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In a publication in Atmospheric Environment ( http://dx.doi.org/10.1016/j.atmosenv.2015.10.081 ), Gu et al. (2015) estimated that “the total nitrogen (N) deposition in 2010 was 2.32 g N m −2 yr −1 ” in China. This value is comparable with previous estimations based on a synthesized dataset of wet/bulk inorganic N deposition observations, which underestimates the total N deposition since their algorithm (equations (2) and (3) in their paper) does not account for dry deposition of NH 3 , HNO 3 , NO x and wet/dry deposition of HONO and organic nitrogen (e.g. amines, amides, PAN). Indeed, Gu et al. (2015) mixed the terminology of wet/bulk deposition and total deposition. Another flawed assumption by Gu et al. (2015) is that all inorganic N in precipitation estimated by their algorithm originates from fertilizer and coal combustion. This is incorrect and almost certainly causes biases in the spatial and temporal distribution of estimated wet/bulk inorganic N deposition (Fig. 5 in their paper), further considering the fact that they neglected important N sources like livestock and they did not consider the nonlinearity between various sources and deposition. Besides the input data on N deposition, the model validation (Sect. 2.3.2) described in their paper also requires clarification because the detailed validation information about the time series of observational dataset versus modeling results was not given. As a result of these combined uncertainties in their estimation of N deposition and the lack of detail for model-measurement comparison, their estimates of the impacts of N deposition on carbon storage in Chinese forests may need further improvement. We suggest the clarification of the terminology regarding N deposition, especially for wet deposition, bulk deposition, gaseous and particulate dry deposition or total deposition since the accurate distinction between these terms is crucial to investigating and estimating the effects of N deposition on ecosystems. [ABSTRACT FROM AUTHOR]

The inorganic chemical composition (major ions and trace metals) of bulk deposition samples collected monthly with bulk collectors at seven Atlantic Coastal European cities (Galicia, Northwest of Spain) during wet season (September 2011 to March 2012) has been assessed and compared. Trace metals (Al, As, Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V and Zn) were analysed in soluble fraction and non-soluble fraction (after acid extraction) of the bulk deposition by inductively coupled plasma-mass spectrometry. Major inorganic ions (Cl, NO , SO , Na, K, Ca, Mg and NH ) were analysed in the soluble fraction of the bulk deposition by capillary zone electrophoresis. Univariate analysis (ANOVA and Multiple Range Test) according to the location of each sampling site was performed. Results also suggest a great influence of cleaner Atlantic air masses. After partition coefficients and enrichment factor estimation, similar sources could be assigned for the ionic and metal composition of bulk deposition at seven urban sites. [ABSTRACT FROM AUTHOR]

The complexing capacity for Cu ions ( L T ) and the apparent stability constant values (log K app ) were measured in throughfall (TF) and open field bulk deposition (BD), at two Mediterranean forest ecosystems of western Greece. L T was measured for the first time in the TF of natural forests. Concentrations of L T were three-to-four-fold higher in TF (mean ± st.dev: 2014 ± 769 nM for Varetada and 1565 ± 595 nM for Karpenissi) compared to those in BD (531 ± 517 nM and 468 ± 321 nM, respectively). In all TF and BD samples, L T concentrations were significantly higher than the corresponding total Cu concentrations, indicating that Cu was fully complexed. The L T /TOC ratios in TF were found comparable between the two study sites (235 ± 149 nM mg −1 C for Varetada and 256 ± 233 nM mg −1 C for Karpenissi) and with those of BD (226 ± 257 and 163 ± 163 nM mg −1 C, respectively). The determined mean log K app values were almost identical in TF (6.8 ± 0.7 at Varetada; 6.8 ± 0.6 at Karpenissi) and BD (6.5 ± 0.6 at Varetada; 6.8 ± 0.3 at Karpenissi), pointing to the fact that regardless of the enrichment of TF in ligands ( L T (TF) > L T (BD) ) the type of binding sites remain the same. The log K app values which were obtained herewith are similar to those obtained for humic-like substances (HULIS), indicating them as the most widespread type of ligands in BD and TF. [ABSTRACT FROM AUTHOR]

Concentrations of both gamma radionuclides as well as major ions in bulk deposition samples were measured monthly from January 2005-December 2013 and January 2007-December 2013 respectively. The gamma radionuclides present are Be, Pb and K (50 % of the samples), while ions in bulk deposition were dominated by Ca, Cl, $${\text{SO}}_{4}^{2 - }$$ and Na. Principal component analysis, enrichment factor and source assessment were performed to identify possible common sources. The time series of radionuclides and ions showed seasonal pattern and dependence mainly with number of African outbreaks, temperature and rain. Relatively poor correlations were observed between radionuclides and major ions. [ABSTRACT FROM AUTHOR]

Ten atmospheric bulk deposition (the sum of wet and dry deposition) samplers for polycyclic aromatic hydrocarbons (PAHs) were deployed at a plain-mountain transect (namely PMT transect, from Daying to Qingping) in Chengdu Plain, West China from June 2007 to June 2008 in four consecutive seasons (about every three months). The bulk deposition fluxes of ∑ 15 -PAHs ranged from 169.19 μg m −2 yr −1 to 978.58 μg m −2 yr −1 with geometric mean of 354.22 μg m −2 yr −1 . The most prevalent PAHs were 4-ring (39.65%) and 3-ring (35.56%) PAHs. The flux values were comparable to those in rural areas. Higher fluxes of total PAHs were observed in the middle of PMT transect (SL, YX and JY, which were more urbanized than other sites). The seasonal deposition fluxes in the sampling profile indicated seasonality of the contaminant source was an important factor in controlling deposition fluxes. PAHs bulk deposition was negatively correlated with meteorological parameters (temperature, wind speed, humidity, and precipitation). No significant correlations between soil concentrations and atmospheric deposition were found along this transect. PAHs in soil samples had combined sources of coal, wood and petroleum combustion, while a simple source of coal, wood and grass combustion for bulk deposition. There were significant positive correlation relationship (p < 0.05) between annual atmospheric bulk deposition and local PAHs emission, with biomass burning as the major contribution to the total emission of PAHs. This transect acts as an important PAHs source rather than being a sink according to the ratio of deposition/emission. Mountain cold trap effect existed in this transect where the altitude was higher than 1000 m. Long-range transport had an impact on the bulk deposition in summer. And this transect was a source to Tibetan only in summer. The forward trajectory analysis showed most air masses did not undergo long-range transport due to the blocking effect of surrounding mountains. Only a few air masses (<10%) arrived at the eastern and northern region of China or farther regions via long-range transport. [ABSTRACT FROM AUTHOR]

A systematic dataset of an observation network on a national scale has been organized to investigate the spatial distribution of bulk sulfur (S) deposition (S dep ) throughout China during 2000–2013, representing by far the most detailed data set to track the bulk sulfur deposition throughout China since 2000. Such a dataset is needed for ecosystem studies and for developing emission control policies. Bulk S dep values showed great variations, ranging from 2.17 to 70.55 kg ha −1 y −1 , with an average of 22.99 kg ha −1 y −1 . The average rate of bulk S dep located in East Coastal region (35.97 kg ha −1 y −1 ), Middle Yangtze region (57.90 kg ha −1 y −1 ), Middle Yellow River region (23.42 kg ha −1 y −1 ), North Coastal region (42.19 kg ha −1 y −1 ), Northeast region (34.28 kg ha −1 y −1 ), South Coastal region (36.97 kg S ha −1 y −1 ), Southwest region (33.85 kg ha −1 y −1 ) was 4.50, 7.24, 2.93, 5.28, 4.29, 4.63 and 4.24 times than that in Northwest region (7.99 kg ha −1 y −1 ). Bulk S dep over China was mainly from fossil fuel combustion (76.96%), biomass burning (7.64%), crust (6.22%), aged sea salt (5.48%) and agriculture (3.68%). A systematic observation network on a national scale should be established to conduct a long-term monitoring atmospheric S dep (including wet and dry deposition), based on exiting ecological stations administrated by different departments in China. [ABSTRACT FROM AUTHOR]

Doğal ve/veya antropojenik kaynaklardan atılan kirleticilerin atmosferde çeşitli süreçlerden geçtikten sonra tekrar yeryüzeyine dönmeleri atmosferik çökelme olarak tanımlanmaktadır. Kuru ve/veya ıslak olarak gerçekleşen atmosferik çökelme, giriş yaptığı su, bitki örtüsü, toprak, çeşitli tarihi ve diğer yapılar gibi ortamlara verdiği zararlardan dolayı son yıllarda ağırlıklı olarak çalışılan konulardan biridir. Ancak atmosferik çökelme tayini çok çeşitli ve değişken parametrelerin etkisinde olduğundan tespiti oldukça zordur ve çeşitli örnekleme cihazı ve örnekleme yüzeylerine ihtiyaç duyulmaktadır. Islak çökelme manuel veya otomatik kontrollü cihazlarla örneklenebilirken, kuru çökelmede, çeşitli meteorolojik ve topografik etkileri minimize etmek için örnekleme yüzeyleri kullanılmaktadır. Yapılan çalışmalar su yüzeyli örnekleyicilerin hem kuru hem de toplam (bulk) çökelmeyi örneklemede daha uygun olduğunu göstermektedir. Bu makalede, atmosferik çökelme olayı ve tayin yöntemleri özetlenmiş, çeşitli hava kirleticilerin çökelme akılarını belirlemek için geliştirilmiş toplama yüzeyleri birbirleriyle kıyaslanmıştır.

Doğal ve/veya antropojenik kaynaklardan atılan kirleticilerin atmosferde çeşitli süreçlerden geçtikten sonra tekrar yeryüzeyine dönmeleri atmosferik çökelme olarak tanımlanmaktadır. Kuru ve/veya ıslak olarak gerçekleşen atmosferik çökelme, giriş yaptığı su, bitki örtüsü, toprak, çeşitli tarihi ve diğer yapılar gibi ortamlara verdiği zararlardan dolayı son yıllarda ağırlıklı olarak çalışılan konulardan biridir. Ancak atmosferik çökelme tayini çok çeşitli ve değişken parametrelerin etkisinde olduğundan tespiti oldukça zordur ve çeşitli örnekleme cihazı ve örnekleme yüzeylerine ihtiyaç duyulmaktadır. Islak çökelme manuel veya otomatik kontrollü cihazlarla örneklenebilirken, kuru çökelmede, çeşitli meteorolojik ve topografik etkileri minimize etmek için örnekleme yüzeyleri kullanılmaktadır. Yapılan çalışmalar su yüzeyli örnekleyicilerin hem kuru hem de toplam (bulk) çökelmeyi örneklemede daha uygun olduğunu göstermektedir. Bu makalede, atmosferik çökelme olayı ve tayin yöntemleri özetlenmiş, çeşitli hava kirleticilerin çökelme akılarını belirlemek için geliştirilmiş toplama yüzeyleri birbirleriyle kıyaslanmıştır.

Bulk precipitation were collected in 6 stations located în forest ecosystems from north and south Romania, during 1998-2002. Samples were analysed in the laboratory for pH and the major anions and cations. For the 3 stations in the north only data from 1998 to 2001 were completed. The fluxes of mineral ions in bulk deposition measured in 2002 for the 3 stations located in south Romania were compared to the means determined in 1998-2001. The inputs decreased for S-SO4 2- ( 19-25 %), N-NO3 - ( 29-73%) and Cl- (cu 9-10%). For H+ , N-NH4 + , Na and K+ no trends were clearly observed. Ca2+ and Mg2+ fluxes in bulk deposition decresed in 2002 with 39-66% and respectivly 31- 78% related to 1998-2001. Comparison of the mean ions fluxes registred in the north and south Romania during 1998-2001 revealed that excepting for H+ and Cl- , which were higher in north than in south, for all the other ions the values determined in north were equal (N-NO3 - ) or lower (S-SO4 2-, N-NH4 + , K+ , Mg2+, Ca2+) than those measured in the south part of Romania. Values of mineral ions inputs registred in Romania from 1998 to 2002 were compared to those calculated in some zones of Europe from 1993 to 1998. Fluxes of H+ , Cland Na+ were relatevly low compared to those form Europe. The SSO4 2- fluxes were moderate and high and the NNH4 + , K+ , Mg2+, Ca2+ were high în Romania related to those determined in Europe.

In order to assess how environmental factors are affecting the distribution and migration of radioiodine and plutonium that were emitted from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, we quantified iodine and 239,240 Pu concentration changes in soil samples with different land uses (urban, paddy, deciduous forest and coniferous forest), as well as iodine speciation in surface water and rainwater. Sampling locations were 53–63 km northwest of the FDNPP within a 75-km radius, in close proximity of each other. A ranking of the land uses by their surface soil (<4 cm) stable 127 I concentrations was coniferous forest > deciduous forest > urban > paddy, and 239,240 Pu concentrations ranked as deciduous forest > coniferous forest > paddy ≥ urban. Both were quite distinct from that of 134 Cs and 137 Cs: urban > coniferous forest > deciduous forest > paddy, indicating differences in their sources, deposition phases, and biogeochemical behavior in these soil systems. Although stable 127 I might not have fully equilibrated with Fukushima-derived 129 I, it likely still works as a proxy for the long-term fate of 129 I. Surficial soil 127 I content was well correlated to soil organic matter (SOM) content, regardless of land use type, suggesting that SOM might be an important factor affecting iodine biogeochemistry. Other soil chemical properties, such as Eh and pH, had strong correlations to soil 127 I content, but only within a given land use (e.g., within urban soils). Organic carbon (OC) concentrations and Eh were positively, and pH was negatively correlated to 127 I concentrations in surface water and rain samples. It is also noticeable that 127 I in the wet deposition was concentrated in both the deciduous and coniferous forest throughfall and stemfall water, respectively, comparing to the bulk rainwater. Further, both forest throughfall and stemflow water consisted exclusively of organo-iodine, suggesting all inorganic iodine in the original bulk deposition (∼28.6% of total iodine) have been completely converted to organo-iodine. Fukushima-derived 239,240 Pu was detectable at a distance ∼61 km away, NW of FDNPP. However, it is confined to the litter layer, even three years after the FDNPP accident-derived emissions. Plutonium-239,240 activities were significantly correlated with soil OC and nitrogen contents, indicating Pu may be associated with nitrogen-containing SOM, similar to what has been observed at other locations in the United States. Together, these finding suggest that natural organic matter (NOM) plays a key role in affecting the fate and transport of I and Pu and may warrant greater consideration for predicting long-term stewardship of contaminated areas and evaluating various remediation options in Japan. [ABSTRACT FROM AUTHOR]

Deposition of dissolved organic nitrogen (DON) in both bulk precipitation (BD) and canopy throughfall (TF) has been measured for the first time in the western Mediterranean. The study was carried out over a year from 2012 to 2013 at four evergreen holm oak forests located in the Iberian Peninsula: two sites in the Province of Barcelona (Northeastern Spain), one in the Province of Madrid (central Spain) and the fourth in the Province of Navarra (Northern Spain). In BD the annual volume weighted mean (VWM) concentration of DON ranged from 0.25 mg l −1 in Madrid to 1.14 mg l −1 in Navarra, whereas in TF it ranged from 0.93 mg l −1 in Barcelona to 1.98 mg l −1 in Madrid. The contribution of DON to total nitrogen deposition varied from 34% to 56% in BD in Barcelona and Navarra respectively, and from 38% in Barcelona to 72% in Madrid in TF. Agricultural activities and pollutants generated in metropolitan areas were identified as potential anthropogenic sources of DON at the study sites. Moreover, canopy uptake of DON in Navarra was found in spring and autumn, showing that organic nitrogen may be a supplementary nutrient for Mediterranean forests, assuming that a portion of the nitrogen taken up is assimilated during biologically active periods. [ABSTRACT FROM AUTHOR]

Malathion is an organophosphate insecticide registered for use in cities throughout North America to control adult mosquitoes. The objective of this study was to determine the impact of urban malathion applications on the levels of malathion detected in bulk deposition. In 2010, malathion was applied by the City of Winnipeg's Insect Control Branch for a total amount of 6632 kg in the city, as well as by the general public in relatively small amounts. In 2011, no malathion was applied by the city. Malathion was detected in 41 % of the samples in 2010 with deposition rates ranging from 0.5 to 107.7 μg/m/week. Only 9 % of the samples contained malathion in 2011 with deposition rates always being <0.4 μg/m/week. Between 6 and 25 % of the samples in 2010 exceeded the toxicological threshold levels of malathion to a range of freshwater amphipods, water fleas, and stoneflies, including Daphnia magna which is a bioindicator of good environmental health. The weekly maximum malathion concentration detected in this study (5.2 μg/L for a week in June 2010) was at least 26 times greater than the maximum concentration of malathion reported in other atmospheric deposition studies. For the two insect management areas (7.4 and 37.6 km) where the bulk deposition samplers had been placed, calculations suggested that between 1.2 and 5.1 % of the malathion applied by the city became bulk deposition. Percutaneous absorption by humans of malathion in rainfall is unknown. [ABSTRACT FROM AUTHOR]

Atmospheric inputs of N and S in bulk deposition (open collectors) and throughfall (beneath canopy collectors) were measured in and adjacent to two Class 1 wilderness areas of the northeastern US. In general, atmospheric S inputs followed our expectations with throughfall S fluxes increasing with elevation in the White Mountains, New Hampshire and throughfall S fluxes being greater in coniferous than deciduous stands in both sites. In contrast, throughfall N fluxes decreased significantly with elevation. Throughfall NO fluxes were greater in coniferous than deciduous stands of Lye Brook, Vermont, but were greater in deciduous than coniferous stands of the White Mountains. We found overlap in the range of values for atmospheric N inputs between our measurements and monitoring data [National Atmospheric Deposition Program (NADP) and Clean Air Status and Trends Network (CASTNET)] for wet and total (wet + dry) deposition at Lye Brook. However, our measurements of total S deposition in the White Mountains and bulk (wet) deposition at both Lye Brook and the White Mountains were significantly lower than NADP plus CASTNET, and NADP data, respectively. Natural abundance O in throughfall and bulk deposition were not significantly different, suggesting that there was no significant biological production of $${\text{NO}}_{3}^{ - }$$ via nitrification in the canopy. NO concentrations in streams were low and had natural abundance O values consistent with microbial production, demonstrating that atmospheric N is being biologically transformed while moving through these watersheds and that these forested watersheds are unlikely to be N saturated. [ABSTRACT FROM AUTHOR]

Bulk deposition can remove atmospheric organic and inorganic pollutants that may be associated with gaseous, liquid or particulate phases. To the best of our knowledge, few studies have been carried out, which simultaneously analyse the presence of organic and inorganic fractions in rainwater. In the present work, the complementarity of organic and inorganic data was assessed, through crossing data of some organic [DOC (dissolved organic carbon), absorbance at 250 nm (UV 250nm ), integrated fluorescence] and inorganic [H+, NH4+ , NO 3- , non sea salt sulphate (NSS-SO 42- )] parameters measured in bulk deposition in the coastal urban area of Aveiro. The organic and inorganic parameters analysed were positively correlated ( p < 0.001) except for H+ , which suggests that a constant fraction of chromophoric dissolved organic matter (CDOM) came from anthropogenic sources. Furthermore, the inverse correlations observed for the organic and inorganic parameters with the precipitation amount suggest that organic and inorganic fractions were incorporated into the rainwater partially by below-cloud scavenging of airborne particulate matter. This is in accordance with the high values of DOC and NO 3- found in samples associated with marine air masses, which were linked in part to the contribution of local emissions from vehicular traffic. DOC of bulk deposition was the predominant constituent when compared with the constituents H+ , NH4+ , NO 3 - and NSS-SO 4 2- , and consequently bulk deposition flux was also highest for DOC, highlighting the importance of DOC and of anthropogenic ions being simultaneously removed from the atmosphere by bulk deposition. However, it was verified that the contribution of anthropogenic sources to the DOC of bulk deposition may be different for distinct urban areas. Thus, it is recommended that organic and inorganic fractions of bulk deposition are studied together. [ABSTRACT FROM AUTHOR]

To characterize the atmospheric content of chemical contaminants, samples of atmospheric deposits were collected at several sites in the mining area of the San Jorge river basin, Colombia, during La Niña events (May 2010 and October 2011). Measurements of trace metals (Hg, Cu, Cd, Pb, Ni, and Zn) were performed after rain collection using a bulk deposition sampler in locations near a point source and sampling points located within a range of 30 Km away from the mine. As expected, concentrations were elevated in locations close to the ferronickel mining area with similar levels to other highly polluted areas. Concentrations of bulk precipitation and deposition were measured for Zn (23.07 ± 7.30 ng mL and 227.5 ± 22.3 μg m day, respectively) and Ni (2.20 ± 1.35 ng mL and 21.2 ± 4.79 μg m day) close to the coal and ferronickel mining. The other metals showed higher concentrations in sites nearby the artisanal and small-scale gold mining communities; and mercury raises special concern because high values of bulk deposition were found (58.3 ± 4.4 μg m day), suggesting an intense Hg exposure in local residents. Moreover, no patterns of temporal distribution of heavy metals deposition were found during the sampling period. Overall, these results suggest that trace metal concentrations and fluxes are comparable to other locations in the world that are impacted by regional anthropogenic sources related to mining activities. [ABSTRACT FROM AUTHOR]

Atmospheric deposition to forests has been monitored within the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) with sampling and analyses of bulk precipitation and throughfall at several hundred forested plots for more than 15 years. The current deposition of inorganic nitrogen (nitrate and ammonium) and sulphate is highest in central Europe as well as in some southern regions. We compared linear regression and Mann-Kendall trend analysis techniques often used to detect temporal trends in atmospheric deposition. The choice of method influenced the number of significant trends. Detection of trends was more powerful using monthly data compared to annual data. The slope of a trend needed to exceed a certain minimum in order to be detected despite the short-term variability of deposition. This variability could to a large extent be explained by meteorological processes, and the minimum slope of detectable trends was thus similar across sites and many ions. The overall decreasing trends for inorganic nitrogen and sulphate in the decade to 2010 were about 2% and 6%, respectively. Time series of about 10 and 6 years were required to detect significant trends in inorganic nitrogen and sulphate on a single plot. The strongest decreasing trends were observed in western central Europe in regions with relatively high deposition fluxes, whereas stable or slightly increasing deposition during the last 5 years was found east of the Alpine region as well as in northern Europe. Past reductions in anthropogenic emissions of both acidifying and eutrophying compounds can be confirmed due to the availability of long-term data series but further reductions are required to reduce deposition to European forests to levels below which significant harmful effects do not occur according to present knowledge. [ABSTRACT FROM AUTHOR]

In order to assess the influence of local environment and spatial integration of Trace Metals (TM) by biomonitors, Al, As, Cd, Cr, Cs, Cu, Fe, Mn, Ni, Pb, Sb, Sn, V and Zn and some rare earth element (REE) concentrations have been measured in lichens and mosses collected in three French forest sites located in three distinct mountainous areas, as well as in the local soil and bedrock, and in both bulk deposition (BD) and throughfall (TF). Similar enrichment factors (EF) were calculated using lichens and mosses and local bedrock for most elements, except for Cs, Mn, Ni, Pb, and Cu which were significantly (KW, p < 0.05) more enriched in mosses. Similar REE ratios were measured in soils, bedrock, lichens and mosses at each study sites, indicating a regional integration of atmospheric deposition by both biomonitors. Both TM signature and REE composition of mosses revealed that this biomonitor is highly influenced by throughfall composition, and reflect atmospheric deposition interaction with the forest canopy. This explained the higher enrichment measured in mosses for elements which concentration in deposition were influenced by the canopy, either due to leaching (Mn), direct uptake (Ni), or dry deposition dissolution (Pb, Cu, Cs). [ABSTRACT FROM AUTHOR]

Abstract: With planned expansion of oil sands facilities, there is interest in being able to characterize the magnitude and extent of deposition of metals and polycyclic aromatic hydrocarbons (PAH) in the Athabasca Oil Sands Region (AOSR) of Alberta. A study was undertaken using a bulk collection system to characterize wintertime atmospheric deposition of selected inorganic and organic contaminants in the AOSR. The study was carried out from January to March 2012 at two sampling sites near (within a 20km circle of oil sands development) and two sampling sites distant (>45km) to oil sands development. Triplicate bulk samplers were used to estimate precision of the method at one distant site. Monthly deposition samples were analyzed for 36 metals, ultra-low mercury, and 25 PAHs (including alkylated, and parent PAH). At the two sites located within 20km of oil sands development, 3-month wintertime integrated deposition for some priority metals, alkylated and parent PAH were higher compared to distant sites. Deposition fluxes of metals and PAH were compared to other available bulk deposition studies worldwide. Median bulk measurement uncertainties of metals and both PAH classes were 26% and within ±15%, respectively suggesting that the bulk sampling method is a potential alternative for obtaining future direct measures of wintertime metals and PAH deposition at locations without access to power in the AOSR. [Copyright &y& Elsevier]

Green roofs are increasingly used as sustainable urban drainage systems due to their retention and detention capacity; however, the impact of green roofs in term of water quality is still a debated issue among researchers. A monitoring programme was carried out at the University of Genoa on a full-scale experimental site to assess the quality of storm water outflows. As for rainfall, the bulk deposition (dry and wet fractions) is collected to evaluate the role of the overall atmospheric deposition in altering storm water quality. The pollutant load observed in the green roof outflow is limited; concentration values for solids and metals are lower than those generally observed in storm water runoff from impervious surfaces. Suspended solids and Chemical Oxygen Demand (COD) are below respectively 10 and 20 mg/l, on average; as for heavy metals, copper and zinc are equal to 30 μg/l on average, while iron is equal to 120 μg/l. The Event Mean Concentration (EMC) statistics of the pollutant loads associated with the rainfall and outflow have been compared and discussed. The observed green roof behaviour as a sink/source of pollutants with respect to the atmospheric deposition is also investigated based on both concentration and mass. Results demonstrate that: green roof behaves as a source with respect to solids, COD and potassium while zinc and mainly copper are retained within the green roof stratigraphy. The resulting mass delivery behaviour reveals that no significant first flush occurs for pollutant constituents irrespective of the hydrologic characteristics and pollutant sources. [ABSTRACT FROM AUTHOR]

Abstract: Bulk deposition of 68 elements was monitored for a period of 10 years at two rural stations in eastern Denmark. The deposition of 50 elements was documented based on concentrations well over the detection limit and with relatively small year to year variations. Eighteen elements were determined on a semi-quantitative basis. Fourteen elements, traditionally monitored in the Danish and Swedish national networks, were compared with the present results. The abundance of elements in bulk deposition was compared to the abundance of elements in soil dust, biogenic material and elements abundant in industrial emissions were discussed. [Copyright &y& Elsevier]

About 120 rainwater samples were collected through a network of five bulk collectors in the area of the Louros basin (Epirus, Greece) during the wet season from October 2008 to August 2009. They were analysed for their isotopic (δD and δ18O) and chemical (H+, Na+, K+, Mg2+, Ca2+, NH4 +, F−, Cl−, Br−, NO3 −, SO4 2−) composition. A local meteoric water line (δD‰=5.80±0.02 δ18O‰+0.02±0.12) and a local isotopic lapse rate (−0.18 δ18O‰/100m) were obtained considering the volume-weighted means of the five sampling sites. These results agree well with those obtained in nearby areas. The chemical composition of the samples allows to identify an almost entirely marine origin for chloride and sodium with decreasing deposition values at increasing distance from the coast. Nitrate and ammonium are almost completely of anthropogenic origin, calcium and potassium are overwhelmingly geogenic, sulphate has a prevailingly anthropogenic origin with a significant marine contribution and magnesium has a mixed marine and soil dust origin. Finally, as for most of the Mediterranean area, rainwater acidity is buffered by the dissolution of the abundant geogenic carbonate aerosol. [ABSTRACT FROM AUTHOR]

Since 2007, the University of Genoa has been carrying out a monitoring programme to investigate the hydrologic response of green roofs in the Mediterranean climate by installing a green roof experimental site. In order to assess the influence of green roofs on the storm water runoff quality, water chemistry data have been included in the monitoring programme since 2010, providing rainfall and outflow data. For atmospheric source, the bulk deposition is collected to evaluate the role of the overall atmospheric deposition in storm water runoff quality. For subsurface outflow, a maximum of 24 composite samples are taken on an event basis, thus aiming at a full characterization of the outflow hydrograph. Water chemistry data reveal that the pollutant loads associated with green roof outflow is low; in particular, solids and metal concentrations are lower than values generally observed in storm water runoff from traditional rooftops. The concentration values of chemical oxygen demand, total dissolved solids, Fe, Ca and K measured in the subsurface outflow are significantly higher than those observed in the bulk deposition (p<0.05). With respect to the atmospheric deposition, the green roof behaviour as a sink/source of pollutants is investigated based on both concentration and mass. [ABSTRACT FROM AUTHOR]

This study is the first to investigate the mineral composition of the atmospheric particulate matter deposited at Rio Tinto, Spain, an historical mining district of world-class importance, with emphasis on metal-bearing particles and their environmental implications. The dustfall is composed of quartz, feldspars, phyllosilicates (mica, chlorite and/or kaolinite) and a variety of accessory heavy minerals, the most common being primary sulfides (pyrite, chalcopyrite with minor galena, sphalerite and bornite) and their oxidation products (notably goethite, hematite and jarosite). This mineral assemblage suggests a local source of wind-blown dust and it is consistent with the large deposition levels of sulfide-related elements (As, Bi, Cd, Cu, Pb, Sb and Zn) registered at the sampling site adjacent to the mine waste dumps. However, the generation of potentially harmful dust particles is not restricted to mine wastes. Anthropogenic metallic compounds arising from a nearby hazardous waste disposal centre can make a relevant additional contribution to the metal deposition, particularly for Fe, Ni, Cr and Mn. Atmospheric fallout is a major mechanism for metal input to soils and plants around or near the mining area. [ABSTRACT FROM AUTHOR]

Abstract: In order to assess the contribution of a Municipal Solid Waste incinerator to the area's total contamination, metals and soluble ions have been determined in bulk deposition collected at sites affected by different levels of plant emissions, according to the results of the Calpuff air dispersion model. Results show that in general fluxes monitored at the different sites during the same period are quite similar for each analyte. Deposition fluxes of nitrite and ammonium are significantly lower at the more distant site, while copper is significantly higher at this site, possibly because of copper fungicide used on the nearby agriculture land. The presence of sea spray and resuspended soil dust can be inferred from Pearson correlation coefficients, while enrichment factors indicate that Cu, Pb and Zn have a probable anthropogenic origin. A more complete evaluation of the sources affecting the area was obtained with PMF analysis. The sources associated with each factor were identified from the source profile and temporal trends. Six factors were identified, three sources associate with natural matrices, while three factors represent anthropogenic sources. The greatest contribution of heavy metals, the most toxic and persistent components determined, is associated with resuspended soil dust, especially when weighted according to their toxicity. The anthropogenic source contribution is similar at all sites, and therefore the incinerator's relative contribution to the total pollutant load appears to be negligible compared to other sources affecting the area. [Copyright &y& Elsevier]

Abstract: Atmospheric deposition of lead (Pb), zinc (Zn) and cadmium (Cd) was investigated near the former Black Angel Pb–Zn mine in Maarmorilik, West Greenland during 2010–2011. Thalli of the lichen Flavocetraria nivalis were transplanted from an uncontaminated site into sites near the mine and collected the following year. At 20 of the total 21 sites, concentrations of Pb, Zn and Cd were significantly elevated in lichens after 1 year of transplantation compared to initial concentrations. Elevated concentrations were observed within a distance of approx. 20km from the mining area. Concentrations decreased with increasing distance from the mine and the relation was well described using a power function with a negative exponent (r 2 =0.90; 0.83 and 0.83 for Pb; Zn and Cd). To examine the relation between metal concentrations/uptake in lichen transplants and atmospheric bulk deposition, 10 Bergerhoff dust samplers were placed near lichen transplants and samplers and lichens were collected after a 7-weeks exposure period. A significant linear correlation was observed between metal concentrations in lichen transplants and atmospheric bulk metal deposition (r 2 =0.94; 0.88 and 0.89 for Pb; Zn and Cd). Combining the results and including an area distribution within a defined metal deposition area, the “annual” deposition of Pb, Zn and Cd as dust was estimated during the 2010–2011 snow-free period (∼5months). The results reveal that 20years after mine closure, 770kg Pb, 3700kg Zn and 24kg Cd were still being deposited as dust per year (snow-free period only) within a distance of 20km from the mine. [Copyright &y& Elsevier]

Samples of Flavoparmelia caperata (L.) Hale thalli, from a clean area in northern Portugal (Baião), were transplanted into exposure locations at the western Atlantic coast (north, center and south) impacted by urban-industrial emissions and meteorologically different, for a ten-month long experiment split into five terms of assessment (two months each). Through the experiment, the sites were also monitored for atmospheric bulk deposition. Analytical techniques for determinations in lichens and bulk deposition were instrumental neutron activation analysis, atomic absorption spectrophotometry and inductively coupled plasma mass spectrometry. The results indicate that: (1) the biological signals of detached lichens are compatible with sources in the area; (2) there is an appreciable number of airborne elements significantly enriched in (exposed) lichen samples, including some of great environmental interest; and (3) the cumulative contents per unit area of detached-lichen material are likely to provide an acceptable estimate of the atmospheric availability of enriched elements, as measured by their cumulative contents in the dry residues of bulk deposition. [ABSTRACT FROM AUTHOR]

Abstract: Chemical and radioactive composition of bulk deposition samples, which were collected monthly over a 5 year period (January 2007 until 31 December 2011) at a site located 30 m.a.l. in Málaga (4°28′ 8″W; 36°43′ 40″N) have been analysed. All samples were analysed for pH, major ions and gamma radionuclides. The average pH of bulk deposition was 6.4. Cl− and were the main anions, while Ca+ and Na+ were the main cations. Significant correlations were found in soil-derived species among Ca2+, Mg2+ and K+ and sea-salt species between Na+ and Cl−. Other relatively good correlations were also observed between acidic anions and crustal-derived cations (Ca2+, Na+, K+). Sources of the major ions were assessed based on the enrichment factor method. The radionuclides present in all samples are 7Be and 210Pb and 40K appears in 50% of the samples. Relatively poor correlations were observed between the specific activities of gamma radionuclides and the major ions. The temporal variations of major ions and radionuclides exhibit similar seasonal behaviour with low values in winter–autumn months and maximum values in spring–summer months. The fluxes of major ions and gamma radionuclides have been discussed with meteorological factors controlling depositions. [Copyright &y& Elsevier]

Wet-only, dry-only, bulk deposition and deposition of sedimentary particles and gases deposited after the last rain (DAR) were collected weekly at La Castanya station in the Montseny mountains (NE Spain, 41°46′N, 2°21′E) from February 2009 to July 2010. These samples were analysed for pH, alkalinity, and the concentrations of major ions (Cl, NO, SO, Na, K, Ca, Mg, NH). Significant differences were observed between bulk and wet-only precipitation, with an enrichment of ions associated to coarse particles in bulk deposition. The comparison between wet and dry fluxes revealed that the removal of compounds at Montseny occurred mainly by wet deposition, which accounted for 74 % of total deposition. The dry flux was characterised by the predominance of K, Ca and Mg, which are related to coarse particles. Bulk collection methods at Montseny were considered representative of total atmospheric deposition, since bulk deposition plus DAR accounted for 97 % of total deposition measured with wet and dry-only collection devices. Thus, bulk deposition collectors can be recommended for deposition networks at remote sites (lacking electricity connection) in environments, where coarse particles are a predominant fraction of the aerosol mass. [ABSTRACT FROM AUTHOR]