A DFT-explainable machine-learning (DFT-XML) strategy integrated with an active learning mechanism was proposed and validated to connect quantum-level molecular properties with macroscopic environmental behaviors of halogenated polycyclic aromatic hydrocarbons (HPAHs). Density Functional Theory (DFT)-derived quantum descriptors were combined with conventional physicochemical features for 57 representative HPAHs to construct a stacking-ensemble model, HPAHs-SM. Notably, a Query-By-Committee (QBC) strategy was implemented to quantify epistemic uncertainty, transforming the model from a static estimation tool into a dynamic guidance system for experimental design. The model predicted four key endpoints-Log P (octanol-water partition coefficient), Biowin (QSAR-based biodegradability estimate), Log BCF (bioconcentration factor), and Log KOC (organic carbon-water partition coefficient)-with strong test-set performance (R2 values of 0.875, 0.902, 0.842, and 0.909, respectively). Crucially, the framework was anchored in empirical reality through validation against literature-reported environmental half-lives (t1/2), demonstrating robust agreement between predicted degradability trends and physical persistence. the active learning strategy prioritized high-uncertainty targets (e.g., Log BCF standard deviation = 0.705) for validation, effectively bridging the gap between computational modeling and experimental reality. Mechanistic interpretation using SHapley Additive exPlanations (SHAP) and descriptor analysis identified molecular polarizability as the principal determinant of adsorption and migration, while LUMO energy was found to strongly regulate degradability and potential biotoxicity. Compounds were projected into the model's interpretation space and subjected to unsupervised clustering, yielding five risk-based subgroups that improved translation from microscopic descriptors to macroscopic risk assessment; for instance, 6-chloro/6-bromo-benzo[a]pyrene-characterized by high polarizability and large molecular mass-was classified as high risk with a "strong adsorption-low degradation" profile. An open-access web platform (HPAHs-ML) was developed to support molecular input, multi-endpoint prediction, and visualization (https://hpahs-stacking-model.streamlit.app/). The proposed DFT-XML paradigm was demonstrated to provide an interpretable, self-evolving and data-driven route for environmental risk assessment and for guiding the design of lower-risk halogenated contaminants.

Due to their high environmental persistence and bioaccumulation, the degradation mechanisms and elimination pathways of halogenated organic contaminants (HOCs) have become a focal point of research in environmental science. To address challenges such as low experimental throughput, the scarcity of degradation samples, and the limitations of conventional prediction models in handling molecular complexity and highly imbalanced data, we constructed a high-quality benchmark dataset comprising 614 HOC samples (47 readily biodegradable and 567 non-readily biodegradable) and developed a biodegradability prediction platform, HOCs-BDPred, based on a multi-modal Transformer architecture. This platform utilizes a dual-stream parallel Transformer framework to achieve deep synergistic representation of semantic features from SMILES sequences and high-dimensional topological information from molecular fingerprints. To overcome the constraints imposed by small-sample imbalanced data, we introduced SMILES data augmentation techniques and a Focal Loss weighted function, significantly enhancing the model's recognition sensitivity and generalization boundaries for the minority class. Experimental results demonstrated that the model achieved the overall accuracy of 93.48%, the balanced accuracy of 76.99%, and the Matthews correlation coefficient (MCC) of 0.548. Furthermore, an online Web prediction platform (https://hocs-bdpred.streamlit.app/) was developed and deployed for practical validation, providing an intelligent, high-throughput decision-support tool for the rapid screening of HOC biodegradability and the proactive design of green alternative chemicals.

Zirconium-based coagulants are a novel class of inorganic coagulants that have attracted considerable attention in recent years because of their outstanding coagulation performance. This study introduces a novel polymeric zirconium-based coagulant and compares the coagulation performance of two variants with different counterions, polymeric zirconium chloride and polymeric zirconium sulfate, in treating domestic sewage. The results show that both polymeric zirconium sulfate and polymeric zirconium chloride achieve turbidity removal rates above 95%, total organic carbon removal above 90%, and total phosphorus removal above 90%. The flocs exhibit a dense core, a rough surface, good settling properties, and a large specific surface area. These coagulants primarily remove contaminants through the synergistic mechanisms of charge neutralization and adsorption bridging. Compared with polymeric zirconium chloride, polymeric zirconium sulfate exhibits more stable removal efficiency across a broader dosage range and performs better over a wider pH range. Polymeric zirconium chloride derived flocs have a faster grow rate, whereas polymeric zirconium sulfate derived flocs show greater resistance to breakage and stronger recovery capacity. The mechanistic similarities and differences were further elucidated through molecular dynamics simulations. This study provides theoretical support for the application of polymeric zirconium-based coagulants in water treatment.

Stimulus responsive adsorption materials (SRAMs) can realize the controllable reconfiguration of interface properties and adsorption behavior under the external stimulus, and show unique advantages in the treatment of complex environmental pollution. In this paper, the mechanism of SRAMs in environmental remediation and the progress in pollutant treatment are systematically reviewed, with emphasis on the enhancement of structural stability, response sensitivity and adsorption selectivity of materials by synthetic strategies such as chemical coprecipitation and surface imprinting, and the structure-activity relationship and regulation path under the coupling conditions of temperature, pH, light, magnetism and multiple stimuli are deeply analyzed. On this basis, an interpretable machine learning prediction framework for SRAMs rational design is further proposed, which covers the construction of material descriptors, model training of task adaptation, feature contribution analysis and closed-loop verification of experiments, and can effectively extract the relationship of “synthesis conditions-structural features-environmental performance”, thus giving consideration to the efficiency of material screening and the cognitive depth of mechanism. Simultaneously, a standardized evaluation idea suitable for SRAMs is constructed to improve the comparability and consistency of performance characterization and application criteria among different studies. This paper can provide theoretical basis and technical support for the precise screening, performance prediction and standardized application of SRAMs in complex environmental pollution control.

Selecting between axenic strains and microbial consortia remains a key challenge in microbial remediation. Here, we established a systematic quantitative framework to compare their degradation performance and biological traits across six pollutant classes: petroleum hydrocarbons, antibiotics, pesticides, polycyclic aromatic hydrocarbons (PAHs), heavy metals, and plastics, under comparable experimental contexts. For complex substrates requiring sequential transformation and mineralisation, especially petroleum hydrocarbons and PAHs, microbial consortia generally showed higher degradation efficiency through metabolic division of labour, biofilm enrichment, and functional redundancy. Reported efficiency improvements ranged from approximately 17% to 73%, with selected cases reaching up to 200%. In contrast, for certain antibiotics and pesticides, consortium performance was inconsistent and sometimes inferior to acclimated or engineered axenic strains due to interspecific antagonism, metabolic inhibition, or unstable functional coordination. Based on the assembled evidence, we propose a decision-making framework for remediation strategy selection: microbial consortia are preferable for complex, multi-step substrates, whereas axenic strains are more suitable for highly toxic contaminants or scenarios requiring strong operational controllability. This study provides quantitative evidence and practical guidance for rational microbial strategy selection, system design, and scale-up in bioremediation engineering.

This study addresses the decline in biological denitrification performance caused by the respiratory chain inhibition of the arylpyrrole insecticide chlorfenapyr. A nanoscale zero-valent iron (nZVI) enhanced biological aerated filter (BAF) system was constructed to investigate the enhancement efficiency of nZVI and its regulatory mechanisms on the metabolism of denitrifying microorganisms. The results showed that nZVI significantly improved the system's shock load resistance and recovery resilience. Under chlorfenapyr stress, the system maintained a maximum NH4+-N removal rate of 83.86% and TN removal rate of 80.88%. Multi-omics analysis indicated that nZVI promoted the expression of extracellular polymeric substances (EPS) related genes to ensure their secretion and structural stability. This process effectively reduced reactive oxygen species (ROS) levels and achieved 81% biodegradation of chlorfenapyr. nZVI alleviated the impact of chlorfenapyr stress on the dominant phylum Pseudomonadota and simultaneously induced the directional enrichment of Luteimonas and Truepera with tolerance and degradation potential. Analysis of the respiratory chain and nitrogen metabolism pathways revealed that nZVI up-regulated the expression of genes encoding respiratory chain core complexes including Complex I through Complex V. nZVI also mitigated the 10% inhibition of denitrification (NAR) genes caused by chlorfenapyr and promoted the dissimilatory nitrate reduction to ammonium (DNRA) pathway. Metabolic correlation analysis further demonstrated that nZVI induced the directional enrichment of the key functional genus Luteimonas and driven its secretion of Lpc (18:1) and Lpc (19:1-Sn1) to strengthen biofilm repair. This work provides theoretical support for the efficient and stable operation of high-toxicity and high NH4+-N wastewater treatment.

Chlorfenapyr, a novel pyrrole insecticide, had not been systematically characterized with respect to its microecological effects and metabolic mechanisms in soil. In this study, high-throughput sequencing and untargeted metabolomics were combined under varied redox conditions to quantify the coupled effects of chlorfenapyr exposure on soil microbial community structure, functional reassembly, and metabolic responses. Chlorfenapyr concentration and redox properties jointly drove community succession in a dose-dependent manner. At low concentrations, community stability was maintained through functional redundancy, whereas high-concentration stress triggered disruptive reassembly and selection of tolerant or degradative taxa. Under aerobic conditions, MM2 became dominant at high concentrations (28.12% at 1.0 mg/g, stabilizing at similar to 22%), and Sphingomonas abundance increased at low concentrations. Under anaerobic conditions, Desulfosporosinus was significantly enriched at high concentrations (1.5-2.0 mg/g). Spatial analysis revealed reduced diversity near contamination sources with recovery at distance, while temporal dynamics confirmed that redox potential governed successional trajectories, with oxic conditions enriching Sphingomonas and Nocardioides for cooperative degradation and anoxic conditions maintaining stable communities dominated by Methylotenera. Metabolic evidence showed upregulation of the shikimate pathway and ABC transport systems, with multi-stage degradation routes supporting chlorfenapyr mineralization. Correlation analysis revealed that shikimate-pathway metabolites were significantly associated with Sphingomonas, and Desulfosporosinus was linked to phenylalanine metabolites and reductive dehalogenation products, supporting functional differentiation between aerobic and anaerobic pathways. The concentration-redox interaction governing community assembly and functional reorganization was thus elucidated, providing a multi-layer evidence chain to inform precision bioremediation strategies and candidate biomarkers for complex polluted soils.

Vegetation cover effectively reduces uncontrolled landfill gas emissions; however, the biotransformation mechanisms underlying different vegetation types remain poorly understood. This study, for the first time, systematically compared the efficiencies and underlying mechanisms of methane (CH4)-chlorobenzene (CB) codegradation under herbaceous (White clover), shrub (Castor plant), and arbor (Broussonetia papyrifera) vegetation covers based on a three-dimensional simulated landfill system integrated with microbial diversity and metabolomic analyses. Castor plant and Broussonetia papyrifera facilitated oxygen transport to establish redoxstratified soil profiles. Castor plant expanded the anoxic zone, which enhanced facultative anaerobic degradation, while Broussonetia papyrifera increased overall aerobic oxidation by extending the aerobic zone. Castor plant and Broussonetia papyrifera enhanced CH4 degradation by 7.41% and 14.43%, and CB removal by 22.17% and 40.67%, respectively, when compared to unvegetated controls. On the other hand, White clover slightly increased CB (4.52%) but decreased CH4 degradation (17.37%). Vegetation significantly reorganized microbiomes and interaction networks. Broussonetia papyrifera enriched Methylobacter, Castor plant favored Pseudoxanthomonas, and White clover selected for low-oxygen-tolerant Chryseolinea; rhizosphere interactions exhibited an 8.05%-17.74% rise in positive associations. According to metabolomic profiling, Broussonetia papyrifera uniquely secreted 8,8-dimethoxy-2,6-dimethyl-2-octanol and 1-(11Z-eicosenoyl)-glycero-3-phosphate, which activate dehalogenases and improve quinone cycling in degraders. This study proposes a Broussonetia papyriferacastor plant composite planting system that reduces landfill greenhouse gas emissions by 38.9%-53%, providing a novel approach to low-carbon landfill management and ecological restoration, guided by the VegetationMicrobe Synergy Model.

Addressing the limitations of existing studies that predominantly isolate Tetrabromobisphenol A (TBBPA)-degrading bacteria from contaminated environments and focus on degradation characteristics, this study employed multi-omics approaches to systematically elucidate the dynamic succession patterns and metabolic adaptation mechanisms of microbial communities from pristine soil under acute TBBPA stress, and achieved rapid screening of functional degraders. The results showed that TBBPA concentration and exposure time jointly drove community structural reconstruction, in which Methylobacillus and Pannonibacter, owing to their strong tolerance and high abundance, emerged as potential core degraders. Functional analysis indicated that high-concentration TBBPA (200 mg/L) reduced the abundance of the DLD gene by nearly 60%, whereas the community effectively alleviated energy metabolism inhibition through upregulation of upstream tricarboxylic acid cycle genes (CS, IDH3, and ACO) and respiratory chain functional genes (ccoN and ccoO), and formed a more tightly connected interaction network to enhance functional synergy. Metabolomic analysis revealed significant accumulation of membrane repair-related lipids (Gpetn and Lysopa) and amino acids (Norleucine and L-Phenylalanine), while pathways related to ABC transporters were activated, jointly confirming a stress adaptation mechanism centered on membrane repair and defense responses in the microbial community. The degradation process exhibited a multi-enzyme synergistic characteristic, with glutathione S-transferase playing a dominant role. After acclimation, the degradation efficiency of the microbial community was significantly improved, and the key strain Acinetobacter sp. T3 was successfully isolated. This study provides a theoretical basis and soil microbial communities for the development of in situ bioremediation technologies targeting persistent organic pollutants (POPs).

To address the decline in nitrogen removal performance of biological aerated filters (BAFs) caused by the inhibition of key denitrification processes by the arylpyrrole insecticide chlorfenapyr, this study established a nanoscale zero-valent iron (nZVI)-enhanced BAF system and systematically investigated the enhancement effects and regulatory mechanisms of nZVI. The results demonstrated that nZVI markedly improved shock load resistance and recovery resilience. The NH4+-N removal efficiency remained above 90% under different chlorfenapyr concentrations, while the total nitrogen (TN) removal efficiency reached up to 88.82%. Extracellular polymeric substance (EPS) analysis indicated that nZVI effectively mitigated the adverse effects of stress on the surface properties of the biofilm, maintaining the protein-to-polysaccharide ratio at approximately 2.0 and thereby preserving biofilm structural stability. High-throughput sequencing revealed that nZVI sustained microbial community diversity and evenness. The relative abundance of the dominant phylum Pseudomonadota consistently remained above 54%, and the targeted enrichment of functional genera such as Paracoccus and members of Rhizobiaceae was promoted. Integrated analysis of carbon and nitrogen metabolic pathways had revealed that nZVI, acting as an electron donor, had promoted the TCA cycle while significantly upregulating the expression of iron transport genes (afuABC) and key denitrification genes (napA, nirB, and nosZ). From the perspectives of electron transfer and microbial community ecology, this study elucidates the intrinsic mechanisms by which nZVI enhances the stress resistance of biological systems, providing a theoretical basis for the engineering treatment of refractory pesticide wastewater.

The synergistic toxicity of multi-metal composite pollution exacerbates environmental risks, highlighting the urgent need for efficient green remediation strategies. This study investigated the adsorption characteristics and underlying mechanisms of Beauveria bassiana Z1 exposed to exogenous jasmonic acid (JA) for six heavy metals in both single and composite systems. In single-metal systems (6 mM), strain Z1 showed the highest adsorption for Cd(II) (59.7 mg/g), which was significantly enhanced to 108.1 mg/g by JA treatment. JA improved the adsorption capacities for Cd(II), Co(II), Zn(II), Mn(II) and Ni(II) (ranked by adsorption capacity), and shortened the adsorption equilibrium time for Cu(II) and Mn(II). In the multi-metal system (total 6 mM), the adsorption capacity followed the order: Cd(II) > Mn(II) > Cu(II) > Co(II) > Zn(II) > Ni(II). JA treatment increased the total adsorption to 18.8 mg/g, compared to 15.8 mg/g in the control. SEM-EDS/TEM showed that strain Z1 mitigated metal toxicity via extracellular enrichment of metals such as Cd(II), Mn(II), Zn(II) and intracellular compartmentalization. FTIR and XRD analysis indicated the involvement of different surface functional groups and crystalline solids in biosorption of different metals. Transcriptomic analysis further revealed that exogenous JA treatment is associated with the upregulation of SPT15 (1.5-fold, 42.3% lower than under Cd(II) treatment alone), and it correlated with increased expression of key ABC transporter genes. This transcriptional cascade likely enhances heavy metal transport and intracellular chelation, contributing to the improved heavy metal biosorption observed in strain Z1. Moreover, in the multi-metal system, inter-metal competition exerts a stronger influence on heavy metal adsorption by strain Z1 than JA treatment.

Nanoscale zero-valent iron (nZVI) has been widely applied in aquatic pollution remediation, yet the regulatory mechanisms by which particle size influenced microbial denitrification remained unclear. Heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria were used as a model to systematically evaluate the effects of nZVI with different particle sizes (5-500 nm) on denitrification performance, iron metabolism, and global gene expression. Particle size was found to markedly govern nZVI corrosion and iron release, which in turn determined the direction of microbial metabolic responses. For 100 nm nZVI, a mild and sustained release of Fe2+ was produced and was efficiently taken up via cellular iron-transport system, resulting in synergistic activation of iron-storage pathways, the tricarboxylic acid (TCA) cycle, and the electron-transport chain. This response was associated with upregulation of key denitrification genes (nasA and nirB) and increased ammonium and total nitrogen removal by 10.9% and 15.7%, respectively. In contrast, rapid corrosion of 20 nm nZVI triggered a burst release of Fe3+ and reactive oxygen species (ROS), which forced cells into a stress-repair state dominated by ferric-iron transport system (afuA/B/C) and oxidative-damage repair (wrbA). Consequently, genes encoding key carbon metabolism enzymes and denitrification pathways were suppressed, nitrogen-removal capacity was impaired. This study elucidated the nZVI size effect along the "particle size-iron speciation-transport-metabolic network" cascade, thereby providing a mechanistic basis to guide the precise application of nZVI for microbially enhanced denitrification.

Industrial wastewater from battery manufacturing, metal smelting, and electroplating often contains high concentrations of cadmium and nitrogen, resulting in cadmium-nitrogen combined pollution. Conventional physicochemical methods for simultaneous removal of cadmium and nitrogen face limitations such as complex processes, high energy consumption, and risks of secondary pollution. In contrast, using cadmium-tolerant denitrifying microbes, which achieve synergistic removal of cadmium and nitrogen through adsorption, biomineralization, and other pathways, offers advantages of low energy consumption and high efficiency. In this review, we summarize the classification and denitrification characteristics of cadmium-tolerant denitrifying microbes, with a focus on the cadmium tolerance mechanisms and nitrogen removal performance of Pseudomonas as a representative microbial group. We analyze the inhibitory effects of cadmium on denitrification, explore the underlying molecular mechanisms, and summarize microbial response mechanisms and cadmium removal pathways under cadmium stress. In addition, we review the advances in the application of functional bacterial strains in various reactor systems for synergistic cadmium and nitrogen removal, and reviews the achievements in enhancing removal efficiency and system stability through biomineralization and carrier optimization. Finally, we discuss current challenges and limitations and makes an outlook on the future research directions, aiming to provide theoretical and practical insights for the bioremediation of wastewater co-contaminated with cadmium and nitrogen.

P-arsanilic acid (P-ASA), an antimicrobial and growth-promoting agent widely used in animal husbandry, has become a focal point of environmental concern due to its resistance to degradation and potential for water contamination. This study investigates the efficacy of a three-dimensional electro-Fenton (TD-EF) system for the removal of P-ASA from aqueous solutions. The TD-EF reactor was configured with a gas diffusion electrode (GDE) fabricated from ZIF-67-derived CoFe-MOF-C-700 and carbon black, paired with graphite as the anode and granular activated carbon impregnated with FeSO4 & sdot;7H2O as the particle electrode. The experimental findings indicated that the TD-EF system achieved a remarkable 97.4 % removal rate of P-ASA and a 51.2 % reduction in total organic carbon (TOC) within 100 min. Characterization and electrochemical analyses confirmed that the CoFe-MOF-C-700 composite exhibited a high density of active sites and superior catalytic efficiency in the oxygen reduction reaction. Notably, hydrogen peroxide generation was optimized, with an accumulation up to 67.5 mM after 60 min. The degradation process was significantly influenced by hydroxyl radicals and singlet oxygen, as evidenced by reactive oxygen species trapping and electron paramagnetic resonance experiments. Additionally, LC-MS analysis and DFT calculations provided insights into the degradation pathways of P-ASA, while EPI software evaluations and toxicity tests confirmed the environmentally friendly nature of the treated effluent. This research not only provides critical insights into the design and application of bimetallic metal-organic frameworks (MOFs) with enhanced catalytic performance but also underscores the potential of the TD-EF system as a sustainable technology for arsenic remediation.

Heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria possess considerable potential for treating high-ammonia wastewater; however, their denitrification characteristics and response mechanisms under microplastics (MPs) stress remain inadequately understood. This study systematically investigated the effects of typical MPs on the denitrification performance of HN-AD bacteria strain TAC-1 through batch experiments, metatranscriptomic and ultrastructural analysis. The findings demonstrated that hydrophobic nature of polyvinyl chloride (PVC) disrupted the intermolecular interactions among lipid molecules, reducing cell membrane density and forming permeable channels. This structural damage decreased the expression of the sulfate/sulfonate transport system (cysW/cysP/cysU/cysA), impairing bacterial protein synthesis. In response to survival pressure, the strain activated an immune evasion mechanism by upregulating the expression of fimbriae synthesis genes (fimA and fimD). ompared to PVC, polyethylene (PE), due to its high chemical stability, induced the disorganization of membrane lipids without significantly compromising membrane integrity. Notably, 100 nm PE particles enhanced the iron acquisition capability of the strain, leading to increases of 24.63 % in ammonia nitrogen (NH4+-N) removal rates. However, this promotional effect declined following prolonged exposure (>6 days) due to the accumulation of intracellular toxic substances. The cationic surface characteristics of polystyrene (PS) induced severe oxidative stress, leading to the most pronounced structural damage to the membrane. Although PS impaired denitrification efficiency by disrupting membrane integrity, it maintained NH4+-N conversion capacity through compensatory metabolic reorganization mediated by the glutamine synthetase and glutamate dehydrogenase pathways. These findings provide a theoretical foundation for enhancing the anti-interference resilience of biological wastewater treatment systems.

Microbial loss significantly affects wastewater treatment efficiency. This study simulated the inoculation area of a self-developed biological doubling reactor (BDR) to evaluate the retention efficiency of seven different fillers for aerobic denitrifying bacteria. Over 90 days of continuous operation, the porous filler R3 demonstrated excellent performance, with OD600 values consistently exceeding 1.0 and minimal fluctuation. On day 90, the seed liquid amplified with R3 achieved removal efficiencies of 100% for ammonia nitrogen, 97.75% for total nitrogen, and 96.4% for chemical oxygen demand, outperforming other fillers. Scanning electron microscopy and microscopic analysis revealed that R3's large large specific surface area and volume formed a unique meshed biofilm structure, enhancing oxygen and nutrient transport while minimizing detachment. This promoted effective enrichment and retention of aerobic denitrifying bacteria. Microbial diversity analysis confirmed that Acinetobacter, a key genus involved in aerobic denitrification, dominated the network biofilm on R3, accounting for an average of 35.63%. while granular fillers, due to oxygen limitation, promoted the growth of anaerobic ammonium-oxidizing Alcaligenes. The use of BDR-enhanced MBBR for treating synthetic wastewater resulted in a 29.6% increase in TN removal efficiency, with stable system operation. The use of porous fillers with a high specific volume supports stable biofilm formation and consistent seed liquid output, providing a viable solution to microbial loss in wastewater treatment processes.

The regulation of rhizosphere bacterial community structure and metabolism by plants in municipal solid waste landfills is a key to enhancing the biodegradation of chlorobenzene (CB). In this study, we employed biodiversity and metabolomics methods to systematically analyze the mechanisms of different plant species in regulating the rhizosphere bacterial community structure and metabolic features and then improved the methane (CH4) oxidation and CB degradation capacity. The results showed that the rhizosphere soil of Rumex acetosa exhibited the highest CH4 oxidation and CB degradation capacity of 0.08 g/(kg·h) and 1.72×10-6 g/(L·h), respectively, followed by the rhizosphere soil of Amaranthus spinosus L., with the rhizosphere soil of Broussonetia papyrifera showing the weakest activity. Rumex acetosa promoted the colonization of Methylocaldum in the rhizosphere, and the small-molecule organic amine, such as triethylamine and N-methyl-aniline, secreted from the roots of this plant enhanced the tricarboxylic acid cycle and nicotinamide metabolism, thereby increasing microbial activity and improving CH4 and CB degradation efficiency. Conversely, cinnamic acid and its derivatives secreted by Broussonetia papyrifera acted as autotoxins, inhibiting microbial activity and exacerbating the negative effects of salt stress on key microbes such as methanotrophs. This study probed into the mechanisms of typical plants growing in landfill cover soil in regulating bacterial ecological functions, offering theoretical support and practical guidance for the plant-microbe joint control of landfill gas pollution.

Heterotrophic nitrifying-aerobic denitrifying (HN-AD) bacteria with multi-stress tolerance hold significant potential for industrial wastewater treatment. In this study, a novel strain, Halomonas sp. ZC-1, was isolated from chemical wastewater and exhibited excellent nitrogen removal performance under low-temperature (10 degrees C) and high-salinity (0-13 %) conditions. Notably, at 10 degrees C and 10 % NaCl, ZC-1 achieved maximum ammonia and total nitrogen removal efficiencies of 94.9 % and 83.5 %, respectively, with a peak average ammonia removal rate of 3.36 mg/L/h. Transcriptomic analysis revealed that strain ZC-1 resists low-temperature and high-salinity stress through three key mechanisms: (1) upregulation of genes involved in osmoprotectant synthesis, such as betC and ectC, to regulate intracellular osmotic pressure; (2) activation of Na+ /H+ antiporters (mnhC, mnhE) and the K+ uptake gene phaF, maintaining ion homeostasis via the proton motive force; and (3) enhanced expression of 3-hydroxyacyl-[ACP] dehydratase (FabA) and beta-ketoacyl-[acyl-carrier-protein] synthase I (FabB), promoting fatty acid chain elongation and unsaturated fatty acid synthesis to lower membrane phase transition temperature. Furthermore, in practical applications treating saline wastewater at 10 degrees C, strain ZC-1 demonstrated ammonia and total nitrogen removal efficiencies of 66.92 % and 53.74 %, respectively. These findings elucidate the nitrogen removal mechanisms of ZC-1 under low-temperature and high-salinity conditions and highlight its potential as an effective candidate for treating complex industrial wastewater.

Emerging contaminants (ECs) have raised global concern due to their adverse effect on ecosystems and human health. However, the occurrence and transport of ECs in stormwater remain unclear. The impact of ECs from stormwater on surface water quality and ecosystem health is also poorly documented. In this review, we examined the variations in EC concentrations in surface water resulting from stormwater. During the wet weather, the concentrations of most investigated ECs, e.g., microplastics, per- and polyfluoroalkyl substances, and vehicle-related compounds, significantly increase in surface water, indicating that stormwater may be a critical source of these contaminants. Furthermore, the potential pathways of ECs from stormwater enter surface water are outlined. Studies demonstrate that surface runoff and combined sewer overflows are important pathways for ECs, with discharges comparable to or exceeding those from wastewater treatment plants. Illicit connection also plays an important part in elevated EC concentrations in surface water. Overall, our findings underscore the importance of stormwater as a source for ECs in surface waters, and urge for increased emphasis on, and reinforcement of, stormwater monitoring and control measures to minimize the transport of ECs into receiving water bodies.