The large accumulation of iron ore tailings (IOT) can easily lead to serious environmental pollution and dam-break risk. In this study, IOT was used together with silica fume and bauxite to prepare geopolymer eco-bricks (IEB). The influences of silica-alumina (Si/Al) molar ratio on compressive strength, water loss, alkalinity, gel products, microstructure and pore distribution were investigated. The formation and efflorescence mechanisms of IEB were revealed using XRD, FTIR, SEM and MIP analyses. The IEB with a Si/Al molar ratio of 1.98 exhibited the best comprehensive performance, and the content of N(C)-(A)-S-H gel exhibited a trend of initial increase followed by a decrease. The formation process of IEB involves the dissolution of Si-Al components, monomer condensation and gel formation, and the construction of a three-dimensional network structure. Both the Si/Al molar ratio and pore structure affected the efflorescence degree, and an appropriate proportion can reduce efflorescence. Soaking in 3% FeSO4 solution was an ideal chemical method for alkali reduction. Elymus dahuricus and Puccinellia tenuiflora were suitable for planting on IEB. This study provides theoretical support for the performance optimization, practical application and large-scale resource utilization of IEB.

The removal of lead (Pb(II)) from wastewater is of critical importance for effective wastewater treatment. In this study, industrial solid waste red mud (RM) and corn straw were used as raw materials to prepare magnetic RM-based biochar (RMBC) via co-pyrolysis. The physicochemical properties of RMBC were characterized using scanning electron microscopy, Brunauer–Emmett–Teller (BET), x-ray diffraction, Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, and vibrating sample magnetometer. The results confirmed the successful synthesis of RMBC with a relatively large specific surface area (BET = 126.614 m ^2 g ^−1 ) and abundant surface functional groups. During the pyrolysis process, Fe _2 O _3 in RM was partially converted into Fe _3 O _4 , endowing RMBC with favorable magnetic properties (saturation magnetization, M _s = 9.43 emu g ^−1 ). Batch adsorption experiments demonstrated that RMBC achieved a Pb(II) removal efficiency of up to 85.35%. The adsorption behavior was better described by the Freundlich isotherm model and the pseudo-second-order kinetic model, indicating a multilayer adsorption process dominated by chemisorption. Thermodynamic analysis revealed that the adsorption of Pb(II) was spontaneous and endothermic. Mechanism analysis indicated that Pb(II) removal by RMBC was governed by the synergistic effects of surface complexation, ion exchange, and redox reactions involving Fe _3 O _4 . Furthermore, Pb(II)-loaded RMBC could be efficiently separated and recovered from aqueous solution using an external magnetic field. This study demonstrates a feasible strategy for preparing an efficient and low-cost Pb(II) adsorbent through the co-pyrolysis of RM and corn straw while simultaneously promoting the resource utilization of industrial solid waste and agricultural waste.

Due to anthropogenic carbon dioxide (CO2) emissions, open oceans are acidifying, and the acidification rate is relatively stable. While coastal waters experience even greater pH fluctuations from terrestrial inputs, upwelling, and biological activity, this variability necessitates detailed long-term research in these regions. Based on field observations and historical literature data from 1980 to 2016, the interannual variability of seawater pH and its driving mechanisms were analyzed in Jiaozhou Bay, a highly human-perturbed bay in China. The results revealed an overall decreasing trend in pH over the three-decade period, with a decline rate of 0.0062 years-1, which is 3.6 times faster than that observed in the open ocean, indicating significant anthropogenic impacts on pH variations in Jiaozhou Bay. The long-term pH changes showed strong correlations with coastal environmental pollution status, characterized by three distinct phases: a decline from 1980 to 1986, followed by an increase during 1991 to 2004, and subsequently another decreasing trend from 2004 to 2016. Terrestrial (including wastewater) inputs were identified as predominant anthropogenic factors influencing these pH variations. Furthermore, this study highlights that while future management should focus on reducing organic matter and nutrient inputs, particular attention should be paid to the direct impacts of dissolved inorganic carbon (DIC) from treated wastewater discharge on pH reduction.

Rural black-odorous waterbodies (RBOWBs) represent a critical environmental challenge in China, yet the vertical stratification of sedimentary bacterial communities and its underlying drivers remain poorly understood. This study combined 16S rRNA gene amplicon sequencing across five sediment depths (0-125 cm) with shotgun metagenomic analysis of surface sediments to investigate bacterial diversity, composition, and functional potential in typical rural black-odorous systems of Dongming County, Shandong Province. Results showed a clear decline in bacterial richness with increasing sediment depth, with the surface layer (0-25 cm) exhibiting 1.2-1.9 times higher diversity than deeper strata. Community composition displayed distinct vertical zonation: Chloroflexi and Thiobacillus dominated surface layers and were linked to carbon hydrolysis and desulfurization, whereas Bacillus and nitrifying bacteria prevailed in deeper anoxic layers. Metagenomic analysis revealed high genetic potential for carbohydrate metabolism, amino acid biosynthesis, and sulfur-nitrogen cycling, with glycoside hydrolases (GHs) and glycosyl transferases (GTs) being particularly abundant. Statistical correlations identified total phosphorus (TP1), dissolved oxygen (DO), and pH of the overlying water-rather than sediment intrinsic nutrients-as the primary environmental factors associated with microbial functional stratification. These findings provide a mechanistic understanding of vertical microbial zonation in rural black-odorous sediment and offer a microbiological basis for developing depth-resolved sustainable remediation strategies.

This study pioneers a sustainable "waste-to-wealth" strategy for fabricating a high-performance, pH-universal Fenton-like catalyst (FeCu2@BCT4) through the one-step co-pyrolysis of acid-precipitated black liquor (APBL) and Fenton sludge with a copper precursor. The innovation lies in the precise engineering of a Fe-0/Fe3O4 heterojunction synergistically coupled with Cu-0 nanoparticles on a functional APBL-derived biochar. By tuning the Cu/Fe mass ratio and pyrolysis time, the phase composition and electron-transfer properties were optimized. The resulting catalyst exhibits exceptional activity and stability across a broad pH range (3-9), achieving >92.3% methylene blue degradation within 60 min, and demonstrates superior removal efficiency toward various cationic dyes (rhodamine B, crystal violet, malachite green) and an anionic dye (methyl orange). Mechanistic investigations reveal a clear pH-governed transition of reactive oxygen species (ROS) pathways: under acidic conditions (pH 3), center dot OH-dominated homogeneous-heterogeneous catalysis prevails; under neutral conditions, the system shifts to a heterogeneous process driven by synergistic center dot OH/O-1(2) oxidation. This unique ROS switch is sustained by efficient electron mediation from the biochar matrix, coupled with robust electron supply and transfer enabled by the Fe-0/Fe3O4 heterojunction and FeCu galvanic coupling. This work provides a novel paradigm for converting industrial solid wastes into advanced catalytic materials with a well-elucidated mechanism, effectively overcoming the critical pH limitation of conventional Fenton technologies and showing broad application prospects for organic wastewater remediation.

Two Fe-Mn modified rice-straw biochars (F/M-RSBC and FM-RSBC) were prepared and evaluated as peroxymonosulfate (PMS) activators for tetracycline (TC) degradation. Under optimal conditions, both catalysts achieved > 90% TC removal. Mechanistic investigations, supported by quenching experiments, electrochemical analysis, and post-reaction characterization, identified distinct activation pathways. The continuous block-like coating of FM-RSBC facilitated a surface-confined non-radical electron-transfer process, in which surface-stabilized PMS complexes directly oxidized TC. In contrast, the dispersed granular particles within pores of F/M-RSBC promoted a combination of radical (center dot OH, SO4 center dot-, and O-2(center dot-)) and non-radical (O-1(2)) pathways. Both catalysts maintained effective TC removal (> 80%) under the influence of humic acid or other common anions and in tap water and demonstrated good reusability over five cycles in double-distilled water and tap water. These findings elucidate structure-dependent PMS activation mechanisms and provide a framework for designing efficient, stable antibiotic degradation catalysts.

The high salinity of industrial wastewater poses a serious challenge to the performance of biological nitrogen removal (BNR). At present, there is a knowledge gap in identifying key salinity-tolerant nitrogen-removal microorganisms and understanding the functional mechanisms driving their activity, which seriously limits the optimization of efficiency and BNR research. In this study, an integrated analytical workflow was established. This workflow enabled the identification of key microorganisms and the elucidation of their functional mechanisms in salinity-tolerant nitrogen removal. Based on 190 activated sludge samples collected from industrial wastewater treatment plants in eastern China, key functional modules related to salinity tolerance and nitrogen removal were resolved via co-occurrence network analysis. Subsequently, multiple methods, including network topology, co-expression patterns, and random forests, were integrated to comprehensively screen taxa within the modules, aiming to pinpoint microbial groups that possess both functional importance and topological centrality in the network, and to dissect their functional driving mechanisms under high salinity stress systematically. The results showed that salinity significantly influenced community structure and function, with 8-12 g/L identified as the critical salinity range. The screened core salinity-tolerant microorganisms included Thioalkalivibrio and Hyphomicrobium, while core nitrogen-removing microorganisms included Thauera and Comamonadaceae; Parvibaculum and other taxa exhibited dual functional potential. Under high salinity conditions, nitrogen metabolism was remodeled. Nitrification and denitrification gene abundances decreased by 20-56%, and the dissimilatory and assimilatory nitrate reduction (DNRA, ANRA) pathways increased by about 25% and 16%, respectively. The salinity-tolerance strategy also changes from ion accumulation to compatible solute synthesis or antioxidant stress responses. These gene groups were upregulated by about 10-59% and 17-106%, respectively. In a high salinity environment, key microorganisms mediate niche differentiation and energy redistribution within the microbial community, thereby facilitating collaborative remodeling of salinity tolerance and nitrogen removal. At the same time, although the microbial co-occurrence network became less dense, the roles of key microorganisms became more prominent. This study systematically established a framework for identifying key microorganisms and characterizing their functional mechanisms in the salinity-tolerant nitrogen removal process for industrial wastewater, providing a new theoretical basis for optimizing the BNR process for high salinity wastewater.

Mining pit lakes formed by acid mine drainage (AMD) represent extreme environments that serve as model systems for studying microbial ecological interactions under environmental stress. While microalgae-bacteria interactions are well-documented in neutral waters, their patterns and drivers in acidic systems remain poorly understood. This study systematically investigated the microbial communities in five pit lakes along a gradient of AMD impact using integrated 16S and 18S rRNA gene sequencing, water geochemistry, and multivariate statistical analysis. The study found that acidic pit lakes (APLs) and circumneutral pit lakes (CPLs) harbored fundamentally distinct microbial communities. pH was identified as the paramount environmental filter, overriding other factors in shaping both microbial richness and community structure, as revealed by random forest and Mantel tests. The richness of both microalgae and bacteria decreased significantly with increasing acidity. Cross-kingdom co-occurrence network analysis revealed more complex co-occurrence patterns and tighter potential associations between microalgae and bacteria in APLs, with lower network modularity. These findings are consistent with the ecological hypothesis that environmental stress may concentrate or intensify microbial associations. Putative keystone taxa, including acidophilic microalgae (Chlorellaceae) and bacteria (Acetobacteraceae), were identified as central players in the APLs network. The findings provide new insights into the microbial community assembly in extreme acidic environments, highlighting the interplay between stringent environmental filtering and cross-kingdom interactions. The understanding facilitates the development of bioremediation strategies for AMD ecosystems that are based on microbial interactions.

Land snail shells represent a rapidly accumulating, high-resolution terrestrial archive with unique potential for reconstructing past weather-scale environmental changes. To date, studies relied exclusively on the oxygen isotopes in shells, leaving the potential of other proxies (i.e., trace-element ratios) largely unexplored. Here, we present the first in-situ, high-resolution profiles of Na/Ca, Mg/Ca, Sr/Ca, Ba/Ca, and Mn/Ca from modern Cathaica fasciola shells collected from the Chinese Loess Plateau. Na/Ca, Sr/Ca, and Ba/Ca exhibit consistent covariation, likely reflecting shared lattice-substitution behavior and transport pathways, whereas Mg/Ca and Mn/Ca may be more influenced by organic mediation and local calcification dynamics. Trace-element incorporation may be jointly controlled by biological processes and environmental forcing, including growth rate, calcification dynamics and hydro-chemical variability. Weather-scale rainfall events may be associated with transient shifts in soil-solution chemistry that are reflected in the shells as short-term excursions. The frequency of trace-element excursions broadly matches the counts of rainfall occurrence, suggesting a possible link between shell geochemistry and weather-scale hydrological variability. During a “once-in-a-millennium” rainstorm, snail shell Mg/Ca and Mn/Ca exhibited a pronounced spike and a sustained anomaly, respectively, highlighting their sensitivity to extreme events, whereas Na/Ca, Sr/Ca, and Ba/Ca show more reproducible covariation among samples and may be better suited for reconstructing the frequency of weather-scale rainfall event. These results provide preliminary evidence that trace-element in land snail shells may hold potential for tracking environmental variability at weather timescales, though the underlying mechanisms are complex and warrant further study.

Norfloxacin (NFX) is a widely used antibiotic that poses a persistent threat to aquatic ecosystems. The combination of photocatalysis and microalgae has emerged as a promising strategy for antibiotic removal. However, current research predominantly focuses on optimizing photocatalytic conditions and overall system efficiency, often neglecting the dynamic physiological state of microalgae when exposed to the photocatalytic degradation products of NFX (PDPN), which is the mixture of intermediates after 2 h ZGF photocatalysis of 8 mg/L NFX. This study constructed a synergistic degradation system employing a ZnO/g-C3N4/Fe3O4 (ZGF) composite photocatalyst and Chlorella vulgaris for PDPN removal. Within this synergistic system, our primary focus was on the microalgal activity when cultured in a medium prepared from the PDPN. The results indicated the degradation rate of PDPN reached 82.1% in the synergistic degradation system. Transcriptomic analysis revealed that microalgae exhibited enhanced adaptability to these products, which were generated from ZGF photocatalytic pre-treatment of NFX. Key functional categories, including catalytic activity, oxidoreductase activity, and cytochrome P450 drug metabolism were significantly upregulated. This study indicates that the ZGF/microalgae system simultaneously achieves efficient pollutant degradation and maintains high metabolic potential as revealed by transcriptomic profiling, providing crucial insights for developing stable and sustainable bioremediation technologies.

High-salinity nitrogenous organic industrial wastewater poses a severe threat to microbial activity due to its extreme osmolarity and complex composition, often causing catastrophic failure of biological nitrogen removal systems. This study presents a novel strategy employing AHL-based quorum sensing to systematically mitigate salinity inhibition, achieving dual enhancement of complex organic nitrogen mineralization and inorganic nitrogen removal. The AHL 3-oxo-C6-HSL was identified as the most effective compound, promoting ammonia oxidation and minimizing nitrite accumulation under salinity stress. In SBR systems, 3-oxo-C6-HSL accelerated the completion of nitrification under 5% salinity within 5 days, compared to 18 days in the control, and achieved a TN removal rate of 79.46% under 8% salinity, which was significantly higher than that of other AHLs. In the biological aerated filter, the addition of 3-oxo-C6-HSL enabled the system to maintain high stability and efficiency even at 8% salinity. This enhancement was evidenced by a 37.87% reduction in nitrite accumulation compared to the control, 99% aniline degradation within 5 days, and the concurrent removal of 95% COD and 80% TN under saline conditions. Mechanistic analysis revealed that 3-oxo-C6-HSL activated microbial quorum sensing, thereby enhancing metabolic activity and salinity-tolerant defense mechanisms. Additionally, it facilitated the formation of a denser and more stable biofilm structure. Omics analysis further revealed that AHLs significantly enriched key aniline degraders, such as Azoarcus, systematically activating multiple rate-limiting enzymes within both the aniline degradation pathway and the inorganic nitrogen conversion cycle. This research presents an innovative and efficient microbial communication strategy for the biotreatment of high-salinity, nitrogenous organic wastewater, thereby expanding the understanding of biological nitrogen removal under extreme environmental stress.

Microbial-driven nitrogen conversion directly affects the soil nutrient supply and plant growth, playing a vital role in the ecological restoration of tailings ponds. Feammox, as a novel microbial nitrogen cycle pathway, might be more active in a tailings pond environment. Four distinct soil types adjacent to an acidic mine drainage (AMD) lake in a sulfur-rich pyrite tailings area were examined: tailings dam soil, shrubland soil, agricultural soil, and pond sediment. Environmental characteristics and microbial functional responses of these soils were systematically analyzed. The high-throughput sequencing results revealed significant differences in soil microbial communities from different environments. Agricultural management and high moisture content may significantly improve soil properties and promote a positive succession of microbial communities. The qPCR analysis revealed inhibited nitrogen transformation capacity in tailings dam and shrub soils. In contrast, agricultural soil showed the highest Feammox activity. The 15N isotope tracing experiment results revealed that the Feammox rate in agricultural soil was the highest, reaching 705 μg/kg N·d. The statistical analysis results show that bioavailable Fe, TN, NH4+-N, TOC, etc., significantly affect the process of soil microbial nitrogen transformation. Among them, bioavailable Fe is the most critical factor affecting Feammox. This study provides a case for studying soil microorganisms in tailings areas, which is of great significance for studying Feammox and carrying out in situ remediation in the soil of tailings areas. Soils in tailings pond vary in environmental indicators and microbial communities Agricultural soil and pond sediment excel in Feammox, driven by Bio-Fe, TN, NH4+-N Agricultural soil has highest Feammox rate, boosted by management and moisture

Superfine iron tailings (SIT), a typical solid waste, have been recycled and reused as a raw material for 3D-printed geopolymers in previous studies. This paper proposes an integrated life cycle assessment (LCA) and techno-economic analysis (TEA) framework to evaluate the environmental and techno-economic benefits of coal fly ash (CFA) and SIT-based 3D-printed geopolymers (CS-3DPG) across different production stages, from the pumpability stage (S-I) to the buildability stage (S-II). The LCA results showed that the environmental impacts contribution in S-I was significantly higher-by 46.68% to 98.34%-than that in S-II. Scenario analysis identified the concentration of sodium silicate as the most sensitive factor influencing environmental impacts. The uncertainty analysis indicated that the production process of CS-3DPG remained low-carbon in both S-I and S-II, but increased risks in several other environmental impact categories. The contribution degree of unified environmental impacts was refined by incorporating compressive strength, yield stress, and plastic viscosity as functional units. Based on this framework, strategies were proposed to reduce the use of sodium silicate and accelerators while increasing the use of retarders, thereby lowering pollution and carbon emissions associated with CS-3DPG in S-I and S-II. TEA results indicated that the market price of CS-3DPG must exceed 73.4 USD/t to offset its levelized cost with LCA study boundary. These findings provide new research program for environmental and techno-economic sustainability of solid waste-based on 3DPG.

Uranium wastewater with complex composition from mining and processing activities challenges practical treatment. This study develops a phosphoric acid-modified biochar (P-BC) for efficient U(VI) removal from real mining wastewater. The results show that adsorption capacity of P-BC is about 500% and 3000% higher than that of pristine biochar and commercial activated carbon in batch adsorption experiment, while P-BC also shows exceptional regenerability in fixed-bed continuous adsorption experiment. This improved performance arises from both elevated porosity and chemically anchored surface phosphate moieties. Both XPS and DFT study identify these phosphate moieties as the dominant binding sites for UO22+. The adsorption mechanism is governed by strong Lewis acid–base interaction, forming stable inner-sphere P-O-U adducts. By bridging experimental results with molecular insights, this work confirms practical viability of P-BC and provides critical design guidance for advanced sorbents targeting radionuclide remediation in complex, actual wastewater.

In redoximorphic soils and sediments, cadmium (Cd) fate is governed by Fe(II)-induced transformation of metastable iron oxides. Lepidocrocite (Lep), a ubiquitous intermediate in such environments, commonly exhibits plate-like (P-Lep) or rod-like (R-Lep) morphologies with distinct exposed facet ratios and crystallinity. These structural variations engender differential Fe(II) adsorption affinities and electron transfer capacities, thereby influencing mineralogical transformation pathways and associated Cd redistribution. Herein, we investigated the transformation of Cd-adsorbed P-Lep and R-Lep under Fe(II) concentrations of 0.2-5.0 mM using synchrotron radiation X-ray diffraction, Mössbauer spectroscopy, high-resolution transmission electron microscopy and Cd speciation extraction. At 0.2-1.0 mM Fe(II), R-Lep readily transformed into magnetite due to its enhanced Fe(II) adsorption affinity, whereas at 2.0-5.0 mM, P-Lep exhibited preferential transformation arising from its superior electron transfer capacity. Mineralogical analysis revealed that P-Lep and R-Lep transformed into magnetite primarily through dissolution-reprecipitation and topotactic transformation, respectively. Notably, magnetite formed via topotactic transformation exhibited superior Cd immobilization capacity, whereas the homoepitaxial growth of Lep facilitated Cd migration. These findings provide a mechanistic foundation for predicting Cd mobility in redox-fluctuating environments, facilitating targeted remediation strategies utilizing iron oxides.

Iron ore tailings (IOT), as a bulk industrial solid waste, are in urgent need of resource utilization. Iron ore tailings-based inorganic insulation boards (IOT-IIB) were fabricated via a synergistic approach involving sodium silicate alkali activation and hydrogen peroxide (H2O2) foaming at room temperature, with lithium feldspar powder (LFP) used as an additive. The effects of LFP, foaming agent H2O2, cationic surfactant cetyltrimethylammonium bromide (CTAB), and thickener sodium carboxymethyl cellulose (CMC) on the thermalmechanical properties of IOT-IIB were significant. The optimal formulation for preparing IOT-IIB was determined as follows: CMC content of 0.6%, H2O2 content of 6%, CTAB content of 0.8%, and LFP content of 40%. The resulting IOT-IIB exhibited a dry density of 240.67 kg/m3, a compressive strength of 0.68 MPa, and a thermal conductivity of 0.090 W/(m & sdot;K). The formation mechanism of IOT-IIB involves three stages: In the geopolymerization stage, silicon and aluminum components dissolve and polymerize to form a three-dimensional network; In the foaming stage, a uniform porous structure is generated; In the curing stage, unreacted raw materials continue to polymerize and fill the pores. This study provides theoretical guidance for the resource utilization of IOT in the field of inorganic insulation boards.

Soil covering is widely applied in mine-site restoration to suppress sulfide oxidation by limiting oxygen diffusion and promoting the enrichment of sulfate-reducing bacteria. However, increasing evidence indicates that acidification can recur beneath soil covers, raising concerns about the long-term stability of restored mine sites. In this study, we combined geochemical profiling with microbial community and ecological assembly analyses to investigate the processes associated with subsurface acidification in soil-covered waste dumps. Our results show that, despite initial lime neutralization, strong acidity re-emerged in amended layers within two years (pH < 4), accompanied by elevated metal (loid) bioavailability and upward acid migration. These geochemical changes were associated with a restructuring of the microbial community toward acidophilic taxa, including Sulfobacillus and Acidithiobacillus, and an increased representation of sulfur-related metabolic potentials inferred from functional prediction. Null model and network analyses further revealed a shift toward more deterministic community assembly and tightly connected microbial networks under low-pH conditions. Together, these findings suggest that subsurface acidification beneath soil covers is sustained by coupled geochemical processes and a specialized acidophilic microbiome. This study provides insight into the mechanistic underlying soil-cover restoration failure and highlights the need for restoration strategies that integrate long-term geochemical control with microbial process management.

Abstract Effective co-immobilization of arsenic (As) and antimony (Sb) in contaminated paddy soils remains a persistent challenge for conventional biochar amendments. To address this limitation, a magnetic biochar gel (FeRBG) was synthesized by integrating rice husk biochar, iron oxides, and graphene into a three-dimensional porous network. Its remediation performance and ecological effects were systematically evaluated in Sb-As co-contaminated soil-rice systems. Compared to pristine and Fe-modified biochar, FeRBG decreased (NH4)H2PO4-extractable Sb and As concentrations more significantly, by 23.1% and 22.3%, respectively, primarily by reducing non-specifically adsorbed fractions and promoting transformation into residual phases. Notably, FeRBG was the only amendment that significantly decreased Sb and As accumulation in rice grains by 16.1% and 34.0%, respectively, compared to the control. Furthermore, FeRBG enhanced root system architecture, increasing total root length, surface area, mean diameter, and tip number. Biochar amendment reshaped soil bacterial communities, with core taxa including Pirellulaceae, Nitrosomonadaceae, Sphingomonadaceae, and Comamonadaceae. Redundancy and correlation analyses revealed that soil Sb/As availability and Fe content were key environmental factors regulating bacterial community succession. Structural equation modeling revealed that FeRBG enhanced metalloid immobilization through Fe–O–Sb/As complexation, thus reducing grain accumulation and increasing rice yield. These findings provide a competitive functionalized biochar strategy for the sustainable remediation of Sb/As co-contaminated paddy soils and for improving rice cultivation.