The adsorption potential of layered double hydroxides (LDH) of nickle–zinc–iron (NiZnFe) and its composites with single-wall carbon nanotubes (CNTs) and banana biochar (Bb) was investigated for divalent copper (Cu²⁺) removal in a batch system. Field emission scanning electron microscopy and FT-IR spectra confirmed the adsorption of Cu²⁺ onto LDH (NiZnFe) and its composites with Bb (LDH/Bb) and CNTs (LDH/cnt). The optimum equilibrium contact time was determined to be ~ 30 min, with LDH/Bb displaying the maximum uptake and removal efficiency (95%) for an initial Cu²⁺ concentration of 20 mg L⁻¹. Pseudo-second-order kinetic models presented high R² values (1.0) for all adsorbents, indicating good agreement between the theoretical adsorption capacities with experimental values. Multistep adsorption with both the surface and pore diffusion mechanism was suggested as well based on the intraparticle diffusion kinetic model. An optimum pH of 5.0 was considered with an increase in the uptake of Cu²⁺ and its removal efficiency, wherein LDH/Bb presented a greater removal efficiency and higher Cu²⁺ uptake compared with that of LDH (NiZnFe) and LDH/cnt. A gradual increase in Cu²⁺ uptake was observed in association with an increase in adsorbent dose from 0.2 to 0.5 g, with insignificant changes upon further increasing the dose of the adsorbent from 0.5 to 0.9 g. An increase in the initial Cu²⁺ concentrations from 10 to 100 mg L⁻¹ resulted in a decrease in the removal efficiency, whereas Cu²⁺ uptake increased almost linearly in the Cu²⁺ concentration range of 10–60 mg L⁻¹. Results of experimental data fitting using the Langmuir and Freundlich isotherm models suggest a dominance of monolayer adsorption, although multilayer adsorption appears to occur onto adsorbents with heterogeneous surfaces. Notably, chemisorption was also proposed to occur owing to the values of mean free energy of adsorption falling in the 8–16-kJ mol⁻¹ range, as calculated using the Dubinin–Radushkevich isotherm model. Importantly, the use of the SIP isotherm model indicated LDH/Bb to exhibit higher energy of adsorption and degree of heterogeneity than other two adsorbents. Thus, biochar or CNTs composited NiZnFe-LDH could serve as efficient adsorbents for Cu²⁺ removal from wastewater streams.

To figure out which factor contributes more on carbon emissions caused by energy consumption, this research took multisector analysis based on the Log-Mean Divisia Index Method (LMDI) and decoupling theory to assess the driving factors of carbon dioxide (CO₂) emissions in China’s six sectors from 2003 to 2016. Our empirical results reveal that China’s economy can be divided as three decoupling stages and exhibited a distinct tendency toward strong decoupling with a turning point in 2008. Thus, we discuss the impact of 2008 economic crisis on carbon emissions based on decomposition results. The empirical results of our study show the following five conclusions. (1) Most sectors in China are in weak decoupling state due to the inhibition of energy intensity on carbon emissions. (2) Different factors contribute differently to reducing emissions in different sectors, economic output has the most prominent effect, followed by energy intensity and population scale. (3) China’s current carbon emission reduction measures benefit more on energy efficiency. (4) The economic crisis has greatly reduced energy efficiency and has no significant impact on other factors. (5) If all industries adjust their energy mix, carbon emissions in China can be reduced by almost 17% every year.

Mining generates a significant quantity of waste material including ballast, gravel, and slags, which are often deposited in areas without taking into account the environment impacts and the need to ensure the physical and chemical stability of the disposed waste. One of the less studied problems is the emission of particulate matter produced by wind erosion at the dumpsites. This erosion is mainly caused by two factors, wind speed and turbulence, due to surface phenomenon. Until now, the design of waste dumpsites in the Chilean mining industry has not considered these environmental conditions. Efforts to minimize disposal costs have always been achieved by depositing ballast without considering these variables. When wind impacts this unprotected surface, it creates a source of dust that requires some special attention. The problem that this research tries to solve is to reduce particulate material to the atmosphere from waste dumps in which, under certain atmospherics and geographic conditions, specifically on winter season, its concentrations overpass the maximum limit allowed by law, generating bronchopulmonary diseases and even closing partially or totally mine operation. The result is the creation of a waste dumpsite design model, with its corresponding algorithms, which will allow optimization of the waste dumpsite design. From these results, future researches could explore more sustainable mining, such as unit operations, drilling, blasting, load and crushing material, reducing particulate material emissions to the atmosphere, and minimizing environmental impact due to exploitation.

The Kaban Lakes Integrated Assessment Model (KLIAM) was enhanced in order to assess the possible content of antibiotics in the Kaban lakes, located within the city borders of Kazan City, Tatarstan Republic in the Russian Federation, and potential for adverse environmental effects. The Kaban Lakes Integrated Assessment Model simulations suggest that the concentrations in the Nizhniy Kaban lake and Sredniy Kaban lake may exceed the predicted no effect concentration (PNEC) and low-risk limits set by EU and the WHO. Many missing data could be assumed or approximated, and simulation runs were conducted. The results are consistent with other global studies in terms of average concentrations observed elsewhere in rivers and lakes. The results suggest that the study should be followed up with lake water analysis and an assessment of antibiotic loads to the Kaban lakes. It is concluded that the results are too uncertain to initiate any policy action at the present moment and that an assessment supported by measurements would be warranted.

CO₂ emissions tend to increase more rapidly in underdeveloped economies as compared to developed countries mainly in China, India, and Asia. One of the aspects that accounts for the increasing CO₂ emissions is urbanization (UR) and it is increasing all over the world particularly in Asian and African regions. The present study examines the impact of energy use and UR on carbon emissions over the period 1995 to 2018 while using the extended STIRPAT model for Asian countries. Panel co-integration techniques and Granger causality test are applied on selected variables. FMOLS and DOLS methods are also applied to check for robustness. Findings confirm the presence of long-run co-integration among variables. The outcomes propose that energy consumption and UR have positive impact on CO₂ emissions and output. Outcomes also reveal that financial development (FD) has negative effect on emissions of CO₂ but positive effect on economic growth. Results of Granger causality technique indicate that long-run causality association exists among emissions of CO₂, economic growth, and UR. In the short run (SR), bidirectional causal relationship has been found between trade openness and FD.

Microplastics (MPs) with an average size of less than 5 mm, along with nanoplastics (NPs) of an average size of fewer than 0.1 μm are the result of huge plastic waste fragmentation or straight environmental emissions. Pollution from micro- and nanoplastics is a worldwide paradigm that raises environmental and human health concerns. They may also comprise very harmful chemicals that are implemented in plants and animals when MPs/NPs are used that may lead to higher accumulation of these compounds in food chains. In addition, higher surface area-to-volume ratio, characteristic of MPs/NPs can contribute to their potentially harmful impact as other pollutants, like continuous organic contaminants, can also be bio-accumulated and adsorbed. A complex issue correlated with MPs/NPs is their ability to absorb and interact with other common pollutants in the environment, such as metals, pharmaceuticals, and other contaminants. Thus, MPs/NPs can directly influence on destiny and toxicity of these substances to the environment and organisms. In this review, first, we introduce possible sources and formation, their destinies, and environmental impact of MPs/NPs and then explain feasible paths of all these particles entering the human body. Then, the review highlights the effect of MPs/NPs on human health. Finally, it provides a brief summary of the potential as well as the neurological toxicity of MPs/NPs.

The rapid pace of economic growth and urbanization in China affects both large and small cities of the country, causing an increase of pollutant concentrations in the air. The South Gobi is one of the main deserts and semidesert regions of the country; therefore, the study of air pollution near the potential source of natural aerosols is of great importance. Data obtained in the period from 1 January 2016 to 31 December 2019 was used to analyze spatial-temporal characteristics of atmospheric pollutants (PM₂.₅, PM₁₀, SO₂, NO₂, and CO) in eight cities. Total mean concentrations of PM₂.₅ and PM₁₀ were 36.1 ± 21.1 μg/m³ and 98.6 ± 108.7 μg/m³. The occurrence rates of concentrations exceeding the Chinese National Ambient Air Quality Standard (CNAAQS) grade 1 and grade 2 were 40.1% and 5.4% for PM₂.₅ and 82.9% and 11.64% for PM₁₀ in the region. Total concentrations of SO₂, NO₂, and CO did not exceed the CNAAQS standard and were 20.8 ± 23.6 μg/m³, 22.6 ± 11.9 μg/m³, and 0.72 ± 0.39 mg/m³, respectively. The PM₂.₅ to PM₁₀ ratio increased from 0.35 in spring to 0.46 in winter suggesting the predominance of coarse aerosol fractions in the atmosphere. Based on data on aerosol optical depth (AOD) and Ångström exponent (AE) ratio obtained from Moderate Resolution Imaging Spectroradiometer (MODIS), the predominant aerosol types in the region are Clean Сontinental and Mixed. Maximum concentrations of pollutants and the highest AOD values in the region air are observed in spring and winter. Results set forth in this article will be an important basis for further regional studies on air quality and distribution of sources.

Multivariate dispersion has proven to be a broad β-diversity measure that shows the heterogeneity of environmental conditions. The dispersion patterns of pelagic ciliate communities were investigated at eight water depths in the northern Bering Sea of the western Arctic Ocean and Chukchi Sea. Multivariate analysis indicated that (1) pelagic ciliates showed significant variability in multivariate dispersion on a vertical scale, (2) dispersion patterns were shaped by both the species composition and individual abundance, (3) vertical variation in species occurrence was significantly related to nutrients and chlorophyll a, and (4) the dispersion measures at both species occurrence and species abundance resolutions were significantly negatively related to salinity and dissolved oxygen. This suggests that multivariate dispersion measures driven by both species composition and the individual abundance of pelagic ciliates may be a useful indicator of environmental heterogeneity in marine ecosystems.

The collapse of the Fundão dam in Mariana, MG, in 2015 resulted in the overflow of more than 50 million m³ of mud containing mine tailings, leaving a path of destruction and immeasurable social and environmental consequences. Tailings’ chemical and physical assessments revealed the presence of some elements at levels higher than those allowed by Brazilian guidelines. The tailings also showed high density, which restricts vegetation recovery. Therefore, this study aimed to analyze the effects of mud containing mine tailings from the Fundão dam on the germination and initial growth and development of three plant species: millet, maize, and sorghum. These species were cultivated on substrates with five tailings proportions: 0 T (100% sand), 25 T (25% tailings + 75% sand); 50 T (50% tailings + 50% sand); 75 T (75% tailings + 25% sand); and 100 T (100% tailings). In experiment I, the germination and initial growth of seedlings (plants with 1 or none fully expanded leaf) in these substrates were evaluated. In experiment II, growth parameters, photosynthetic efficiency (gas exchange and chlorophyll a fluorescence), metal accumulation, and plant root morphology of the same species were evaluated at the three fully expanded leaves vegetative stage (V3). Overall, the germination of seedlings and the initial growth of the three species analyzed were not affected by the presence of tailings. However, in plants at the V3 stage, morphophysiology variations differed among species, given that their growth, biomass accumulation, and root dynamics were altered. Proportions of tailings in the substrate did not influence the absorption of iron or manganese by the studied plants. At the V3 stage, maize was the most tolerant, with a more robust root system, and showed fewer morphological changes and greater water use efficiency than the other studied species.

How mercury flows from geological sources to society and to the environment was modelled for this study. The industrial dynamics of mercury was modelled and included in the integrated assessment model WORLD7. The simulated mercury losses were used as input for a simplified global model for environmental pollution. The outputs were analysed and used to assess mercury pollution amounts and supply to society. In fossil fuels, there are a potential stock of 2 million tons in coal and other hydrocarbons, and 450,000 tons of that could be released to the environment if the fossil fuels are all to be burned. Such release would potentially cause major environmental damage and a significant human health risk. The simulations suggest that environmental mercury flows may peak in 2025, and slowly decline as mercury gets immobilized in nature. The simulations show that the pollution from technical use is eliminated by putting the 2013 Minimata Convention into effect, but that environmental pollution from fossil fuels combustion and from environmental re-emissions will remain a significant problem for the next decades.