Air pollution is one of the major global hazards and industries have been one of its major contributors. This paper primarily focuses on analyzing the dispersion characteristics of buoyant plumes of the pollutant released from a multi-flue vertical stack into a variable temperature gradient atmosphere (α) in a constant-velocity cross wind using two stack configurations—inline and parallel. The study is conducted for different Froude numbers, Fr = 12.64, 9.55, and 8.27. The atmospheric temperature gradients considered for the study are 0, +1, +1.5, and +2 K/100 m. The numerical study is done using the commercial computational fluid dynamics (CFD) code FLUENT. The effects of stack configuration, α, and Fr on the plume characteristics are presented. It is observed that the plume rises higher and disperses over a larger area with the inline configuration due to better mixing and shielding effect. With higher α, it is seen that the plume rises initially and then descends due to variation of the buoyant force. The plume rise initially is strongly influenced by the momentum of the jet, and as it moves downstream, it is influenced by the cooling rate of the plume. Furthermore, the plume rises higher and disperses over a larger area with a decrease in Fr.

Chemical and sulfate-sulfur isotopic compositions of water-soluble inorganic ions were analyzed for aerosol sample particulate matter with aerodynamic diameter ≤10 μm (PM₁₀) collected during 17–28 December 2012 at Yichang City, Hubei Province, central China. Most water-soluble inorganic ions, except for NO₃ ⁻ and NH₄ ⁺, showed slightly higher concentration in daytime than in nighttime, and the major detected ions followed the order of SO₄ ²⁻ > NO₃ ⁻ > Ca²⁺ > Na⁺ > NH₄ ⁺ > Cl⁻ in daytime and nighttime, of which SO₄ ²⁻ is the most abundant ionic component that accounted for about 49.1 and 49.3 % of the total mass of analyzed ions in daytime and nighttime, respectively. According to the correlation coefficients among the mass concentrations of water-soluble inorganic ions, there may mainly exist in forms of (NH₄)₂SO₄ and NH₄NO₃ in daytime and NH₄NO₃ in nighttime. The δ³⁴S values of sulfate ranged from +2.82 to +4.63 ‰ (average +3.97 ‰) in daytime and from +2.90 to +5.39 ‰ (average +4.08 ‰) in nighttime, indicating that the source of sulfate in PM₁₀ was mainly derived from coal burning (δ³⁴S, +3.68 ‰) in Yichang City. The [NO₃ ⁻]/[SO₄ ²⁻] mass ratio varied between 0.2 and 0.6 with an average of 0.4 in daytime and 0.1 to 0.8 with an average of 0.4 in nighttime, which implying that the stationary source emissions would be more important than the vehicle emissions in the studied area. As a whole, the mixture of coal burning, vehicle exhaust, and resuspended road dust would be responsible for the sources of PM₁₀ in Yichang City during wintertime.

Pot experiments were conducted to evaluate the effects of gibberellic acid (GA₃) and ethylenediaminetetraacetic acid (EDTA) on growth parameters, cadmium (Cd) phytoextraction, total phenolics, free proline and chlorophyll content of Parthenium hysterophorus plant grown in Cd-contaminated (100 mg/kg) soil. GA₃ was applied as foliar spray (10⁻², 10⁻⁴ and 10⁻⁶ M) while EDTA (40 mg/kg soil) was added to soil as single and in split doses. Results showed decrease in growth parameters due to Cd stress but P. hysterophorus plant demonstrated Cd hyperaccumulator potential based on bioconcentration factor (BCF). Lower concentration of GA₃ (10⁻⁶ M) showed highest significant increase in the growth parameters while Cd concentration, accumulation (1.97 ± 0.11 mg/DBM) and bioconcentration (9.75 ± 0.34) was significantly higher in the treatment T11 (GA₃ 10⁻² + split doses of EDTA). Cadmium significantly increased the root free proline while total phenolic concentration was significantly high in all parts of the plant. Chlorophyll contents were significantly reduced by Cd. GA₃ showed significant increase in phenolic and chlorophyll contents in plant. Cadmium accumulation in plant tissues showed positive correlation with free proline (R ² = 0.527, R ² = 0.630) and total phenolics (R ² = 0.554, R ² = 0.723) in roots and leaves, respectively. Cd contents negatively correlated with biomass, chlorophyll and total water contents. Proline and phenolic contents showed positive correlation with dry biomass of plant. These findings suggest further investigation to study the role of endogenous phenolics and proline in heavy metal phytoremediation.

Andra Environmental Specimen Bank (ESB) was established in 2010 as a part of the Perennial Observatory of the Environment (OPE), ongoing Long-Term Environmental Research Monitoring and Testing System located next to the Underground Research Laboratory (URL) at Bure, Meuse/Haute-Marne, France. The URL is used to study the deep geological disposal of high and intermediate level radioactive waste. Andra ESB is designed to archive during at least 100 years samples collected to define the initial state of environmental quality of the local area before the construction of industrial facilities and to ensure the traceability of long-term series of samples collected by the OPE (http://www.andra.fr/ope), using safe long-term conservation practices. Samples archived in the bank include some local food chain products (milk, cheese, honey, cereals, grass, cherry plum…) and specimen usually archived internationally to monitor the environmental quality (soil, sediment, water, fish, tree leaves, wild life, etc.). Regarding the different samples and analytical issues, three conservation modalities and facilities were designed: dry conservation under controlled temperature and humidity, cryopreservation in liquid nitrogen (LN2) vapor phase freezers (−150 °C) and in deep-freezing at −80 °C for temporary storage and raw samples before preparation. Andra ESB is equipped with a sample preparation clean room, certified ISO Class 5, dedicated to cryopreservation. This paper describes this first French experiment of long-term chemical quality monitoring and samples cryopreservation of different ecosystems and environmental compartments.

In this work, kriging with covariates is used to model and map the spatial distribution of salinity measurements gathered by an autonomous underwater vehicle in a sea outfall monitoring campaign aiming to distinguish the effluent plume from the receiving waters and characterize its spatial variability in the vicinity of the discharge. Four different geostatistical linear models for salinity were assumed, where the distance to diffuser, the west-east positioning, and the south-north positioning were used as covariates. Sample variograms were fitted by the Matèrn models using weighted least squares and maximum likelihood estimation methods as a way to detect eventual discrepancies. Typically, the maximum likelihood method estimated very low ranges which have limited the kriging process. So, at least for these data sets, weighted least squares showed to be the most appropriate estimation method for variogram fitting. The kriged maps show clearly the spatial variation of salinity, and it is possible to identify the effluent plume in the area studied. The results obtained show some guidelines for sewage monitoring if a geostatistical analysis of the data is in mind. It is important to treat properly the existence of anomalous values and to adopt a sampling strategy that includes transects parallel and perpendicular to the effluent dispersion.

In the present research, the potential of two biochars produced by the thermal decomposition of wheat straw (BCS) and wicker (BCW) for Cr(VI) ions removing from wastewater was investigated. The pH and the presence of chlorides and nitrates were also investigated. The Freundlich and Langmuir models were applied for the characterization of adsorption isotherms. The Langmuir model has better fitting of adsorption isotherms than the Freundlich model. The sorption process can be described by the pseudo second-order equation. The optimal adsorption capacities were obtained at pH 2 and were 24.6 and 23.6 mg/g for BCS and BCW, respectively. X-ray photoelectron spectroscopy (XPS) studies confirmed that Cr(III) ions were the most abundant chromium species on the biochars’ surface. The results indicated that the sorption mechanism of Cr(VI) on biochar involves anionic and cationic adsorption combined with Cr(VI) species reduction.

Cadmium (Cd) toxicity is a widespread problem in crops grown on contaminated soils, and little information is available on the role of inorganic amendments in Cd immobilization, uptake, and tolerance in crops especially under filed conditions. The effect of three amendments, monoammonium phosphate (MAP), gypsum, and elemental sulfur (S), on Cd immobilization in soil and uptake in wheat and rice plants, under rotation, were investigated under field conditions receiving raw city effluent since >20 years and contaminated with Cd. Three levels of each treatment, 0.2, 0.4, and 0.8 % by weight, were applied at the start of the experiment, and wheat was sown in the field. After wheat harvesting, rice was sown in the same field without application of amendments. Both crops were harvested at physiological maturity, and data regarding grain yield, straw biomass, Cd concentrations, and uptake in grain and straw, and bioavailable Cd in soil and soil pH were recorded. Both MAP and gypsum application increased grain yield and biomass of wheat and rice, while S application did not increase the yield of both crops. MAP and gypsum amendments decreased gain and straw Cd concentrations and uptake in both crops, while S application increased Cd concentrations in these parts which were correlated with soil bioavailable Cd. We conclude that MAP and gypsum amendments could be used to decrease Cd uptake by plants receiving raw city effluents, and gypsum might be a better amendment for in situ immobilization of Cd due to its low cost and frequent availability.

This paper is a contribution for validating a standard method for trace element monitoring based on transplants and analysis of aquatic bryophytes, in the framework of the EC Directive 2000/60. It presents the results of an experiment carried out to assess significant differences in the amount and variability of As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in three moss species (Cinclidotus aquaticus, Fontinalis antipyretica, Platyhypnidium riparioides) and two different parts of the moss (whole plant vs apical tips). Mosses were caged in bags made of a plastic net and transplanted for 2 weeks to an irrigation canal impacted by a waste water treatment plant. Trace element concentrations were measured by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) before and after exposure to the experimental and control sites in five samples. Enrichment factors >>2 were found for Cu, Ni, Mn, Pb and Zn in all moss species, lower in C. aquaticus, intermediate in F. antipyretica and higher in P. riparioides (the species we recommend to use). The analysis of apical tips after exposure instead of the whole plant led to (I) lower concentrations of As, Co, Cr, Fe and Zn in C. aquaticus (−7 to −30 %) and of Fe and Pb (−13, −18 %) in P. riparioides, (II) higher concentrations of Cu, Ni and Zn (+14 to +18 %) in P. riparioides, while (III) no significant difference (p > 0.05) in F. antipyretica. Data variability after exposure was generally lower in apical tips, especially in C. aquaticus and in F. antipyretica, less in P. riparioides. In the aim of standardizing the moss-bag technique, the analysis of apical tips is recommended.

Rare earth elements (REE) have been recognised as critical raw materials, crucial for many clean technologies. As the gap between their global demand and supply increases, the search for their alternative resources becomes more and more important, especially for the countries which depend highly on their import. Coal fly ash (CFA), which when not utilised is considered waste, has been regarded as the possible source of many elements, including REE. Due to the increase in the energy demand, CFA production is expected to grow, making research into the use of this material a necessity. As Poland is the second biggest coal consumer in the European Union, the authors have studied different coal fly ashes from ten Polish power plants for their rare earth element content. All the fly ashes have a broadly similar distribution of rear earth elements, with light REE being dominant. Most of the samples have REE content relatively high and according to Seredin and Dai (Int J Coal Geol 94: 67–93, 2012) classification can be considered promising REE raw materials.

This study investigates the influence of Internet retailing on carbon dioxide (CO₂) emission in 77 countries categorized into developed and developing countries during the period of 2000–2013. To realize the aims of the study, a model that represents pollution is established utilizing the panel two-stage least square (TSLS) and the generalized method of moments (GMM). The results for both regressions similarly indicated that GDP growth, electricity consumption, urbanization, and trade openness are the main factors that increase CO₂ emission in the investigated countries. Although the results show that Internet retailing reduces CO₂ emission in general, a disaggregation occurs between developed and developing countries whereby Internet retailing has a significant negative effect on CO₂ emission in the developed countries while it has no significant impact on CO₂ emission in the developing countries. From the outcome of this study, a number of policy implications are provided for the investigated countries.