Dry Atmospheric Contribution to the Plant–Soil System Around a Cement Factory: Spatial Variations and Sources—a Case Study from Oman

The present study determines the source of dust particles and investigates their impact on the chemical compositions of plants and soils around a cement factory in Oman within a radius of 10 km of this disturbed ecosystem. A total number of nine samples of the species of plants (Rhazya stricta), nine samples of soils, and nine samples of dust were collected and analyzed for major ions and trace elements including rare earth elements (REEs). Principal component analysis applied to the major and trace element concentrations in the dust indicated the input of at least two sources to the dust in the study area: ophiolites and cement. The REE distribution in the plants and soils revealed that the most available elements to plants originated dominantly from ophiolites rather than from cement. The contribution of cement industry is significant only in the zone located at about 0.500 to 2 km around the cement factory, whereas the contribution of ophiolites increases with distance from the cement factory.     

Characterization of Cement Plant Emissions in Turkey

In cement plants in Turkey CO, NO₂, SO₂ and particulate emissions were measured using standard measurement techniques and equipment. Emission factors are calculated by dividing the emission rates by capacity of production at the time of measurements for each plant. The results of this study show that the dominant emissions from cement production in Turkey is CO followed by NO₂, dust and SO₂ in decreasing order. National averages for the emission factors are calculated and compared to international emission factors. On average the Turkish dust emission factor is higher than the German factor, however NO₂ and SO₂ emission factors are lower in Turkey.     

Growth of wheat plants exposed to cement dust pollution

Cement dust in the environment poses a threat to the proper functioning of plants in the vicinity of cement factories,as apparent from a field study conducted at different locations in the environs of Churk Cement Factory in Mirzapur District, U.P. Plant samples were collected at 100, 500, 1000, 1500, 2000, and 4000 m northeast of the factory, at three successive stages of plant growth The plant samples collected at 4000 m distance were treated as control, as there was no apparent deposition of cement dust on their surface. The samples were analyzed with respect to foliar injury symptoms, chlorophyll concentration and phytomass accumulation. Only plants closest to the factory displayed symptoms of foliar injury. The results reveal that wheat plants at polluted sites contained decreased concentration of chlorophyll in their leaves and had reduced accumulation of phytomass, as compared to control. The grains obtained from affected sites showed quantitative and qualitative deterioration. Physico-chemical properties of the soils at polluted sites also underwent some undesirable changes. These effects had negative correlation with the distance from the factory.     

Reaction of CO2 with clean coal technology ash to reduce trace element mobility

The combustion of coal in power plants generates solids (e.g., fly ash, bottom ash) and flue gas (e.g., SO _x , CO₂). New Clean Air Act mandated reduction of SO _x emissions from coal burning power plants. As a result, a variety of Clean Coal Technologies (CCT) are implemented to comply with these amendments. However, most of the CCT processes transfer environmentally sensitive elements (e.g., As, Cd, Pb, Se) from flue gas to CCT ash. The objective of this study was to determine the effect of a pressurized CO₂ treatment on the chemistry of CCT ash. Three CCT ash samples, produced from lime injection, atmospheric fluidized bed combustion, and sodium carbonate injection processes were reacted under different CO₂ pressure treatment conditions. Treated and untreated samples were subjected to various experiments including, X-ray diffraction (XRD) analysis, calcium carbonate solubility studies, and trace element extraction studies. Factors influencing the efficiency of a CO₂ treatment for CCT ash samples include combustion process, moisture, CO₂ concentration, and pressure. The CO₂ pressure treatment resulted in the precipitation of calcite in CCT ash samples, and thus lowered the pH and the concentration of extractable trace elements (e.g., Cd, Pb, Cr, As, Se). Furthermore, we found that CO₂ pressure treatment was more effective for lime injection and atmospheric fluidized bed combustion processed samples than for sodium carbonate injection processed samples.     

Case studies of Asian dust storm impacts on a coastal site: implication of a good dust storm tracer

Significant dust storm impacts have seldom been recorded and reported in Hong Kong. Herein, four cases which occurred in Hong Kong during the spring times of recent years are examined using back-trajectory computation and chemical analysis of air-borne samples. All of the cases show that the dust was transported from the source to Hong Kong in 2–5 days and that PM₁₀ concentrations approached or exceeded the European Union air quality criteria and the USA National Ambient Air Quality Standard. The chemical characteristics of the samples taken in these events agreed both with those from the source regions and with those archived from selected Hong Kong datasets. The concentrations of the crustal constituents (Al, Fe, Mn, Ca) of the Hong Kong samples on the episode days were at least three times higher than the concentrations measured on non-episode days. The mass ratios of Fe/Al and Mn/Al (but not Ca/Al) can act as good tracers of Asian dust storms to this coastal site where sea-salt and other anthropogenic species are normally dominant. Furthermore, unusually high Mg levels indicated a mainly crustal origin for this element, rather than the marine origin normally found at this coastal location. Particulate nitrate exhibited more elevated concentrations in all of the dust storm samples than in non-dust-storm and local samples.     

The Effects of Lithology on Water Pollution: Natural Radioactivity and Trace Elements in Water Resources of Eskisehir Region (Turkey)

The high radioactivity and trace elements in drinking water are common concerns for human health. The aim of this study was to investigate the eligibility of groundwater for drinking purpose in terms of both radioactivity and trace element contents in Eskisehir Region (Turkey). The study area is located in a highly populated residential area where water supply is mostly met from groundwater. The area is about 20,000 km², where igneous, metamorphic, and sedimentary rocks are exposed. The 209 water samples collected from 84 water resources (including thermal waters) were analyzed with respect to major ions, trace elements, and radioactivity (gross alpha and gross beta) during both in wet and dry seasons. Based on the analysis results, trace elements in 49 samples of 84 water resources were over the limits of Code TS 266 1997 (Turkish Drinking Water Standards) and WHO 1993 standards. Particularly, Fe, Mn, Al, As, Ba, Zn, Cr, Cu, and B ion concentrations exceeded the limits. The gross alpha values in 18 locations and gross beta values in three locations also exceeded the limits of aforementioned standards in terms of radioactivity (gross alpha?=?0.1 Bq L^?1; gross beta?=?1 Bq L^?1). Furthermore, water radioactivity levels were close to the allowable limits in 33 water resources. The obtained results explicitly indicate that there is a strong relationship between the higher radioactivity–trace element contents and geochemical composition of rocks, which controls the radioactivity and trace element concentrations present in the aquifer.     

Long range transport and deposition of mineral matter as a source for base cations

Mineral dust in the atmosphere is generally alkaline, and is a source of base cations in precipitation. Annual emissions of particles from large combustion plants and industrial processes in Europe is of the order of 24 million tonnes, and the calcium content may be as high as 1.4 million tonnes. Emissions from diffuse sources such as agricultural activities, construction and quarrying are much less well known. Emissions of dust from the Sahara have been estimated to more than 200 tonnes, with a calcium content of 3–5%. In northern Europe, airborne concentrations of calcium and the concentration of calcium in precipitation are generally consistent with the anthropogenic emissions and their regional distribution. Transport of dust from Sahara is a major source of base cations in precipitation around the Mediterranean Sea, but the influence diminishes further north. The concentration of calcium in precipitation decreases from south to north and from east to west in Europe. Dry deposition of alkaline particles is not well documented, but may be at least as high as the input by precipitation in regions where there are large emissions. There are still large uncertainty gaps with respect to emissions, transport and deposition of calcium-containing particles.     

Elemental deposition downwind of a coal-fired power plant

Dry deposition of fly ash emitted by a coal-fired power plant has been calculated using a surface depletion Gaussian plume model. The subject plant is located in the southwestern United States. Soil samples collected downwind of this power plant have been chemically analyzed for selected trace elements (As, B, F, Hg, Se, Sr, U, and V) to determine concentration vs. distance trends. Gaussian plume deposition calculations predict very little increase of trace element concentrations in soils, except for those elements highly concentrated in fly ash emissions compared to soils. Trace element soil concentrations as a function of downwind distance generally confirm these predictions, with the possible exception of Se.     

Estimation of air quality degradation due to Saharan dust at Nouakchott, Mauritania, from horizontal visibility data

It is now irrefutable that air pollution caused by large amounts of Total Suspended Particulates (TSP) and respiratory particulates or Particulate Matter less than 10 μm in aerodynamic diameter (PM₁₀) has numerous undesired consequences on human health. Air quality degradation far from the African continent, in the US and in Europe, caused by high concentrations of African dust, is seen as a major threat even though most of these countries are very distant from the Sahara. Surprisingly, no estimates of TSP or PM₁₀ levels near the Saharan dust source are available. Based on horizontal visibility observations which are reduced by the presence of dust in the atmosphere, TSP and PM₁₀ levels are estimated throughout the year 2000 at Nouakchott-Airport, Mauritania, using relations found in the literature. It appears that concentrations of particles are significant both in terms magnitude and frequency, as the 24-hour PM₁₀ thresholds established by the US EPA National Ambient Air Quality Standards and the EU Limits Values for Air Quality were exceeded 86 and 137 times, respectively. The average annual concentration is far above air quality standards and estimated at 159 μg m^?3 for TSP and 108 μg m^?3 for PM₁₀. These very high particulate levels are likely to represent an important public health hazard and should be considered as a major environmental risk.     

Trace metal contamination in and on Balsam fir (abies Balsamea (L) Mill.) Foliage in southern Quebec,Canada

Atmospheric trace metal contamination in and on forest foliage in southern Quebec has been investigated. Washed and unwashed foliage of Balsam fir from seven sampling sites with different elevation were analyzed by NAA. Metal element concentrations in needles were generally well below the suggested levels of potential phytotoxicity, except for Mn. At three rural mountain sampling locations, Mn concentration exceed 600 μg/g in washed and unwashed needles. The variability of metal concentrations between individual trees at a given site showed the expected element-specific differences, with most CV's < 50%. The variation of metal deposits on needle surfaces (ng/cm²) with elevation and sampling site depended on the element concerned. The input of Al, As, Cr, La, Sb, Sc, Sm, and V, accompanying Fe in deposits on the foliage surface, may mainly come from atmospheric deposition in the form of soil dust and air pollution. Wet deposition samples from Roundtop Mountain suggest cloud immersion as a significant trace element deposition pathway in high elevation forest.     

Trace Elements in Groundwater from Some Crystalline Rocks in the Upper Regions of Ghana

About 20 trace elements were analysed in samples from 60 boreholes located in the Upper East and West Regions of Ghana. Findings from the analysis indicated that most trace element concentrations were higher as compared to their concentrations found in natural water systems. The available chemical data of rocks in the area suggest that local bedrock is the dominant source of the trace elements found in goundwater. Aluminium, Fe, Mn, Zn, Sr, and Ba were excessively high in concentration. In comparison with WHO guidelines, all except Al, Fe, Fe and Mn values were below the recommended limits.     

Mechanisms and Factors Influencing Adsorption of Microcystin-LR on Biochars

With industrialization, great amounts of trace elements and heavy metals have been excavated and released onto the surface of the earth and dissipated into the environments. Rapid screening technology for detecting major and trace elements as well as heavy metals in variety of environmental samples has been most desired. The objectives of this study were to determine the detection limits, accuracy, repeatability, and efficiency of an X-ray fluorescence spectrometer (Niton XRF analyzer) in comparison to the traditional analytical methods, inductively coupled plasma optical emission spectrometer (ICP-OES) in screening of major and trace elements of environmental samples including estuary soils and sediments, contaminated soils, and biological samples. XRF is a fast and non-destructive method for measuring the total concentration of multi-elements simultaneously. Contrary to ICP-OES, XRF analyzer is characterized by the limited preparation required for solid samples, non-destructive analysis, increased total speed and high throughout, decreased production of hazardous waste, and low running costs as well as multi-elemental determination and portability in the fields. The current comparative study demonstrates that XRF is a good rapid, non-destructive screening method for contaminated soils, sediments, and biological samples containing high concentrations of major and trace elements. Unfortunately, XRF does not have sensitive detection limits for most trace elements as ICP-OES, but it may serve as a rapid screening tool for locating hot spots in uncontaminated field soils and sediments, such as in the US Department of Energy’s Oak Ridge site.     

Lichen biomonitoring of trace elements in a geothermal area (central Italy)

The epiphytic lichen Parmelia caperata was used systematically to biomonitor trace elements in the Travale-Radicondoli geothermal field (central Italy). The results showed a very low occurrence of potentially toxic heavy metals such as Cd, Hg and Pb, and relatively high values for As, B, Mo and elements associated with soil dust (Al, Co, Cr, Fe, Mn and Ni). Boron was the principal element of geothermal origin. Arsenic seems to originate both from power plants and adjacent thermal springs. It is concluded that trace element pollution in the area is low.     

Technogenic Magnetic Particles in Alkaline Dusts from Power and Cement Plants

During this study, we investigated the mineralogical characterization of technogenic magnetic particles (TMPs) contained in alkaline industrial dust and fly ash emitted by coal burning power plants and cement plants. The reaction of tested dust samples varied between values of pH 8 and pH 12. Their magnetic properties were characterized by measurement of magnetic susceptibility (χ), frequency dependence of magnetic susceptibility (χ_fd), and temperature dependence of magnetic susceptibility. Mineralogical and geochemical analyses included scanning electron microscopy with energy dispersive spectroscopy, microprobe analysis and X-ray diffraction. The TMPs in fly ash from hard coal combustion have the form of typical magnetic spherules with a smooth or corrugated surface as well as a skeletal morphology, composed of iron oxides (magnetite, maghemite, and magnesioferrite) that occurred in the form of incrustation on the surface of mullite, amorphous silica, or aluminosilicate particles. The TMPs observed in fly ash from lignite combustion have a similar morphological form but a different mineralogical composition. Instead of magnetite and magnesioferrite, maghemite and hematite with lower χ values were the prevailing magnetic minerals, which explains the much lower magnetic susceptibility of this kind of ash in comparison with the ash from hard coal combustion, and probably results from the lower temperature of lignite combustion. Morphology and mineralogical composition of TMPs in cement dust is more diverse. The magnetic fraction of cement dust occurs mostly in the form of angular and octahedral grains of a significantly finer granulation (<20 μm); however, spherules are also present. A very characteristic magnetic form for cement dust is calcium ferrite (CaFe₃O₅). The greatest impact on the magnetic susceptibility of cement dust results from iron-bearing additives (often waste materials from other branches of industry), which should be considered the most dangerous to the environment. Stoichiometric analysis of micro-particles confirmed the presence of heavy metals such as Pb, Mn, Cd, and Zn connected with TMPs, which are carriers of magnetic signals in atmospheric dust. Therefore, in some cases, their presence in topsoil when detected by magnetic measurement can be treated as an indicator of inorganic soil contamination.     

Exhaustive Screening of Long-Term Pollutants in Riverbank Sediments of the Wurm River,Germany

Fluvial sediments can act as archives for long-term pollution. However, in environmental studies, often only preselected contaminants and, therefore, only a limited part of the pollution are considered. Herein, geochemical investigations of riverbank samples of the Wurm River (catchment <?400 km²) depict the anthropogenic impact of the city Aachen (250,000 inhabitants) to its main outlet resulting in an exhaustive list of present pollutants including their concentrations. The study is based on 14 riverbank sediment samples at eight sampling sites on a 7.6-km-long segment of the Wurm River. The sediment samples were analyzed for grain size composition (laser diffraction particle size analyzer), total organic carbon (TOC), trace element inventory (X-ray fluorescence), and organic compounds (chromatography-mass spectrometry). Here, we report quantitative data for 71 persistent organic substances as well as six trace elements (Cu, Zn, As, Ba, Hg, and Pb) entering the Wurm River due to domestic and industrial emissions. In general, a slight decline of, e.g., PTEs, DDX, and PCB concentrations with decreasing sampling depth points to a steady improvement of conditions. Whereas no clear trends can be seen for organic pollutants along the investigated reach with increasing distance to the main source of pollution (Aachen city). As obtained concentrations for organic pollutants indicate a rather low level of pollution, trace element values exceed geogenic background values by far. Furthermore, we used selected compounds as time markers for a rough estimation of sedimentation rates. Obtained values point to a highly complex morphodynamic regime with changing sedimentation rates (0.6 to 3.0 cm a^?1) within barely 100 m of river course.     

Identification of Fine Particle Sources in Mid-Atlantic US Area

The U.S. Environmental Protection Agency (EPA) designated 20 urban areas including major cities located in mid-Atlantic US area as being in non-attainment of the new national ambient air quality standards for PM_2.5 (particulate matter ≤2.5 μm in aerodynamic diameter). To support the development of effective State Implementation Plans for PM_2.5 in the non-attainment area, 24-h integrated Speciation Trends Networks data collected in the mid-Atlantic US urban area were analyzed through the application of the positive matrix factorization (PMF). A total of 117 to 235 samples and 27 to 29 chemical species collected at the four monitoring sites between 2001 and 2003 were analyzed and six to nine sources were identified. Secondary particles provided the highest contributions to PM_2.5 mass concentrations (38–50% for secondary sulfate; 9–18% for secondary nitrate). Potential source contribution function analyses show the potential source areas and pathways of secondary particles contributing to this region, especially the regional influences of the biogenic as well as anthropogenic secondary particles. Motor vehicle emissions contributed 21–33% to the PM_2.5 mass concentration. In four sites in southern New Jersey and Delaware, gasoline vehicle and diesel emissions were tentatively separated by different abundances of organic and elemental carbons. The compositional profiles for gasoline vehicle and diesel emissions are similar across this area. In addition, other combustion sources, aged sea salt, and intercontinental dust storms were identified.     

Elemental and Base Anions Deposition in the Snow Cover of North-Eastern Estonia

Snow samples from 18 sites in Estonia were collected in February and March 1996 after 72–110 days of permanent snow cover. Three snow layers corresponding to different snow accumulation periods were separated in each sampling site. Snow water samples were analysed for sulphate (SO₄ ^2-), nitrate (NO₃ ^-), and chloride (Cl^-) ions and elemental composition. Deposition fluxes of 27 chemical species were used for factor, cluster and correlation analysis. The effects of cement dust, oil shale fly ash, sulphur dioxide and chlorine from emissions of thermal power plants were distinguished. A large number of trace metals are strongly correlated with each other (R > 0.8) and with macro-components (except NO₃ ^-), which refers to a common origin, identified as the mineral part of oil shale. Deposition fluxes of Ca, Mg, SO₄ ^2- and a number of mineral components exceed near the power plants 1–2 decimal orders the background value. The deposition fluxes in forested sites are up to 2 times higher than in open land sites. This difference may be caused by more efficient turbulent transfer over rougher surface. It is suggested, that NO₃ ^- and Zn originate mainly and Pb, Cd and Cu partially from non-local or diffuse sources (traffic, domestic heating, far transport). The results of this research could be used to evaluate the air pollution deposition models and for ecological impact estimations.     

Atmospheric deposition of trace elements in Norway: Temporal and spatial trends studied by moss analysis

The atmospheric deposition of sixteen trace elements, as inferred by their concentration in moss samples collected in 1985 from 500 sites in Norway, is compared with data from a similar survey in 1977. The deposition patterns of V, Zn, As, Se, Cd, Sb, and Pb are substantially influenced by long-range transport from other parts of Europe, but a general decline is evident from 1977 to 1985, most strongly for Pb. For Cr, Fe, Co, Ni, and Cu the deposition patterns are largely determined by contributions from point sources within Norway and on the Kola peninsula close to the Russian/ Norwegian border. The moss data for Br, I, and partly Se reflect airborne supply from the marine environment, whereas Al and Sc serve as indicators of contributions from soil dust. Contributions to the trace element concentrations in moss from sources other than atmospheric deposition are identified and discussed.     

Studying the function of ecosystem in preventing aeolian dust emission in the dryland areas of China

Aeolian dust emissions can cause many environmental hazards, like accelerating land degradation and desertification, polluting air, harming human health, and so on. The dryland areas of China (DAC) are hot spots of aeolian dust emissions. To date, many efforts have been paid to researching dust emissions processes and effects, but research studies on ecosystems' function in preventing dust emissions are still very limited. In this study, we investigated the function of DAC ecosystems in preventing dust emissions, and the corresponding driving factors through integrated wind erosion modelling system (IWEMS) modelling. The main results indicate that: (1) from 2001 to 2020, the ecosystems of DAC prevented the emission of dust ~40,554 Tg, approximately 15 times as much as the total actual dust emission (~2776 Tg); (2) the function of DAC ecosystems in preventing dust emissions was relatively strong in spring and winter; (3) grassland ecosystems had the strongest function in preventing dust emissions among all the land cover types, avoiding the emission of dust ~20,857 Tg over 2001–2020; (4) dust emission prevention function provided by the DAC ecosystems benefits almost every region of China, which provides a theoretical basis for formulating ecological compensation policies; and (5) the changes in dust emissions were dominated by wind speed in most areas of DAC.     

Quantifying Local Creation and Regional Transport Using a Hierarchical Space–Time Model of Ozone as a Function of Observed NO<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>, a Latent Space–Time VOC Process,Emissions, and Meteorology

We explore the ability of a process-based space–time model to decompose 8-hour ozone on a given day and site into parts attributable to local emissions and regional transport, to provide space–time predictions, and to assess the efficacy of past and future emission controls. We model ozone as created plus transported plus an error with seasonally varying spatial covariance parameters. Created ozone is a function of the observed NO _x concentration, the latent VOC concentration, and solar radiation surrogates. Transported ozone is a weighted average of the ozone observed at all sites on the previous day, where the weights are a function of wind speed and direction. The latent VOC process mean includes emissions, temperature, and a workday indicator, and the error has seasonally varying spatial covariance parameters. Using likelihood methods, we fit the model and obtain one set of predictions appropriate for prediction backward in time, and another appropriate for predicting under hypothetical emission scenarios. The first set of predictions has a lower root-mean-squared error (RMSE) when compared to point observations than do the 36 km gridcell averages from the Community Mesoscale Air Quality Model (CMAQ) used by the EPA; the second set has the same RMSE as CMAQ, but under-predicts high ozone values.