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The review also outlines Hg build-up in edible plant tissues and associated health risks. The biogeochemical role of Hg in the soil-plant system and associated health risks have been described with well summarized and up-to-date data in 12 tables and 4 figures. We believe that this comprehensive review article and meta-analysis of Hg data can be greatly valuable for scientists, researchers, policymakers and graduate-level students. This study evaluates the effects of land use and soil management on a combination of physico-chemical, biological and hydrological properties of soil, in order to assess its quality. Three land uses were selected at the Fuman area, near Masouleh (Iran), grouping soils covered by tea, garden crops and rice. A total of 24 soil samples (3 land uses × 4 replications × 2 soil layers, topsoil and sub-surface soil) was collected; microbial respiration, available water, stability of soil aggregates, pH, organic matter, cation exchange capacity and nutrient content (P, K, N, Mg and Ca) were determined in each land use/soil layer. In comparison with other land uses, garden showed the highest available water, aggregate stability, microbial respiration, nutrient contents and cation exchange capacity, whereas the latter three soil properties had the lowest values in soils covered by tea and rice crops. Based on these results, under the experimental conditions garden had the highest soil quality among the investigated land uses. Conversely, much caution must be paid to some soil properties of tea and rice crops, such as cation exchange capacity, microbial respiration and nutrient contents, which are the lowest among the investigated land uses. Moreover, the differences in the analysed soil properties between the two soil sampling depths were statistically significant (p  less then  0.05). Finally, a Principal Component Analysis clearly clustered soils covered by garden, tea and rice crops in three differentiated groups according to the sampled soil properties. This study provides a contribution in understanding the variability of soil properties under different land uses, indicating that some of these properties must be considered with caution, in order to avoid a decay of soil health. In this study, it was assessed the effectiveness to correct for inner filter effect (IFE) the fluorescence spectra of several wastewaters (i.e., primary, secondary and tertiary wastewater effluents) and wastewater-impacted surface waters using a common method based on UV absorbance measurements. In samples of secondary/tertiary wastewater effluents and surface waters, IFE was severe at excitation wavelengths 240 nm. Overall, the QE increased with the increase of nitrite/nitrate concentration in wastewater. Total suspended solids (TSS) (i.e., particulate organic matter) in water produced intense fluorescence peaks in the tyrosine-like and tryptophan-like region of EEM, and TSS increased the absorbance values at all the excitation wavelengths of the UV-visible absorption spectra in unfiltered samples compared to 0.7 μm filtered samples. On the contrary, tertiary effluents employing full scale sand filtration (TSS  less then  2-4 mg/l) had similar UV absorbance and fluorescence spectra to 0.7 μm filtered samples. Finally, it was observed that uncorrected fluorescence intensities in the humic-like region of EEM were similar in both filtered and unfiltered samples, and it was independent of TSS concentration, dilution factor and water quality. The present study describes the preparation of 50.3 nm superparamagnetic nanosorbents with high surface area for the adsorptive removal of lead and methyl orange from water. This material is based on the surface modification of iron oxide superparamagnetic nanoparticles with a double-shell coating of mesoporous silica whose porosity was increased up to 570 m2/g by the addition of a porogenic material and its calcination. The adsorptive performance of the nanosorbent was evaluated as a function of several parameters (e.g. solution pH, pollutant initial concentration, and contact time), concluding that pHs around 5 are needed to avoid precipitation of Pb2+ as Pb(OH)2 and the equilibrium adsorption capacity is reached after 2 h in all cases. The experimental data on the adsorption capacity of lead and methyl orange onto the nanosorbent were fit to a pseudo-second order kinetic model and Langmuir isotherm model. The maximum adsorption capacity value increases from 35 up to 50 mg/gNS for lead removal with increasing nanosorbent surface area. Contrary, for methyl orange the maximum adsorption goes up to 240 mg/gNS, indicating a larger nanosorbent surface affinity for the organic matter that is able to diffuse through the silica pores as probed by the intraparticle diffusion model. In addition, we found an good reusability (100% recovering after 4 sorption/desorption cycles for methyl orange removal), which makes of this magnetic nanosorbent suitable for remediation technologies. Highly efficient visible-light-responsive Z-Scheme CuBi2O4/Ag3PO4 photocatalysts were prepared by a hydrothermal synthesis and in-situ deposition method and characterized comprehensively. Under visible-light irradiation, the photocatalytic performance of CuBi2O4/Ag3PO4 in the degradation of diclofenac sodium (DS) in aqueous solutions was studied under different conditions such as different catalyst composition, solution pH, and concentration of S2O82- or H2O2, and the response surface methodology (RSM) was used to analyze the interaction effect of the parameters. The optimal activity of CuBi2O4/Ag3PO4 was achieved at the mass ratio of 37 and pH of 4.42. Moreover, the introduced S2O82- could significantly enhance the catalytic activity of CuBi2O4/Ag3PO4; when 1 mM S2O82- was added to the catalytic system, 10 mg/L of DS could be completely degraded within 60 min, but the structure of CuBi2O4/Ag3PO4 was severely destroyed. While when H2O2 was introduced into the system, both the activity and stability of CuBi2O4/Ag3PO4 were improved significantly. Finally, the photodegradation pathway of DS is proposed and the photocatalytic mechanism of CuBi2O4/Ag3PO4 under different conditions is explained. CuBi2O4/Ag3PO4 and CuBi2O4/Ag3PO4 (S2O82-) photocatalytic systems follow the Z-Scheme theory, and Ag0 formed on the surface of catalyst serves as the recombination center for the photogenerated e- from the conduction band (CB) of Ag3PO4 and h+ from the valence band (VB) of CuBi2O4; meanwhile, the catalytic degradation of DS by CuBi2O4/Ag3PO4 in the presence of H2O2 follows the heterojunction energy band theory. Agricultural straw burning is prevalent globally with a long history, but evidence on its pollution and health impact is limited in many countries. This study quantifies the effect of agricultural straw burning on urban air quality in China. Fixed-effects (FE) panel regression models are employed to link straw burning points detected by high-resolution satellites to air quality monitored at 1650 ground-level stations from 2013 to 2015. The method can explain over 80% of the monthly variation in urban air quality during straw burning seasons. The results show that straw burning primarily affects particulate matter, and has negligible effects on other pollutants. Specifically, ten additional burning points in a month in the rural farmland of a city can lead to a 5.19 ± 2.54 µg/m3 (3.67%±1.76%) increase in urban PM10 concentration. The effect is statistically significant for monthly burnings over 20 points. Upwind burnings' effect is 2-4 times larger than that of non-upwind burnings. The contribution from straw burning remains significant for daily and annual PM10 in urban areas. These estimates imply that straw burning should be properly regulated to improve air quality and protect public health in China, and the method and findings have broad implications for other agrarian regions with similar issues. Coral tissue thickness (CTT) is an effective indicator of the adaptability of corals to environmental stress, but the relationships between the spatial and intergeneric variation of coral tissue across latitudes and tolerance to environmental stress are not well understood. To investigate this, the CTT of 768 specimens of 10 typical coral genera and surrounding seawater parameters were measured in six coral reef regions (CRRs) across the 9-22°N latitudes in the South China Sea (SCS). Results showed significant differences in CTT between different genera of corals and CRRs. CTTs were significantly higher in the northern SCS than in the southern SCS. There was also notable intergeneric variation, with the abundance of branching Acropora and foliaceous Pavona being significantly lower than that of massive Porites, Galaxea, Favia, Favites, Hydnophora, Platygyra, and encrusting Montipora, Psammocora across these CRRs. Redundancy analysis showed that dissolved inorganic nitrogen (DIN), soluble reactive phosphorus (SRP), sea surface temperature (SST), turbidity, and transparency were the main factors affecting CTT. Overall CTT, irrespective of genus, was significantly positively correlated with DIN, SRP, and latitude, but was significantly negatively correlated with transparency and SST. Further analysis suggested that corals in the southern SCS are mainly threatened by thermal stress, whereas in the northern SCS, corals have often suffered from destructive anthropogenic disturbance. Although seawater conditions were normal during on-site investigation, a large number of branching corals (e.g., Acropora corals) have been lost in the last several decades due to destructive human activity. In contrast, massive and encrusting corals may have higher energy reserves and photo-protective capacities due to their thicker tissues, and consequently have higher tolerance to environmental stress. Therefore, the coral communities of the SCS have gradually been transformed from branching corals to massive/encrusting corals. Antimony (Sb) is a toxic element for both human and plants, but the toxic responses of plants to different forms of antimony and the associated mechanisms are unknown. read more This study was carried out to investigate the effects of different forms of Sb [Sb(III) and Sb(V)] on the root exudates, root endogenous hormones, root cell wall components and antioxidant systems in rice plant via three hydroponic experiments. The results showed that Sb(III) displayed a higher toxicity than Sb(V) to the plant which accumulated much more Sb in its tissues under Sb(III) exposure than that under Sb(V) exposure. Under Sb(III) exposure, most of absorbed Sb was found to be Sb(III) in the shoots and roots; however when plants were exposed to Sb(V), most of absorbed Sb in this rice plant was Sb(V). Only two kinds of endogenous hormones were detected as abscisic acid (ABA) and salicylic acid (SA). The addition of Sb(III) significantly increased the content of ABA but Sb(V) did not, probably suggesting the higher toxicity of Sb(III) than Sb(V) might be due to the stimulation of ABA content. The addition of Sb(III) significantly increased the concentration of oxalic acid but decreased the concentrations of formic, acetic and maleic acids. Sb(V) also enhanced the oxalic acid concentration at 20 mg L-1 Sb(V) treatment level but reduced the concentrations of formic and acetic acids. Different forms of Sb dose-dependently increased the content of pectin, but significantly enhanced the content of lignin in cell wall. Different forms of Sb induced oxidative stress, but rice plant triggered the activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX) to counteract the oxidative stress.