedliche Analyseverfahren statistisch relevanten Einfluss auf die Ergebnisse des Moos-Monitorings haben. Grundlage sind Messdaten der UNECE Heavy Metals in Mosses Surveys, Probenentnahmeorte beschreibende Metadaten sowie Flachendaten zu Niederschlag, Hohe und Landnutzung Deutschlands. Ob ein statistisch signifikanter Unterschied zwischen den Metallgehalten in Abhangigkeit von der Hohe der Probenentnahmeorte uber NN, ihrer Meeresnahe sowie ihrer Lage diesseits und jenseits von Staatengrenzen besteht, wird mit dem U-Test gepruft. Mit Spearman-Rangkorrelationsanalysen werden die statistischen Zusammenhange zwischen Metallakkumulation und Meeresnahe sowie Hohenlage uber NN quantifiziert. Neben den bivariaten Analysen wird Classification and Regression Trees (CART) angewendet, um aus der Gesamtmenge der vorliegenden Pradiktorvariablen diejenigen Faktoren zu bestimmen, die den grosten Einfluss auf die Metallbioakkumulation haben. Die Ergebnisse der statistischen Analysen werden mit entsprechenden Erkenntnissen aus der internationalen Fachliteratur abgeglichen. Es zeigt sich, dass vor allem die Moosart, der Kronentraufeffekt und der Niederschlag die Metallakkumulation in den Moosen beeinflussen. Diese Faktoren korrelieren starker mit der Metallbioakkumulation als die Quellen-bezogenen Pradiktoren wie Verkehr- und Siedlungsflachen. Die statistische Analyse des Einflusses standortlicher Randfaktoren auf die Metallbioakkumulation anhand flachendeckend vorliegender Mess- und Metadaten und Flacheninformationen zu Niederschlag, Hohe und Landnutzung ist die erste ihrer Art weltweit. Die entsprechenden Ergebnisse spiegeln den internationalen Forschungsstand weitestgehend wider, doch sind zu deren Verdichtung weitere statistische Analysen mit anderen nationalen Datenbestanden notwendig. Auch sollten im Sinne einer Sensivitatsanalyse alternative Entscheidungsbaumverfahren eingesetzt und deren Ergebnisse verglichen werden. Da die Randbedingungen der Datengewinnung von der Probenentnahme bis zur statistischen Analyse europaweit nicht vollig identisch sein konnen, mussen nicht nur die Messdaten, sondern auch — wie in Deutschland seit der Kampagne 2000 — geeignete Metadaten zum Datenerzeugungsprozess in Datenbanken dokumentiert und zusammen mit den Messdaten ausgewertet werden. Die Moosmonitoring-Verfahrensrichtlinie sollte uberarbeitet werden, um die aufgezeigten Einflusse emzuschranken, die Verfahrensstandardisierung voranzutreiben sowie die Qualitatskontrolle zu effektivieren. Hierzu sollte es gehoren, dass die Informationen zu den Moosprobenentnahmestandorten integraler Bestandteil der Datenauswertung werden. Grundsatzlich bedarf es einer statistisch fundierten Grundlagenstudie, in der die Hypothese artspezifischer Stoffakkumulation in Moosen uberpruft wird. Sollte die hier vorgestellte Datenauswertung mit den Ergebnissen der Messkampagne 2005 dieselben Resultate liefern, sollten nach Naturraumen differenzierte Korrekturfaktoren fur den Traufeinfluss, die regional unterschiedlichen Niederschlagsverhaltnisse und die Moosart auf die Metallgehalte in den Moosen angewendet werden.

CHAID Models on boundary conditions of metal accumulation in mosses collected in Germany in 1990, 1995 and 2000

The European heavy metals in mosses surveys allow mapping the metal accumulation in mosses indicating atmospheric deposition. Yet, there is still great uncertainty on how local and regional phenomena influence the atmospheric metal bioaccumulation. Therefore, the presented study aims at ranking factors that affect the spatial patterns of the metal concentrations in the mosses. Applying chi-square automatic interaction detection (CHAID) to the German moss measurements and related sampling site-specific descriptions taken from the surveys in 1990, 1995 and 2000 and supplementary land cover data, the spatial variation in metal concentrations in mosses were proved to depend mostly on different moss species, canopy drip and distance to the sea. Most of these findings could be corroborated by classification tree analyses on the same data as presented in another study. The results of both the studies should be verified by applying the same methodology using additional emission and deposition data and monitoring information from other countries participating in the UNECE moss surveys.

Metal accumulation in mosses across national boundaries: Uncovering and ranking causes of spatial variation

This study aimed at cross-border mapping metal loads in mosses in eight European countries in 1990, 1995, and 2000 and at investigating confounding factors. Geostatistics was used for mapping, indicating high local variances but clear spatial autocorrelations. Inference statistics identified differences of metal concentrations in mosses on both sides of the national borders. However, geostatistical analyses did not ascertain discontinuities of metal concentrations in mosses at national borders due to sample analysis in different laboratories applying a range of analytical techniques. Applying Classification and Regression Trees (CART) to the German moss data as an example, the local variation in metal concentrations in mosses were proved to depend mostly on different moss species, potential local emission sources, canopy drip and precipitation.

Spatiotemporal variability of metal accumulation in mosses. Analysis of measurement data and metadata by statistics and GIS

Spatiotemporal variability of metal accumulation in mosses. Analysis of measurement data and metadata by statistics and GIS

Time Series of Metals in Mosses and their Correlation with Selected Sampling Site-Specific and Ecoregional Characteristics in Germany * (9 pp)

The UNECE Heavy Metals in Mosses Surveys provide exposure data (Predicted Environmental Concentrations--PEC) for ecotoxicological risk assessments by measuring the accumulation of several metals in naturally growing mosses throughout Europe. Germany took part in the monitoring campaigns 1990, 1995 and 2000. The article deals with the description and application of the extensive methodical design developed to investigate the following three hypotheses: 1. The metal accumulation in mosses measured at up to 1000 sites may be geostatistically extrapolated from the sampling sites to ecoregions in order to transform the site-specific PEC values to surface PEC values. 2. The metal specific measurement values may be aggregated to metals integrating accumulation indices. 3. The ecoregional situation as well as sampling site-specific topographical features such as altitude, slope gradient or direction influence the accumulation of metals in mosses. The methodical design integrates several data sources as well as statistical analysis and GIS techniques: The site-specific data on metal accumulation are geostatistically transformed to valid surface data on metal accumulation. The sampling site-specific measurement data and the estimated surface data on the accumulation of As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Sb, Ti, V and Zn are aggregated to integrative metal accumulation indices by means of percentile statistics. The metal-specific estimated data and the metals integrating accumulation indices are correlated with site-specific data on altitude, slope gradient and direction as well as with the ecoregional conditions derived from a multivariate ecoregionalisation. The mean multi-metal accumulation index for the whole of Germany over the ten year period from 1990 to 2000 was related to the accumulation indices within each of the ecoregions and each of the monitoring campaigns 1990, 1995 and 2000. In addition to this ecoregionalisation of the temporal trends of metal accumulation, the hot spots of accumulation are mapped. The Heavy Metals in Mosses Survey 2000 reveals low metal concentrations in most European countries. In Germany, all metals decreased about 22% (Cu) to 64% (Pb) from 1990 to 2000. Mapping concentrations as dot maps deliver the most unbiased and detailed picture of the spatial structure of the metal accumulation in mosses. This information, detailed with respect to metal species and sampling site, is spatially generalized by means of geostatistical estimation. According to the cross-validation, the precision of the geostatistical estimation is quite good so that the extrapolation does not bias the spatial structure, but helps to clarify it. By percentile statistics, an ordinally scaled multi-metal accumulation index is calculated and spatially differentiated over time in terms of ecoregions which were calculated by means of Classification and Regression Trees (CART). The integrative statistical analysis reveals declinations of up to 80% of the multi-metal accumulation in some of Germany's ecoregions from 1990 to 2000. The monitoring of heavy metal bioaccumulation by means of mosses is an effective and cheap method for the analysis of the environmental concentrations of metals accumulated in terrestrial ecosystems. Geostatistics, percentile statistics, cross-tabulations and ecoregionalisation serve well to clarify the spatial and temporal trends in the large data sets coming out of the UNECE Heavy Metals in Mosses Surveys: By combining these statistical methods and integrating them into a geographical information system (GIS), they allow to detect and map the spatial-temporal trends of metal accumulation, to calculate metal-integrating accumulation indices, to describe temporal trends of metal accumulation within ecoregions, and to detect and map hot spots. The spatial and temporal trends of metal accumulation in mosses should be linked with deposition data and data on the vitality of forest ecosystems, as well as with data on human health. Statistical valid interspecies calibration is needed. The integrated methodology of data evaluation presented in the article at hand should be implemented in the future UNECE Heavy Metals in Mosses Surveys. The hot spot areas should be investigated with special care in the 2005 survey to prove if the PEC values of the metals exceed the Predicted no Effect Concentrations (PNEC values). In addition to the metals, the 2005 survey should monitor the nitrogen accumulation in mosses.

Integrative Monitoring Analysis Aiming at the Detection of Spatial and Temporal Trends of Metal Accumulation in Mosses

Goal and Scope. The UNECE heavy metals in Mosses Surveys provide data on the accumulation of metals in naturally growing mosses throughout Europe. Using Germany as an example, this article concentrates on the elaboration and application of methods of data analysis that are necessary for a comprehensive interpretation of spatial and temporal trends in metal accumulation. Methods and Results. The sampling of mosses, and the chemical analysis of Cr, Cu, Fe, Ni, Pb, Ti, V and Zn in 1990, 1995 and 2000 are summarized briefly. The variogram analyses detect distinct autocorrelation structures in the sample data which may consequently be estimated for all sites in Germany without monitoring metal accumulation by means of ordinary kriging. A procedure for the geostatistical detection of spatial outliers was developed and applied and, after the elimination of the spatial outliers, several measurements were seen to indicate an adequate quality of the geostatistical estimations. The cluster analyses of the z-transformed estimation data result in a nominal multi-element index that indicates regional metal accumulation types over time. Percentile statistics serve for computation of an ordinal, scaled, multi-element accumulation index which is spatially differentiated over time in terms of multivariate, statistically defined ecoregions. The integrative statistical analysis reveals, from 1990 to 2000, that the metal accumulation declines up to 80% in some of the ecoregions. Hot spots of metal accumulation are mapped and interpreted by means of metadata analysis. Conclusions. Dot maps depict the spatial structure of the metal accumulation without spatial bias. This information, detailed with respect to metal species and space, should be generalized for better supporting the interpretation. The combination of geostatistical analysis and estimation, percentile and multivariate statistics is suitable for the calculation of indices that serve for a comprehensive mapping of metal accumulation in the ecoregions over time, for quantifying the bias of the surface estimation, and for mapping spatial outliers and hot spots of metal accumulation.

Total reflection X-ray fluorescence and energy-dispersive X-ray fluorescence analysis of runoff water and vegetation from abandoned mining of Pb–Zn ores

The present work reports on the heavy metal content: Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd and Pb in running waters and vegetation around abandoned mining areas. Two species of mosses ( Dicranum sp. and Pleurocarpus sp.) and three different species of wild grass ( Bromus sp., Rumex sp. and Pseudoavena sp.) growing on the surrounding areas of old lead–zinc mines (Aran Valley, Pyrenees, NE Spain) have been analyzed. Both water and vegetation were collected in two different sampling places: (a) near the mine gallery water outlets and (b) on the landfill close to the abandoned mineral concentration factories. For the heavy metal content determination, two different techniques were used: total reflection X-ray fluorescence for water analysis and energy-dispersive X-ray fluorescence for vegetation study. Surface waters around mine outlets exhibit anomalous content of Co, Ni, Zn, Cd. Stream waters running on mining landfills exhibit higher Cu, Zn, Cd and Pb than those of the waters at the mine gallery outlets. The results allow us to assess the extent of the environmental impact of the mining activities on the water quality. The intake of these elements by vegetation was related with the sampling place, reflecting the metal water content and the substrate chemistry. Accumulation of metals in mosses is higher than those exhibited in wild grasses. Furthermore, different levels of accumulation were found in different wild grass. Rumex sp. presented the lowest metal concentrations, while Pseudoavena sp. reported the highest metal content.