Moss Survey Research Articles

Entodontopsis setschwanica (Broth.) W.R. Buck & Ireland: An addition to West Himalayan Moss Flora with a brief note on the Genus Stereophyllum Mitt. and Entodontopsis Broth. in India

Entodontopsis setschwanica (Broth.) W.R. Buck & Ireland is an epiphytic moss belonging to family Stereophyllaceae. The plants have been observed during the survey and investigation of mosses of Garhwal Hills, Uttarakhand, Western Himalaya. In India the species has been reported from Darjeeling (West Bengal) in Eastern Himalaya and from Coimbatore (Tamil Nadu) in Western Ghats, South India so far. Now the species is being reported here for the first time from Pipalkoti in Chamoli district, (Garhwal Hills) Uttarakhand which is an addition to West Himalayan Moss Flora.

A Ten-Year Biomonitoring Study of Atmospheric Deposition of Trace Elements at the Territory of the Republic of Belarus

Abstract For the third time since 2005 atmospheric deposition of trace elements in Belarus was monitored by the moss technique widely used in Europe for air pollution studies. Samples of moss species of Hylocomium splendens and Pleurozium schreberi were collected at 86 sites over the Gomel, Vitebsk and Minsk Regions in the summer of 2015. A total of 30 elements were determined by epithermal neutron activation analysis. Studying of the temporal trends in Belarus was undertaken with the results obtained in previous moss surveys in 2005/2006 and 2010/2011. Comparison with the analogous data from the neighbouring countries showed relatively low contamination levels in Belarus for the most heavy and toxic elements. The results of survey 2010/2011 showed that, except Cr, other element concentrations reduce or are at the same levels.

Spatial structures of heavy metals and nitrogen accumulation in moss specimens sampled between 1990 and 2015 throughout Germany

BackgroundThe collection of atmospheric deposition by technical samplers and validated deposition modelling using chemical transport models is spatially complemented by using mosses as bioindicator: since 1990, the European moss survey has been providing data on element concentrations in moss every 5 years at up to 7300 sampling sites. In the moss specimens, heavy metals (since 1990), nitrogen (since 2005) and persistent organic pollutants (since 2010) were determined. Germany participated in all surveys with the exception of that in 2010. In this study, the spatial structures of element concentrations in moss collected in Germany between 1990 and 2015 were comparatively investigated by using Moran’s I statistics and Variogram analysis and mapped by use of Kriging interpolation. This is the precondition to spatially join the moss survey data with data collected at other locations within different environmental networks and to validate spatial patterns of atmospheric deposition as derived by technical sampling and modelling.ResultsThe calculated maps reveal a clear and statistically significant decrease of most heavy metals, but not of nitrogen, in moss. Due to decreasing element concentrations and the unchanged application of the element concentration classification for the mapping, the heavy metal maps for the survey 2015 do no longer depict much spatial variation.ConclusionsTherefore, in an upcoming study, this analysis needs to be complemented for the heavy metals by calculating maps that depict the spatial structure of survey-specific percentile statistics 1990, 1995, 2000, 2005 and 2015.

Atmospheric deposition of trace elements in Greece using moss Hypnum cupressiforme Hedw. as biomonitors

Mosses have been used for monitoring trace elements airborne pollution due to their ability to accumulate elements directly from wet and dry deposition. During the 2015/2016 European moss survey, ninety-five samples of Hypnum cupressiforme Hedw. were collected in Northern Greece. Mosses were analyzed to the content of Neutron Activation Analysis and the concentrations of thirty-three elements were determined. The contamination factors for the following elements Al, As, V, Ni, Fe, Cr, Zn were calculated. Information about air quality was provided through the study of atmospheric deposition of trace elements in mosses in the vicinity of Northern Greece.

Heavy metals and radionuclides concentrations in mosses from the region of Northern Greece

Mosses can be used as biomonitors for investigating the atmospheric deposition of radionuclides and heavy metals. They receive most of their nutrients directly from wet and dry deposition. During the 2015/2016 European moss survey, ninety-five samples of Hypnum cupressiformeHedw. were collected in Northern Greece. They were analyzed to the content of heavy metals using INAA. The concentrations of 137Cs,40K, 7Be and 210Pb radionuclides were determined using gamma spectrometry. Differences have been observed in the activity concentrations between mosses collected from ground surface, rocks, branches and near roots. Finally, a high sampling density was achieved, providing information for the elemental and radionuclides deposition from the atmosphere to terrestrial systems over the region of Northern Greece.

The Evaluation of Air Quality in Albania by Moss Biomonitoring and Metals Atmospheric Deposition.

The air quality of Albania is evaluated by trace metals atmospheric deposition using moss biomonitoring method. Bryophyte moss (Hypnum cupressiforme Hedw.) samples were collected during August and September 2015 from 55 sampling points distributed over the entire territory of Albania. The concentrations of Cr, Cu, Fe, Ni, Pb, V, and Zn in moss samples was determined by ICP-AES, ETAAS (As and Cd), and CVAAS (Hg) analysis. Spatial distribution and temporal trend of the moss elements is discussed in this study. Different variability was found in moss metal concentrations that may reflect their spatial distribution patterns and may identify the location of the areas with high contamination of each element. Compared with the measurements of moss collected in 2010, significant differences were found in the concentrations of As, Cr, Cu, Hg, Ni, Pb, and Zn. The differences between two moss surveys may reflect changes in the bioavailability of the elements resulting from wet and dry deposition respectively during 2015 and 2010moss biomonitoring survey. The pollution loading index that was applied to judge the content of metal contamination indicated moderate pollution throughout Albania. Examination of the potential ecological risk found that As, Cd, Cr, Hg, Ni, and Pb pose the highest potential ecological risks particularly in the areas with high metal contents. Factor analysis applied to investigate the probable sources of metals in the environment suggested that Al and Fe likely originated from natural sources. As, Cd, Hg, Pb, Cu, Zn, Ni, and Cr likely originated from anthropogenic sources associated with long-range transport, transboundary pollution and local emission sources.

Spatial distribution and temporal trend of airborne trace metal deposition in Albania studied by moss biomonitoring

This study describes the assessment of air quality in Albania using moss biomonitoring. The moss species, Hypnum cupressiforme (Hedw) sps., was used in this study. Mosses were collected during August and September 2015 at 55 sampling sites more or less homogeneously distributed over the entire territory of the country. The spatial distribution and temporal trends of trace metal atmospheric deposition were studied through the determination of twenty inorganic elements, Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Na, Ni, Pb, Sr, V, and Zn. ICP-AES, AAS (As and Cd) and CV AAS (Hg) analysis were used to determine the concentration of the elements. The obtained data show significant differences in the spatial distribution of the elements derived from different emission sources. High emission loads of anthropogenic elements (Cr, Ni, Cu, As and Zn) were detected in the East, and of sea salt elements, particularly Na and K, in the Western coastal line. The distribution trend of the trace metals was studied by comparing the current data with the data of a similar study performed in 2010. Due to the differences in airborne metal concentrations, their scavenging ratios from the atmosphere to the terrestrial ecosystems, and their different uptake-leaching rates during wet and dry deposition respectively of 2015 and 2010 moss grown period, different concentration levels were found in 2010 and 2015 moss metal concentrations. The 2015 moss concentration levels of anthropogenic elements Cr, Ni, Cu, As, Zn and Na had increased, while K, Mg and Hg moss concentration data had declined. Other elements show non significant differences in mosses of both monitoring periods.The contamination levels that were evaluated by calculating the contamination factor (CF) for each element provided similar results for the 2015 and 2010 moss survey. Factor analysis (FA) was applied to identify the possible sources of elements in the 2015 moss samples. Five dominant factors were identified representing long-range and local atmospheric transport of wind-blown soil dust particles (F1); local emission from chromium industry and wind-blown mineral dust particles (F2); anthropogenic sources of traffic emission and wind-blown fine mineral dust particles derived from geogenic origin natural transport from the marine environment (F4); and long-range atmospheric deposition (F5). This study emphasis that moss biomonitoring combined with data analysis and inventory of emission sources are important tools to assess air quality in Albania.

Entwicklung der Schwermetall- und Stickstoffkonzentrationen in Moosen in Deutschland

Development of heavy metals and nitrogen concentrations in moss throughout Germany Under the Convention on Long-range Transboundary Air Pollution, moss samples have been collected in Europe every five years since 1990 and evaluated for the concentration of heavy metals (since 1990) and nitrogen (since 2005). This article uses the data of this European Moss Survey to geostatistically evaluate and map the spatial distribution and temporal development of the heavy metals cadmium (Cd), lead (Pb) and mercury (Hg) as well as nitrogen (N) for Germany. Since the year of first sampling in Germany (Cd, Pb: 1990, Hg: 1995), heavy metal concentrations in moss tissue have decreased, while nitrogen concentrations have been remaining at almost the same level since 2005. Since 1990, Cd and Pb have shown a consistent hotspot of bioaccumulation within a broad band from North Rhine-Westphalia to Saxony, while for the other regions and with regard to Hg for most regions of Germany the geostatistical analyses corroborate that the spatial patterns of element concentrations in moss are changing across time. With regard to N, North Rhine-Westphalia and Mecklenburg-West Pomerania (2005–2015), as well as northwestern Germany (2015), proved to be a hotspot of nitrogen accumulation in moss. By contrast, the N concentration in mosses has decreased significantly in the southern German states, especially in Bavaria and Baden-Württemberg.

(Persistent) Organic pollutants in Germany: results from a pilot study within the 2015 moss survey

BackgroundSince 1990, every 5 years, moss sampling is conducted within the European moss monitoring programme to assess the atmospheric deposition of airborne pollutants. Besides many other countries, Germany takes regularly part at these evaluations. Within the European moss monitoring 2015, more than 400 moss samples across Germany were taken according to a harmonized methodology for the assessment heavy metal and nitrogen input. In a pilot programme, eight of these sites were chosen for additional investigations on a broad range of organic contaminants to evaluate their accumulation in moss and thereby their presence in atmospheric deposition in Germany. Target compound classes comprised polycyclic aromatic hydrocarbons (PAH), polychlorinated dibenzodioxins and –furans (PCDD/F), dioxin-like and non-dioxin-like polychlorinated biphenyls (dl-PCB, ndl-PCB), polyfluorinated alkyl substances, classical flame retardants as well as emerging chlorinated and brominated flame retardants. In total, 120 target compounds were analysed. For some analytes, comparisons of accumulation in moss and tree leave samples were possible.ResultsExcept for certain flame retardants, PFAS, and ndl-PCB, substances of all other compound classes could be quantified in moss samples of all sites. Concentrations were highest for PAH (40–268 ng g−1) followed by emerging flame retardants (0.5–7.7 ng g−1), polybrominated diphenyl ethers (PBDE; 0.3–3.7 ng g−1), hexabromocyclododecane (HBCD; 0.3–1.2 ng g−1), dl-PCB (0.04–0.4 ng g−1) and PCDD/F (0.008–0.06 ng g−1).ConclusionsResults show the widespread atmospheric distribution and deposition of organic contaminants across Germany as well as the suitability of moss as bioaccumulation monitor for most of these compound classes. Compared to nearby tree leaf samples, accumulation potential of moss appeared to be higher for pollutants of high octanol–air partition coefficient (KOA) and octanol–water partition coefficient (KOW).

Mapping percentile statistics of element concentrations in moss specimens collected from 1990 to 2015 in forests throughout Germany

Monitoring and mapping of atmospheric deposition can be achieved by use of chemical transport models, technical sampling devices and/or bio-accumulators such as mosses, lichens, etc. Within the European Moss Survey programme, since 1990 every 5 years mos specimens have been collected and analysed for heavy metals, nitrogen and persistent organic pollutants according a harmonised methodology. Calculation and geostatistical mapping of percentile statistics of element concentration in moss is in the focus of this paper. Thereby, element- and survey-specific as well as heavy metals and surveys integrating statistical evaluations and GIS-mapping were performed. Cr, Sb and Zn show contrary to Fe and Pb, no constant decrease of element concentrations, but an intermediate increase between 2000 and 2005, which did not continue until 2015. Cd, Hg, Pb and N which are of priority according to the Convention on Long-Range Transboundary Air Pollution are in focus in this paper. Additionally, Cr is regarded as representing those elements with an intermediate increase between the years 2000 and 2005 as is also true for Sb and Zn. Surveys integrating percentile statistics depict the spatial patterns of, in most cases, declining element concentrations across time. Survey-specific statistical analyses corroborate that the spatial patterns of element concentrations in moss are changing element-specifically across time. The long-term information on the percentile statistics of bioaccumulation of atmospheric deposition in moss is essential for further scientific evaluation as well as for measurements and reporting of nature protection and environmental management.

Site-specific investigation and spatial modeling of canopy drip effect on element concentrations in moss.

In this study, the canopy drip effect on the exposure of forests to atmospheric deposition of potentially toxic metals and nitrogen (N) and element accumulation was investigated. Thereby, the respective element concentrations of metals and N in moss specimens were investigated by example of North-Western Germany. To this end, on the one hand, the concentrations of Al, As, Cd, Cr, Cu, Fe, Hg, Pb, Ni, Sb, V, Zn, and N in mosses sampled under, outside, and at the edge of forest canopies were examined for statistical significant differences. On the other hand, vegetation structures parameterizing the canopy drip effect were quantified by use of information collected, in addition to the element data, at each moss sampling site. The statistical relations between ratios of vegetation parameters and ratios of element concentrations were modeled by regression analysis, and the respective element concentration in moss was geostatistically estimated and mapped for unsampled locations throughout Germany. This article tackles regression models with R2 > 0.5 (Cu, Hg, Pb, Sb, and N) to adapt the element concentrations measured at the 400 sites of the European Moss Survey (EMS) to three different features of hypothetical vegetation structures. To this end, the continuum of vegetation structures were represented as follows: open land (meadows) described by a leaf area index (LAI) value of 2.96 and under canopy sites in coniferous forests represented by a LAI value of 11. The arithmetic mean of LAI values at 400 EMS sites throughout Germany amounts to 5.1. The element concentrations for these target LAIs representing three site categories were calculated and mapped. Then, these LAI-dependent element concentration maps were compared with the maps depicting the spatial patterns of "pure" element concentrations. Spatial differences were evaluated and supposed to be of great value for the validation of atmospheric deposition modeling.

Moss biomonitoring of atmospheric deposition study of minor and trace elements in Macedonia

In the framework of the International Cooperative Program on Effects of Air Pollution on Natural Vegetation and Crops (UNECE ICP Vegetation), in 2002, 2005, and 2010, a moss biomonitoring technique was applied to air pollution studies in the Republic of Macedonia. А fourth moss survey took place in August and September 2015, when 72 samples of the terrestrial moss samples were collected over the territory of the country. Using inductively coupled plasma-atomic emission spectrometry (ICP-AES) and atomic absorption spectrometry (AAS), a total of 22 elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Rb, Sr, V, and Zn) were determined. By comparing the obtained values from all of the surveys, it can be concluded that almost all potentially toxic elements (As, Cd, Co, Cr, Cu, Ni, Pb, and Zn) increased in content in moss samples from 2002 to 2005 but decreased in the samples from 2010 to 2015. Increased values from 2005 to 2015 were observed for Cd and Pb, which is likely due to the reactivation of mining for lead and zinc in Eastern Macedonia, with large amounts of floatation tailings deposited in the landfills as well as due to the increased capacity of the ferronickel smelter near the city of Kavadarci. From data obtained in 2015, a factor analysis was performed to identify and characterize different pollution sources. Distributional maps for all elements were also prepared to point out the regions that were the most affected by anthropogenic activities. The survey conducted in 2015 showed that the situation with air pollution by potentially toxic metals in Macedonia is similar to that established in 2010. This is because all activities in the fields of mining and metallurgy were in continuous work with the same capacity during that five-year period. Still, the largest anthropogenic impact of air pollution with heavy metals established a smelter for ferronickel near Kavadarci (Ni and Cr) and lead and zinc mines in the vicinity of Probistip, Makedonska Kamenica, and Kriva Palanka (Cd, Pb, and Zn).

Inter-species and intra-annual variations of moss nitrogen utilization: Implications for nitrogen deposition assessment

Moss nitrogen (N) concentrations and natural 15N abundance (δ15N values) have been widely employed to evaluate annual levels and major sources of atmospheric N deposition. However, different moss species and one-off sampling were often used among extant studies, it remains unclear whether moss N parameters differ with species and different samplings, which prevented more accurate assessment of N deposition via moss survey. Here concentrations, isotopic ratios of bulk carbon (C) and bulk N in natural epilithic mosses (Bryum argenteum, Eurohypnum leptothallum, Haplocladium microphyllum and Hypnum plumaeforme) were measured monthly from August 2006 to August 2007 at Guiyang, SW China. The H. plumaeforme had significantly (P < 0.05) lower bulk N concentrations and higher δ13C values than other species. Moss N concentrations were significantly (P < 0.05) lower in warmer months than in cooler months, while moss δ13C values exhibited an opposite pattern. The variance component analyses showed that different species contributed more variations of moss N concentrations and δ13C values than different samplings. Differently, δ15N values did not differ significantly between moss species, and its variance mainly reflected variations of assimilated N sources, with ammonium as the dominant contributor. These results unambiguously reveal the influence of inter-species and intra-annual variations of moss N utilization on N deposition assessment.

Characterization of Heavy Metal Air Pollution in Romania Using Moss Biomonitoring, Neutron Activation Analysis, and Atomic Absorption Spectrometry

ABSTRACTHeavy metal air pollution in Romania was investigated by using passive moss biomonitoring. This study is a component of an international UNECE ICP Vegetation Program – moss survey. A total of 330 samples of Hypnum cupressiforme, Hylocomium splendens, Pleurozium schreberi, and other mosses were collected in Romania in the summer and autumn of 2010. The concentrations of aluminum, cadmium, chromium, copper, iron, lead, nickel, vanadium, and zinc were determined by graphite furnace/flame atomic absorption spectrometry and instrumental neutron activation analysis. The results were statistically processed to obtain spatial distribution maps of factor scores based on elemental concentrations in the moss, together with the spatial distribution maps of heavy metals in moss. The median concentrations of cadmium, 1.20 mg/kg dry weight, and lead, 30.8 mg/kg dry weight, were high compared with other European countries. The results revealed that the atmospheric deposition of these metals is a problem in north and northwest Romania.

Less-studied TCE: are their environmental concentrations increasing due to their use in new technologies?

The possible environmental impact of the recent increase in use of a group of technology-critical elements (Nb, Ta, Ga, In, Ge and Te) is analysed by reviewing published concentration profiles in environmental archives (ice cores, ombrotrophic peat bogs, freshwater sediments and moss surveys) and evaluating temporal trends in surface waters. No increase has so far been recorded. The low potential direct emissions of these elements, resulting from their absolute low production levels, make it unlikely that the increasing use of these elements in modern technology has any noticeable effect on their environmental concentrations on a global scale. This holds particularly true for those of these elements that are probably emitted in relatively high amounts from other human activities (i.e., coal combustion and non-ferrous smelting), such as In, the most studied element of the group.

Bioindication and modelling of atmospheric deposition in forests enable exposure and effect monitoring at high spatial density across scales

Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension. For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor. This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3). Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method. It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven. Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.

Modelling and mapping heavy metal and nitrogen concentrations in moss in 2010 throughout Europe by applying Random Forests models

ObjectiveThis study explores the statistical relations between the concentration of nine heavy metals (HM) (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), vanadium (V), zinc (Zn)), and nitrogen (N) in moss and potential explanatory variables (predictors) which were then used for mapping spatial patterns across Europe. Based on moss specimens collected in 2010 throughout Europe, the statistical relation between a set of potential predictors (such as the atmospheric deposition calculated by use of two chemical transport models (CTM), distance from emission sources, density of different land uses, population density, elevation, precipitation, clay content of soils) and concentrations of HMs and nitrogen (N) in moss (response variables) were evaluated by the use of Random Forests (RF) and Classification and Regression Trees (CART). Four spatial scales were regarded: Europe as a whole, ecological land classes covering Europe, single countries participating in the European Moss Survey (EMS), and moss species at sampling sites. Spatial patterns were estimated by applying a series of RF models on data on potential predictors covering Europe. Statistical values and resulting maps were used to investigate to what extent the models are specific for countries, units of the Ecological Land Classification of Europe (ELCE), and moss species. ResultsLand use, atmospheric deposition and distance to technical emission sources mainly influence the element concentration in moss. The explanatory power of calculated RF models varies according to elements measured in moss specimens, country, ecological land class, and moss species. Measured and predicted medians of element concentrations agree fairly well while minima and maxima show considerable differences. The European maps derived from the RF models provide smoothed surfaces of element concentrations (As, Cd, Cr, Cu, N, Ni, Pb, Hg, V, Zn), each explained by a multivariate RF model and verified by CART, and thereby more information than the dot maps depicting the spatial patterns of measured values. ConclusionsRF is an eligible method identifying and ranking boundary conditions of element concentrations in moss and related mapping including the influence of the environmental factors.

Reorganisation of a long-term monitoring network using moss as biomonitor for atmospheric deposition in Germany

The determination of atmospheric deposition in forests can be accomplished using technical sampling devices (bulk samplers, wet only samplers), biomonitors or modelling. In Europe, since 1990 moss sampled every five years at up to 7300 places in up to 35 countries was used as biomonitor. In the moss specimens, heavy metals (HM), nitrogen (N, since 2005) and persistent organic pollutants (POPs, since 2010) were determined. Germany participated in all surveys with the exception of that in 2010. For the moss survey 2015, the biomonitoring network applied in the 2005 campaign should be reorganized. To this end, a complex statistically based methodology including a decision support system was developed and implemented. Its application yielded a network with a reduction of sample points from 726 to 402. By use of the data collected in 2005 the performance of the reorganized network did not reveal significant loss of statistical validity.

Erratum to: Spatially valid data of atmospheric deposition of heavy metals and nitrogen derived by moss surveys for pollution risk assessments of ecosystems.

For analysing element input into ecosystems and associated risks due to atmospheric deposition, element concentrations in moss provide complementary and time-integrated data at high spatial resolution every 5 years since 1990. The paper reviews (1) minimum sample sizes needed for reliable, statistical estimation of mean values at four different spatial scales (European and national level as well as landscape-specific level covering Europe and single countries); (2) trends of heavy metal (HM) and nitrogen (N) concentrations in moss in Europe (1990-2010); (3) correlations between concentrations of HM in moss and soil specimens collected across Norway (1990-2010); and (4) canopy drip-induced site-specific variation of N concentration in moss sampled in seven European countries (1990-2013). While the minimum sample sizes on the European and national level were achieved without exception, for some ecological land classes and elements, the coverage with sampling sites should be improved. The decline in emission and subsequent atmospheric deposition of HM across Europe has resulted in decreasing HM concentrations in moss between 1990 and 2010. In contrast, hardly any changes were observed for N in moss between 2005, when N was included into the survey for the first time, and 2010. In Norway, both, the moss and the soil survey data sets, were correlated, indicating a decrease of HM concentrations in moss and soil. At the site level, the average N deposition inside of forests was almost three times higher than the average N deposition outside of forests.

Spatially valid data of atmospheric deposition of heavy metals and nitrogen derived by moss surveys for pollution risk assessments of ecosystems.

For analysing element input into ecosystems and associated risks due to atmospheric deposition, element concentrations in moss provide complementary and time-integrated data at high spatial resolution every 5years since 1990. The paper reviews (1) minimum sample sizes needed for reliable, statistical estimation of mean values at four different spatial scales (European and national level as well as landscape-specific level covering Europe and single countries); (2) trends of heavy metal (HM) and nitrogen (N) concentrations in moss in Europe (1990-2010); (3) correlations between concentrations of HM in moss and soil specimens collected across Norway (1990-2010); and (4) canopy drip-induced site-specific variation of N concentration in moss sampled in seven European countries (1990-2013). While the minimum sample sizes on the European and national level were achieved without exception, for some ecological land classes and elements, the coverage with sampling sites should be improved. The decline in emission and subsequent atmospheric deposition of HM across Europe has resulted in decreasing HM concentrations in moss between 1990 and 2010. In contrast, hardly any changes were observed for N in moss between 2005, when N was included into the survey for the first time, and 2010. In Norway, both, the moss and the soil survey data sets, were correlated, indicating a decrease of HM concentrations in moss and soil. At the site level, the average N deposition inside of forests was almost three times higher than the average N deposition outside of forests.