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The co-occurrence of cadmium (Cd) pollution and selenium (Se) deficiency commonly exists in global soils, especially in China. As a result, there is great interest in developing practical agronomic strategies to simultaneously achieve Cd remediation and Se mobilization in paddy soils, thereby enhancing food quality/safety. To this end, we conducted a field-plot trial on soils having high geological background levels of Cd (0.67 mg kg-1) and Se (0.50 mg kg-1). We explored 12 contrasting fertilizers (urea, potassium sulfate (K2SO4), calcium-magnesium-phosphate (CMP)), amendments (manure and biochar) and their combinations on Cd/Se bioavailability. Soil pH, total organic carbon (TOC), soil available Cd/Se, Cd/Se fractions and Cd/Se accumulation in different rice components were determined. No significant differences existed in mean grain yield among treatments. Results showed that application of urea and K2SO4 decreased soil pH, whereas the CMP fertilizer and biochar treatments increased soil pH. There were no significant changes in TOC concentrations. Three treatments (CMP, manure, biochar) significantly decreased soil available Cd, whereas no treatment affected soil available Se at the maturity stage. Four treatments (CMP, manure, biochar and manure＋urea＋CMP＋K2SO4) achieved our dual goal of Cd reduction and Se enrichment in rice grain. Structural equation modeling (SEM) demonstrated that soil available Cd and root Cd were negatively affected by pH and organic matter (OM), whereas soil available Se was positively affected by pH. Moreover, redundancy analysis (RDA) showed strong positive correlations between soil available Cd, exchangeable Cd and reducible Cd with grain Cd concentration, as well as between pH and soil available Se with grain Se concentration. Further, there was a strong negative correlation between residual Cd/Se (non-available fraction) and grain Cd/Se concentrations. Overall, this study identified the primary factors affecting Cd/Se bioavailability, thereby providing new guidance for achieving safe production of Se-enriched rice through fertilizer/amendment management of Cd-enriched soils.

Biochars and zeolites are highly suitable for soil restoration due to their ability to enhance soil structure, improve nutrient and water retention, regulate pH levels and remove various impurities. Both materials offer significant benefits for soil management and environmental health, effectively transforming degraded soils into productive land. They are usually characterized by high specific surface area, which is essential for improving capacity of soil sorption complex. The presented literature review compares effects generated by biochars and zeolites on sorption capacity of different soil types toward metal ions, pharmaceuticals, pesticides, and pollutants. So far, numerous researchers have examined biochars and zeolites as soil amendments, but only some of them have tested their simultaneous addition or application with polymers. Nevertheless, based on the reports on date, it can be concluded that incorporating biochar and zeolite into soil remediation practices is a promising strategy to improve soil quality and promote environmental sustainability. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThe use of woody species for the remediation of heavy metal-contaminated soils is an environmentally friendly and economically viable strategy. This study investigates the phytoextraction abilities of 15 woody species for copper, lead and zinc in contaminated soil. The results indicated that all species showed phytoextraction ability, with metal concentrations varying from 5.59 to 27.45 mg·kg−1 for Cu, 2.79 to 16.75 mg·kg−1 for Pb and 22.13 to 185.72 mg·kg−1 for Zn in the stem tissues depending on the species. Pterocarya stenoptera, Paulownia fortunei and Salix matsudana were identified as the top performers in terms of overall phytoextraction capacity. Notably, their capacity to transport zinc exceeded that of copper and lead. The enrichment of copper, lead and zinc in the soil showed a synergistic effect in the presence of heavy metal. The distribution of heavy metals within plant tissues was affected by water content and the inherent toxicity of metals. The study highlights that the accumulation of tree biomass and water content in the stem play a significant role in determining the amount of heavy metals phytoextracted. This insight offers a quick method for the rapid selection of woody species for phytoremediation in urban soils contaminated with heavy metals.Dendroremediation is an important ecological remediation measure, and efficient selection strategies for woody species have become the key to the application of phytoremediation engineering. The extraction ability of 15 woody species for heavy metal and their correlation with wood characteristics were tested and analyzed by field trials. The study highlighted that the accumulation of tree biomass and water content in the stem play a significant role in determining the amount of heavy metals phytoextracted. This insight offers a quick method for selecting woody species for remediation in urban soils contaminated with heavy metals. [ABSTRACT FROM AUTHOR]

ABSTRACT The Oryctes rhinoceros (Scarabaeidae: Coleoptera) is a common coleopteran insect in tropical and subtropical areas with many potential uses. Its larvae are commonly found in dead coconut trees and hay piles in the wild and are widely distributed in the northern hemisphere. This study investigates the environmental factors influencing the growth of Oryctes rhinoceros beetle larvae and provides valuable insights into their breeding conditions versus their potential applications. The research examined three key affecting factors of larval development over time, namely, moisture content, growth space and soil content. Results of a pretest run revealed that moisture content, but not the soil content, affected the larval survival greatly. A reasonable confinement on feed moisture (i.e., 30%–60%) was included in the later conducted three‐factor factorial experiment. At last, results of the factorial run suggested that: (1) for a consistent and massive larval breeding, environmental factors, setting moisture content at 60%, larval space at 100 cm3/larva and no soil addition, are deemed appropriate, (2) for nutritional purpose, setting moisture content at 60%, larval space at 300 cm3/larva and no soil addition are recommended, and (3) for soil pollution remediation, setting moisture content at 60%, larval space at 100 cm3/larva and a soil‐to‐feed (S/F) ratio of 2:1 is concluded. This study marks the first engineering breeding exploration of Oryctes rhinoceros larvae, offering practical recommendations for various research purposes and applications. [ABSTRACT FROM AUTHOR]

The consequences of climate change urgently demand the reduction of atmospheric carbon, including by sequestering carbon in soil. The glomalin-related soil proteins (GRSP) of arbuscular mycorrhizal fungi (AMF) are renowned for their soil aggregation and carbon sequestration properties. With their considerable binding abilities, GRSP can also adsorb various cations and sequester heavy metals in soil, thereby assisting in soil fertilization and remediation efforts. However, despite its benefits for soil health and climate change, the mechanisms underlying these traits in the context of soil chemistry remain unexplored. In this review, we focus on three crucial roles of GRSP—long-term carbon sequestration, soil aggregation, and soil remediation and fertility—in the context of the chemical characteristics elucidated by previous research, namely hydrophobicity, amid group glycosylation (N-glycosylation), and metal adsorption. Based on the proposed chemical mechanisms, the current review also offers insight into soil factors that may influence the persistence of GRSP. We conclude by proposing a working model for GRSP, aiming to establish a conceptual platform for future research to examine GRSP in terms of their known or novel chemical and biochemical reactions, thereby improving our understanding of this important group of soil proteins. [ABSTRACT FROM AUTHOR]

This work aims at illustrating the benefit of combining lead (Pb) biomonitoring data with toxicokinetic simulations in order to confidently identify the risk management intervention that favors the greatest reduction of blood Pb level (BLL) in children exposed to smelter emissions in a mining city from northern Quebec, Canada. The U.S. EPA's Integrated Exposure and Uptake BioKinetic (IEUBK) model was parametrized with relevant environmental concentrations data to simulate background BLL (in average Canadian children) and local BLL (in children from the concerned community). The resulting simulations were compared with corresponding BLL biomonitoring data. Next, soil and air concentrations were lowered sequentially within the IEUBK model to values specified in Quebec's environmental regulations. IEUBK simulations predicted mean BLL values that were similar to the measured biomonitoring values, for both the background (predicted: 0.56 vs observed: 0.5 µg/dL) and local BLL (1.24 vs 1.16 µg/dL). Repeating local BLL simulations with lower Pb concentration in the air or soil based on regulatory guidelines showed a much stronger impact of decreasing soil Pb as compared to air Pb. Concluding, this work shows that soil remediation should be prioritized to lower local children's BLL. Also, the combined use of case-specific environmental Pb levels and biomonitoring data can increase the level of confidence toward an IEUBK-driven identification of the most effective measure for lowering children's BLLs, in the ≤2 µg/dL domain. [ABSTRACT FROM AUTHOR]

Mangroves provide fundamental ecosystem services; however, the growing impact of human activities has resulted in increased pollution pressure, such as chemical contaminants. The redox processes are major biogeochemical players in the fate of contaminants. We investigate the effects of the redox environment on As(V) and Cr(VI) adsorbed on goethite (i.e., Fe(III)‐oxide) over 40 days of incubation in columns containing mangrove soil subjected to seawater saturation cycles. Our spectroscopic data highlighted a less Fe(III)‐ordered arrangement on goethite over time; As(V) is strongly bound to goethite, which delayed until 20 days its remobilization and reduction to As(III). After 40 days, the goethite held ∼50% of the initial As, but it was 15% as As(III). On the other hand, Cr(VI) was desorbed almost completely in less than 10 days, and the residual Cr ions bound to goethite were almost totally converted to Cr(III). Our study stresses the importance of individual time‐dependence in evaluating chemical speciation changes among potential toxic elements in wetland systems, such as mangroves and artificial wetlands designed to water treatment or soil remediation. Core Ideas: The redox processes are major biogeochemical players in wetlands.Goethite surface changes to less‐ordered structure in mangrove soils.Fast Cr(VI) mobilization in mangrove soils, however, is reduced to Cr(III).Slow As(V) release in mangrove soils, however, is reduced to As(III). [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the efficiency of the microbial rhizosphere (Canavalia ensiformis) in the phytoremediation of sulfentrazone using quantification methods (CO2 evolution, microbial biomass carbon, and metabolic quotient) and identification of bacteria (PCR-DGGE technique). The experiment was conducted in a completely randomized design, in a 2x4 factorial scheme, with four replications. The treatments were composed of rhizospheric soil (cultivated with C. ensiformis) and non-rhizosphere soil (uncultivated soil); and four levels of contamination by sulfentrazone (0, 200, 400, and 800 g ha−1 a.i.). The microbiota associated with the rhizosphere of C. ensiformis efficiently reduced sulfentrazone residues in the soil, with better performance at the dose of 200 g ha−1 a.i. Using the PCR-DGGE technique allowed the distinction of two profiles of bacteria in the rhizospheric activity of C. ensiformis. The second bacterial profile formed was more efficient in decontaminating soil contaminated with sulfentrazone residue. The microbiota associated with the rhizosphere of C. ensiformis has an efficient profile in decontaminating soils with residues equivalent to 200 g ha−1 a.i. the herbicide sulfentrazone. NOVELTY STATEMENT: Phytoremediation of soils contaminated with herbicide residues is a viable technique for decontamination of the environment. Canavalia ensiformis has an efficient profile in the decontamination of soils with residue equivalent to 200 g ha−1 a.i. of the herbicide sulfentrazone. The PCR technique and microbial respiration used to analyze the diversity and estimate the bacterial population of a soil are viable tools to evaluate the phytoremediation potential of the microbiota associated with plant species. [ABSTRACT FROM AUTHOR]

The objective of this research was to analyse soil and garden compost as a remediation medium at the foothill´s locality of the Tribeč Mountains, Southwestern Slovakia, to determine the pH/KCl, Pb, NO3−-N, NH4+-N contents in soil and soil affected by compost (the ratio 1 : 1), to evaluate the statistical significance of pH/KCl in relation to Pb and inorganic forms of nitrogen, and to find whether garden compost affects the monitored parameters. The analyses were carried out using Atomic Absorption Spectrometry, and Colorimetric and Potentiometric methods. Ascertained values of exchange reactions in soil ranged from 5.74 to 6.83 and exchange reactions in soil affected by garden compost ranged from 6.78 to 7.98. According to the calculated indices of dependencies, the development of pH/KCl values can be evaluated as moderately dynamic. The obtained results were evaluated statistically using the SAS 9.4 software method by the Spearman's correlation coefficient. The results in the observed three-year period showed that NO3−-N contents in soil had reached 14.73 mg.kg−1, NH4+-N 9.50 mg.kg−1, Nin 23.05 mg.kg−1, Pb 67.38 mg.kg−1, soil affecting by remediation medium – garden compost (the ratio 1 : 1) showed that NO3−-N contents had reached 23.93 mg.kg−1, NH4+-N 26.42 mg.kg−1, Nin 42.63 mg.kg−1, Pb 64.71 mg.kg−1 dry matter. Statistical dependence was high (P <0.01), which was demonstrated for soil pH : soil + compost Pb, soil + compost pH : soil + compost Pb. The garden compost influenced pH/KCl, reduced Pb levels, and increased the proportion of inorganic forms of nitrogen in soil. [ABSTRACT FROM AUTHOR]

Nicosulfuron residues in soil can be harmful to the environment. In this study, Klebsiella oxytoca ES5 and Klebsiella grimontii ES8 were isolated to construct the ES58 bacterial complex. The culture medium was optimized using response surface methodology, nicosulfuron degradation by ES58 reached 97.21 % in 96 h. The optimal degradation conditions were: temperature: 25℃, pH 6, initial nicosulfuron concentration: 50 mg L−1 and inoculum volume: 2 %. The two individual strains and the bacterial complex were tested for the ability of nitrogen fixation, phosphorus solubilization, potassium decomposition and iron carrier production. The results revealed that both strains and the bacterial complex had the ability to promote the growth, with bacterial complex being more capable than the two individual bacterial strains. After 28 d of bioremediation of nicosulfuron-contaminated soil by ES58, degradation rate of nicosulfuron was 90.84 % in the unsterilized soil. Furthermore, the remediation process restored the activities of catalase, invertase, dehydrogenase and urease in the soil. The ES5-specific gene budA and ES8-specific gene ldh were detected in the soil at the 28th day. ES58 exhibited different effects on the growth indexes of nicosulfuron-sensitive crops. The study provides a novel strategy for nicosulfuron degradation effective by constructing and utilizing bacterial complex. [Display omitted] • Two strains of nicosulfuron efficient degrading bacteria were isolated and identified. • The degradation characteristics of the complex bacterium ES58 were investigated. • The growth-promoting ability of the composite bacterium ES58 was determined. • Bioremediation of nicosulfuron contaminated soil by the complex bacterium ES58 was studied. [ABSTRACT FROM AUTHOR]

Presence of cadmium in soil affects the growth status of plants; research on the underlying mechanism has focused on its lethal and sublethal consequences in plants, ignoring the impacts of soil organisms. Therefore, this study designed a microorganism – earthworm – plant ecosystem, investigated the influence of Cd (0, 0.3, 1.0, and 3.0 mg kg−1) on the growth of Arabidopsis thaliana in the presence of earthworms (Eisenia fetida), and revealed the mechanisms from the perspective of altered relationships among different soil organisms. In this study, there was no significant difference in the death rate of earthworms with low Cd addition concentration, but the microorganisms in earthworms and soil microorganisms changed, abundance of Actinomycetes in soil increased, while Planctomycetes decreased, Mycobacterium in the gut of Eisenia fetida decreased under Cd stress. Microorganisms affect soil pH, which in turn affects soil physicochemical properties and the form of cadmium in soil. Compared with the control, soil pH significantly decreases under cadmium stress, Under 0.3 mg kg−1 treatment, soil total nitrogen, available phosphorus and total potassium are 181.11, 5.09, 51.90, and 7.55 mg kg−1, respectively, They were significantly higher than control group. Improved the growth environment of Arabidopsis thaliana and promoted the absorption of Cd in soil which affected the proportion of available Cd in the soil (when Cd was added at 1.0 mg kg−1, the proportion of available Cd in the soil decreased significantly from 95.05% to 49.40%). A. thaliana also absorbed more Cd, which increased Cd toxicity, and the reproductive growth of A. thaliana was enhanced, while vegetative growth was weakened.Compared with the control group (278.11 mg), the biomass of A. thaliana decreased significantly to 189.83 mg when Cd was supplemented at 0.3 mg kg−1. Therefore, the activities of and interactions among earthworms, plants, and microorganisms play important roles in reducing soil heavy metals and improving soil properties. HIGHLIGHTS: Under cadmium (Cd) stress, the relative abundance of Actinomycetes in soil increased, while Planctomycetes decreased. The relative abundance of Mycobacterium in the gut of Eisenia fetida decreased under Cd stress. Microbial changes and E. fetida activity changed soil physical and chemical properties and reduced the ratio of soil available Cd. Microorganisms and E. fetida enhanced the reproductive growth and weakened the vegetative growth of Arabidopsis thaliana. [ABSTRACT FROM AUTHOR]

Pb-contaminated soil poses inherent risks for the spread of antibiotic resistance genes (ARGs). However, few reports have investigated the distribution of lead resistance genes (LRGs), particularly their role in ARGs dynamics during Pb-contaminated soil remediation. This study explored the mechanisms driving ARGs variation under different remediation strategies. The results indicated that an increase in the total abundance of ARGs after applying montmorillonite (Imvite), the composite remediation agents of MgO and Ca(H2PO4)2 (MgO-Ca(H2PO4)2), and the composite remediation agents of montmorillonite, MgO, and Ca(H2PO4)2 (Imvite-MgO-Ca(H2PO4)2). Bioelectrochemical systems (BES) effectively reduced ARGs abundance, and when combined with Imvite-MgO-Ca(H2PO4)2, lowered the risk of ARGs proliferation linked to antibiotic deactivation. Changes in Pb concentration and pH reshaped microbial communities, impacting both LRGs and ARGs. To reduce the risk of ARGs proliferation and transmission during, various control strategies, such as modifying Pb stress, adjusting pH, and manipulating microbial community structure, have been proposed. The study provided theoretical foundation and practical strategies for controlling ARGs dissemination during the remediation of heavy metal-contaminated soil. [ABSTRACT FROM AUTHOR]

Due to potassium persulfate's excessive reaction speed and severe impact on the soil environment, slowing down the reaction rate and reducing its environmental impact is an important but challenging matter. Hence, microencapsulation technology was taken to modify potassium persulfate, and potassium persulfate microcapsules were used to remediate the PAHs-contaminated soil. The results of XRD and an infrared spectrum identified that the core material (potassium persulfate) exists after being encapsulated by the wall material (stearic acid), and there was no chemical reaction between the core material and wall material. The results of the sustained release effect and kinetic equation showed that the release rate of the potassium persulfate microcapsules was close to 60% after 48 h, and it had a good sustained-release effect compared with previous studies. The results of the radical probe revealed that the free radicals produced from potassium persulfate microcapsules activated by Fe2+ were the main reasons for the degradation of PAHs, and SO4−· played the most important major role in the degradation of PAHs, followed by ·OH, and the reducing substances also played an auxiliary role. The results also suggested that potassium persulfate microcapsules not only degraded PAHs in soil (53.6% after 72 h) but also had fewer negative effects on the environment, and they even promoted the growth and development of microorganisms and increased the germination rate of seeds due to the slow-release effect of the microcapsules. This work reveals the degradation mechanism of potassium persulfate microcapsules and provides a new amendment of potassium persulfate in the remediation of PAHs-contaminated soil. [ABSTRACT FROM AUTHOR]

Soil remediation for cadmium (Cd) toxicity is essential for successful tobacco cultivation and production. Melatonin application can relieve heavy metal stress and promote plant growth; however, it remains somewhat unclear whether melatonin supplementation can remediate the effects of Cd toxicity on the growth and development of tobacco seedlings. Herein, we evaluated the effect of soil-applied melatonin on Cd accumulation in tobacco seedlings, as well as the responses in growth, physiological and biochemical parameters, and the expression of stress-responsive genes. Our results demonstrate that melatonin application mitigated Cd stress in tobacco, and thus promoted plant growth. It increased root fresh weight, dry weight, shoot fresh weight and dry weight by 58.40%, 163.80%, 34.70% and 84.09%, respectively, compared to the control. Physiological analyses also showed significant differences in photosynthetic rate and pigment formation among the treatments, with the highest improvements recorded for melatonin application. In addition, melatonin application alleviated Cd-induced oxidative damage by reducing MDA content and enhancing the activities of enzymatic antioxidants (CAT, SOD, POD and APX) as well as non-enzymatic antioxidants (GSH and AsA). Moreover, confocal microscopic imaging confirmed the effectiveness of melatonin application in sustaining cell integrity under Cd stress. Scanning Electron Microscopy (SEM) observations illustrated the alleviative role of melatonin on stomata and ultrastructural features under Cd toxicity. The qRT-PCR analysis revealed that melatonin application upregulated the expression of photosynthetic and antioxidant-related genes, including SNtChl, q-NtCSD1, NtPsy2 and QntFSD1, in tobacco leaves. Together, our results suggest that soil-applied melatonin can promote tobacco tolerance to Cd stress by modulating morpho-physiological and biochemical changes, as well as the expression of relevant genes. [ABSTRACT FROM AUTHOR]

Phytoremediation is a technology that uses plants to break down, remove, and immobilize contaminants in surface water, shallow groundwater, and sediment to achieve cost savings compared with conventional treatments. This study describes a marshy land on an explosives manufacturing site in India that consistently reported elevated concentrations of nitrates, nitrites, ammonia, perchlorate, and lead (contaminants of potential concern—CoPC). The study also illustrates the potential for addressing the human health and environmental risks associated with the explosives manufacturing industrsy in India using innovative, sustainable, and carbon‐neutral techniques. This work focuses on reconstructed marshy lands, desedimentation, microwatershed management, and phytoremediation using Phragmites and Vetiveria species (also known as vetiver) to reduce contaminants in surface water and groundwater, improve stormwater management and carbon capture, and increase natural capital like biodiversity. The results obtained during the trial indicate that the selected indigenous species are effective and can be used to remediate sediment and shallow groundwater for many CoPC in tropical climates. Integr Environ Assess Manag 2024;20:1987–2002. © 2024 SETAC Key Points: The results obtained during the trial indicate that the selected indigenous species are effective and can be used to remediate sediment and shallow groundwater for many CoPC in tropical climates.If we drew a life cycle based on this study, it would be as follows: contaminants deposited to nature (soil) are extracted by plants (natural, no chemical intervention), and as the plants uptake the contaminants, they are harvested and turned into compost, which can again return to the soil (nature).This approach can reduce contaminants in both sediment and water, and is a low‐cost and environmentally friendly remediation alternative to more traditional methods. [ABSTRACT FROM AUTHOR]

Microbial electrochemical technologies represent innovative approaches to contaminated soil and groundwater remediation and provide a flexible framework for removing organic and inorganic contaminants by integrating electrochemical and biological techniques. To simulate in situ microbial electrochemical treatment of groundwater plumes, this study investigates Cr(VI) reduction within a bioelectrochemical continuous flow (BECF) system equipped with soil‐buried electrodes, comparing it to abiotic and open‐circuit controls. Continuous‐flow systems were tested with two chromium‐contaminated solutions (20–50 mg Cr(VI)/L). Additional nutrients, buffers, or organic substrates were introduced during the tests in the systems. With an initial Cr(VI) concentration of 20 mg/L, 1.00 mg Cr(VI)/(L day) bioelectrochemical removal rate in the BECF system was observed, corresponding to 99.5% removal within nine days. At the end of the test with 50 mg Cr(VI)/L (156 days), the residual Cr(VI) dissolved concentration was two orders of magnitude lower than that in the open circuit control, achieving 99.9% bioelectrochemical removal in the BECF. Bacteria belonging to the orders Solirubrobacteriales, Gaiellales, Bacillales, Gemmatimonadales, and Propionibacteriales characterized the bacterial communities identified in soil samples; differently, Burkholderiales, Mycobacteriales, Cytophagales, Rhizobiales, and Caulobacterales characterized the planktonic bacterial communities. The complexity of the microbial community structure suggests the involvement of different microorganisms and strategies in the bioelectrochemical removal of chromium. In the absence of organic carbon, microbial electrochemical removal of hexavalent chromium was found to be the most efficient way to remove Cr(VI), and it may represent an innovative and sustainable approach for soil and groundwater remediation. Integr Environ Assess Manag 2024;20:2033–2049. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: The research offers valuable insights that can contribute to advancing microbial electrochemical remediation systems designed to reduce Cr(VI) in water‐saturated soils.There were substantial differences from previously reported studies: acclimatization and/or adaptation and transfer of the electroactive bacterial community to Cr(VI) to a bioelectrochemical continuous flow system, no ion exchange membranes, and no nutrients and/or organic carbon added.The research was conducted to simulate most realistically the real conditions of Cr(VI)‐contaminated aquifers, in terms of solid‐to‐liquid ratio, interactions among soil phases, and physicochemical parameters (pH and electrical conductivity).The outcomes achieved in the system for Cr(VI) reduction in water‐saturated soil can demonstrate the feasibility of employing microbial electrochemical technology for the in situ treatment of contaminated aquifers, with interesting implications for economic and environmental sustainability. [ABSTRACT FROM AUTHOR]

Soil contamination is a significant environmental issue that poses a threat to human health and the ecosystems. Conventional remediation techniques, such as excavation and landfilling, are often expensive, disruptive, and unsustainable. As a result, there has been growing interest in developing sustainable remediation strategies that are cost‐effective, environmentally friendly, and socially acceptable. One such solution is phytoextraction: a nature‐based approach that uses the abilities of hyperaccumulator plants to uptake and accumulate metals and metalloids (potentially toxic elements [PTE]) without signs of toxicity. Once harvested, plant biomass can be treated to reduce its volume and weight by combustion, thus obtaining bioenergy, and the ashes can be used for the recovery of metals or in the construction industry. However, phytoextraction has shown variable effectiveness due to soil conditions and plant species specificity, which has led researchers to develop additional approaches known as assisted phytoextraction to enhance its success. Assisted phytoextraction is a remediation strategy based on modifying certain plant traits or using different materials to increase metal uptake or bioavailability. This review article provides a practical and up‐to‐date overview of established strategies and the latest scientific advancements in assisted phytoextraction. Our focus is on improving plant performance and optimizing the uptake, tolerance, and accumulation of PTE, as well as the accessibility of these contaminants. While we highlight the advantages of using hyperaccumulator plants for assisted phytoextraction, we also address the challenges and limitations associated with this approach. Factors such as soil pH, nutrient availability, and the presence of other contaminants can affect its efficiency. Furthermore, the real‐world challenges of implementing phytoextraction on a large scale are discussed and strategies to modify plant traits for successful phytoremediation are presented. By exploring established strategies and the latest scientific developments in assisted phytoextraction, this review provides valuable guidance for optimizing a sustainable, nature‐based technology. Integr Environ Assess Manag 2024;20:2003–2022. © 2024 SETAC Key Points: Assisted phytoextraction is a promising technique for the remediation of soils contaminated with potentially toxic elements.Improving plant performance and promoting the solubility of potentially toxic elements are two critical steps for increasing the efficiency of phytoextraction.To be considered a nature‐based solution, assisted phytoextraction should be integrated into a phytomanagement strategy, to ensure not only environmental but also economic and social benefits.There is a need for further insights into the key factors that control plant–bacteria and plant–fungi symbiosis involving native species to enhance phytoextraction. [ABSTRACT FROM AUTHOR]

Soil contamination by the munition explosive residues of 2,4,6-trinitrotoluene (TNT) and its metabolites resulting primarily from military operations has been identified as a threat to human health and ecosystems. Biodegradation by native plants to remove this hazardous compound or reduce its toxicity is considered a cost-effective and environmentally sound approach for the cleanup or restoration of TNT-contaminated soils. This study aims to investigate the TNT biodegradation and kinetics by two selected native grasses in the species-specific rhizosphere soils through growth chamber experiments. Native eastern gamma grass (Tripsacum dactyloides) and switchgrass (Panicum virgatum L.) were grown in soil spiked with 14C-TNT for 8 weeks. The 14C-TNT degradation and degradative metabolite profile in the rhizosphere soils were determined by liquid scintillation counter and high-performance liquid chromatography, respectively. The results indicated that both native grass species significantly enhanced the TNT degradation in the rhizosphere soils as compared with the control rhizosphere soils. More than 95% of the applied 14C-TNT was degraded in the first 7 days, and the rate then reached a steady state afterward, but less than 10% of the TNT applied was completely mineralized and transformed into CO2. The degradative reaction was found to follow second-order kinetics. Six major TNT degradative metabolites have been detected and identified in the rhizosphere soils. Overall, switchgrass appeared more effective for biodegrading TNT than eastern gamma grass. This research demonstrated that the native grass species, especially switchgrass, has the potential to mitigate the adverse human health and ecological risks of TNT-contaminated sites and can be considered an environmentally friendly, sustainable approach to safeguarding human health from TNT contamination. [ABSTRACT FROM AUTHOR]

Encapsulation and nutrient addition in bacterial formulations have disadvantages concerning cell viability during release, storage, and under field conditions. Then, the objective of this work was to encapsulate a bacterial consortium with hydrocarbon-degrading capacities in different matrices composed of cross-linked alginate/ polyvinyl alcohol /halloysite beads (M1, M2, and M3) containing nanoliposomes loaded with or without nutrients and evaluate their viability and release in a liquid medium, and soil (microcosmos). Also, evaluate their capacity to remove total petroleum hydrocarbons (TPH) for 165 days and matrices characterization. The encapsulate consortium showed a quick adaptation to contaminated soil and a percentage of removal (PR) of TPH up to 30% after seven days. All the matrices displayed a PR of up to 90% after 165 days. The matrix M2 displayed significant resistance to degradation and higher cell viability with a PR of 94%. This result supports the encapsulation of bacteria in a sustainable matrix supplemented with nutrients as a well-looked strategy for improving viability and survival and, therefore, enhancing their effectiveness in the remediation of hydrocarbon-contaminated soils. [ABSTRACT FROM AUTHOR]

Pb soil pollution poses a serious health risk to both the environment and humans. Immobilization is the most common strategy for remediation of heavy metal polluted soil. In this study, municipal sewage sludge was used as an amendment for rehabilitation of Pb-contaminated soils, for agricultural use, near a lead-acid battery factory. The passivation effect was further improved by the addition of phosphate fertilizer. It was found that the leachable Pb content in soils was decreased from 49.6 mg kg−1 to 16.1–36.6 mg kg−1 after remediation of sludge for 45 d at applied dosage of municipal sewage sludge of 4–16 wt%, and further decreased to 14.3–34.3 mg kg−1 upon extension of the remediation period to 180 d. The addition of phosphate fertilizer greatly enhanced the Pb immobilization, with leachable Pb content decreased to 2.0–23.6 mg kg−1 with increasing dosage of phosphate fertilizer in range of 0.8–16 wt% after 180 d remediation. Plant assays showed that the bioavailability of Pb was significantly reduced by the soil remediation, with the content of absorbed Pb in mung bean roots decreased by as much as 87.0%. The decrease in mobility and biotoxicity of the soil Pb is mainly attributed to the speciation transformation of carbonate, Fe-Mn oxides and organic matter bound Pb to residue Pb under the synergism of reduction effect of sludge and acid dissolution and precipitation effect of phosphate fertilizer. This study suggests a new method for remediation of Pb-contaminated soil and utilization of municipal sewage sludge resources. [ABSTRACT FROM AUTHOR]

The main cause of agricultural soil pollution that endangers human health is tannery waste. Experiments were carried out to assess the effects of green material (GM), rice straw (RS), and rice straw biochar (RSB) on Triticum aestivum L. grown in tannery effluent-contaminated soil in the district Kasur, Pakistan. The application of GM, RS, and RSB significantly (P ≤ 0.05) reduced the concentration of heavy metals (HMs) such as Cd, Pb, and Cr in amended soil. The bioaccumulation of Cd decreased by up to 59–34%, Pb by up to 58–42%, and Cr by up to 30–34% in Triticum aestivum L. shoot and roots with RSB amendment. Increased concentration of chlorophyll a by up to 74%, 30%, and 110%, chlorophyll b by up to 138%, 70%, and 225%, and carotenoids by up to 87%, 37%, and 140% was measured with GM, RS, and RSB amendment. However, reduced concentrations of SOD by up to 41%, 36%, and 72%, POD by up to 7%, 20%, and 55%, and CAT by up to 29%, 22%, and 38% were recorded with GM, RS, and RSB amendment. Data revealed that RSB was beneficial to Triticum aestivum L. growth, soil HMs remediation, and activating antioxidant enzymes. RSB can be used as a suitable amendment in the remediation of tannery polluted soil. [ABSTRACT FROM AUTHOR]

Soil contamination by heavy metals poses serious risks to human health due to their high toxicity and resistance to biodegradation, especially when they accumulate through the food chain. Soil drenching technology is one of the most promising methods for soil pollution remediation. In this research, microbubbles were introduced into the disodium ethylenediamine tetraacetate(EDTA-2Na) solution during soil drenching, combined with Polysorbate 80(TW-80) to remove heavy metals(Cu, Cd) from the soil. The microbubbles contributed to concentrating heavy metals, thus lowering their levels in the solution. The efficiency of heavy metal removal was found to be positively correlated with both time and detergent concentration, and negatively correlated with pH levels. Under conditions where the washing time was 120 minutes, EDTA-2Na concentration was 1 g/L, TW-80 concentration was 2 g/L, the solid-liquid ratio was 1:30, the gas-liquid ratio was 1:3, and the pH was maintained at 3, the removal rates for Cu and Cd were 86.67% and 85.52%, respectively. The Community Bureau of Reference (BCR) sequential extraction procedure revealed that intensive was Ahile et al., 2021 hing with microbubbles effectively eliminated acid-soluble (F1) and reducible (F2) heavy metals from the soil, thereby mitigating their detrimental effects on soil ecosystems. These insights offer a theoretical and practical foundation for employing microbubble technology in the remediation of heavy metal ion pollution in soils. [ABSTRACT FROM AUTHOR]

Contaminating the soil with heavy metals(HMs,This abbreviation is used in all subsequent content) is a serious problem.Combining the two can be a more effective solution to soil heavy metal remediation. In this paper, Detailed overview of the contaminated soil remediation in a cooperative manner by microorganisms and plants was presented.The first is the growth-promoting mechanism of microorganisms, which enhances restoration by altering the nitrogen, phosphorus, iron and phytohormones in the plant growth environment. Secondly, by reducing oxidative stress in plants and enhance heavy metals bioavailability, heavy metals can be enriched. In addition, plants can provide nutrients for microbes by releasing some organic matter, and at the same time, they can enrich HMs and provide a good environment for fungus. In general, plant growth-promoting bacteria, mycorrhizal fungi and plant growth-promoting rhizobacteria are usually combined with plants as tools for soil remediation. Finally, prominent cases of soil remediation in recent years were summarised. This review helps to understand how the most newer developments in the area of microbial-phytoremediation and will further strengthen the understanding of the mechanisms and Using microbial-plant cooperation to clean up contaminated soil,and it will make it easier to learn more about what are some of the more notable accomplishments and developments in the field in recent years, which are relevant for the expansion of this remediation methodology. [ABSTRACT FROM AUTHOR]

In recent years, organic pollution in soil has become more serious, thus timely treatment is particularly important. Persulfate technology has a good treatment effect in reducing soil organic pollutants. Analyzing the feasibility and prospects of the applications of persulfate technology in soil organic pollution is conducive to the development of soil remediation. The activation method of persulfate treatment of soil organic pollutants is as follows: thermal activation, microwave activation, ultrasound activation, alkali activation, material activation, electroactivation and photoactivation. The influencing factors of persulfate treatment of soil organic pollutants are as follows: coexisting substance effects, persulfate initial concentrations, treatment time, soil temperature, soil pH value and soil moisture content. Persulfate technology can effectively deal with the problem of organic pollution in soil, which can be developed in the following aspects: (i) Coupling different persulfate activation technologies; (ii) Applicating activated persulfate with non-metallic activated materials in soil remediation; (iii) Coupling different soil remediation technologies with persulfate; (iv) Preparating persulfate sustained-release materials for soil remediation. This work provides a reference for those who are concerned about the field of remediation of organic pollution in soil by persulfate. [ABSTRACT FROM AUTHOR]

Microbially induced carbonate precipitation (MICP) provides a novel idea to solve the problem of reduction and stabilization of Cr(VI) in contaminated soil. In this study, the remediation of Cr(VI) in severely polluted soil (total Cr = 5530.00 ± 120.21 mg/kg) by MICP technology combined with the Cr(VI)-reducing bacterium Sporosarcina saromensis W5 was systematically investigated. The results indicated that in W5 and CaCl2 treatment after 35 d of remediation, the Cr in exchangeable fraction could be converted into the oxidizable fraction (F3) and the proportion was 41.49%. Compared to original Cr(VI)-contaminated soil, the content of organic matter and soil urease were enhanced after remediation, indicating the improvement of soil quality. The increase in pH also facilitated the formation and stabilization of carbonate precipitation. In addition, the characterization results showed that Cr(VI) in soil was first reduced to Cr(III), and then formed Ca10Cr6O24(CO3) coprecipitation with CaCO3. The stabilization mechanism of Cr(VI) contained bioreduction, adsorption/complexation, and coprecipitation. The results of this study proposed an efficient and reliable strategy of Cr(VI)-reducing bacterium combined with MICP technology to reduce and stabilize Cr(VI) in high concentration Cr(VI) contaminated soil. [ABSTRACT FROM AUTHOR]

Introduction: Soil contamination with copper (Cu) threatens ecological security and human health. Rapeseed demonstrates potential in remediating copper-contaminated soil, and biochar-assisted phytoremediation is increasingly being employed to improve remediation efficiency. However, the combined application of them has not been thoroughly studied in terms of the synergistic effects and the mechanisms of their interaction. Methods: In this regard, this study conducted a pot experiment to evaluate biochar-assisted remediation under Cu-contaminated soil with varying biochar application rates; Furthermore, the plant physiological mechanism and soil physicochemical properties involved in the biocharrapeseed system was explored. Results: Our results showed that the exchangeable pool of copper in soil decreased by 10.0% and 12.3% with adding 5% biochar (BC1) and 10% biochar (BC2) relative to control (BC0), respectively, prior to rapeseed cultivation. The rapeseed cultivation for one season further reclaimed 4.9%, 9.0%, and 13.6% of the available copper in this soil by root extraction under the BC0, BC1, and BC2 treatments, respectively. The overall copper concentration in plants decreased by 23.7% under BC2 and 13.3% under BC1 compared to BC0. However, the plant’s dry biomass at BC1 and BC2 treatments increased by 1.7-fold and 2.7-fold relative to BC0, which offset the negative impact of the decreased copper concentration on phytoremediation. Physiological analysis showed adding 10% biochar decreased the MDA content by 36% in the leaf and 49% in the root, compared to BC0. The transmission electron microscopy for cell wall ultrastructure in root tips showed that biochar addition in Cu-contaminated soil increased the mechanical strength of the celL wall, explicitly increasing the thickness of the secondary cell wall. Further cell wall components analysis revealed a remarkable increment of the pectin content in BC2 relative to BC0, increased by 56% in the leaf and 99% in the root, respectively. Additionally, 10% biochar application led to a roughly 2-fold increase in seed yield via ameliorating the soil physicochemical properties and increasing the rapeseed growth. Discussion: These findings offer insights into synergistic rapeseed-biochar use for Cu-contaminated soil remediation. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) contamination of soil threatens human health, food security, and ecosystem sustainability. The in situ stabilization of Cd has been recognized as a potentially economical technology for the remediation of Cd-contaminated soil. Recently, biochar (BC) and activated carbon (AC) have received widespread attention as eco-friendly soil amendments that are more beneficial for plant growth, soil health, and remediation of contaminated soil. An experiment was performed in a paddy field to investigate the effects of two different types of BC (maize straw biochar and bamboo biochar) and AC (coconut shell activated carbon) in combination with rape organic fertilizer (R), calcium magnesium phosphate fertilizer (P), and fulvic acid (F), respectively, on soil Cd immobilization, Cd accumulation in rice, and yield. The results indicated that the BC/AC-based amendments reduced soil bioavailable Cd (DTPA-Cd) and brown rice Cd by 9.58%--27.06% and 19.30%--71.77%, respectively. The transformation of exchangeable Cd (Ex-Cd) to carbonate-bound Cd (Ca-Cd), Fe-Mn oxide bond (Ox-Cd), and residual (Re-Cd) in soil accounted for the mitigation of Cd uptake and enrichment by rice. Additionally, BC-/AC-based amendments altered soil physicochemical properties, which significantly increased the soil pH and cation exchange capacity (CEC), total nitrogen (TN), total phosphorus (TP), soil organic carbon (SOC), and dissolved organic carbon (DOC), directly promoting soil health. All BC-/AC-based amendments significantly increased FeIMP and MnIMP concentrations by 47.31%--160.34% and 25.72%--73.09% in the Fe/Mn plaque (IMP), respectively. Maize straw and bamboo biochar-based amendments significantly increased rice yield by 10.46%--20.41% and 9.94%--16.17%, respectively, while coconut shell-activated carbon severely reduced rice yield by 65.06%--77.14%. The correlation analysis revealed that leaf Cd and IMP primarily controlled Cd uptake by rice, and soil pH, Eh, CEC, SOC, IMP, and TP influenced DTPA-Cd in soil. This field study demonstrated that maize straw and bamboo biochar-based amendments not only reduced soil DTPA-Cd in paddy fields but also decreased the accumulation of Cd in brown rice, as well as improved rice yield, which has potential application in Cd-contaminated agriculture fields. Coconut shell-activated carbon severely decreased rice yields, which is not appropriate for rice production. [ABSTRACT FROM AUTHOR]

Soil electrokinetics (SEK) research has been widely used in various fields such as soil remediation, dewatering, land restoration, geophysics, sedimentation, pollution prevention, consolidation, and seed germination. According to our most recent published research on SEK process design modifications during the last 30 years (1993–2022), more than 150 designs have been introduced to assure SEK's maximum performance. Incorporating lateral electrodes/anodes was not documented in the existing literature, which motivated us to investigate the output of this design. In this study, we aimed to enhance the performance of the perforated cathode pipe soil electrokinetic remediation (SEKR) system (PCPSS) for removing inorganic pollutants by installing lateral anodes (LA-PCPSS) using two approaches. In the first approach, the LA-PCPSS was connected to different sources of applied voltages (DSAV) from different power supplies, while in the second approach, the entire operation system was connected to the same source of applied voltage (SSAV). We used the Taguchi approach (L9OA) to determine the optimal levels of applied voltages for the DSAV system. The results indicated that the DSAV-(LA-PCPSS) could be optimized at an applied voltage of 1 V cm−1 for the surface and the first and second lateral anodes. The indigenous Sr (elements found in the tested soil without artificial pollution) in kaolinite showed the best response among other elements (Ni and other indigenous elements) when optimizing the DSAV-(LA-PCPSS) using the Taguchi approach. Installing lateral anodes (position B) supplied to low applied voltage (0.5 V cm−1) improved the electroosmosis (EO) rate/dewatering. Reverse migration of ions was observed during the remediation of real contaminated soil using the SSAV-(LA-PCPSS). The DSAV-(LA-PCPSS) is considered an appropriate design for the SEKR of inorganic pollutants, and increases the EO flow/dewatering. Additionally, the increased energy consumption employing the DSAV-(LA-PCPSS) was extremely minimal compared to the traditional PCPSS, which is an economic advantage for SEKR research. The DSAV-(LA-PCPSS) is still under optimization/intensification process, and subsequent processes will be examined to achieve high efficiency. [ABSTRACT FROM AUTHOR]

Limited research has been dedicated to exploring the potential reuse and creation of value‐added products from corn stover. Existing gaps in current research underscore the need for waste biorefineries that adhere to the principles of a circular bioeconomy to maximize the value of corn stover. This review uses bibliometric analysis from the past decade to examine the potential and pathways for converting corn stover into energy and value‐added products within the biorefinery framework. The data were processed using the Web of Science® database and analyzed with the VosViewer® bibliometric software's, Bibliometrix package in R and Gephi, generating keyword‐based maps. A total of 2557 experimental articles and 30 reviews on corn stover research were analyzed. The bibliometric study revealed that the primary research focuses on pretreatment technologies for converting corn stover into value‐added products, bioenergy and biofuels. The main technologies employed include acid, alkaline and enzymatic hydrolysis, as well as torrefaction anaerobic digestion and steam explosion. The pretreatment processes yield sugars, xylooligosaccharides and organic acids. Additionally, the studies explored the use of corn stover biochar for soil remediation and adsorption processes. This review aims to enhance the understanding of technological pathways explored in previous research, contributing to the evaluation of sustainable processes for utilizing corn stover byproducts. Ultimately, it promotes environmentally conscious agroindustry practices that align with circular economy principles and sustainable development. [ABSTRACT FROM AUTHOR]

Background: Phytoremediation is affected by physical and chemical properties of the soil such as soil pH, moisture, and nutrient content. Soil pH is a key element influencing Cd bioavailability and can be easily adjusted in agricultural practices. The soil pH level may relate to the effectiveness of phytoremediation; however, this has not been extensively investigated. In the current study, we evaluated the effect of Cd contamination level (0.56 and 0.92 mg/kg) and soil pH (5, 6, and 7) on Cd accumulation and allocation in Artemisia argyi, a fast-growing perennial crop. Results: Our results indicated that higher soil Cd concentrations reduce A. argyi biomass, and the loss of the root mass was particularly significant. Higher soil pH decreased Cd content in stems and roots of A. argyi cultivated in moderately Cd-polluted soil, and increased Cd content in stems and roots of the plant grown in low Cd-polluted soil. Higher soil pH decreased the percentage of Cd distributed in the soluble fraction and cell walls and increased the percentage of Cd in the organelles of leaf cells for moderate soil Cd levels. The bioconcentration and translocation factor exceeded 4.0 and 1.0, respectively, across all tested treatments, indicating that A. argyi is a promising candidate for phytoremediation. Notably, the effects of soil pH on Cd accumulation and subcellular distribution in A. argyi differed between low and moderately Cd-contaminated soils. Conclusion: Adjustments to soil pH based on the degree of Cd contamination can enhance Cd extraction by A. argyi, thereby reducing the overall remediation cycle of cadmium-polluted paddy fields of South China. [ABSTRACT FROM AUTHOR]

Contemporary issues of ground contamination, exacerbated by elevated heavy metal levels due to industrial activities and improper waste disposal, significantly impact soil properties, the biosphere, and result in various geotechnical problems. This study delves into the efficacy of Chrysopogon zizanioides (vetiver) root micro powder (VRMP) in immobilizing Lead (Pb), Cadmium (Cd), and Chromium (Cr) within contaminated soil to prevent groundwater pollution and bioavailability. Leaching experiments were conducted to evaluate the individual immobilization of heavy metals and determine the optimal VRMP dosage, testing four dosages (0%, 1%, 5%, and 10%) for their effectiveness in immobilizing Pb, Cd, and Cr in contaminated soil. The findings suggest that addition of VRMP led to an increase in pH, facilitating the enhanced immobilization of Pb, Cd, and Cr from the contaminated soil due to the reduction in mobility of these metals. Soil treated with 10% VRMP exhibited exceptional immobilization efficiency, achieving over 90% removal across all treatments. However, agglomeration caused the leaching process to take slightly longer. Consequently, a 5% VRMP dosage is considered optimal. In conclusion, vetiver root micro powder promotes a sustainable approach to immobilize Pb, Cd, and Cr in contaminated soils, underscoring the effectiveness of eco-friendly methodologies. [ABSTRACT FROM AUTHOR]

This study investigated the structural and environmental recovery of weathered hydrocarbon-contaminated soils using low-carbon solutions and aimed to ascertain the suitability of the remediated soils for engineering purposes. 25% (w/w) of ground ripe (RPP) and unripe (UPP) waste plantain peels were each added to 1 kg weathered hydrocarbon-contaminated soil samples and monitored for 90 days. Biological, physicochemical, and engineering properties were analysed for all samples in triplicates. After 90 days of remediation, RPP and UPP nutrients degraded the mid-distillate hydrocarbon alkanes by 93% and 88%, while the heavier hydrocarbon alkanes were degraded by 83% and 85%, respectively. The polyaromatic hydrocarbons (PAHs) had 89% and 93% degradation for RPP and UPP-treated soils, respectively, while the natural attenuation sample had 28% degradation. The soil compressive strength increased by 16% and 19% for RPP and UPP-treated soils, respectively, whereas the natural attenuation soil compressive strength remained fairly constant. It was observed that the remediated soil cohesion, angles of internal friction, maximum dry density, and optimum moisture content all improved as the remediation proceeded, which subsequently showed that the remediation influenced the engineering properties of the contaminated soils. Therefore, the remediation of the contaminated soil improved the structural suitability of the soils. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) toxicity significantly threatens agricultural productivity and food safety. Developing effective strategies to enhance plant tolerance to Cd stress is essential. This study investigates the synergistic effects of biochar (BC) and gibberellic acid (GA3) on mitigating Cd toxicity in maize (Zea mays), focusing on their impact on oxidative stress markers and antioxidant enzyme activities. Soil samples were collected from the Cholistan Institute of Desert Studies (CIDS) and analyzed for trace metal ions and other properties. Biochar was produced from fruit and vegetable waste, washed, washed, deashed, and mixed with 10 ppm GA3. FH-1036 hybrid maize seeds were sterilized and planted in pots containing soil with varying Cd levels (0, 8, and 16 mg Cd/kg soil). Twelve treatments were established, including control, GA3, BC, and their combinations under different Cd stress levels. Plants were irrigated to maintain 60% field capacity and harvested at the V10 growth stage. Hydrogen peroxide (H2O2) contents and activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) were measured in roots, stems, and leaves. Statistical analysis was performed using OriginPro 2021, with ANOVA and Fisher’s LSD test used to determine significant differences. GA3 and BC treatments significantly reduced H2O2 levels in maize roots, stems and leaves under Cd stress. The combined treatment of GA3 + BC showed the most significant reduction in H2O2 levels across all plant parts, reducing root H2O2 by 50%, stem H2O2 by 55%, and leaf H2O2 by 53% under severe Cd stress (16 mg Cd/kg). SOD activity increased under non-stress conditions but decreased under Cd stress, with the highest activity observed in the combined treatment. POD activity followed a similar pattern, with GA3 + BC treatment resulting in the most significant increases under non-stress conditions and the least reductions under Cd stress. CAT activity showed substantial increases with GA3 + BC treatment, particularly under severe Cd stress, with a notable rise over the control. APX activity also exhibited enhancements with GA3 and BC treatments, especially in the combined treatment under various Cd stress levels. This study highlights the potential of combined BC and GA3 treatments in improving Cd stress tolerance in maize. Future research should focus on field trials and the long-term impacts of these treatments on crop productivity and soil health. [ABSTRACT FROM AUTHOR]

Mass transport in frozen ground is typically regarded slow. However, a highly permeable path can exist in frozen saline sand if the unfrozen water is interconnected at the pore scale. We therefore should consider when the unfrozen water is connected and how permeable can frozen saline sand be, yet there are few studies. This research utilizes in‐situ X‐ray CT to evaluate unfrozen water connectivity and permeability in frozen saline sand considering effects of initial salt content, temperature, freezing rate, and temperature gradient. Results show that higher initial salt content and/or temperature, both of which results in a higher unfrozen water content, easily maintains unfrozen water connectivity. Rapid freezing minimizes the brine expulsion and permits a higher unfrozen water content hence better connectivity. Permeability in frozen saline sand can be several orders higher than the typically reported value, highlighting the potential presence of rapid mass transport through the connected unfrozen water. Plain Language Summary: Frozen aqueous sandy soils in nature often contain a lot of substances such as dissolved salts, gases, contaminants. Mass migration via unfrozen water is of vital importance to groundwater flow, greenhouse gas emission, even contaminated soil remediation. Permeability determination of unfrozen water is well‐studied in salt‐free soils. Our study shows there can be a highly conductive path in frozen saline sand when the unfrozen water is interconnected, even at a low unfrozen water saturation of 14%. The connectivity of unfrozen water remains at −20°C with an initial salt concentration similar to seawater. Rapid freezing causes better connectivity because less unfrozen water is squeezed out of the frozen sand during ice growth. Permeability in frozen saline sand can be several orders of magnitude higher than the typically reported value. These findings indicate that mass transport in frozen ground, via the connected unfrozen water, can be much more active than previously thought. Key Points: Pore‐scale unfrozen water can be interconnected, enabling fast mass transport below 0°C when soil contains saltRapid freezing enhances unfrozen water connectivity and permeability due to less and slower salt migration during freezingPermeability of frozen saline sand can be several orders of magnitude higher than that of salt‐free soil [ABSTRACT FROM AUTHOR]

Hexavalent chromium (Cr(VI)) pollution poses significant health and ecological risks warranting cost-effective remediation. This study investigated the efficacy of zinc oxide nanoparticles (nZnO) and Miscanthus lutarioriparius synergism for Cr(VI) immobilization and stabilization. nZnO characterized by XRD, SEM-EDS and DLS was amended to 3 mg kg−1 Cr(VI) spiked soil pots at 0.5 % and 1 %. M. lutarioriparius seedlings were then transplanted and grown for 3 months. Results showed increase in residual soil Cr(III) from negligible to 68.9 % upon 1 % nZnO indicating reduction of Cr(VI). Maximum decline of 76.3 % in total Cr(VI) confirmed immobilization. Batch adsorption experiments revealed rising Cr(VI) removal from 61.3 % to 83.7 % by increase in nZnO dose from 0.2 to 1 g L−1. M. lutarioriparius demonstrated hyperaccumulator ability uptaking 208.3 and 156.8 mg kg−1 Cr in roots and shoots respectively. Restricted root-shoot translocation factor of 0.79 aided suitability for phytostabilization. The plant-nZnO synergy enhanced remediation efficiency as confirmed by tolerance index restoration from 38.6 % to 100 %. Increased growth performance reflected mitigation of toxicity by restricted bioavailability. Overall, the nanoremediation strategy displayed high potential for effective in situ stabilization of Cr(VI) contamination combining favorable properties of nZnO and plant tolerance mechanisms. [ABSTRACT FROM AUTHOR]

The persistent and hazardous nature of polycyclic aromatic hydrocarbons (PAHs) released into the soil has become a critical global concern, contributing to environmental pollution. In this study, the removal efficiency of phenanthrene and naphthalene degradation by complex flora or pure bacteria combined with corn and their effects on the growth of corn, pH, and the number of soil bacteria were investigated using a pot experiment. The results indicate that the corn remediation method (P) outperformed degrading bacteria remediation (B) for phenanthrene, yet the combination (PB) exhibited significantly higher removal efficiency. The degradation efficiency of PB methods increased over time, ranging from 58.40% to 75.13% after 30 days. Naphthalene removal showed a similar trend. Soil pH, influenced by remediation methods, experienced slight but non-significant increases. The number of degrading bacteria increased with combined methods, notably with PB-W1 and PB-W2 treatments. Corn accumulated phenanthrene and naphthalene, with higher concentrations in roots. Remediation by the combined corn and degrading bacteria slightly increased PAH accumulation, indicating potential root protection. Biomass yield analysis revealed the inhibitory effects of PAHs on corn growth, decreased by degrading bacteria. PB-W1 and PB-EF3 demonstrated the highest fresh weight and moisture content for stem and leaf biomass, while PB-F2-6 excelled in root biomass. Overall, combined remediation methods proved more effective, which underscores the potential of the corn and degrading bacteria consortium for efficient PAH remediation in contaminated soil. [ABSTRACT FROM AUTHOR]

The consequences of climate change urgently demand the reduction of atmospheric carbon, including by sequestering carbon in soil. The glomalinrelated soil proteins (GRSP) of arbuscular mycorrhizal fungi (AMF) are renowned for their soil aggregation and carbon sequestration properties. With their considerable binding abilities, GRSP can also adsorb various cations and sequester heavy metals in soil, thereby assisting in soil fertilization and remediation efforts. However, despite its benefits for soil health and climate change, the mechanisms underlying these traits in the context of soil chemistry remain unexplored. In this review, we focus on three crucial roles of GRSP--long-term carbon sequestration, soil aggregation, and soil remediation and fertility--in the context of the chemical characteristics elucidated by previous research, namely hydrophobicity, amid group glycosylation (N-glycosylation), and metal adsorption. Based on the proposed chemical mechanisms, the current review also offers insight into soil factors that may influence the persistence of GRSP. We conclude by proposing a working model for GRSP, aiming to establish a conceptual platform for future research to examine GRSP in terms of their known or novel chemical and biochemical reactions, thereby improving our understanding of this important group of soil proteins. [ABSTRACT FROM AUTHOR]

Soil pollution by heavy metals (HMs) is a major environmental problem around the world. The addition of biowaste-based stabilizers for HM remediation has recently gained attention due to its relatively low cost and eco-risk, abundance, ease of operation, and quick remediation results. Among these stabilizers, shell (crustacean shell, bivalve shell, and eggshell), starfish, and bone-based stabilizers are particularly attractive because of their high Ca and P contents, allowing for highly efficient HM immobilization and simultaneous supplement of nutrients to the soil. However, a comprehensive review focusing on these stabilizers is currently missing. Therefore, this review attempts to summarize the HM immobilization efficiency of these stabilizers and the mechanisms associated with HM stabilization, and perform an operation cost estimation and cost comparison. Cost comparisons among different stabilizers are widely ignored in reviews due to the lack of reliable cost estimation tools or methods. However, for practical application in soil remediation, cost is one of the most important factors to consider. Thus, a simple but reasonable cost estimation method is developed and discussed in this review. Bivalve shell-based stabilizers demonstrated the most promising results for the immobilization of soil HMs in terms of higher performance and lower cost. Current research limitations, challenges, and recommendations regarding possible future research directions are also provided. [ABSTRACT FROM AUTHOR]

The engineering of biochars with desired morphologies and pore structures is a far-reaching objective towards sustainable pore-dependent environmental technologies, such as water and soil remediation or catalysis. We hereby report a series of experiments that allow the direct following of the shape and porosity of single biochar particles during pyrolysis. Particles ~ 1–2 mm in diameter of unwashed and water-washed raw walnut shells were continuously 3D imaged during pyrolysis to 575 ℃ at a 10 K min−1 in Ar to obtain time- and temperature-resolved x-ray micro computed tomographies to a 0.82 μm resolution. Results showed visual evidence of a 30% and 70% v/v particle shrinkage for unwashed and washed samples, respectively. Particle swelling between 200 and 300 ℃ in the unwashed sample provided evidence of the softening of native biopolymers associated with lignin in untreated biomass. A purpose-defined parameter Λ shows the temperature-dependence of pore re-distribution towards the center of the particle to be linear for both samples. Λ was found to be 3.2 × 10 - 4 K - 1 in the washed sample, approximately 3.5 times faster than in the unwashed one. Such linear dependence is significantly slower than an exponential Arrhenius-like trend thereby providing a qualitative measure of the heat and mass transport phenomena limiting the chemical reactions in the porous medium. This evidence is key to resolving the pathways to the thermochemical decomposition of biomass leading to preparation of precision-engineered biochars. Highlights: Evolution of morphology of single particle (1–2 mm) walnut shell was tracked in operando during pyrolysis via micro-CT (~ 812 nm resolution). Samples pre-washed in water didn't exhibit particle swelling observed in untreated samples in the 200–300 ℃ range. Porosity towards the center of the particle was developed 3.5 faster in washed samples than in unwashed ones. [ABSTRACT FROM AUTHOR]

The effect of trivalent metal-modified biochar on the stability and mitigation of fluoride ions (F-) in contaminated soils remains largely unexplored, despite biochar's extensive application in F--contaminated soil. The mineral metal-modified biochar has the potential to serve as an efficient solution for soil contaminated with F-. In this study, pristine-pinecone biochar (P-BC) and AlCl3-modified pinecone biochar (A-BC) were synthesized and then utilized to remediate the soil that had been contaminated with F-. Both P-BC and A-BC efficiently immobilized F- within the contaminated soil. Further examinations through sequential extraction procedure and subsequent analysis using scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and elemental dot mapping demonstrated a transformation of F- into a more stable state by A-BC treatment of the contaminated soil. This implies that A-BC may possess the capacity to function as an efficient ameliorant for immobilizing F- within the soil. [ABSTRACT FROM AUTHOR]

The persistent reliance on coal has resulted in the accumulation of substantial coal gangue, a globally recognized problematic solid waste with environmental risks. Given the coal gangue properties and global land degradation severity, the resourceful utilization of coal gangue as soil conditioners is believed to be a universally applicable, cost-effective, high-demand and environment-friendly model with broad application prospect. The direct application of raw coal gangue faces challenges of low active beneficial ingredients, inadequate water and fertilizer retention, presence of potentially toxic elements, resulting in limited efficacy and environmental contamination. This paper provided a comprehensive review of various modification methods (including mechanical, chemical, microbiological, thermal, hydrothermal and composite modifications) employed to enhance the soil improvement performance and reduce the environmental pollution of coal gangue. Furthermore, an analysis was conducted on the potential application of modified coal gangue as a muti-function soil conditioner based on its altered properties. The modified coal gangue is anticipated to effectively enhance soil quality, exhibiting significant potential in mitigating carbon emissions and facilitating soil carbon sequestration. This paper provided innovative ideas for future research on the comprehensive treatment of coal gangue and restoration of degraded soil in order to achieve the dual goals of zero-coal gangue waste and sustainable agriculture. [ABSTRACT FROM AUTHOR]

In order to identify the factors causing environmental pollution caused by petroleum industries in Ahvaz County, Khuzestan province, regarding local concerns, the area of soil affected by the operational activity of crude oil desalting plantation (CODP) should be determined. In addition, in order to identify obvious environmental risks leading to soil pollution, it is necessary to identify hazardous activities ‎(HA). MCDM methods, or multi-criteria decision-making models, for ranking options, and choosing the best option for identifying environmental risks. Therefore, in this research, by examining models of multi-criteria decision-making, including the AHP Analytical Hierarchy Process and the TOPSIS Model (Technique for Order of Preference by Similarity to Ideal Solution), HAs for determining the possibilities of contamination have been discussed. HAs are considered to determine the possibility of contamination. According to the results, the transfer of saline oil from the exploitation unit to the CODP, with a specific ‎vector weight of 0.214 in the AHP method and a proximity coefficient of 0.445 in the ‎TOPSIS method, gain highest rank in terms of HAs in the study area. Regarding the risk assessment and assurance of the creation of salinity and sometimes petroleum pollutants in the region, and also the local obligations and regulations of the founders, industrial devices should preferably use biological methods to remediate and naturalize the environment. According to the results, and regarding the fact that halophyte can grow and develop well in the saline conditions; halophyte culture (haloculture technique) can be used as a method for soil bioremediation. [ABSTRACT FROM AUTHOR]

Reductive dissolution of barium (Ba) sulfate in wetland soils may increase Ba bioavailability in the environment, yet no information is available regarding Ba remediation using biochar. This study investigated the effectiveness of sugarcane (Saccharum officinarum) straw biochar pyrolyzed at 350 °C (BC350), 550 °C (BC550), and 750 °C (BC750) in inhibiting barite dissolution and, consequently, Ba availability in a soil artificially spiked with barite and flooded for 365 days. Increasing pyrolysis temperature alters the carbon structure, and increases dehydration and depolymerization, resulting in more stable biochar that releases less DOC (8.6-fold decrease from BC350 to BC750). Additionally, high-temperature biochar (BC750) had 1.7 times higher carbon (C) content, 2.4 times higher ash content, and a 13.1 times greater specific surface area (SSA) than low-temperature biochar (BC350). Amending soil with BC750 increased pH but did not promote reducing conditions, and thus did not promote barite dissolution. Conversely, greater DOC in low-temperature biochar, particularly BC350, favored reducing conditions and increased barite dissolution by 23%, with BC550 also showing an 18% increase. This enhancement led to a greater pool of Ba sorbed into more labile exchangeable sites. In summary, pyrolysis temperature affects biochar attributes, which in turn influences the soil geochemical environment and Ba speciation. Low-temperature biochar (BC350) shows potential as an amendment to increase the bioavailable Ba pool in assisted remediation programs, such as biochar-assisted phytoremediation. Highlights: • Biochar pyrolysis temperature affected both redox potential and barite dissolution. • BC750 mitigated barite dissolution while modifying exchangeable sorption sites. • DOC release from low temperature biochar promoted barite reductive dissolution. • BC350 may enhance biochar-mediated phytoremediation applications. [ABSTRACT FROM AUTHOR]

High lead (Pb) levels in agricultural soil and wastewater threaten ecosystems and organism health. Microbial remediation is a cost-effective, efficient, and eco-friendly alternative to traditional physical or chemical methods for Pb remediation. Previous research indicates that micro-organisms employ various strategies to combat Pb pollution, including biosorption, bioprecipitation, biomineralization, and bioaccumulation. This study delves into recent advancements in Pb-remediation techniques utilizing bacteria, fungi, and microalgae, elucidating their detoxification pathways and the factors that influence Pb removal through specific case studies. It investigates how bacteria immobilize Pb by generating nanoparticles that convert dissolved lead (Pb-II) into less harmful forms to mitigate its adverse impacts. Furthermore, the current review explores the molecular-level mechanisms and genetic engineering techniques through which microbes develop resistance to Pb. We outline the challenges and potential avenues for research in microbial remediation of Pbpolluted habitats, exploring the interplay between Pb and micro-organisms and their potential in Pb removal. [ABSTRACT FROM AUTHOR]

The contamination of soil with the heavy metal cadmium (Cd) is increasingly prominent and severely threatens food security in China. Owing to its low cost, suitable efficacy, and ability to address the shortcomings of plant remediation by enhancing the ability of plants to take up Cd, plant–microbe combination remediation technology has become a research hotspot in heavy metal pollution remediation. A pot experiment was performed to examine the effects of inoculation with the plant-growth-promoting bacterium Brevibacillus sp. SR-9 on the biomass, Cd accumulation, and soil nutrients of hybrid Pennisetum. The purpose of this study was to determine how Brevibacillus sp. SR-9 alleviates stress caused by heavy metal contamination. High-throughput sequencing and metabolomics were used to determine the effects of inoculation on the soil bacterial community composition and microbial metabolic functions associated with hybrid Pennisetum. The results suggest that mutation of Brevibacillus sp. SR-9 effectively alleviates Cd pollution stress, leading to increased biomass and accumulation of Cd in hybrid Pennisetum. The aboveground biomass and the root weight increased by 12.08% and 27.03%, respectively. Additionally, the accumulation of Cd in the aboveground sections and roots increased by 21.16% and 15.50%, respectively. Measurements of the physicochemical properties of the soil revealed that the strain Brevibacillus sp. SR-9 slightly increased the levels of available phosphorus, total nitrogen, total phosphorus, and available potassium. High-throughput DNA sequencing revealed that Brevibacillus sp. SR-9 implantation modified the composition of the soil bacterial community by increasing the average number of Actinobacteria and Bacillus. The total nitrogen content of the soil was positively correlated with the Actinobacteria abundance, total phosphorus level, and available phosphorus level. Metabolomic analysis revealed that inoculation affected the abundance of soil metabolites, and 59 differentially abundant metabolites were identified (p < 0.05). Among these, 14 metabolites presented increased abundance, whereas 45 metabolites presented decreased abundance. Fourteen metabolic pathways were enriched in these metabolites: the folate resistance pathway, the ABC transporter pathway, D-glutamine and D-glutamic acid metabolism, purine metabolism, and pyrimidine metabolism. The abundance of the metabolites was positively correlated with the levels of available phosphorus, total potassium, total phosphorus, and total nitrogen. According to correlation analyses, the development of hybrid Pennisetum and the accumulation of Cd are strongly associated with differentially abundant metabolites, which also impact the abundance of certain bacterial populations. This work revealed that by altering the makeup of microbial communities and their metabolic processes, bacteria that promote plant development can mitigate the stress caused by Cd. These findings reveal the microbiological mechanisms through which these bacteria increase the ability of hybrid Pennisetum to take up the Cd present in contaminated soils. [ABSTRACT FROM AUTHOR]

The exogenous application of oxalic acid is a potential approach to amplifying phytoremediation performance on Cd-contaminated soils. However, few studies explore the optimal oxalic acid application regime from a perspective of coupling different concentrations and timings to maximize Cd removal rate. Given this, a pot experiment was conducted using oil sunflower (Helianthus annuus L.) as the test plant. Oxalic acid was added to the pots at concentrations of 1, 2, 3, 4, 5, and 6 mmol/kg at 20, 30, 40, and 50 days after emergence. A control (CK) without exogenous oxalic acid was also included. We examined the discrepancies in various soil Cd forms, sunflower height, plant non-protein thiol (NPT) levels, and soil Cd remediation efficiency under different oxalic acid application regimes. The results showed that applying oxalic acid at a concentration of 4 mmol/kg reduced the proportion of Fe-Mn oxide Cd and organic Cd compared to the control (CK), while increased the proportion of available Cd. The optimal application time is 30 or 40 days after emergence. The addition of exogenous oxalic acid promoted the growth of sunflowers, with the greatest increase in plant height observed when 4 mmol/kg oxalic acid was applied at 30 days after emergence. Exogenous oxalic acid enhanced the absorption of Cd by sunflower roots, with the total Cd accumulation in roots, stems, and leaves being higher than in the control (CK). When 4 mmol/kg oxalic acid was applied at 30 days after emergence, the total Cd accumulation in roots, stems, and leaves was highest. Under different application times and concentration levels of oxalic acid, Cd accumulation was highest in roots, followed by leaves, with stems showing the lowest accumulation. The NPT content in each part is as follows: root > stem > leaf. Applying 5 mmol/kg oxalic acid after 30 days of sunflower emergence resulted in relatively higher total NPT content in roots, stems, and leaves compared to the control (CK). The TOPSIS model was used for comprehensive evaluation, which showed that 4 mmol/kg oxalic acid application at 30 days after emergence could be used as the optimal oxalic acid application regime for phytoremediation. These findings indicate that the addition of oxalic acid effectively promoted the absorption of Cd by sunflower and increased the efficiency of Cd removal from the rhizosphere soil, with the optimal removal of soil Cd achieved by applying oxalic acid at a concentration of 4 mmol/kg 30 days after the emergence of oilseed sunflower seedlings. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) contamination in agricultural soils is a common issue, posing health risks as it enters the human body through the food chain. Commonly used phosphate fertilizers (PFs) not only provide essential phosphorus (P) nutrients to crops but also serve as P-containing materials for immobilizing heavy metals (HMs) like Cd in soils. Therefore, understanding the passivation effects of PFs on soil Cd and their potential influencing factors is crucial for mitigating soil Cd pollution. In this study, the impact of multi-crop applications (75 mg P kg−1, 150 mg P kg−1) of four kinds of PFs on reducing soil Cd toxicity and decreasing Cd accumulation in spinach was investigated. The results indicated that under the low application rate (75.0 mg P kg−1), all PFs could passivate Cd, and CMP demonstrated the most effective passivation of Cd. However, under the high application rate (150 mg P kg−1), the immobilization effect diminished or even activated Cd. Among the different types of PFs, CMP application alleviated soil acidification and significantly reduced soil-available Cd, showing the best performance in promoting spinach growth and Cd inhibition. These results suggest that PF application in Cd-contaminated soils affects spinach growth and Cd accumulation, with soil pH, available phosphorus (AP), and Cd dynamics being crucial; moreover, low-P, micronutrient-rich, alkaline PFs like CMP optimize spinach yields and minimize Cd uptake, and excessive application of soluble PFs decreases pH, increases Cd mobility, and poses health risks, suggesting a need for balanced fertilizer use. [ABSTRACT FROM AUTHOR]

To reduce energy consumption and secondary contamination of soil, using natural biosurfactants-tea saponins as enhancement agent was studied on electrokinetic remediation (EKR) of cadmium (Cd)-spiked soil powered by solar energy. The current during EKR, the pH of soil before and after remediation, the initial and the residual Cd in the soil, Cd collected in the electrolyte, the mass balance of Cd, and cost analysis and energy consumption were investigated. Analytical methods such as Fourier Transform Infrared Spectrometer (FTIR), Scanning Electron Microscope (SEM), and Energy Dispersive Spectroscopy (EDS) were applied. Experimental results showed that tea saponins could increase the removal of Cd from the soil by promoting Cd desorption and its complexation that increased its mobility. There was a significant positive correlation between the concentration of tea saponins and Cd removal efficiency, but this positive correlation gradually decreased and the most suitable concentration of tea saponins was 2 g/L under the conditions of this experiment. EKR driven by solar power (Treatment time: 180 h) can achieve the Cd removal efficiency of approximately 90% which was a promising technology for soil remediation, especially in regions with abundant sunshine year-round. FTIR analysis indicates that tea saponins can be quickly and naturally degraded without resulting in secondary pollution to the soil. According to SEM and EDS analysis, most of the Cd pollutants in the soil were removed by EKR, but some pore clogging still existed. [ABSTRACT FROM AUTHOR]

In situ immobilization is a potential approach that can be used to remediate low-to-medium levels of heavy-metal in contaminated-soil. There is little known about how modifications to soil characteristics may affect Pb's release from soil. The four different amendments, triple-superphosphate and attapulgite were combined in Ad-1; zeolite and triple-superphosphate were in Ad-2; hydroxyapatite and humus were in Ad-3; and nano-carbon. These amendments are mostly made of phyllosilicate minerals, humus, base minerals, and nano-carbon, respectively. Results revealed that the test amendments' maximal Pb-adsorption capacity varied from 7.47 to 17.67 mg g−1. Surface precipitation and ion-exchange were found to be the main mechanisms for Pb-adsorption by Ad-1 and Ad-2, while Ad-3 and Ad-4 were promising among the all, according to analysis of the modifications both before and after Pb loading. When the pH dropped (7-1) or the ion-strength rose (0–0.2 M), there was a discernible rise in the Pb-desorption percentages from the amendments. It was determined that Ad-3 and Ad-4 were more effective in situ immobilizing lead in contaminated-soils because of their high adsorption capacities (12.82 and 17.67 mg g−1) and low-desorption percentages (4.46–6.23%) at ion-strengths of 0.01–0.1 mol L−1 and pH levels ranging from 5 to 7. NOVELTY STATEMENT: This study pioneers a comprehensive exploration into the efficacy of novel soil amendments, Ad-3 and Ad-4 crafted from phyllosilicate minerals, humus, base minerals, and nano-carbon, showcasing their unprecedented potential in mitigating lead pollution. By delving into the intricate mechanisms of lead adsorption and desorption within treated soils, this research fills a critical gap in understanding how modifications to soil characteristics can influence the secondary release of lead, thus providing essential insights for tailored in situ remediation strategies to safeguard both plant and human health in lead-endangered environments. [ABSTRACT FROM AUTHOR]

Military sites, both active and decommissioned, are rarely studied and may represent a source of fungal bioresources with potential applications for the remediation of co-contaminated soils. The aims of this study were both deepening the knowledge on fungal communities of a decommissioned military site and identifying indigenous bioresources showing potentialities for downstream mycoremediation applications. The culturable fractions of soil fungal communities of an Italian decommissioned military site were isolated from six representative sampling plots. In addition, the fungal community of the rhizosphere of Plantago lanceolata was also isolated. α and β diversity indices were used to analyze biodiversity data of the isolated fungal communities. A polycyclic aromatic hydrocarbons (PAHs) enrichment microplate experiment in the presence of Zn, Pb, and Zn-Pb co-contamination was conducted, followed by in vitro functional traits screenings, to select the isolates with the best potential for future mycoremediation applications. Globally 101 taxa, accounting for a total of 546 strains, were isolated from the samples. The enrichment results highlighted several fungal species showing the ability to use PAHs as nutritional source, even in the co-presence of potentially toxic elements. Finally, the analysis of their functional traits revealed their potential for biotechnological applications in soil detoxification. [ABSTRACT FROM AUTHOR]