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Nanoplastics (<1 μm) can serve as a transport vector of environmental pollutants (e.g., heavy metals) and change their toxicities and bioavailabilities. Up to date the behaviors of adsorption and desorption heavy metals on/off nanoplastics are largely unknown. Herein, polymeric membrane potentiometric ion sensors are proposed for in-situ assessment of the real-time kinetics of heavy metal adsorption and desorption on/off nanoplastics. Results show that nanoplastics can adsorb and release heavy metals in a fast manner, indicating their superior ability in transferring heavy metals. The adsorption behaviors are closely related to the characteristics of nanoplastics and background electrolytes. Particle aggregation and increases in salinity and acidity suppress the adsorption of heavy metals on nanoplastics. The desorption efficiencies of different heavy metals are Pb 2+ (31 %) < Cu 2+ (40 %) < Cd 2+ (97 %). Our proposed method is applicable for the detection of the plastic pollutants with size <100 nm and of the samples with high salinities (e.g., seawater). This work would provide new insights into the assessment of environmental risks posed by nanoplastics and heavy metals., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The widespread presence of microplastics and nanoplastics (MPs/NPs) in the environment has become a critical public health issue due to their potential to infiltrate and affect various biological systems. Our review is crucial as it consolidates current data and provides a comprehensive analysis of the cardiovascular impacts of MPs/NPs across species, highlighting significant implications for human health. By synthesizing findings from studies on aquatic and terrestrial organisms, including humans, this review offers insights into the ubiquity of MPs/NPs and their pathophysiological roles in cardiovascular systems. We demonstrated that exposure to MPs/NPs is linked to various cardiovascular ailments such as thrombogenesis, vascular damage, and cardiac impairments in model organisms, which likely extrapolate to humans. Our review critically evaluated methods for detecting MPs/NPs in biological tissues, assessing their toxicity, and understanding their behaviour within the vasculature. These findings emphasise the urgent need for targeted public health strategies and enhanced regulatory measures to mitigate the impacts of MP/NP pollution. Furthermore, the review underlined the necessity of advancing research methodologies to explore long-term effects and potential intergenerational consequences of MP/NP exposure. By mapping out the intricate links between environmental exposure and cardiovascular risks, our work served as a pivotal reference for future research and policymaking aimed at curbing the burgeoning threat of plastic pollution., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

This paper summarizes the colonization dynamics of biofilms on microplastics (MPs) surfaces in aquatic environments, encompassing bacterial characteristics, environmental factors affecting biofilm formation, and matrix types and characteristics. The interaction between biofilm and MPs was also discussed. Through summarizing recent literatures, it was found that MPs surfaces offer numerous benefits to microorganisms, including nutrient enrichment and enhanced resistance to environmental stress. Biofilm colonization changes the surface physical and chemical properties as well as the transport behavior of MPs. At the same time, biofilms also play an important role in the fragmentation and degradation of MPs. In addition, we also investigated the coexistence level, adsorption mechanism, enrichment, and transformation of MPs by environmental pollutants mediated by biofilms. Moreover, an interesting aspect about the colonization of biofilms was discussed. Biofilm colonization not only had a great effect on the accumulation of heavy metals by MPs, but also affects the interaction between particles and environmental pollutants, thereby changing their toxic effects and increasing the difficulty of MPs treatment. Consequently, further attention and research are warranted to delve into the internal mechanisms, environmental risks, and the control of the coexistence of MPs and biofilms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

High-spatiotemporal-resolution rainfall data are vital for investigating local terrestrial water cycles. Although remote-sensing satellite retrieval of precipitation products effectively reproduces spatial patterns of rainfall, it suffers from low spatial resolution. To overcome such limitations, a two-step downscaling approach is proposed here. First, 80 % of the meteorological-station data is utilized to calibrate the original Global Precipitation Measurement (GPM) data, enhancing the correlation between GPM and station data. Subsequently, utilizing elevation, slope, aspect, the normalized difference vegetation index (NDVI), wind direction, water vapor, and land surface temperature, as well as slope and aspect correction factors, as independent variables, multiscale geographically weighted regression (MGWR) and temporal lag MGWR (TL-MGWR) models were constructed. Through the aforementioned steps, downscaled monthly and daily precipitation data for the geographic region under investigation in 2022 at a spatial resolution of 0.01° were obtained. Our findings indicate that selectively employing suitable MGWR or TL-MGWR models on a monthly basis can effectively downscale monthly GPM rainfall data. The downscaled (original) monthly precipitation data exhibited a correlation of 0.94 (0.768), with a mean absolute error (MAE) of 16.233 mm/month, root-mean-square error (RMSE) of 27.106 mm/month, and bias of -0.043. Similar enhancement was likewise noted in daily precipitation, displaying a correlation coefficient of 0.863 (0.318) for downscaled (original) data, and a RMSE of 3.209 mm/day, MAE of 1.082 mm/day, and bias of -0.06. The downscaled results show a correlation increase of 0.172 monthly and 0.545 daily, with MAE reductions of 18.43 mm/month and 1.658 mm/day, RMSE reductions of 26.172 mm/month and 4.183 mm/day, and bias reductions of 82.7 % and 56.8 %. In summary, the data after downscaling, both for monthly and daily datasets, was markedly improved in accuracy. The proposed downscaling method is applicable for reconstructing high-resolution grid data in the complex terrain of the southwest China highland canyon area., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Flue gas desulfurization gypsum (FGDG), a solid waste produced during sulfur removal in coal-fired power plants, has applications in saline-alkali soil amelioration due to its function of calcium‑sodium ion exchange. Existing research has focused on the use of gypsum to improve saline-alkali soils in non-coastal areas. However, coastal areas are not only extensively salinized, but an important source of methane, and surprisingly, FGDG may assist to decrease methane formation mainly by the action of sulfate radical. This is the first critical review to systematically discuss the effects of FGDG on both saline-alkali soil improvement and carbon emission control in tidal flats, including application status, amendment principles, environmental risks and methane emission control. After adding FGDG, soil salinization degree was weakened via adjusting soil structure, pH, exchangeable sodium percentage and electric conductivity, introduction of nutrients also promotes crop growth. The optimal FGDG dosage in tidal flats seems to be higher (>2 %) than that in non-coastal areas (<1 %). Its environmental risks regarding heavy metals and eutrophication are evaluated safe. In tidal areas, more methane is produced in hot seasons and ebb tides. Plants and invertebrates also promote methane release. FGDG controls methane production by promoting the activity of sulfate-reducing bacteria and inhibiting methanogens. Considering methane flux levels and seawater erosion, FGDG use in low tidal beach needs more research, while that in high and middle tidal beach is recommended. This review will expand applications and appropriate use of FGDG for reducing carbon emission and improving ecological services in coastal areas., Competing Interests: Declaration of competing interest The authors declare no conflict interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Among various remediation methods for organic-contaminated soil, thermal desorption stands out due to its broad treatment range and high efficiency. Nonetheless, analyzing the contribution of factors in complex soil remediation systems and deducing the results under multiple conditions are challenging, given the complexities arising from diverse soil properties, heating conditions, and contaminant types. Machine learning (ML) methods serve as a powerful analytical tool that can extract meaningful insights from datasets and reveal hidden relationships. Due to insufficient research on soil thermal desorption for remediation of organic sites using ML methods, this study took organic pollutants represented by polycyclic aromatic hydrocarbons (PAHs) as the research object and sorted out a comprehensive data set containing >700 data points on the thermal desorption of soil contaminated with PAHs from published literature. Several ML models, including artificial neural network (ANN), random forest (RF), and support vector regression (SVR), were applied. Model optimization and regression fitting centered on soil remediation efficiency, with feature importance analysis conducted on soil and contaminant properties and heating conditions. This approach enabled the quantitative evaluation and prediction of thermal desorption remediation effects on soil contaminated with PAHs. Results indicated that ML models, particularly the RF model (R 2  = 0.90), exhibited high accuracy in predicting remediation efficiency. The hierarchical significance of the features within the RF model is elucidated as follows: heating conditions account for 52 %, contaminant properties for 28 %, and soil properties for 20 % of the model's predictive power. A comprehensive analysis suggests that practical applications should emphasize heating conditions for efficient soil remediation. This research provides a crucial reference for optimizing and implementing thermal desorption in the quest for more efficient and reliable soil remediation strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study aims to investigate the influence of seasonal variations on Volatile fatty acids (VFAs) production from food waste (FW) and to quantify their impact. Results of batch experiments with external pH control indicated that the properties of FW exhibited significant seasonal variations and were markedly different from kitchen waste (KW). The spring group demonstrated the highest VFA concentration and VFA/SCOD, at 31.24 g COD/L and 92.20 % respectively, which were 1.22 and 1.27 times higher than those observed in the summer season. The combined proportion of acetic acid and butyric acid accounted for 81.10 % of the total VFAs in spring, suggesting the highest applicability to the carbon source. The VFA content of all seasonal groups in descending order was butyric acid, propionic acid and acetic acid. Carbohydrates, along with spicy and citrusy substances, promoted the conversion of total VFA and butyric acid, while proteins and lipids favored the production of acetic acid and propionic acid., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

The co-contamination of pesticide residues and mycotoxins in agricultural products is a global concern, with the potential for cumulative and synergistic damaging effects, imposing substantial health and economic burdens to the public. The dosage-sensitive and simultaneous detection of multiple pollutants, with a heightened sensitivity in real samples, poses a significant demand and challenge. Herein, we propose a portable detection method integrating surface-enhanced Raman scattering (SERS)-with lateral flow immunoassay (LFIA), offering high sensitivity and multiplex analysis capabilities. This approach enables the simultaneous detection of imidacloprid (IMI), pyraclostrobin (PYR) and aflatoxin B1 (AFB1) through a single test strip. Utilizing the immune-specific binding between antigen and antibodies, we immobilised antibody- conjugated SERS nanotags on three test lines of the strips to generate Raman signal amplification in the proposed biosensor. Accurate quantitative analysis was performed by measuring the SERS signal intensity on the test lines. The limits of detection were 8.6 pg/mL for IMI, 97.4 pg/mL for PYR and 8.9 pg/mL for AFB1, exhibiting sensitivities 12-fold, 102-fold and11-fold higher than the colorimetric signals, respectively. Importantly, the SERS-LFIA immunosensor demonstrated robust performance when applied to real samples, yielding recoveries ranging from 86.16 % to 115.0 %, with relative standard deviation values below 8.67 %. These results underscore the excellent stability, high selectivity and reliability the proposed SERS-LFIA immunosensor. Consequently, it holds promise for the detection of multiple pesticides and mycotoxins in both environmental and agricultural samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Washing method has attracted much attention in the research of municipal solid waste incineration (MSWI) fly ash treatment and resource utilization. However, the controlled leaching of heavy metals and the extraction of recyclable calcium in the washing process are still blank. Acid controlled washing was conducted with different acids, concentrations, times and temperatures to extract calcium while inhibiting heavy metals. The mechanism was investigated by reaction kinetics calculation and washed fly ash characterization. The high Ca concentration of 37,420 mg/L while the low heavy metal concentrations of around or <1 mg/L were achieved at 25 °C for 60 min under a liquid-solid ratio (L/S) of 3/1 in 1.5 M HCl. The reaction kinetics of acid controlled washing conformed the layer diffusion control. The results of X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectrum (EDS) analysis indicated that the rate-limiting step was the diffusion of ions through the product layer. Simultaneously, the washing solution enriched in Ca, Na and K and the washed fly ash, which met the standard requirements (HJ 1134-2020) for leach toxicity, both had the potential for further resource utilization., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Priming effect (PE) plays a crucial role in regulating the decomposition of soil organic matter (SOM). Multiple empirical results have shown that nitrogen (N) and phosphorus (P) addition can significantly alter the direction and intensity of PE, which may significantly affect carbon turnover in grasslands, especially in alpine meadows that are sensitive to N and P enrichment. To evaluate the PE responses to N and/or P addition, we conducted an incubation experiment by adding 13 C-labeled glucose and nutrient additions (+N, +P, and +NP) in soils collected from an alpine meadow. The soils were incubated for 30 days and soil/microbial properties and enzyme activities were measured. Partial correlation and linear regression analyses were then performed to investigate their correlations with PE. The results showed that mean PE intensity among all treatments was 0.61 mg C g -1 soil or 1.35 (ratio). Nitrogen addition increased PE intensity, which was attributed to the better match between soil resources and microbial demands and enhanced enzyme activities. However, the PE intensity in P-addition soils was lower than that in control soils. This discrepancy may be related to the P-induced decrease of N availability and stronger microbial C/N imbalance. No significant response of PE intensity to NP addition was detected, and this could be explained by the offset of positive N effects and negative P effects on microbial decomposition. In this experiment, N or P addition altered the PE intensity by mediating the match between soil C:N:P ratio and microbial demands, which supported the stoichiometric decomposition hypothesis. Overall, our study highlights the importance of considering the C, N and P coupling in regulating PE, and underscores the need for further investigation into the effects of soil P on microbial activity and SOM decomposition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

After deposition on the topsoil, microplastics (MPs) may be vertically migrated to deeper soil layers over time or eventually enter the groundwater system, leading to more widespread environmental and ecological issues. However, the vertical distribution of MPs in natural soils are not yet fully understood. In this study, we collected soil profiles (0-100 cm) from four different land use types on the west bank of Taihu Lake in China to investigate the vertical distribution and weathering characteristics of MPs. The average abundance of soil MPs followed the pattern of paddy field (490 ± 82 items/kg) > dryland (356 ± 55 items/kg) > tea garden (306 ± 32 items/kg) > woodland (171 ± 27 items/kg) in the 0-10 cm layer, and the abundance of MPs decreased linearly with soil depth (r = -0.89, p < 0.01). Compared to tea garden and woodland, MPs in dryland and paddy field have migrated to deeper soil layers (80-100 cm). The carbonyl index of polyethylene and polypropylene MPs increased significantly with soil depth (r = 0.96, p < 0.01), with values of 0.58 ± 0.30 and 0.54 ± 0.33, respectively. The significant negative correlation between MPs size and carbonyl index confirmed that small-sized MPs in deeper soil layers originated from the weathering and fragmentation of MPs in topsoil. The results of structural equation model showed that roots and soil aggregates may act as filters during the vertical migration of MPs. These findings contribute to a better understanding of the environmental fate of MPs in soil and the assessment of associated ecological risks., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Bioproduction is considered a promising alternative way of obtaining useful and green chemicals. However, the downstream process of biomolecules has been one of the major difficulties in upscaling the application of bioproducts due to the high purification cost. Acid precipitation is the most common method for purifying biosurfactants from the fermentation broth with high purity. However, the use of strong acids and organic solvents in solvent extraction has limited its application. Hence, in this study, a new strain of Bacillus velezensis PhCL was isolated from phenolic waste, and its production of amylase had been optimized via response surface methodology. After that, amylase and biosurfactant were purified by sequential ammonium sulfate precipitation and the result suggested that even though the purified crude biosurfactant had a lower purification fold compared to the acid precipitation, the yield was higher and both enzymes and biosurfactant also could be recovered for lowering the purification cost. Moreover, the purified amylase and crude biosurfactant were characterized and the results suggested that the purified crude biosurfactant would have a higher emulsion activity and petroleum hydrocarbon removal rate compared to traditional surfactants. This study provided another approach for purifying bioactive compounds including enzymes and biosurfactants from the same fermentation broth and further explored the potential of the crude purified biosurfactant in the bioremediation of polycyclic aromatic hydrocarbons and petroleum hydrocarbons., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Pyrogenic carbon (PC) including black carbons and engineered carbons can mediate the extracellular electron transfer to facilitate the biogeochemical reaction with organic pollutants. Yet, the role of carbon structures and iron minerals on PC-mediated microbial degradation is still lacking of understanding. Herein, we studied the electrochemical properties of PCs produced from varied feedstock with regards to the mediated degradation of p-nitrophenol (PNP) by Shewanella putrefaciens CN32 in anoxic system. Mediated degradation by PCs was enhanced by facilitating extracellular electron transfer through oxygenated group and graphitic structure. Graphitic crystallites improved the electron-accepting capacity (as suggested by I D /I G and EAC) and diminished the electrochemical impedance (as suggested by Rct), contributing to PNP degradation under the anoxic system. Furthermore, more interfacial adsorption was conducive to the mediated reduction by the graphitic structure on PCs of high-temperature. In the presence of iron minerals, both hematite and goethite significantly facilitated PC-mediated degradation, which could be ascribed to the enhancement of the electron-donating capacity of microorganism and the accumulation of the reductive-state PCs by the interaction with generated Fe(II). This work paves a feasible way to the technical design on the remediation of phenolic contaminants by PC-mediated microbial degradation in environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Soil microplastic (MP) pollution has recently become increasingly aggravated, with severe consequences being generated. Understanding the spatial distribution characteristics of soil MPs is an important prerequisite for protecting and controlling soil pollution. However, determining the spatial distribution of soil MPs through a large number of soil field sampling and laboratory test analyses is unrealistic. In this study, we compared the accuracy and applicability of different machine learning models for predicting the spatial distribution of soil MPs. The support vector machine regression model with radial basis function (RBF) as kernel function (SVR-RBF) has a high prediction accuracy (R 2  = 0.8934). Among the six ensemble models, random forest (R 2  = 0.9007) could better explain the significance of source and sink factors affecting the occurrence of soil MPs. Soil texture, population density, and MPs point of interest (MPs-POI) were the main source-sink factors affecting the occurrence of soil MPs. Furthermore, the accumulation of MPs in soil was significantly affected by human activity. The spatial distribution map of soil MP pollution in the study area was drawn based on the bivariate local Moran's I model of soil MP pollution and the normalized difference vegetation index (NDVI) variation trend. A total of 48.74 km 2 of soil was in an area of serious MP pollution, mainly concentrated in urban soil. This study provides a hybrid framework that includes spatial distribution prediction of MPs, source-sink analysis, and pollution risk area identification, providing scientific and systematic methods and techniques for pollution management in other soil environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Environmental risks accumulate in cities, including polluted air and health disparities, but these risks can be reduced through scientific city planning. The purpose of this study was to investigate the global burden of premature mortality attributable to NO 2 exposure in urban areas and the role of the built environment in this regard., Methods: An approach based on health impact assessment was used to estimate the premature mortality burdens associated with NO 2 exposure in 13,169 urban areas around the world using globally gridded NO 2 and population estimates, baseline mortality, and epidemiologically derived exposure-response functions. We used the most recent WHO recommended value (i.e.,10 μg/m 3 ) as a counterfactual concentration. Finally, the relationship between the characteristics of the built environment at the city level and the burden of NO 2 -related mortality was evaluated., Results: Worldwide, 549,715(95%CI: 276204-815,023) cases of death attributable to NO 2 exposure in urban areas could be prevented if compliance with the latest WHO guideline, accounting for 2.7 % (95%CI:1.4 %-4.0 %) of total mortalities in 2019. Across cities around the world, the age-standardized mortality rate (per 100,000 people) attributable to NO 2 exposure ranged from 51.3 (95%CI:25.8-76.0) in Central Asia to 3.4(95%CI: 1.7-5.1) in Oceania. Although there was a significant decrease in premature mortality attributable to NO 2 exposure globally, considerable regional heterogeneity exists, with cities in Central Asia and Andean Latin America in particular exhibiting an upward trend. Further, we discovered a positive association between population density and street connectivity with mortality attributable to NO 2 . While the increase in green and blue space were significantly associated with a lower NO 2 -associated mortality., Conclusion: The findings of this study provided a comprehensive understanding of the premature mortality burden due to NO 2 in cities throughout the world and the role that urban planning policies can play in reducing the health burden associated with air pollution., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

China has the largest worldwide cumulative installed photovoltaic (PV) capacity, which is expected to be 1300 GW in 2050. Industrial production, population explosion and fossil fuel combustion would reduce the surface solar radiation that could be received by PV panels. However, it is still a problem to explore the integrated effects of socio-economic and air pollutant emissions on PV power potential in China. In this study, climate change impact on PV power potential in 2023-2100 were assessed using the Coupled Model Intercomparison Project Phase 6 (CMIP6) model, combining Shared Socio-economic Pathway (SSPs) and Representative Concentration Pathways (RCPs). The validation results with ground-based surface solar radiation measurements collected from 17 China Meteorological Administration (CMA) stations showed that the Meteorological Research Institute Earth System Model version 2-0 (MRI-ESM2-0) attained a better performance with mean correlation coefficients (R), Root Mean Square Error (RMSE), and Mean Absolute Error (MAE) of 0.85, 35.80 Wm -2 and 29.37 Wm -2 , respectively. Then, the MRI-ESM2-0 model was selected to analyze the spatial and temporal variations in PV power potential. PV power potential decreased significantly in SSP585 ranging from 192.71 Wm -2 to 189.96 Wm -2 in 2023-2100 corresponding to the growing resource intensity and fossil fuel dependency. In contrast, if China continues on the path of sustainable and low-carbon development and keeps temperature rise to about 1.5 °C by 2100, PV power potential will increase by 1.36-5.90 Wm -2 . Meanwhile, the effects of climatological factors on PV power potential were analyzed by Empirical Orthogonal Function (EOF) method. Results indicated that surface solar radiation had the highest contribution of >50 %, and the contribution of aerosols and cloud cover was about 20 %. This study is conducive to the full utilization of solar resources and has important implications for the future formulation of solar energy policy in China., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

In order to reduce the residue of buoy-beads and solve the problem of pollution caused by high flocculant consumption, SAMs 1 (sodium alginate microspheres) with sodium alginate were used as the raw material to harvest microalgae for the first time. In addition, during the manufacturing of SAMs, the re-frying oil was used as the dispersion system, which not only reduced the cost, but also provided new ideas for the treatment of re-frying oil. Response surface methodology was used to explore the influence of different factors and the interaction of variables, and the harvesting process was optimized using the multi-objective optimization. Based upon the calculation of XDLVO (extended Derjaguin-Laudau-Verwey-Overbeek) theory and the characterization of Fourier Transform Infrared Spectroscopy, the harvesting mechanism of buoy-bead flotation method was clarified. The results showed that the combination of SAMs and a small amount of aluminum sulfate could replace air flotation and traditional buoy-bead flotation with solid particles as buoy-beads to harvest C. vulgaris (Chlorella vulgaris). For the multi-objective optimization with harvesting efficiency as the priority, the predicted pH, the concentrations of aluminum sulfate and buoy-beads and the dilution factor had values of 8.25, 56.09 mg/L, 17.46 mL/L, and 2.15, respectively. In the validation experiment, the harvesting efficiency and the enrichment ratio of C. vulgaris could reach the values of 97.51 % and 1.97 %, respectively. For the validation experiment of reverse optimization with focusing on enrichment ratio, the harvesting efficiency and the enrichment ratio of C. vulgaris had the values of 93.78 % and 2.65 %, respectively. The essence of improving the harvesting mechanism was the combination of carboxyl and hydroxyl groups between C. vulgaris and SAMs and the adsorption of positive ions by specific proteins on the surface of C. vulgaris to reduce electrostatic repulsion., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Biochar is known to accelerate composting process and improve the quality of end-products. However, its effects on bioconversion of organic waste by black soldier fly larvae (BSFL) remains largely unexamined. To investigate the effects of corn straw biochar (CS-BC) on bioconversion of soybean dregs (SD) by BSFL, SD was amended with four different dosages of CS-BC [0%, 2%, 5%, and 8% (w/w)] and digested by BSFL for ten days. The results indicated that the peak values of single larva wet weight in the treatments amended with CS-BC were advanced by 2-3 days and the reduction rate of SD increased from 72.09% to 85.37% with the increasing dosage of CS-BC. Meanwhile, SD mixed with 2%, 5% and 8% of CS-BC decreased ammonia (NH 3 ) emission by 2.7%, 3.6% and 18.0%, respectively. The nitrous oxide (N 2 O) emissions reduced (-23.6%, -29.1% and -49.2%) with 2%, 5% and 8% CS-BC additions, respectively. In addition, the residual nitrogen of SD‑nitrogen proportionally increased with CS-BC application (28.3%, 28.6%, 30.1% and 35.0% for application at the dosage of 0%, 2%, 5% and 8%, respectively). Based on the comprehensive evaluation of bioconversion performance, alleviation of pollutant gas emission, and nitrogen conservation, we recommend the introduction of 8% (w/w) CS-BC during bioconversion of SD by BSFL. This study confirmed the feasibility of CS-BC as an amendment for the BSFL-based bioconversion system., Competing Interests: Declaration of competing interest The authors declare that we have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

This review summarizes major findings over the last decade related to N-nitrosodimethylamine (NDMA) formed upon ozonation, which was regarded as highly toxic and carcinogenic disinfection by-products. The reaction kinetics, chemical yields and mechanisms were assessed for the ozonation of potential precursors including dimethylamine (DMA), N,N-dimethylsulfamide, hydrazines, N-containing water and wastewater polymers, dyes containing a dimethylamino function, N-functionalized carbon nanotubes, guanidine, and phenylurea. The effects of bromide on the NDMA formation during ozonation of different types of precursors were also discussed. The mechanism for NDMA formation during ozonation of DMA was re-summarized and new perspectives were proposed to assess on this mechanism. Effect of hydroxyl radicals (•OH) on NDMA formation during ozonation was also discussed due to the noticeable oxidation of NDMA by •OH. Surrogate parameters including nitrate formation and UV 254 after ozonation may be useful parameters to estimate NDMA formation for practical application. The strategies for NDMA formation control were proposed through improving the ozonation process such as ozone/hydrogen peroxide, ozone/peroxymonosulfate and catalytic ozonation process based on membrane pores aeration (MEMBRO 3 X)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Se unevenly distributed in soils due to variations of geology and anthropogenic input, which results in different effects on earthworms. The effects of Se were characterized by analyzing the growth and metabolism responses of earthworms after exposure to three different concentrations of Na 2 SeO 3 . The results showed that except the possible growth promotion at 5 mg/kg, low and middle-level exposure to Na 2 SeO 3 (0.3-10 mg/kg) did not significantly affect the growth of earthworms. While a significant inhibition effect on growth was observed in the high-level exposure group (30-70 mg/kg). There was an inflection point for Se performing promotion to inhibition effects on earthworm growth. To investigate the metabolic response of earthworms, a novel HPLC-ESI-MS (High Performance Liquid Chromatography-Electrospray Ionization-Mass Spectrometry) method was used to determine sensitive biomarkers. Selenium exposure significantly altered the metabolism of seven essential amino acids, namely tyrosine, leucine, phenylalanine, valine, alanine, glycine, and lysine, and two selenoamino acids, namely selenomethionine and methylselenocysteine. The overall metabolism level of earthworms was not affected at low exposure concentrations, but was affected at medium and high exposure concentrations. The metabolic pathways that integrated the selenocompound metabolism and the tricarboxylic acid cycle from the perspective of energy supply and demand were affected by Na 2 SeO 3 exposure. The derived reactive oxygen species at high exposure concentrations were probably the reason for the growth inhibition effect of Se on earthworms. This study provides biochemical insights into the effects of Na 2 SeO 3 on earthworms and suggests that an Se concentration of about 2.3 mg/kg is appropriate for soil organism health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The Himawari-8 aerosol algorithm was updated to version 3 (V30). However, no study has evaluated its performance. The purpose of this study is to verify and to compare version 2.1 (V21) and V30 aerosol products, to explain which factor dominates the aerosol optical depth (AOD) error, and to provide recommendations for aerosol product usage. The AOD accuracy of V30 was better than that of V21, with a higher correlation coefficient (R) and a higher expected error (EE&#95;DT). The V30 AOD metrics (including R, EE&#95;DT, and the root mean square error) exceeded those of V21 on more than 69% of the AERONET sites and its bias from MODIS AOD was smaller than that of V21 AOD. However, the V30 AOD does not meet the metric of EE&#95;DT > 0.66. The analysis results suggest that aerosol type parameters (primarily the Ångström exponent (AE)) may be the dominant factor determining the AOD error. This reveals the direction of H8 algorithm improvement. More than 59% of the H8 AE value meets the expected error but they do not capture the variety (R < 0.3). The FMF and SSA retrieved by H8 performed poorly. The V30 AOD performs best in Japan and South Korea (83.3% of AERONET sites meet the EE&#95;DT > 0.66 requirement) and has better data accuracy in the morning. Therefore, we recommend V30 AOD morning data to users in Japan and South Korea regions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Increasing temperature plays important roles in affecting plant and soil microbial communities as well as ecological processes and functions in terrestrial ecosystems. However, mechanisms of warming influencing soil carbon dynamics associated with plant-microbe interactions remain unclear. In this study, open-top chambers (OTCs) experiments were carried out to detect the responses of plants, soil microbes, and SOC contents, physical fractions (by particle-size fractionation) and chemical composition (by solid-state 13 C NMR spectroscopy) to warming in two alpine swamp meadows (Kobresia humilis vs K. tibetica) on the Tibetan Plateau. Our results showed that four years of warming had significant influences on plant belowground biomass, microbial community and SOC contents in the K. humilis swamp meadow, but had much weaker or minor effects in the K. tibetica swamp meadow with water-logged status and lower level of warming. In the K. humilis swamp meadow, warming increased microbial biomass, C-hydrolysis gene abundance and N-acetylglucosaminidase enzyme activity. These positive effects of warming on microbial biomass and functions further increased soil dissolved inorganic nitrogen and alleviated the nitrogen limitation for plant growth, potentially leading to higher plant biomass. Therefore, increases in SOC and particulate organic carbon (POC) under warming were likely attributed to the higher C input with promoted plant biomass overweighting the simultaneous higher C degradation and release in the K. humilis swamp meadow. Conversely, warming marginally reduced soil alkyl C, which was likely associated with enhanced decomposition by fungi and gram-positive bacteria. Overall, the increases in unprotected POC and decreases in recalcitrant alkyl C demonstrate the sensitivity of SOC physical fractions as well as chemical composition to climate warming in the K. humilis alpine swamp meadow, and suggest that the overall stability of SOC might be lower despite the gain in the content of SOC after climate warming in this alpine swamp meadow., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: A warming climate throughout the 21st century makes ambient high temperature exposure a major threat to population health worldwide. Mitigating the health impact of high temperature requires a timely, comprehensive and reliable assessment of disease burden globally, regionally and temporally., Aim: Based on Global Burden of Disease (GBD) Study 2019, this study aimed to evaluate the disease burden attributable to high temperature from various epidemiology perspectives., Methods: A three-stage analysis was undertaken to investigate the number and age-standardized rates of death and disability-adjusted life years (DALY) attributable to high temperature from GBD Study 2019. First, we reported the high temperature-related disease burden for the whole world and for different groups by gender, age, region, country and disease. Second, we examined the temporal trend of the disease burden attributable to high temperature from 1990 to 2019. Finally, we explored if and how the high temperature-related disease burden was modified by a number of country-level indicators., Results: Globally, high temperature accounted for 0.54% of death and 0.46% of DALY in 2019, equating to the age-standardized rates of death and DALY (per 100,000 population) of 3.99 (95% uncertainty interval (UI): 2.88, 5.93) and 156.81 (95% UI: 107.98, 261.98), respectively. In 2019, the high temperature-related DALY and death rates were the highest for lower respiratory infections, although they showed a downward trend. In contrast, during 1990-2019, high temperature-related non-communicable diseases burden exhibited an upward trend. Meanwhile, the disease burden attributable to high temperature varied spatially, with the heaviest burden in regions with low sociodemographic index (SDI) and the lightest burden in regions with high SDI. In addition, high temperature-related disease burden appeared to be higher in a country with a higher population density and PM 2.5 concentration background but lower in a country with a higher density of greenness., Conclusion: This study for the first time provided a comprehensive understanding of the global disease burden attributable to high temperature, underscoring the policy priority to protect human health worldwide in the context of global warming with particular attention to vulnerable countries or regions as well as susceptible population and diseases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The concentrated solar thermal power (CSP) industry is projected to expand rapidly in China in the next 30 years. However, anthropogenic aerosol emissions reduce direct radiation (R dir ) reaching the surface, resulting in the losses of potential CSP electricity production in China. In this study, we applied various models to estimate daily R dir , and the results showed that the gradient boosting with categorical features support (CatBoost) model was superior to other models, and coefficient of determination (R), root mean square error (RMSE) and mean absolute error (MAE) were 0.96, 1.99 MJ m -2 day -1 and 1.92 MJ m -2 day -1 , respectively. We used R dir data set at 839 stations across China derived by CatBoost model to calculate losses of the potential CSP electricity production from aerosol emissions. The results showed that the potential CSP electricity production decreased by 12.9% (136 kWh) on average at provincial level during 1961-2015. It is plausible that air quality will continue to improve from now due to the success of previous air pollution control measurements and the commitment to the United Nations of "Carbon Neutrality". It was found that returning to direct radiation levels in 1960s could yield a 15.8% increase in potential CSP electricity production, equal to 28.4-79 TWh with the expected 2050 CSP installation capacities. The corresponding economic benefits could reach 17.1-56.9 billion RMB in 2050. The findings in this study will be beneficial for siting, designing and optimizing CSP systems in China., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Developing models that can accurately simulate groundwater level is important for water resource management and aquifer protection. In particular, machine learning tools provide a new and promising approach to efficiently forecast long-term groundwater table fluctuations without the computational burden of building a detailed flow model. This study proposes a multistep modeling framework for simulating groundwater levels by combining the wavelet transform (WT) with the long short-term memory (LSTM) network; the framework is named the combined WT-multivariate LSTM (WT-MLSTM) method. First, the WT decomposes the groundwater level time series (i.e., the training stage) into a self-control term and a set of external-control terms. Second, Pearson correlation analysis reveals the correlations between the influencing factors (i.e., river stage) and the groundwater table, and the multivariate LSTM model incorporating external factors is built to simulate the external-control terms. Third, the spatiotemporal evolution of the groundwater level is modeled by reconstructing the sequence of each term of the groundwater level time series. Methodological applications in the Liangshui River Basin, Beijing, China and the Cibola National Wildlife Refuge along the lower Colorado River, United States, show that the combined WT-MLSTM model has a higher simulation accuracy than the standard LSTM, MLSTM, and WT-LSTM models. A comparison between the combined WT-MLSTM model and support vector machine (SVM) also demonstrates the advantage of the proposed model. Additional comparison between model forecasts and observed groundwater levels shows the model predictability for short-term time series. Further analysis reveals that the applicability of the combined WT-MLSTM model decreases with increasing distance between the groundwater well and adjacent river channel, or with the increasing complexity of the changing groundwater level patterns, which may be driven by additional controlling factors. This study therefore provides a new methodology/approach for the rapid and accurate simulation and prediction of groundwater level., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Microsensors are able to accurately quantify nitrous oxide (N 2 O) emissions in microenvironments at high spatio-temporal resolution; yet, limited studies have been conducted on agricultural soils due to the inability to obtain electrical signal under conditions of low soil moisture. This study improved the calibration of a microelectrode for measuring N 2 O emissions from agricultural soil. The microelectrode was applied to evaluate the effect of long-term fertilization with mineral fertilizer (NPK), complemented with pig manure (MNPK), straw (SNPK), or without fertilizer (CK), all with and without urea addition, on N 2 O emissions from the soil, with explicit separation of the rhizosphere and the bulk soil compartments. The use of soil solution instead of pure water for calibration of the microelectrode doubled the signal and significantly improved the sensor sensitivity. The optimal electrolytic concentration of the soil solution, expressed as water: soil ratio, was found at the maximum vertex of the quadratic equation fitted on the slope values of the calibration equations for different soil solutions. The application of the calibrated microelectrode revealed significantly higher N 2 O emission from the rhizosphere compared to the bulk soil, accounting for 60% of the total emission. For the bulk soil, MNPK significantly increased N 2 O emissions compared to SNPK and NPK, whereas the differences between these treatments for the rhizosphere soil were insignificant. The statistical modeling revealed significant relation of the N 2 O emission with soil inorganic nitrogen contents and an additive effect of treatment (MNPK and SNPK), urea addition and rhizosphere soil. This study provides novel insights into the use of microelectrodes for measuring N 2 O emissions from the soil microenvironment and also points on the rhizosphere compartment and the management practices of agroecosystems able to reduce the N 2 O emission from agriculture., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Dicarboxylic acids are a group of highly oxidized components, which can provide insights into the formation mechanism and aging process of secondary organic aerosols (SOA). Based on the 12-h day and night PM 2.5 samples collected in downtown Beijing in January, April, July and October of 2017, dicarboxylic acids and relevant components were measured to investigate their seasonal variation pattern and sources. High concentrations of the identified organic acids were observed, following the decreasing order of July > January > October > April. The high fractions of phthalic acid and maleic acid in January indicated severe aromatic SOA pollution during the sampling period in winter, and the high malonic acid to succinic acid and malic acid to succinic acid ratios in July suggested strong photochemical formation over the sampling period in summer. Based on the calculation of principle component analysis and multiple linear regression, water-soluble organic acids were mainly formed from the aerosol aging process during the sampling periods except for January, while water-soluble organic carbon (WSOC) mostly originated from combustion sources. Correlation analysis was conducted between the CO-normalized concentrations of organic acids and PM 2.5 , O 3 , as well as the meteorological parameters. The results suggested that gas-phase photooxidation contributed significantly to the formation of these organic acids during the entire sampling period, and the aqueous-phase process played an important role over the severe haze event in January. Our results also suggested that the intensity of photooxidation and the aging degree of SOA were enhanced along with the reduction of PM 2.5 in Beijing in recent years., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Reclaimed water is in huge demand in water-deficient cities. However, nitrogen, pharmaceuticals and personal care products (PPCPs) are frequent contaminants in reclaimed water that are probable to bring environmental risks. To develop a technology for safe reclaimed water production, in this study, a renovated filter that integrates solid-phase denitrification (SPD) with biodegradable polymer poly-3-hydroxybutyrate-co-hydroxyvalerate (PHBV) and granular activated carbon (GAC) adsorption (SPD-GAC filter) was proposed and applied to remove nitrogen and target PPCPs (metoprolol and diclofenac) simultaneously. The influences of different ratio of the filled PHBV and GAC, and the hydraulic retention time (HRT) on the removal performances were investigated. The results showed that the filter with PHBV/GAC = 1 (25 cm PHBV/25 cm GAC) simultaneously achieved an average NO 3 - -N removal efficiency of about 95% with no accumulation of ammonia and nitrite, and an average removal efficiency of PPCPs of about 80%. Compared with PHBV-based SPD system, the integrated SPD-GAC filter significantly improved the control of carbon release and the PPCP removals. SPD-GAC filter also exhibited a strong tolerance for the variation of influent NO 3 - -N loading rate, achieving a highest denitrification rate of 0.76-0.82 g N·(L·d) -1 . The integrated SPD-GAC filter proves to be a promising technology for the simultaneous removal of nitrogen and PPCPs from the secondary effluent., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The emerging contaminants, in particular pharmaceuticals and personal care products and environmental estrogens, have been received global concerns in recent years. Nanofiltration (NF) as an advanced tertiary treatment technology can be a reliable and potential tool for micropollutants removal. However, the influence of operation conditions of NF system to micropollutants rejections in an engineering application, is still lacking. Here, a pilot-scale NF system was set up to investigate its removal efficiencies to 49 micropollutants under different operation conditions by treating actual municipal wastewater. The results showed that the rejections of positively and neutrally charged micropollutants with molecular weight higher than 250 g mol -1 were both higher than 80%. Besides, most negatively charged micropollutants were also rejected higher than 80% under different operation conditions. The rejections of most micropollutants increased with temperature decreased from 25 °C to 13 °C, which was primarily ascribed to decrease of pore size of NF membrane at low temperature. Compared with the water recovery rate of 80%, lower rejections of micropollutants were observed with lower water recovery rate of 60%. Except for sulfamethoxazole, the risk quotients of other detected 20 micropollutants in NF effluent were all lower than 1.0, showing medium or no risks to aquatic organisms. This study might aid understanding the performance of micropollutants rejections by NF in actual engineering application and could give guideline to the implementation of NF technology in future advanced treatment processes., Competing Interests: Declaration of competing interest There is no conflicts of interest in this research., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The climatic characteristics of solar Ultraviolet radiation (UV) are of vital important for the climate change and photochemical reactions. High-quality records of solar UV radiation are the premise for solar UV researches and applications, but solar UV radiation observations are sparse around the world. Among all wavelength of UV radiations, only UVA (0.315-0.400 nm) and UVB (0.280-0.315 nm) could reach the earth surface. This study attempted to develop a novel efficient physically broadband parameterization (hereafter, FASTUV) for estimating surface solar UV radiation (0.280-0.400 μm) in all-sky conditions based on Leckner's spectral model for calculating shortwave solar radiation, using MERRA&#95;2 reanalysis data. The Quadratic polynomial formula and artificial neural networks were used to calculate the cloud transmittance for UV, using sunshine durations measurements at 2474 CMA stations. The surface solar UV radiation measurements at 29 CERN (The Chinese Ecosystem Research Network) stations were used for validating the estimated UV values. The result showed the FASTUV model could be used for estimating UV values with high accuracy, strong robustness and fast speed. Then, the spatial and temporal variation of surface solar UV radiation in China were revealed. The result indicated that the Qinghai Tibetan Plateau and the Palmier Plateau has always been the areas with highest UV values, while the Northeastern China is the area with the lowest UV values. Meanwhile, the FASTUV model have been packaged into a software namely 'FASTUV&#95;V1.0'. We provide the executable file of FASTUV model in publicly available repository: https://doi.org/10.6084/m9.figshare.11409666., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Anaerobic digestion (AD) with thermal hydrolysis pretreatment has been attracted widespread attention in recent years due to its high efficiency. However, few studies focus on systematical comparison of the downstream AD processes for thermal hydrolyzed sludge and their corresponding microbial community compositions, especially on those at pilot scale and above. Thus, this study systematically compared the long-term performance and microbial communities of two pilot-scale anaerobic reactors for thermal hydrolyzed sludge digestion under mesophilic and thermophilic conditions. The results presented that mesophilic anaerobic digestion (MAD) showed a better performance of methane production than thermophilic anaerobic digestion (TAD). The hydraulic retention time (HRT) needed to be longer than 12 days in MAD while 20 days in TAD to achieve the relatively high methane production, which could be explained by that the ammonia nitrogen accumulation especially the free ammonia determined in TAD was higher than that in MAD at all HRTs, emerging an inhibition of methane yield in TAD. High-throughput Illumina sequencing results demonstrated a more diverse microbial community in MAD than that in TAD. TAD was mediated by a suite of thermophiles, such as Coprothermobacter and Methanothermobacter, while taxa harbored in MAD mostly belonged to Bacteroidetes and relatively broad types of methanogens. In addition, hydrogenotrophic methanogens were the predominant of archaea communities in both digesters probably due to the relatively high concentration of ammonia nitrogen., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Composting is an important technology to treat biowastes and recycle nutrients, but incurs nitrogen (N) losses that lower the value of the final products and cause pollution. Technologies aimed at reducing N losses during composting have inconsistent outcomes. To deepen insight into mitigation options, we conducted a global meta-analysis based on 932 observations from 121 peer-reviewed published studies. Overall, N losses averaged 31.4% total N (TN), 17.2% NH 3 -N, and 1.4% N 2 O-N, with NH 3 -N accounting for 55% of TN losses. The primary drivers affecting N losses were composting method, type of biowaste, and duration of composting. N losses were significantly impacted by the carbon-to-nitrogen (C/N) ratio of the input materials (feedstock of nutrient dense biowastes and C-rich bulking agents), moisture content and pH. Our analysis revealed N-conserving optima with C/N ratios of 25-30, 60-65% moisture content and pH 6.5-7.0. In situ mitigation technologies that control feedstock and processing conditions reduced average N losses by 31.4% (TN), 35.4% (NH 3 -N) and 35.8% (N 2 O-N). Biochar and magnesium-phosphate salts emerged as the most effective N-conserving strategies, curbing losses of TN by 30.2 and 60.6%, NH 3 by 52.6 and 69.4%, and N 2 O by 66.2 and 35.4% respectively. We conclude that existing technologies could preserve ~0.6 Tg of biowaste-N globally, which equates to 16% of the chemical N-fertilizer used in African croplands, or 39% of the annual global increases of 1.58 Tg fertilizer-N. However, the adoption of N-conserving technologies is constrained by a lack of knowledge of best practice, suitable infrastructure, policies and receptive markets. To realize an N-conserving composting industry that supports sustainable practices and the circular nitrogen economy, stakeholders have to act collectively. Benefits will include lowering direct and indirect greenhouse gas emissions associated with agriculture, and facilitating the recarbonization of soils., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Although jarosite and visible light are important factors for the formation of acid mine drainage (AMD), the effects of combined jarosite and visible light on chalcopyrite biodissolution have not been explored until now. In order to fill this knowledge gap, the combined effects of jarosite and visible light on chalcopyrite dissolution mediated by Acidithiobacillus ferrooxidans were investigated. The results indicated that jarosite and visible light could significantly accelerate chalcopyrite biodissolution, thus releasing more copper ions, iron ions and producing more acid. This in turn suggests enhanced generation of AMD under these conditions. Biodissolution results, mineral surface morphology, mineralogical phase and elemental composition analyses revealed that the promotion of chalcopyrite dissolution by additional jarosite and visible light was mainly attributed to the acceleration of ferric iron/ferrous iron cycling and the inhibition of the formation of a passivation layer (jarosite and S n 2- /S 0 ) on the surface of chalcopyrite. This study provides a better understanding of the effects of jarosite and visible light on chalcopyrite biodissolution. In the future, the influences of jarosite and visible light on chalcopyrite dissolution should be considered in AMD evaluation to ensure reliability., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Water-soluble organic acids are widely involved in various atmospheric physicochemical processes and appear as an important fraction of atmospheric aerosols. Nineteen water-soluble organic acids in 12-h PM 1 , PM 2.5 and PM 10 samples collected in urban Beijing during haze episodes in winter and spring of 2017 were identified to investigate their characteristics and secondary formation mechanism. The molecular distributions of water-soluble organic acids as well as the high ratio of phthalic acid (Ph)/azelaic acid (C 9 ) indicated severe aromatic secondary organic aerosol pollution during the haze episodes, especially in winter. The diurnal patterns, size distributions, and concentration ratios of specific organic acids were investigated to reveal the pollution characteristics and possible sources of major organic acids in particulate matter in Beijing during haze events. Multiple linear regression was used to tentatively quantify the relative contributions of photochemical oxidation and aqueous-phase oxidation to the formation of total water-soluble organic acids in PM 1 , PM 2.5 and PM 10 during haze episodes. The formation mechanism of sulfate and nitrate was also investigated for comparison. Different from the secondary formation of sulfate, the secondary formation of water-soluble organic acids showed enhanced contribution of gas-phase photochemical oxidation though the aqueous-phase oxidation was the dominant process. CAPSULE: Molecular analyses of organic acids in PM 1 , PM 2.5 and PM 10 in Beijing during haze periods revealed their pollution characteristics, possible sources and formation mechanism., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Butane-1,4-bis(dodecyl dimethyl ammonium bromide) (gBDDA) and dodecyl trimethyl ammonium bromide (DTMA) in same stoichiometric amounts were applied to modify montmorillonite (Mt) under microwave and ultrasound conditions. The composition and structure of products were obtained through multiple characterizations including XRD, FTIR, TG/DTG, SEM, TEM, and N 2 adsorption/desorption measurements, and the adsorption performance of chromate and phenol on these products were also investigated. Intercalations of gBDDA and DTMA into interlayer space of Mt were observed, but the amount of anchored modifier on the external surface was larger for gBDDA compared with DTMA when the stoichiometric amount of modifier larger than 1.0 times cation exchange capacity of Mt was added. Although there was no significant difference in morphology among products, the interlayer space distance, specific surface area, and pore size distribution were closely associated with the species and amount of applied modifier. Adsorption of phenol on products through partition mechanism relied on not only organic content, but also the configuration of modifier. Meanwhile, adsorption of chromate mainly depended on the presence of counter ion (bromide), which accounted for the high adsorption capacity and initial adsorption rate on gOMt-0.75. The fitting parameters of adsorption results using pseudo-second order model and Freundlich model suggested that gBDDA-modified Mt could sequester phenol or chromate in the faster manner with higher affinity. Compared with the conventional surfactant such as DTMA, the study revealed that, using gemini surfactant such as gBDDA to modify Mt would significantly reduce or even has the potential to eradicate the secondary pollution by modifier release during adsorption process. This study provides a new direction for Mt modification intended to be used as adsorbents to treat polluted water with high standards such as drinking water., (Copyright © 2018 Elsevier B.V. All rights reserved.)

To quantify regional sources contributing to submicron particulate matter (PM1) pollution in haze episodes, on-line measurements combining two modeling methods, namely, positive matrix factorization (PMF) and backward Lagrangian particle dispersion modeling (LPDM), were conducted for the period of one month in urban Nanjing, a city located in the western part of Yangtze River Delta (YRD) region of China. Several multi-day haze episodes were observed in December 2013. Long-range transport of biomass burning from the southwestern YRD region largely contributed to PM1 pollution with more than 25% of total organics mass in a lasting heavy haze. The LPDM analysis indicates that regional transport is a main source contributing to secondary low-volatility production. The high-potential source regions of secondary low-volatility production are mainly located in areas to the northeast of the city. High aerosol pollution was mainly contributed by regional transport associated with northeastern air masses. Such regional transport on average accounts for 46% of total NR-PM1 with sulfate and aged low-volatility organics being the largest fractions (>65%)., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Quantitative understanding of farmers' behaviour in pesticide use is critical to enhance sustainability of chemical pest control and protect farmers' health and the environment. However, reports on the levels of knowledge and awareness of farmers and the practices of pesticide use are often insufficient. Here, we conducted a comprehensive analysis on the effects of knowledge and awareness of farmers as well as the influence of the associated stakeholders (i.e. pesticide retailers and the government) on farmers' behaviour in pesticide use by using a detailed survey of 307 agricultural households (79 grain farms, 65 fruit farms, 53 vegetable farms and 110 mixed-crop farms) in the Wei River basin in northern China. Eight protective behaviours (PBs) were exhibited by farmers. Careful and safe storage of pesticides, changing clothes or showering after applying pesticides, and reading instructions of the container labels before application were the most frequent PBs. Vegetable and fruit farmers had higher levels of education and knowledge than grain farmers, but the former were less willing to reduce pesticide use because of fear of low profits and lack of trust in the government and pesticide retailers. The PBs of farmers were strongly affected by the perception of the consequences of their behaviour (standardised path coefficient, SPC=0.42) and the level of farmers' knowledge (SPC=0.33). Pesticide retailers and the government had a moderate and weak influence, respectively, on farmers' PBs, suggesting a large gap of trust among farmers, pesticide retailers, and the government. Training and supervising retailers, educating farmers, and improving information transparency across farmers, pesticide retailers and the staff of the Agricultural Extension and Technology Service are recommended for bridging the gap of trust between farmers and the associated stakeholders as well as for promoting the use of PBs among farmers., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Prediction of the biodegradability of organic pollutants is an ecologically desirable and economically feasible tool for estimating the environmental fate of chemicals. In this paper, linear and nonlinear relationships between biological oxygen demand (BOD) and molecular descriptors/fragments have been investigated for 1130 organic chemicals. Significant relationships have been observed between the simple molecular descriptors and %BOD for some homologous compounds, but not for the whole set of compounds. Electronic parameters, such as E(HOMO) and E(LUMO), are the dominant factors affecting the biodegradability for some homologous chemicals. However, other descriptors, such as molecular weight, acid dissociation constant and polarity still have a significant impact on the biodegradation. The best global model for %BOD prediction is that developed from a chain-based fragmentation scheme. At the same time, the theoretical relationship between %BOD and molecular descriptors/fragments has been investigated, based on a first-order kinetic process. The %BOD is nonlinearly, rather than linearly, related to the descriptors. The coefficients of determination can be significantly improved by using nonlinear models for the homologous compounds and the whole data set. After analysing 1130 ready and not ready biodegradable compounds using 23 simple descriptors and various fragmentation schemes, it was revealed that biodegradation could be well predicted from a chain-based fragmentation scheme, a decision tree and a %BOD model. The models were capable of separating NRB and RB with an overall accuracy of 87.2%, 83.0% and 82.5%, respectively. The best classification model developed was a chain-based model but it used 155 fragments. The simplest model was a decision tree which only used 10 structural fragments. The effect of structures on the biodegradation has been analysed and the biodegradation pathway and mechanisms have been discussed based on activating and inactivating fragments., (Copyright © 2012 Elsevier B.V. All rights reserved.)