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Gari is a crisp and crunchy West African food made from grated cassava with the excess liquid dried out. It is a major food security product consumed by most households and students in second cycle institutions in West African. Gari production is an important source of livelihood for many women in the informal sector in Ghana. It serves as a vital avenue for value addition to cassava, thus helping to address the problem of post-harvest losses and generating income for producers. This study assessed the financial performance and constraints in gari production in Kumasi, Ghana. Primary data from a cross-sectional survey of 46 gari producers who were identified using snowball sampling technique was used. Descriptive statistics, profitability indicators, and a 5-point Likert scale were used to analyse the primary data. Results showed that gari production is predominantly done by women 30-75 years old with a mean age of 50 years. Majority of producers had no formal education (57%) and had been in production for an average of 24 years. It was found that gari production in Kumasi is financially profitable, with all the profitability indicators employed showing positive returns on inputs employed in production, although the values were less competitive relative to other producers' values elsewhere. The profit margin was favourable at 22%, return on capital employed (ROCE) at 29% and operating expense ratio at 76%. The relatively low ROCE of 29% compared with the opportunity cost of capital (31%) by commercial banks in the study area indicates the underutilization of producers' capital in gari production. Key constraints identified in the gari production business were seasonality and high cost of cassava. Adoption of cost-effective management strategies and release of all year round cassava varieties could help improve gari production and livelihoods of producers and other actors along the cassava value chain. Key words: Cassava, Gari, Production, Profitability, Constraints, Women, Livelihood, Kumasi-Ghana, INTRODUCTION Processing of cassava into local products such as fufu, agbelima, agbelikaklo, and gari is vital as these foods serve as a source of nutrients and livelihood for many people [...]

The access to the enantiopure noncanonical amino acid l-phosphinothricin (l-PPT) by applying biocatalysts is highly appealing in organic chemistry. In this study, a NADH-dependent glutamate dehydrogenase from Lachnospiraceae bacterium ( Lb GluDH) was chosen for the asymmetric synthesis of l-PPT. Three flexible loops undergoing big conformational shifts during the catalysis were identified and rationally engineered following the initial mutagenesis. The enzyme's specific activity toward the key precursor of l-PPT, 2-oxo-4-[(hydroxy) (methyl) phosphinyl] butyric acid (PPO), was improved from negligible to 9 U/mg, and the K m value was reduced to 17 mM. The computational analysis showed that the modified loops broadened the enzyme's narrow tunnels, allowing the substrate to access the binding pocket and get closer to the crucial residue D165, thereby enhancing the catalytic process. Utilizing the variant as the catalyst, the preparation of l-PPT achieved a 100% conversion rate within 60 min, coupled with a stereoselectivity exceeding 99.9%, demonstrating its practical capacity for industrial application. Similar enhancement in catalytic activity was obtained applying the same strategy to a typical NADH-dependent GluDH from Pyrobaculum islandicum ( Pis GluDH), indicating the effectiveness of our strategy for the protein engineering of GluDHs targeted to the biosynthesis of unnatural compounds.

Sb(III) oxidation by microorganisms plays a key role in the geochemical cycling of antimony and is effective for bioremediation. A previously discovered novel Sb(III)-oxidizing bacteria, Phytobacter sp. X4, was used to elucidate the response patterns of extracellular polypeptides (EPS), antioxidant system, electron transfer and functional genes to Sb(III) under anaerobic conditions. The toxicity of Sb(III) was mitigated by increasing Sb(III) oxidation capacity, and the EPS regulated the content of each component by sensing the concentration of Sb(III). High Sb(III) concentrations induced significant secretion of proteins and polysaccharides of EPS, and polysaccharides were more important. Functional groups including hydroxyl, carboxyl and amino groups on the cell surface adsorbed Sb(III) to block its entry. Hydroxyl radicals and hydrogen peroxide were involved in anaerobic Sb(III) oxidation, as revealed by changes in the antioxidant system and electron spin resonance (EPR) techniques. qPCR confirmed that proteins concerning nitrate and antimony transfer, antimony resistance and antioxidant system were regulated by Sb(III) concentration, and the synergistic cooperation of multiple proteins conferred high antimony resistance to X4. The adaptive antimony resistance mechanism of Phytobacter sp. X4 under anaerobic conditions was revealed, which also provides a reference value for bioremediation method of antimony contamination in anaerobic 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 © 2024 Elsevier B.V. All rights reserved.)

Toxic element pollution of soils emanating from smelting operations is an escalating global concern due to its severe impact on ecosystems and human health. In this study, soil samples were collected and analyzed to quantify the risk contributions and delineate the spatial risk footprints from smelting emissions for 8 toxic elements. A comprehensive health risk contribution and delineation framework was utilized, consisting of Positive matrix factorization (PMF), spatial interpolation, an advanced Bayesian isotope mixing model via Mixing Stable Isotope Analysis in R (MixSIAR), and distance-based regression. The results showed that the mean concentrations of As, Cd, Cu, Hg, Pb, and Zn exceeded the background levels, indicating substantial contamination. Three sources were identified using the PMF model and confirmed by spatial interpolation and MixSIAR, with contributions ranked as follows: industrial wastewater discharge and slag runoff from the smelter site (48.9 %) > natural geogenic inputs from soil parent materials (26.7 %) > atmospheric deposition of dust particles from smelting operations (24.5 %). Among the identified sources, smelter runoff posed the most significant risk, accounting for 97.9 % of the non-carcinogenic risk (NCR) and 59.9 % of the carcinogenic risk (CR). Runoff also drove NCR and CR exceedances at 7.8 % and 4.7 % of sites near the smelter, respectively. However, atmospheric deposition from smelting emissions affected soils across a larger 0.8 km radius. Although it posed lower risks, contributing just 1.1 % to NCR and 22.6 % to CR due to the limited elevation of toxic elements, deposition reached more distant soils. Spatial interpolation and distance-based regression delineated high NCR and CR exposure hotspots within 1.4 km for runoff and 0.8 km for deposition, with exponentially diminishing risks at further distances. These findings highlight the need for pathway-specific interventions that prioritize localized wastewater containment and drainage controls near the smelter while implementing broader regional air pollution mitigation measures., 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.)

Electrogenic biofilms in bioelectrochemical systems (BES) are critical in wastewater treatment. Industrial effluents often contain cobalt (Co 2+ ); however, its impact on biofilms is unknown. This study investigated how increasing Co 2+ concentrations (0-30 mg/L) affect BES biofilm community dynamics, extracellular polymeric substances, microbial metabolism, electron transfer gene expression, and electrochemical performance. The research revealed that as Co 2+ concentrations increased, power generation progressively declined, from 345.43 ± 4.07 mW/m 2 at 0 mg/L to 160.51 ± 0.86 mW/m 2 at 30 mg/L Co 2+ . However, 5 mg/L Co 2+ had less effect. The Co 2+ removal efficiency in the reactors fed with 5 and 10 mg/L concentrations exceeded 99% and 94%, respectively. However, at 20 and 30 mg/L, the removal efficiency decreased substantially, likely because of reduced biofilm viability. FTIR indicated the participation of biofilm functional groups in Co 2+ uptake. XPS revealed Co 2+ presence in biofilms as CoO and Co(OH) 2 , indicating precipitation also aided removal. Cyclic voltammetry and electrochemical impedance spectroscopy tests revealed that 5 mg/L Co 2+ had little impact on the electrocatalytic activity, while higher concentrations impaired it. Furthermore, at a concentration of 5 mg/L Co 2+ , there was an increase in the proportion of the genus Anaeromusa-Anaeroarcus, while the genus Geobacter declined at all tested Co 2+ concentrations. Additionally, higher concentrations of Co 2+ suppressed the expression of extracellular electron transfer genes but increased the expression of Co 2+ -resistance genes. Overall, this study establishes how Co 2+ impacts electrogenic biofilm composition, function, and treatment efficacy, laying the groundwork for the optimized application of BES in remediating Co 2+ -contaminated wastewater., 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 work studied the vertical migration characteristics of Cd in soil profiles from a zinc smelting site under the influence of simulated reclaimed water containing NaCl and Na 2 SO 4 . The isothermal adsorption curves of Cd in the soils of miscellaneous fill and weathered slate well fitted the Freundlich and Langmuir models, with R 2 ranging from 0.991 to 0.998. The maximum adsorption capacity of Cd in the soils decreased significantly under the salt ion treatments with NaCl and Na 2 SO 4 . After leaching, the Cd concentrations in the leachates and Cd contents in the subsoil layers of 10-60 cm followed the order NaCl treatment > Na 2 SO 4 treatment > CK (p < 0.05), suggesting that the salt ions promoted the vertical migration of exogenous Cd. The proportion of coarse particles (> 0.02 mm) decreased, while that of fine particles (< 0.02 mm) increased under salt ion treatments (p < 0.05). The morphological characterization indicated that salt ions accelerated the erosion and fragmentation of coarse particles to form fine particles. The use of reclaimed water to flush smelting sites may increase the risk of Cd migration with small-sized soil particles from the soil to groundwater., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Stream sediments from mine area are a converging source of water and soil pollution. The risk and development trends of metal(loid)s pollution in sediments from an abandoned arsenic-containing mine were studied using modelling techniques. The results showed that the combined techniques of geographic information system (GIS), random forest (RF), and numerical simulation (NS) could identify risk sources and diffusion trends of metal(loid)s in mine sediments. The median values of As, Cd, Hg, and Sb in sediments were 5.01, 3.02, 5.67, and 3.20 times of the background values of stream sediments in China, respectively. As (14.09%) and Hg (18.64%) pollution in mine stream sediments were severe while As is the main potential risk source with a strong spatial correlation. High-risk blocks were concentrated in the landfill area, with the surrounding pollution shows a decreasing trend of "step-type" pollution. The risk correlation between Hg and As (55.37%) in the landfill area is high. As a case of arsenic, the diffusion capacity of As within 500m is strong and stabilizes at 1 km when driven by the flows of 0.05, 0.5, and 5 m 3 /s, respectively. With the worst-case scenario flow (86 m 3 /s), it would take only 147 days for the waters within 3 km to become highly polluted. The high pollution levels in a stream under forecast of different distance intervals (500, 1500, 2000 m) within 6.5 km is arrived at approximate 344, 357, and 384 days, respectively. The study suggested the combined technique of GIS, RF, and NS can serve the risk source identification of contaminated sites and risk forecast of toxic element diffusion in emergency situations., 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 Ltd. All rights reserved.)

Penicillin G acylase (PGA) is a key biocatalyst for the enzymatic production of β-lactam antibiotics, which can not only catalyze the synthesis of β-lactam antibiotics but also catalyze the hydrolysis of the products to prepare semi-synthetic antibiotic intermediates. However, the high hydrolysis and low synthesis activities of natural PGAs severely hinder their industrial application. In this study, a combinatorial directed evolution strategy was employed to obtain new PGAs with outstanding performances. The best mutant βF24G/βW154G was obtained from the PGA of Achromobacter sp., which exhibited approximately a 129.62-fold and a 52.55-fold increase in specific activity and synthesis/hydrolysis ratio, respectively, compared to the wild-type AsPGA. Thereafter, this mutant was used to synthesize amoxicillin, cefadroxil, and ampicillin; all conversions > 99% were accomplished in 90-135 min with almost no secondary hydrolysis byproducts produced in the reaction. Molecular dynamics simulation and substrate pocket calculation revealed that substitution of the smallest glycine residue at βF24 and βW154 expanded the binding pocket, thereby facilitating the entry and release of substrates and products. Therefore, this novel mutant is a promising catalyst for the large-scale production of β-lactam antibiotics., 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 Inc. All rights reserved.)

Microorganisms are widely used in large-scale pollution remediation due to their rapid reproduction and low cost. In this study, bioremediation batch experiments and characterization methods were adopted to investigate the mechanism of FeMn oxidizing bacteria on the immobilization of Cd in mining soil. The results showed that the FeMn oxidizing bacteria successfully reduced 36.84 % of the extractable Cd in the soil. The exchangeable forms, carbonate-bound forms, and organic-bound forms of Cd in the soil decreased by 11.4 %, 8 %, and 7.4 %, respectively, due to the addition of FeMn oxidizing bacteria, while FeMn oxides-bound and residual forms of Cd increased by 19.3 % and 7.5 %, as compared to the control treatments. The bacteria promotes the formation of amorphous FeMn precipitates such as lepidocrocite and goethite, which have high adsorption capacity on soil Cd. The oxidation rates of Fe and Mn in the soil treated with the oxidizing bacteria reached 70.32 % and 63.15 %, respectively. Meanwhile, the FeMn oxidizing bacteria increased soil pH and decreased soil organic matter content, further decreasing the extractable Cd in the soil. The FeMn oxidizing bacteria have the potential to be used in large mining areas to assist in the immobilization of 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 © 2023 Elsevier B.V. All rights reserved.)

High levels of manganese (Mn) and other heavy metals from electrolytic manganese residue (EMR) stockpiled would be released into the environment under natural conditions. A batch-leaching test was carried out to investigate the release characteristics of heavy metals from EMR with different storage times under simulated environmental conditions such as acid rain with different pH (3.0, 4.5, 5.6, and 7.0) at contact times of 1, 2, 4, 6, and 12 h; liquid to solid ratio (L/S) (5:1, 10:1, 20:1, and 30:1); and temperature (15, 25, 35, and 45 °C). The results showed that low pH (3.0 and 4.5) and high temperature (35 and 45 °C) could significantly promote heavy metal leaching from EMRs and increasing the L/S ratio above 20:1 mL/g significantly decreased heavy metal leachate concentrations due to dilution effect. Cr, Mn, and Pb concentrations in leachate increased almost continuously throughout the leaching process, while Zn decreased slightly at the 12th hour. Meanwhile, heavy metal concentrations in EMR1 (fresh EMR) were higher than in EMR2 (out stockpiled for more than 3 months). The concentrations of Mn, Pb, and Zn in leachates from EMRs at pH 3.0 and 4.5 leaching far exceeded the allowable maximum discharge concentrations for pollutants of the integrated wastewater discharge standard in China (GB8978-1996) by 57.5-59.0, 1.3-4.3, and 1.1-1.8 and 53.5-56.0, 3.04-7.25, and 1.0-1.91 times, respectively. Additionally, the Mn concentrations from both EMR leachates at pH 7.0 were above the national safe emission threshold. The morphological structure of EMRs changed after leaching, and XRD analysis showed the disappearance of MnO 2 , SiO 2 , FeS 2 , and CaSO 4 . The XPS revealed that Cr, Mn, Pb, and Zn existed as Cr 3+ , MnO, PbSO 4 , and ZnSiO 3 , respectively, after leaching. The study concluded that Mn, Pb, and Zn from EMRS leached by acid rain might pose a high potential environmental risk. Therefore, developing appropriate disposal techniques for EMR is necessary to prevent heavy metal pollution., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The conversion of the more toxic Sb(III) into less toxic Sb(V) is an effective strategy for the treatment of antimony-contaminated sites. In this study, a strain, Phytobacter sp. X4, which can tolerate high concentrations of antimony and can use nitrate as an electron acceptor for Sb(III) oxidation under anaerobic conditions, was isolated from the deep soil of an antimony mine flotation tailing. Unlike other antimony oxidizing bacteria, X4 oxidized better under high Sb(III) concentration, and the oxidation efficiency of 10 mM Sb(III) reached the maximum at 110 h with 61.8 %. Kinetic study showed X4 yielded a V max of 1.093 μM∙min -1 and a K m of 718.2 μM. The genome of Phytobacter sp. X4 consists of a complete circular chromosome and two plasmids. In addition, X4 had more metal(loid)s resistance genes and highly expressed genes than other Phytobacter spp., reflecting its stronger adaptive advantage in harsh survival environments. We also analyzed the origin and evolution of arsB, arsC, and arsH, which may have been transferred horizontally from other species. iscR and arsH may have an important contribution to Sb(III) oxidation. Thus, Phytobacter sp. X4 has a good ability to remediate high antimony-contaminated sites and can be applied to an anaerobic 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 © 2022 Elsevier B.V. All rights reserved.)

Although Castellaniella species are crucial for denitrification, there is no report on their capacity to carry out denitrification and anode respiration simultaneously in a bioelectrochemical system (BES). Herein, the ability of a mixed inoculum of electricigenic Castellaniella species to perform simultaneous denitrification and anode respiration coupled with cathodic metals recovery was investigated in a BES. Results showed that 500 mg/L NO 3 - -N significantly decreased power generation, whereas 100 and 250 mg/L NO 3 - -N had a lesser impact. The single-chamber MFCs (SCMFCs) fed with 100 and 250 mg/L NO 3 - -N concentrations achieved a removal efficiency higher than 90% in all cycles. In contrast, the removal efficiency in the SCMFCs declined dramatically at 500 mg/L NO 3 - -N, which might be attributable to decreased microbial viability as revealed by SEM and CLSM. EPS protein content and enzymatic activities of the biofilms decreased significantly at this concentration. Cyclic voltammetry results revealed that the 500 mg/L NO 3 - -N concentration decreased the redox activities of anodic biofilms, while electrochemical impedance spectroscopy showed that the internal resistance of the SCMFCs at this concentration increased significantly. In addition, BES inoculated with the Castellaniella species was able to simultaneously perform heterotrophic anodic denitrification and cathodic metals recovery from real wastewater. The BES attained Cu 2+ , Hg 2+ , Pb 2+ , and Zn 2+ removal efficiencies of 99.86 ± 0.10%, 99.98 ± 0.014%, 99.98 ± 0.01%, and 99.17 ± 0.30%, respectively, from the real wastewater. Cu 2+ was bio-electrochemically reduced to Cu 0 and Cu 2 O, whereas Hg 0 and HgO constituted the Hg species recovered via bioelectrochemical reduction and chemical deposition, respectively. Furthermore, Pb 2+ and Zn 2+ were bio-electrochemically reduced to Pb 0 and Zn 0 , respectively. Over 89% of NO 3 - -N was removed from the BES anolyte during the recovery of the metals. This research reveals promising denitrifying exoelectrogens for enhanced power generation, NO 3 - -N removal, and heavy metals recovery in BES., 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 Ltd. All rights reserved.)

Soil particle size could intensively impact the Cd adsorption in soils. The adsorption characteristics of Cd on miscellaneous fill (MF) and weathered slate (WS), collected from a zinc smelting site, were studied by batch experiments under conditions of different initial Cd concentrations and soil particle sizes. The results showed that the adsorption kinetics of Cd for soil particles from MF and WS were well fitted with the pseudo-first-order model, and the Cd adsorption isotherms well conformed to the Freundlich model. Soil particle size had an inconspicuous influence on adsorption rate, while the adsorption capacity decreased with particle size increase. The Cd adsorption on soil particles could be due to the exchange with Fe/Al, and -OH/C=O sites were the predominant adsorption sites. The MF may cause secondary pollution risk due to its low adsorption ability for Cd in smelting sites., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The impact of nickel (Ni 2+ ) on the performance of anodic electroactive biofilms (EABs) in the bioelectrochemical system (BES) was investigated in this study. Although it has been reported that Ni 2+ influences microorganisms in a number of ways, it is unknown how its presence in the anode of a BES affects extracellular electron transfer (EET) of EABs, microbial viability, and the bacterial community. Results revealed that the addition of Ni 2+ decreased power output from 673.24 ± 12.40 mW/m 2 at 0 mg/L to 179.26 ± 9.05 mW/m 2 at 80 mg/L. The metal and chemical oxygen demand removal efficiencies of the microbial fuel cells (MFCs) declined as Ni 2+ concentration increased, which could be attributed to decreased microbial viability as revealed by SEM and CLSM. FTIR analysis revealed the involvement of various microbial biofilm functional groups, including hydroxyl, amides, methyl, amine, and carboxyl, in the uptake of Ni 2+ . The presence of Ni 2+ on the anodic biofilms was confirmed by SEM-EDS and XPS analyses. CV demonstrated that the electron transfer performance of the anodic biofilms was negatively correlated with the various Ni 2+ concentrations. EIS showed that the internal resistance of the MFCs increased with increasing Ni 2+ concentration, resulting in a decrease in power output. High-throughput sequencing results revealed a decrease in Geobacter and an increase in Desulfovibrio in response to Ni 2+ concentrations of 10, 20, 40, and 80 mg/L. Furthermore, the various Ni 2+ concentrations decreased the expression of EET-related genes. The Ni 2+ -fed MFCs had a higher abundance of the nikR gene than the control group, which was important for Ni 2+ resistance. This work advances our understanding of Ni 2+ inhibition on EABs, as well as the concurrent removal of organic matter and Ni 2+ from wastewater., (Copyright © 2022. Published by Elsevier Ltd.)

This study investigated soil microbial community in a typical gathering area of antimony mining and smelting in South China. The physical and chemical properties of different soils (mining waste dumps, flotation tailings, and smelting slag) and depths (0-20 cm, 40-60 cm, and 80-100 cm) were compared. The results showed that antimony (Sb) and arsenic (As) were the main pollutants, and their concentrations were 5524.7 mg/kg and 3433.7 mg/kg, respectively. Xanthates were found in the flotation tailings and smelting slag, and the highest concentration was 585.1 mg/kg. The microbial communities were analyzed by high-throughput sequencing, and it was shown that Proteobacteria, Acidobacteria, Chlorobacterium, Bacteroides, and Actinomycetes were the dominant taxa at the phylum level. There were obvious differences in microbial community structure in different sites. The dominant microorganism in the mining site was Chujaibacter. Subgroup&#95;2&#95;unclassified and Gemmatimonadaceae&#95;unclassified were the prevalent microorganisms in the flotation and smelting sites, respectively. As, Sb, and xanthates were the main factors affecting the diversity and composition of bacteria in the flotation tailings and smelting slag areas. Therefore, this study provides experimental guidance and a theoretical basis for soil antimony pollution quality assessment, biological treatment, and environmental remediation., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Identifying sources and transport routes of heavy metals in soil is necessary for pollution control. This study integrated principal component analysis (PCA), positive matrix factorization (PMF), and geographic information system (GIS) mapping to identify the sources, transport routes, and apportion heavy metals in soil based on land uses around a smelting site. The results revealed that the mean concentrations of As, Hg, Cd, Pb, Zn, and Cu in the soil exceeded their background values except for Cr, Mn, and Fe, which were slightly higher. According to the mean I geo values, the soils were most polluted with As, Cd, Pb, and Cu, followed a decreasing order of grassland (1.71, 2.38, 2.10, and 1.73) > agricultural land (0.632, 2.32, 1.19, and 1.08) > forestland (0.255, 0.952, 0.654, and 0.148). Smelter emissions and soil parent materials were the primary sources of heavy metals. The PCA and PMF factor hotspots visualized by GIS were mostly distributed within the smelting site, slag and wastewater runoff areas, and in the dominant wind direction. The GIS based PCA and PMF results confirmed that As, Cd, Pb, Cu, and Zn were transported mainly by surface runoff and atmospheric deposition, while Hg was mostly from atmospheric deposition. Grassland and agricultural land soils received heavy metals from surface runoff and atmospheric deposition, while forestland soils only received from atmospheric deposition. The integrated approach was useful in identifying the sources, transport routes, and contributions of the heavy metals among different land uses, thereby assisting policymakers in understanding the sources and transport routes of heavy metals in the soil around smelting areas., 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.)