In dryland ecosystems, cyanobacterial crust creates distinct microhabitats for underlying soil microbes, yet the drivers of microbial diversity and composition at regional scales remain poorly resolved. We assessed soil bacterial and fungal communities underlying cyanobacterial crust along a precipitation gradient in northwest China to identify key determinants, including climate, crust traits, and soil properties. We found that bacterial diversity and richness significantly exceeded those of fungi, with a notable decline in bacterial alpha diversity beyond a 300 mm mean annual precipitation (MAP) threshold. MAP exerted a strong direct effect on bacterial communities, while fungal assemblages were predominantly influenced by crust thickness, indicating that soil bacteria exhibit greater sensitivity to precipitation than fungi. Extracellular polymeric substances from cyanobacterial crust significantly enhanced bacterial diversity, underscoring the role of crust traits in mediating microbial responses. Network analyses indicated increased complexity and cooperation of microbial interactions under reduced precipitation, with fungal networks exhibiting greater stability than bacterial networks. These findings highlight cyanobacterial crust as protective microhabitats that mitigate aridity effects on soil microbes and illustrate the differential sensitivity of bacterial and fungal communities to precipitation changes. This study provides mechanistic insights into microbial responses to precipitation gradients and emphasizes the importance of cyanobacterial crust in sustaining microbial-mediated functions in dryland under ongoing climate change.

Organic carbon scarcity limits advanced nitrogen removal from wastewater treatment plant effluent. This study proposes a dredged-sludge-derived sulfide-iron-based biochar (SBC-Fe-S) as a multifunctional biofilter medium to enable coupled sulfur-autotrophic denitrification and Anammox. The SBC-Fe-S-packed biofilter integrates waste-sludge reclamation, sustained release of electron donors (S2−/Fe2+), microbial immobilization, and selective NH4+-N adsorption, effectively circumventing the electron donor instability and external-carbon dependence of conventional systems. This design overcomes limitations of conventional sulfur- or iron-based systems that rely on unstable or externally supplied electron donors. Adsorption experiments confirmed strong, selective NH4+-N adsorption, whereas long-term operation demonstrated that nitrogen removal was driven primarily by biological transformation rather than adsorption. The system achieved stable start-up within 91 days, attaining 86.4

Perfluorooctanoic acid (PFOA) is an emerging pollutant frequently detected in nitrogenous wastewater. In this study, the transformation of PFOA in an Anammox system was investigated using ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and density functional theory (DFT) calculations. Additionally, the synergistic removal of nitrogen, as well as the evolution of the microbial community and functional genes in response to PFOA (at concentrations of 0.001-100 & micro;g/L) were examined. Results showed that PFOA was primarily adsorbed into the biofilm while biotransformation also occurred, which was achieved via defluorination pathways and initiated by carboxylate-mediated decarboxylation. Several transformation products were detected, most of which exhibited lower toxicity than PFOA. 0.001 & micro;g/L of PFOA had slight influence on nitrogen removal, whereas 1-100 & micro;g/L continuously suppressed it. As a protective strategy, Anammox system up-regulated the growth of anaerobic ammonia-oxidizing bacteria (AnAOB). However, the gene abundance associated nitrate reduction (narG) and nitrite reduction (nirS and nirK) both increased, which may hinder nitrite consumption by AnAOB. In conclusion, when treating PFOA-containing wastewater using the Anammox process, the activity of denitrifying and nitrifying bacteria should be maximally inhibited, while the biotransformation of PFOA should be enhanced. These findings provided a new perspective for the synergistic removal of PFOA and nitrogen.

Microplastics (MPs) and cadmium (Cd) co-contamination in agricultural soils poses an increasing threat to global food security, while the species-specific mechanisms underlying crop responses to co-contamination remain poorly understood for major cereal crops. This study investigated the interactive effects of different concentrations of polyvinyl chloride microplastics (PVC-MPs) (0.1%, 1%, and 10% w/w) and Cd (5 mg/kg) on the growth physiology of wheat and maize seedlings, as well as the associated rhizosphere soil microecological properties. Our results showed that under combined stress conditions, maize adopted an active defense mechanism characterized by robust antioxidant upregulation and restricted root-to-shoot Cd translocation. In contrast, wheat exhibited a passive tolerance phenotype under Cd stress alone. With the addition of PVC-MPs, the antioxidant system was activated to counteract oxidative damage. However, it was still more prone to Cd accumulation in shoots at moderate PVC-MPs concentrations. Low concentrations of PVC-MPs (0.1% and 1%) can alleviate Cd phytotoxicity in both crops, while 10% PVC-MPs caused synergistic toxicity and significantly inhibit growth. Critically, redundancy analysis, structural equation modeling, and random forest analysis identified soil available phosphorus as the primary driver mediating seedling growth under co-contamination, overriding the effects of nitrogen. High concentrations of PVC-MPs inhibited the activity of alkaline phosphatase, creating a bottleneck in phosphorus metabolism and thereby limiting productivity. These findings clarify the interaction mechanisms between PVC-MPs and Cd in the soil-plant system and highlight that regulating soil phosphorus availability could be a vital strategy for the remediation of MP-Cd co-contaminated farmlands.

With stricter sewage discharge standards, wastewater treatment plants (WWTPs) are increasingly seeking advanced nitrogen removal technologies. This study explored two biofilters that combine sulfur autotrophic denitrification (SAD) with Anammox (SAD/A), using volcanic rock and Fe/S-modified biochar as fillers, respectively, to treat secondary effluent from a municipal WWTP. The results indicated that low-concentration secondary effluent posed challenges for maintaining stable nitrogen removal in the biofilters. However, introducing primary effluent to supplement the nitrogen substrate significantly improved nitrogen removal performance. During the stable operation phase, the average total nitrogen removal efficiency (TNRE) of the two biofilters reached 91.3% and 93.4%, respectively, with the average effluent total nitrogen (TN) concentration dropping below 1.5 mg L- 1. The volcanic rock biofilter (VR-BF) reduced sulfate production by 48% compared to a single SAD system. On the other hand, the biochar biofilter (BC-BF) introduced an iron redox cycling-driven denitrification pathway, resulting in superior nitrogen removal performance. Nitrite reductase (NIR) activity and Heme-c content increased by 157.0% and 215.5% in the VR-BF, and by 135.1% and 389.3% in the BC-BF, respectively. High-throughput sequencing revealed that Thiobacillus and Sulfurimonas were the dominant genera in both biofilters. Additionally, iron redox cycling genera, Ferritrophicum and Geothrix, were detected in the BC-BF. This study presents a technology capable of achieving advanced nitrogen removal from secondary effluent.

This study explored the effects of perfluorooctanoic acid (PFOA) on river sediment denitrification and its remediation using a coupled sulfur autotrophic denitrifying-Anammox microbial consortia. River sediments possessed intrinsic denitrification potential. However, PFOA did not inhibit ammonia nitrogen removal but accelerated nitrite oxidation, causing nitrate accumulation, altering the contents of extracellular polymeric substances and soluble microbial products, inhibiting heme-c secretion, and elevating nitrite reductase activity (0.22-0.93 ng nitrite/(min·mg protein)). After microbial enhancement, sediment PFOA tolerance and denitrification improved (initial ammonia removal rate was 0.247 mg/(g·day)), while heme-c secretion remained unaffected and nitrite reductase elevation showed PFOA concentration dependence. PFOA reduced the abundance of Proteobacteria and Sulfithrix in native sediments, whereas microbially enhanced communities exhibited higher stability. Enrichment of functional genes (hzsB, amoA) enhanced denitrification and stress resistance, providing insights and technical support for PFOA-contaminated sediment bioremediation.

Via a sol-gel route, we synthesized a ternary type-II/Schottky heterojunction g-C3N4/TiO2/MXene (GTM) photothermal catalyst that harnessed residual heat from industrial flue gas together with sunlight to achieve efficient CO2 reduction without external energy input. Under low-temperature photothermal conditions (80 degrees C + sunlight), GTM achieved a CO production rate of 349.3 mu mol g-1 h-1 with 100% selectivity, representing enhancements by 12.7 times over photocatalysis (27.5 mu mol g-1 h-1) and 81.2 times over thermocatalysis (4.3 mu mol g-1 h-1), evidencing a pronounced photothermal synergy. Integrated characterization and density functional theory (DFT) analysis clarified the origin of this synergy: under illumination, aided by the excellent photothermal conversion capability and high electrical conductivity of MXene, the catalyst surface heated rapidly and photogenerated electrons from g-C3N4 and TiO2 migrated swiftly to MXene, where CO2 was activated into a bent adsorption configuration, strengthened adsorption and lowered the formation barrier of the key intermediate COOH*. Thermal input, on the one hand, excited localized surface plasmon resonance (LSPR) effect in MXene, generated abundant hot carriers; on the other hand, it accelerated surface molecular motion, enhanced H2O adsorption/dissociation, lowered the free energy of the rate-determining step, and promoted CO desorption. The complementary advantages of the three components and the superposition of light and heat effects markedly boosted the CO2-to-CO rate under mild conditions, offering a feasible pathway for industrial flue-gas treatment and carbon resource utilization.

g-C3N4/PDI-g-C3N4 homojunction (CPCN-X) was prepared to effectively remove sulfamethoxazole (SMX) from water under visible light. The band of CPCN-X bent and the new flat band potential resulted in the generation of a built-in electric field at the contact interface between PDI-g-C3N4 (CNPDI) and g-C3N4 (CN). This facilitated interlayer charge migration, optimized the transportation efficiency of photoinduced electron pairs, and thereby boosted photocatalytic activity. CPCN-6 photocatalyst prepared with a mass ratio of 1:6 (CNPDI to CN) exhibited the highest photocatalytic activity, which can degrade 97.0 % of SMX after 90 min of visible light irradiation. The related degradation rate constant was calculated as 0.0371 min(-1), which was a 2.3 and 4.7 fold increase in comparison to CNPDI and CN, respectively. Free radical scavenging experiments revealed that center dot O-2(-) and h(+) were the predominant active materials for the photocatalytic decomposition of SMX by CPCN-6, while center dot OH and O-1(2) exhibited a relatively negligible contribution. It was found that CPCN-6 exhibited the potential to degrade sulfonamide antibiotics and the limited ability to remove atrazine and phenol in the visible light region due to the difference of redox properties and molecular structure.

Gels with excellent ionic conductivity and high-humidity resistance are highly desired in practical applications due to their potential to create wearable soft electronics that maintain reliable performance under humid conditions. Herein, we designed a fully hydrophobic eutectogel by one-step copolymerization of glycidyl methacrylate and 2-phenoxyethyl acrylate within a hydrophobic deep eutectic solvent (DES) composed of 1-allyl-3-methylimidazolium chloride and methyl 4-hydroxybenzoate. The optimized eutectogel exhibited exceptional moisture tolerance, featuring a water contact angle > 107 degrees and humidity-insensitive ionic conductivity (0.10 mScm(-1) at 90% RH). Subsequently, we fabricated a strain sensor that demonstrated stable resistance responses to multi-scale human motions, such as finger, wrist, and elbow joint bending, under both ambient and high-humidity conditions. This stability arose from the covalently crosslinked hydrophobic polymer network and non-hygroscopic DES, effectively mitigating water-induced sensing instability. The hydrophobic eutectogel sensor establishes a transformative platform for next-generation wearables in personalized healthcare and extreme-condition sensing.

This study examined how pristine polypropylene microplastics (PP-MPs) affect carbon (C), nitrogen (N), and phosphorus (P) stoichiometry across the soil-maize continuum. Under PP-MPs stress, soil organic C increased, soil total N first increased and then decreased with increasing PP-MPs concentration, while soil total P did not change significantly, leading to increased soil C:N and decreased N:P, indicating microbial P limitation. Microbial biomass C increased and biomass P decreased, while biomass N was unchanged, raising the microbial C:N:P ratio and reinforcing exacerbated microbial P limitation. Enzyme activities shifted from C- to N- and P-acquisition, and vector analysis confirmed that PP-MPs alleviated microbial C limitation but sustained P limitation. Maize growth exhibited a concentration-dependent biphasic response, low PP-MPs levels (≤2%) promoted root biomass and root-to-shoot ratio, whereas high levels (≥5%) strongly inhibited both shoot and root growth. Notably, the R/S ratio remained elevated even at inhibitory concentrations, suggesting a preferential allocation of biomass to root under PP-MPs stress. Root showed sensitive homeostasis for N and N:P, whereas shoot maintained strict homeostasis for P and N:P, indicating a strong regulatory capacity of photosynthetic tissues to buffer against microbially mediated soil P limitation under PP-MPs stress. Structural equation modeling identified that PP-MPs affect maize growth through integrated pathways, directly via phytotoxicity and indirectly by modifying soil physical properties, microbial biomass, and enzyme activities. These findings establish a chemometric framework linking microplastic pollution to nutrient remodeling and seedling adaptability in maize, providing mechanistic insights into the risks posed by microplastics to soil-plant systems during early growth stages.

Among the diverse pollutants emitted from coal-fired and non-ferrous metal smelting flue gas, Hg0 and CO have emerged as globally concerning environmental pollutants. However, the simultaneous abatement of multiple pollutants remains a critical challenge to be addressed. In this study, cobalt nanoclusters (Co NCs) were anchored on the terminal oxygen of Ti-O on Ti3C2 MXene and formed asymmetric oxygen vacancies Co-Ov-Ti via a onestep hydrothermal method, yielding Co NCs/Ti3C2 MXene with a morphology of hierarchical nanosheetassembled spheres for Hg0 and CO catalytic oxidation. Co NCs/Ti3C2 MXene exhibited excellent 44 % and 52 % of Hg0 and CO simultaneous removal efficiency at the optimal temperature of 250 degrees C, respectively. DFT calculations combined with energy barrier modeling were employed to investigate the reaction pathways and energy variations during the catalytic oxidation of Hg0 and CO. Specifically, Hg0 oxidation follows the Eley-Rideal mechanism, with a rate-determining energy barrier of 2.11 eV, while CO oxidation adheres to the Langmuir-Hinshelwood mechanism, featuring a rate-determining barrier of 0.17 eV. In the co-catalytic oxidation process, competitive adsorption between Hg0 and CO was observed, primarily manifested as competition for Ov on the catalyst surface. This study provides a novel strategy for the synergistic control of multi-pollutants in industrial flue gas.

Municipal solid waste incineration (MSWI) is an important anthropogenic source of elemental mercury (Hg0) emissions. In MSWI flue gas treatment, achieving efficient Hg0 oxidation relies on the active participation of HCl under typical downstream operating conditions (<200 °C). However, the activation of HCl remains a formidable challenge at low temperatures. Herein, we rationally design a perovskite oxide catalyst featuring Ru-O-Mn coordinated active sites to promote HCl activation via a low-temperature Deacon-like pathway, enabling efficient in situ Cl* generation for Hg0 oxidation. The optimized catalyst achieves over 99% conversion of Hg0 to Hg2+ at 150 °C. Combined experimental characterization with density functional theory (DFT) calculations demonstrates that Ru incorporation markedly enhances O2 dissociation at the Ru-O-Mn interfacial sites and substantially lowers the energy barrier for HCl dehydrogenation by 0.52 eV, thereby promoting Cl* formation. The generated Cl* species further interact with surface oxygen (O*) to form highly reactive ClOx intermediates, which facilitate HgCl2 formation and significantly improve Hg0 oxidation efficiency. This work provides fundamental insights into low-temperature HCl activation and offers a promising strategy for mercury abatement in incineration flue gas.

A g-C 3 N 4 /TiO 2 /MXene heterojunction harnesses industrial waste heat (80 °C) and sunlight to selectively convert flue-gas CO 2 to CO with 100% selectivity, achieving a rate of 349.3 μmol g −1 h −1 via pronounced photothermal synergy.

As a substitute for bisphenol A, bisphenol S (BPS) is increasingly detected in various environmental matrices. Autotrophic microorganisms within the Completely Autotrophic Nitrogen removal Over Nitrite (CANON) process are highly sensitive to changes in water quality. This study evaluated the effects of BPS, at concentrations ranging from 1 ng/L to 1 mg/L, on CANON process and assessed its capacity for synergistic removal of nitrogen and BPS. Following the addition of 1 ng/L and 1 mu g/L BPS, the ammonia removal efficiency (ARE) and total nitrogen removal efficiency (TNRE) remained stable at 88.1 % and 76.9 %, respectively. The removal efficiency at 1 mu g/L of BPS reached 25 %. In contrast, exposure to 1 mg/L BPS resulted in a significant decline in both ARE and TNRE to 50.1 % and 37.6 %, respectively, indicating that CANON process could not tolerate 1 mg/L of BPS. BPS was biodegraded into p-hydroxybenzenesulfonic acid, a metabolite with lower ecotoxicity than BPS. Enhanced biodegradation of BPS thus contributed to the alleviation of its inhibitory effects on microbial activity. Microbial diversity increased after BPS exposure, although species richness declined. Pseudomonadota became the dominant phylum, increasing in relative abundance from 24.75 % to 51.98 %. The relative abundance of Nitrosomonas decreased from 15.44 % to 1.23 %, and that of Candidatus_Kuenenia decreased from 23.09 % to 9.92 %. The CANON system was feasible for treating nitrogenous wastewater containing BPS below 1 mg/L.

Bisphenol A (BPA) is one of the most frequently detected endocrine disruptors in water environment, with high content levels. This study explored the effects of various concentrations of BPA on the MBR-Anammox system and removal mechanism. Results showed that MBR-Anammox system achieving > 90 % BPA removal and stable total nitrogen removal rate (TNRR) (0.273-0.290 kg Nm(-)(3)d(-)(1)) through dual-phase adaptation. The removal of BPA mainly depends on the combined action of flocculent sludge and membrane sludge. Low concentrations (<10 mu gL-1) of BPA stimulated extracellular polymeric substances secretion and maintained the activity of enzymes such as HAO, AMO, NIR, and heme c content. High concentrations (>= 10 mu gL-1) of BPA significantly inhibited the enzyme activity and heme c content. However, it compensates for the adverse effects of reduced enzyme activity by promoting the proliferation of Candidatus_Kuenenia, norank_f__norank_o__SBR1031, Stenotrophobacter, Areimonas, as well as the replication of hzsB and nirS genes, in order to maintain stable operating performance. In summary, the MBR-Anammox system is suitable for treating the nitrogenous wastewater containing high concentrations of BPA, such as landfill leachate, domestic sewage, etc.

Ibuprofen (IBU), a commonly used non-steroidal anti-inflammatory drug, is frequently detected in wastewater treatment systems, where it can interfere with nitrogen removal. This study investigated the effects of IBU on nitrogen removal performance and its biotransformation in a coupled sulfur autotrophic denitrification and anammox (SAD/A) system. Moreover, key parameters, such as nitrogen removal efficiency, microbial activity, community structure, and IBU degradation products, were carefully monitored. While IBU concentrations of up to 1mg/L had negligible impacts on nitrogen removal efficiency due to the counteracting effects of slight inhibition on anammox and enhancement of sulfur autotrophic denitrification, a significant inhibition of ammonia removal occurred when the concentration increased to 10mg/L. Quantum chemical analyses revealed that IBU underwent biotransformation through decarboxylation and hydroxylation pathways, leading to the formation of two biotransformation products with high ecological toxicity. This study is the first to elucidate the mechanisms by which IBU influences microbial communities and metabolic activities in SAD/A systems. In addition, it highlights the resilience of these systems in maintaining nitrogen removal efficiency under varying IBU concentrations, as well as the environmental risks posed by the biotransformation products of IBU.

The inverse vulcanization of elemental sulfur has been widely explored to synthesize sulfur-rich copolymers for mercury ion (Hg2+) adsorption in wastewater. However, the practical application of these materials is severely limited by their suboptimal adsorption rates and capacities. In this study, we report a scalable synthesis strategy for sulfur-rich copolymers (SPCs) through catalytic graft copolymerization combined with inverse vulcanization. The introduction of zinc diethyl dithiocarbamate (ZnDTC) enables the coordination of zinc ions' d orbitals with the lone pair electrons of active sulfur and the it-electron clouds of olefin carbons, facilitating the direct conjugation of sulfur with olefin double bonds. Density functional theory calculations reveal that the Gibbs free energy of ZnDTC-catalyzed SPCs is-29.6 kJ center dot mol-1, much higher than that without catalyst (-5.6 kJ center dot mol-1), indicating a substantially enhanced spontaneity of the reaction. Experimental results demonstrate that the synthesized SPCs achieve an exceptional Hg2+ adsorption capacity of 361 mg center dot g-1 within 30 s. For industrial water wastewater, 99.99 % Hg2+ removal efficiency can be achieved. It can be used for rapid purification of mercury-containing wastewater with any concentration gradient. This study introduces a catalytic boosting method for sulfur-containing materials, providing an effective solution for heavy metal removal and recycling of mercury waste.

This study employs a photodeposition method to load Ag and Pt nanoparticles onto the surface and interlayered structure of MXene, developing an efficient catalyst for CO2 reduction in industrial flue gas. The catalyst exhibits excellent thermal catalytic performance within a low-temperature range of 60-100 °C, achieving CH4 and CO production rates of 461 μmol g-1 h-1 and 86 μmol g-1 h-1, respectively, with a CH4 selectivity of 84.3 %. This temperature range requires no additional heating, relying solely on residual heat from flue gas, which offers a distinct temperature advantage and high catalytic efficiency compared to most thermal and photothermal CO2 reduction processes. Under simulated sunlight and at 100 °C, the production rates for CH4 and CO are 34 μmol g-1 h-1 and 589 μmol g-1 h-1, respectively, with a CO selectivity of 94.5 %. Notably, the catalyst demonstrates dual-product selectivity under varying experimental conditions. Experimental characterization and density functional theory (DFT) calculations reveal the thermodynamic and kinetic mechanisms underlying the enhanced production rates and selectivity shifts in both thermal and photothermal catalysis, detailing the CO2 reduction pathways and Gibbs free energy changes across conditions. This study not only provides a new approach for low temperature CO2 catalytic reduction but also offers valuable insights into dual-product selectivity, demonstrating great potential for practical applications in industrial flue gas management.

Molybdenum disulfide (MoS2) is considered a favorable absorbent for removing heavy metals. However, due to its various morphologies, MoS2 exhibits significant differences in its performance for removing mercury from flue gas. In the present study, the flower-like, spherical MoS2 and W-MoS2 were prepared by regulating the interlayer spacing and doping tungsten (W) in MoS2 for removing gaseous mercury (Hg0). The results show that the number of active sulfur sites (S2- and S22-) was critical to the adsorption performance of MoS2 for Hg0. The flower-like MoS2 demonstrated optimum properties below 125 degrees C which attributed to the presence of dominated S2- sites, while spherical MoS2 and W-MoS2 showed a wider application temperature range (up to 175 degrees C) during Hg0 removal which attributed to the unsaturated sulfur S22- and active oxygen. In terms of the mechanism, Hg0 is directly inserted into the Mo-S bond of MoS2 to form a transition state [HgMo]-S, and then the original Mo-S is interrupted to form a new beta-Hg-S bond, or combine with surface oxidation to form HgO. The oxygen in the flue gas can supplement the surface active oxygen on the MoS2, which enables the circulation of Mo5+. Hg0 also reacted with S22- to form alpha-HgS.

Converting CO2 from flue gas into valuable chemicals has always been an important research field. This study developed a thermally assisted photocatalytic reduction of flue gas CO2 system at the gas-solid interface, utilizing an NH2-MXene/TiO2/ZnTCPP (Zn-NMT) composite. Zn-NMT exhibited a CO generation rate of 236.17 mu mol center dot g- 1 center dot h- 1 at 80 degrees C with thermal assistance, achieving 100 % CO selectivity. Notably, it showed superior cyclic stability at 88 %, significantly surpassing the NMT (39 %). The findings indicated that the introduction of photosensitizer ZnTCPP expands the light absorption spectrum, thereby enhancing photonic utilization efficiency. Moreover, ZnTCPP and TiO2 can form an S-scheme heterojunction, and the use of MXene as a charge transport bridge effectively suppresses the recombination of electron-hole pairs generated by photoexcitation, which in turn notably extends the catalyst's longevity. Zn-NMT catalyst shows great potential in reducing CO2 emissions from flue gas and promoting the utilization of CO2 resources, offering new insights and methods for related fields.