Cadmium (Cd) stress is a serious concern in agricultural soils worldwide, and increasing accumulation and subsequent transfer to humans via the food chain can have potentially harmful effects. In this study, field experiments were conducted to examine the uptake and translocation of Cd in rice, changes in the soil Cd speciation, and the subsequent effect on Cd accumulation in rice under combined organic (farmyard manure and crop straw) and inorganic (sepiolite, lime, and calcium-magnesium phosphate) soil amendments. The results showed that farmyard manure combined with sepiolite or lime and straw combined with lime or calcium-magnesium phosphate reduced the Cd translocation from the rice roots to the straw and the grains, significantly decreasing the Cd accumulation in brown rice. In addition, straw combined with sepiolite, lime, or calcium-magnesium phosphate reduced the Cd accumulation in brown rice but increased the Cd translocation from the roots to the straw by 37.8–279.3% compared with the control. Organic-inorganic amendments also decreased the soil exchangeable Cd and increased the organic-bound Cd by more than 40%. Fe-Mn oxide-bound Cd also increased but varied with growth. Cd accumulation in brown rice showed a significant positive relationship with soil exchangeable Cd at 90 days after transplantation, while at 30 days, the increase in Fe-Mn oxide- and organic-bound Cd was found to be the key factor in reducing the Cd accumulation in rice. These findings suggest that straw (under rice-rape rotation) and farmyard manure (under rice-wheat rotation) combined with sepiolite or lime are widely applicable as agronomic control techniques aimed at lowering Cd pollution.

The degradation of roxithromycin (ROX) by hydroxyl radical (·OH) generated by UV/H₂O₂ was systematically investigated in terms of degradation kinetics, effects of water chemistry parameters, oxidation products, as well as toxicity evaluation. The degradation of ROX by UV/H₂O₂ with varying light irradiation intensity, initial ROX concentration, and H₂O₂ concentration in pure water and wastewater all followed pseudo-first-order kinetics. The second-order rate constant for reaction between ROX and ·OH is 5.68 ± 0.34 × 10⁹/M/s. The degradation rate of ROX increased with the pH; for instance, the apparent degradation rates were 0.0162 and 0.0309/min for pH 4 and pH 9, respectively. The presence of natural organic matter (NOM) at its concentrations up to 10 mg C/L did not significantly affect the removal of ROX. NO₃⁻ and NO₂⁻ anions inhibited the degradation of ROX due to the consumption of ·OH in reactions with these ions. Fe³⁺, Cu²⁺, and Mg²⁺ cations inhibited the degradation of ROX, probably because of the formation of ROX-metal chelates. A total of ten degradation products were tentatively identified by HPLC/LTQ-Orbitrap XL MS, which mainly derived from the attack on the oxygen linking the lactone ring and the cladinose moiety, tertiary amine and oxime side chain moiety by ·OH. The toxicity evaluation revealed that UV/H₂O₂ treatment of ROX induced the toxicity to bioluminescent bacteria increased.

The present work is dedicated to the experimental analysis on the influence of fuel-borne additives on ternary fuel blend operated in a single cylinder DI diesel engine. Alumina (Al₂O₃) nanoparticles were chosen as fuel additives at dosing levels of 10, 20, and 30 ppm, respectively, and the ternary fuel (TF) is prepared by blending 70% diesel, 20% Jatropha biodiesel, and 10% ethanol. Performance characteristics like brake thermal efficiency (BTE) and brake-specific energy consumption (BSEC) and emission characteristics like HC, CO, NOx, and smoke along with combustion characteristics like cylinder pressure, HRR (heat release rate), and CHRR (cumulative heat release rate) were considered for analysis. Based on experimentation, it is observed that TF blended with 20 ppm alumina nanoadditive (TF20) resulted in higher BTE and lowered BSEC by 7.8 and 4.93% and lowered HC, CO, NOx, and smoke emissions by 5.69, 11.24, 9.39, and 6.48% in comparison with TF. Moreover, TF20 resulted in higher cylinder pressure, HRR, and CHRR of about 72.67 bar, 76.22 J/°CA, and 1171.1 J, respectively, which are higher than those of diesel and TF. Hence, it is concluded that the addition of 20 ppm alumina nanoadditive in TF can enhance the engine performance and combustion as well as lower the exhaust pollutants simultaneously.

Schizophyllum commune is a filamentous basidiomycete which can degrade complex organic macromolecules like lignin by the secretion of a large repertoire of enzymes. One of these white rot enzymes, laccase, exhibits a broad substrate specificity and is able to oxidize a variety of substances including carbonaceous rocks. To investigate the role of laccase in bioweathering, laccase gene lcc2 was overexpressed, and the influence on weathering of black slate, originating from a former alum mine in Schmiedefeld, Germany, was examined. The metal release from the rock material was enhanced, associated with a partial metal accumulation into the mycelium. A sequestration of metals could be shown with fluorescent staining methods, and an accumulation of Zn, Cd, and Pb was visualized in different cell organelles. Additionally, we could show an increased metal resistance of the laccase overexpressing strain.

Agroforestry practices aim to achieve environmentally friendly land use. Fungi play a primarily role in soil organic carbon and nutrient maintenance, while the response of the soil fungi community to land use changes is little explored. Here, a high-throughput sequencing method was applied to understand the fungal community structure distinction in ginkgo agroforestry systems and adjacent croplands and nurseries. Our results showed that the agroforestry systems achieved better soil fertility and carbon contents. The agroforestry practices significantly altered the composition of soil fungal communities comparing with pure gingko plantation, adjacent cropland, and nursery. The dominant fungal phyla were always Ascomycota and Basidiomycota. The relative abundance of Ascomycota was correlated with the TN and AP, while the abundance of Basidiomycota was negatively correlated with the TN and NN. The soil organic carbon, total nitrogen, and nitrate nitrogen explained 59.80% and 63.36% of the total variance in the fungal community composition in the topsoil and subsoil, and the available phosphorus also played a key role in the topsoil. Considering soil fertility maintenance and fungal community survival and stability, the agroforestry systems achieved better results, and the ginkgo and wheat system was the best among the five planting systems we studied. In the ginkgo and wheat system, applying readily available mineral nitrogen fertilizer either alone or in combination with organic amendments will improve the soil quality and fertility.

Waste electrical and electronic equipment (WEEE) contains both toxic and valuable materials. Due to rapid development of information and communication technologies (ICT), a large amount of WEEE have been produced, leading to increasing academic efforts in this field. This study aims to depict the trends and features of WEEE-related studies through a bibliometric analysis. The results show that the total number of WEEE-related publications had sharply increased, with China as the leading country. University of Chinese Academy of Sciences is the most productive WEEE-related research institution, while Mai BX is the most productive author. As such, Waste Management, Journal of Cleaner Production, and Environmental Science & Technology are the most influential journals. The research hotspots of WEEE mainly focus on the recycling and treatment technologies, environmental impacts, and relevant policies of WEEE. By tracing the evolutionary pathway of WEEE research, it is clear that the research frontiers have switched from electronic equipment, extended producer responsibility, sediment, environment and design, risk assessment to life cycle assessment, mobile phone, and behaviors. This study provides valuable insights to those WEEE-related scholars so that they can identify their own research topics and partners. This paper is one of the first studies in WEEE research field that offers critical discussions and suggestions related to research development and future trends, and used visualized tools to present the holistic picture of this field.

A hybrid polymer for deep removal of arsenic from aqueous solutions was obtained by loading of waste Fe/Mn oxides into a chitosan matrix. The process was optimized by studying the influence of selected individual factors and their reciprocal combinations on the adsorptive and physical properties of the product. The influence of chitosan solution concentration, inorganic load amount, the ratio of Fe/Mn oxides to chitosan, and polymer cross-linking degree on kinetics of As(III) and As(V) adsorption was examined. The optimal values of the parameters were chitosan polymer concentration 1.5% w/w, inorganic load to chitosan ratio 1.67, and glutaraldehyde to chitosan amine groups molar ratio 3:1. The selected products were evaluated in terms of their morphology (scanning electron microscopy (SEM) with EDS analysis), porosity (N₂ and CO₂ adsorption isotherms), surface properties (Fourier-transform infrared spectroscopy (FTIR), isoelectric point determination) and durability in an acidic environment. The proposed process makes it possible to obtain a product combining beneficial adsorptive properties toward arsenic with the physical form and durability essential in fixed-bed adsorption systems.

Various studies have illustrated that exposure to ambient air pollution has negative impacts on health. However, little evidence exists on the effects of ambient air pollution on circulatory mortality in Xi’an, China. This study aims to investigate and ascertain the association between short-term exposure to ambient air pollutants and circulatory mortality in Xi’an, China. Daily average concentrations of PM₂.₅, SO₂, and O₃, meteorological data (temperature and relative humidity) and daily counts of circulatory mortality were obtained between January 2014 and June 2016. Mortality was stratified by gender and age group (≤ 64 years and ≥ 65 years). A generalized additive model (GAM) with natural splines (NS) was constructed to analyze the relationship between ambient air pollutants and daily circulatory mortality. There were 57,570 cases of circulatory mortality, with cerebrovascular and ischemic heart diseases accounting for 48.5% and 43.5%, respectively. All ambient air pollutants displayed different seasonal patterns. In the single pollutant model, 10 μg/m³ increase in 2-day moving average concentrations of PM₂.₅, SO₂, and O₃ was associated with relative risk of 1.288(1.198, 1.388), 1.360(0.877, 2.331), and 1.324(1.059, 1.705) in circulatory mortality, respectively. After adjusting for collinearity in the multi-pollutant model, the effects remained statistically significant. The ≥ 65 years and female sub-groups were associated with a higher risk of circulatory mortality. Short-term exposure to ambient air pollutants plays a pivotal role in the genesis of circulatory mortality in Xi’an. Responses to ambient air pollutants exposure in relation to circulatory mortality are different when analyzed by sub-groups.

The aim of our study was to investigate the concentrations of toxic metals in the feathers of predatory birds in the Hortobágyi Madárpark (Bird Hospital Foundation). Samples were collected from different predatory birds originated from the eastern and north-eastern region of Hungary. Inductively coupled plasma optical emission spectrometry was used to determine the concentration of toxic metals. The mean values varied between bird species groups, their concentrations were between 0.29 ± 0.24 and 0.40 ± 0.30 mg/kg for arsenic (As), 0.09 ± 0.03 and 0.20 ± 0.18 mg/kg for cadmium (Cd), 1.15 ± 1.40 to 2.30 ± 1.52 mg/kg for lead (Pb) and 0.58 ± 0.31 to 2.19 ± 1.25 mg/kg for mercury (Hg), respectively. The measured values are not over the considered threshold values for these toxic metals and in accordance with similar concentrations of them recorded in similar species within Europe. No significant differences were found in their concentration between genders or age in the species. According to the detected concentrations of these metals, their levels accumulated in the feather of the investigated birds do not indicate the possibility of poisoning.

External morphology and internal carbonaceous compositions are important characteristics for the source recognition of atmospheric particulate matter (PM). The fractal dimension of morphology and carbon components of diesel PM with different sizes both at high and low load were studied through fractal theory and thermal optical reflection method. It is revealed that small-size PM absorbs more soluble organic fractions and correspondingly has greater box dimension. Due to heavy aggregation, PM collected at low load has greater box dimension than that at high load because of heavy aggregation. OC1, which is the most volatile among organic carbons, is remarkably increased at low load or for small-size PM, absorbing more unburned hydrocarbons. At low load, a large amount of EC1 (char-EC) is generated and the ratio of OC/EC is more than 10, while, at high load, the EC is mainly composed of EC2 (soot-EC) and the ratio of OC/EC is less than 1. Apparently, the box dimension from the morphology of diesel PM presents a positive correlation with the ratio of OC/EC. Via above external and internal characteristics, particulates exhausted from motor vehicles in the atmosphere can be beneficially identified.