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A monolithic adsorbent was designed aiming to the structure of osthole and columbianadin, and fabricated using diallyl phthalate as the monomer and ethylene dimethacrylate as the crosslinker with the addition of bamboo biochar, via polymerization reaction in a stainless-steel tube. The prepared composite adsorbent packed in the tube was used as a solid-phase extraction column for the extraction and determination of two coumarins (osthole and columbianadin) in Angelicae Pubescentis Radix, combing with a C18 analytical column through an HPLC instrument, which show excellent matrix-removal ability and good selectivity to osthole and columbianadin. Furthermore, the present adsorbent shows good applicability, which was used for the extraction of osthole from Duhuo Jisheng Pill. Compared to the commercial C18 and phenyl adsorbent, the present adsorbent own better selectivity and higher resolution. These results attributed to the enhanced specific surface area (141 m2/g) and enriched interaction sites of the resulting composite adsorbent, due to the doping of bamboo biochar, which can produce hydrogen bond, dipole-dipole, π-π and hydrophobic force interactions with the osthole and columbianadin. The methodology validation indicated that the present method showed good precision and good accuracy, and the composite adsorbent showed good preparative repeatability, which can be reused for no less than 100 times with the relative standard deviation ≤4.6 % (n = 100). The present work provided a simple and efficient method for the extraction and determination osthole and columbianadin from Angelicae Pubescentis Radix.

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The reuse of arsenic (As)-contaminated paddy fields is a global challenge because long-term flooding would result in As release due to the reductive dissolution of iron minerals. Biochar amendment is a common and effective remediation technique for As-contaminated paddy soil. However, the literature is still lacking in systematic research on the function of biochar in controlling the complexation of released dissolved organic matter (DOM) and iron oxides and its synergistic impact on the availability of As in flooded paddy soil. In the present study, bamboo biochar was prepared at different pyrolysis temperatures (300, 450 and 600 °C), as BB300, BB450 and BB600. Four paddy soil treatments including BB300, BB450, BB600 applications (1% ratio, m/m, respectively) and control (CK, no biochar application) were set and incubated for 60 d in flooding condition. The results showed that As availability represented by adsorbed As species (A-As) was mitigated by BB450 amendment compared with CK. The amendment of BB450 in paddy soil facilitated the complexation of HCl extractable Fe(III)/(II) and DOM and formation of amorphous iron oxides (e.g. complexed Fe species). Moreover, the abundance of Geobacteraceae and Xanthomonadaceae, as common electroactive bacteria, was promoted in the BB450 treated paddy soil in comparison to CK, which assisted to form amorphous iron oxides. The formed amorphous iron oxides then facilitated the formation of ternary complex (As-Fe-DOM) with highly stability, which could be considered as a mechanism for As immobilization after biochar was applied to the flooding paddy soil. Thus, the synergistic effect between amorphous iron oxides and electroactive stains could make main contribution to the passivation of released As in paddy soil under long-term flooding condition. This study provided a new insight for As immobilization via regulating iron-organic ligand complexation amendment with biochar in flooding paddy soil.

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The health of agroecosystems is subsiding unremittingly, and the over-use of chemical fertilizers is one of the key reasons. It is hypothesized that integrating biochar, a carbon (C)-rich product, would be an effective approach to reducing the uses of synthetic fertilizers and securing crop productivity through improving soil properties and nutrient cycling. The bamboo biochar at different quantities (4-12 Mg ha-1) and combinations with chemical fertilizers were tested in stevia (Stevia rebaudiana) farming in silty clay acidic soil. The integration of biochar at 8 Mg ha-1 with 100% nitrogen (N), phosphorus (P), and potassium (K) produced statistically (p ≤ 0.05) higher leaf area index, dry leaf yield, and steviol glycosides yield by about 18.0-33.0, 25.8-44.9, and 20.5-59.4%, respectively, compared with the 100% NPK via improving soil physicochemical properties. Soil bulk density was reduced by 5-8% with biochar at ≥ 8 Mg ha-1, indicating the soil porosity was increased by altering the soil macrostructure. The soil pH was significantly (p ≤ 0.05) augmented with the addition of biochar alone or in the combination of N because of the alkaline nature of the used biochar (pH = 9.65). Furthermore, integrating biochar at 8 Mg ha-1 with 100% NPK increased 22.7% soil organic C compared with the sole 100% NPK. The priming effect of applied N activates soil microorganisms to mineralize the stable C. Our results satisfy the hypothesis that adding bamboo biochar would be a novel strategy for sustaining productivity by altering soil physicochemical properties.

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The study aim was to reveal the mechanism of impact of two type biochar on composting of hen manure (HM) and wheat straw (WS). Biochar derived from coconut shell and bamboo used as additives to reduce antibiotic resistant bacteria (ARB) in HM compost. The results manifested that effect of biochar amendment was significant to reduce ARB in HM composting. Compared with control, the microbial activity and abundance were increased in both biochar applied treatment, and bacterial community was changed. Additionally, network analysis revealed that biochar amendment increased the quantity of microorganisms related to organic matter degrading. Among them, coconut shell biochar (CSB) played a pioneering role to mitigate ARB to better exert its effects. Structural correlation analysis showed that CSB reduce ARB mobility and promote organic matter degradation via improving beneficial bacterial community structure. Overall, composting with participation of biochar amendment stimulated antibiotic resistance bacterial dynamics. These results evidence practical value for scientific research and lay the foundation for agricultural promotion of composting.

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It is of great significance to develop green, sustainable additives to improve the thermal stability and flame retardancy of biopolymers. In this work, a synergistic modification of P/N elements to bamboo biochar (mBC) was successfully achieved by grafting a reaction of phytic acid and urea with preoxidized bamboo biochar. Fourier transform infrared spectroscopy, X-ray diffraction, nuclear magnetic resonance and scanning electron microscope determinations of the mBC demonstrated a successive grafting of phytic acid and urea to the originally porous surface. The ground mBC was blended with polylactic acid (PLA) to prepare mBC/PLA composites by extrusion and hot pressing. Mechanical strength studies showed a compromise in rigidity, which might originate from the mBC overdose and its limited miscibility with the resin. The thermogravimetric results supported the fact that the enhancement of thermal stability and flame retardancy of the composites with the mBC dosage, which showed that the mBC dosage in the PLA composites was not only lower than that of the conventional flame retardants, but also outperformed the counterparts using BC modified by inorganic phosphoric acid and urea. The mBC was prone to accelerate the earlier decomposition of the composites (30 °C lower in decomposition) and generate a continuous, dense residual carbon layer, which provides an effective shield resisting the mass and heat transfer between the combustion area and the underlying composite matrix. Only 10 wt% of mBC dosage could achieve a V-0 rating (UL94) for the composite, with a higher limiting oxygen index up to 28.3% compared to 20.7% for that of the virgin PLA; the cone colorimetric results also suggested that the flame retardancy had been greatly improved for all composites. In this work, biobased P-/N-containing bamboo biochar would be expected as a nontoxic biochar-based flame retardant that serves as green filler in polymer composites.

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Maintaining humidification and inhibiting nitrogen losses during vermicomposting process have emerged to be key factors for high-quality productions. Previous data have showed outstanding functions of biochar addition in improving vermicomposting quality. In this study, the influence of bamboo biochar (BB) and rice husk biochar (RHB) addition on compost maturity, humification and nitrogen loss was evaluated in the vermicomposting of cattle manure and maize straw. Results revealed that BB or RHB amendment improved organic matter decomposition, enhanced humification and maturity of compost, particularly in the 10% BB treatment, which exerted the highest humic acids content and GI value. Furthermore, BB or RHB addition significantly reduced nitrogen losses, in which the volatilization of NH3 and N2O were reduced by 24.93%-66.23% and 14.91%-55.12%. The fewest nitrogen loss was detected in the treatment of 10% BB. Biochar inhibited nirK, nirS but promoted AOB-amoA, nosZ expression; fewer N2O producing bacteria (Pseudomonas, Devosia, Luteimonas genus) were observed in the biochar treatment, and thereby decreased the N2O emission. Therefore, 10% BB addition for co-vermicomposting cattle manure and maize straw is an efficient way to increase humification, maturity, and reduce nitrogen loss, and future applications following this strategy is believed to generate better productions.

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Anaerobic digestion is considered an environmentally benign process for the recycling of food waste into biogas. However, unscientific disposal of ammonium-rich food waste digestate (FWD), a by-product of anaerobic digestion induces environmental issues such as odor nuisances, water pollution, phytotoxicity and pathogen transformations in soil, etc. In the present study, FWD produced from anaerobic digestion of source-separated food waste from markets and industries was used for converting FWD into biofertilizer using 20-L bench scale composters. The issues of nitrogen loss, NH3 volatilization, and greenhouse gas N2O emission were addressed using in-situ composting technologies with the aid of tobacco and bamboo biochar produced at pyrolytic temperatures of 450 °C and 600 °C, respectively. The results demonstrated that the phytotoxic nature of FWD could be reduced into a nutrient-rich compost by mitigating nitrogen loss by 29-53% using 10% tobacco and 10% bamboo biochar in comparison with the control treatment. Tobacco biochar mitigates NH3 emission by 63% but enhances the N2O emission by 65%, whereas bamboo biochar mitigates both NH3 and N2O emissions by 48% and 31%, respectively. Overall, 10% tobacco and 10% bamboo biochar amendment could reduce total nitrogen loss by 29% and 53%, respectively. Furthermore, the biochar addition significantly enhanced the biodegradation rate of FWD and the mature compost could be produced within 21 days of FWD composting as seen by an increased seed germination index (>50% on dry weight basis). The results of this study could be beneficial in developing a circular bioeconomy locally with the waste-derived substrates.

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A series of activated biochar (KBBC-700, KBBC-800 and KBBC-900) which were modified by KOH and pyrolysis at various temperatures from ball-milling bamboo powder were obtained. The physicochemical properties and pore structures of activated biochar were investigated by scanning electron microscopy (SEM), fourier transform infrared spectoscopy (FT-IR), X-ray diffraction (XRD) and N2 adsorption/desorption. The adsorption performance for the removal of methylene blue (MB) was deeply studied. The results showed that KBBC-900 obtained at activation temperature of 900 °C exhibited a great surface area which reached 562 m2/g with 0.460 cm3/g of total pore volume. The enhancement of adsorption capacity could be ascribed to the increase of surface oxygen-containing functional groups, aromatization and mesoporous channels. The adsorption capacity was up to 67.46 mg/g under the optimum adsorption parameters with 2 g/L of adsorbent dose, 11 of initial solution pH and 298 K of the reactive temperature. The adsorption capacity was 70.63% of the first time after the material was recycled for three cycles. The kinetics indicated that the adsorption equilibrium time for MB on KBBC-900 was of about 20 min with the data fitted better to the pseudo-second-order kinetics model. The adsorption process was mainly dominated by chemical adsorption. Meanwhile, the adsorption isotherm showed that the Langmuir model fitted the best, and thermodynamic parameters revealed that the adsorption reaction was the endothermic nature and the spontaneous process. Adsorption of MB mainly attributed to electrostatic interactions, cation-π electron interaction and redox reaction. This study suggested that the activated biochar obtained by KOH activation from bamboo biochar has great potentials in the practical application to remove MB from wastewater.

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The purpose of this study was to investigate antibiotic resistant fungal (ARF) communities in pig manure (PM) composting employing two different biochar (coconut shell-CSB and bamboo biochar-BB) as amendment. Three treatments (Control, 10% CSB and 10% BB) were designed and indicated with T1 to T3. Experimental results declared that the fungal abundance significantly reduced among the both biochar applied treatments but three dominant phyla Ascomycota, Basidiomycota and Mucoromycota were still relatively greater abundance present. There were significant differences (p < 0.05) in the relative abundance and diversity of fungi among all three treatments. Interestingly, biochar addition regulated the overall fungal community in final compost. Compared with the control group, the abundance of fungi was positively mobilized, and especially CSB showed a better effect. Conclusively, biochar has potential to inhibit and reduce the ARGs population and mobility in compost. Thus, these findings offer new insight to understand the succession of ARFs during PM composting.

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Increasing population, industrialization, and economic growth cause several adverse impacts on the existing environment and living being. Therefore, rising pollutants load and their mitigation strategies, as well as achieving energy requirements while reducing reliance on fossil fuels are the key areas, which needs significant consideration for sustainable environment. Since India has considerable biomass resources, bioenergy is a significant part of the country's energy policy. However, the selection of feedstock is a crucial step in bioenergy production that could produce raw material without compromising food reserve along with the sustainable environment. Higher growth capacity of bamboo species makes them a suitable lignocellulosic substrate for the production of high-value greener products such as fuels, chemicals, and biomaterials as well as an appropriate candidate for eco-restoration of degraded land. In that context, the current review discusses the multidimensional applications of bamboo species in India. The bioenergy potency of bamboo and probability of aligning its production, cultivation, and operation with economic and social development agendas are also addressed, making it an exceptional crop in India. Additionally, its fast growth, perennial root systems, and capability to restore degraded land make it an essential part of ecological restoration. Furthermore, this review explores additional benefits of bamboo plantation on the environment, economy, and society along with future research prospects.

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In present study, the taxonomic variation of antibiotic resistant bacteria (ARB) in pig manure (PM) composting with coconut shell biochar (CSB) and bamboo biochar (BB) addition was investigated. The experiment was divided into three treatments: T1 (as control or without biochar amendment), T2 was added 10% coconut shell biochar and T3 supplemented with 10% bamboo biochar. The initial feed stock were properly homogenized using a mechanical crusher. PM and wheat straw (WS) were mixed in a 5: 1 dry weight ratio to adjust the initial carbon/nitrogen ratio 25:1, bulk density to ~0.5 (kg/L) and ~60% moisture content, respectively. This experiment was lasted for 42 days. The results indicated the bacterial communities in the three treatments were more different in terms of relative abundance and diversity of dominant bacteria. The control group had the highest abundance of Kingdome bacteria. The changes in ARB was noticed by variation in the relative abundances of Actinobacteria, Proteobacteria, Firmicutes and Bacteroidota. At the end of composting (on day 42), the total RAs of ARB at the class, order, and family levels were considerably reduced in T2 and T3 by ~35.78-38.75%, 36.42-40.63% and 45.82-47.70%, respectively. But in T1 was decreased by 6.16-8.62%, 7.93-8.72% and 8.70-10.15%, as compared with the day 0 sample. However, the CSB was much more effective to reduce 55 to 60% of ARB than T3 or BB applied treatment has 40 to 42% ARB reduction, while control has certainly very less RAa of ARB reduction. Finally, the biochar amendment was significant approach to mitigate the total ARB abundance in compost and it's further used for organic farming purposes.

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The discharge of antibiotics evokes environmental health crisis, and is also a waste of organic energy. Currently, heterogeneous Fenton for antibiotics removal has attracted growing attentions due to wide pH range and no iron sludge production, however, it often suffers from a low formation rate of Fe(II), resulting in difficult application of heterogeneous Fenton technology in sewage treatment. To overcome this drawback, bamboo biochar (BB) is coupled with schwertmannite (Sch) through Acidithiobacillus ferrooxidans-mediated Fe(II) oxidation reaction to obtain a heterogeneous catalyst (Sch/BB) with high adsorption performance and Fenton activity. According to the analysis of experimental results, electrons around C (from BB) can easily transfer to Fe by Fe-O-C bonds to expedite ≡Fe(III)/≡Fe(II) cycle, while electrons of antibiotics adsorbed on Sch/BB surface are effectively utilized to maintain the efficient regeneration of ≡Fe(II) through BB electron shuttle or Fe-O-C bonds between Sch/BB and pollutants, further causing a superior Fenton activity (98% antibiotics removal) of Sch/BB. Moreover, due to its excellent adsorption performance, Sch/BB as filter materials can effectively remove dye pollutants in flow wastewater. These findings provided a high-activity and practical heterogeneous Fenton catalyst for pollutants degradation, while a new perspective for efficient utilization of the electrons of organic pollutants was given.

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Biochar compound fertilisers (BCFs) are an emerging technology that combine biochar with nutrients, clays and minerals and can be formulated to address specific issues in soil-plant systems. However, knowledge of BCF performance over consecutive crops and without re-application is limited. This study aims to assess the residual effect of organic BCFs soil-plant nutrient cycling 2 years after application and without additional fertiliser inputs. We applied BCFs and biochar with organic fertiliser amendments and established a crop of ginger and a second crop of turmeric (Curcuma longa) without re-application or additional fertilisation. All treatment formulations included bamboo-biochar and organic fertiliser amendments; however, two novel BCFs were formulated to promote agronomic response in an intensive cropping system. We report here on the effect of treatments on soil and plant macronutrient and micronutrient cycling and turmeric growth, biomass and yield at harvest. Both BCFs (enriched (10 t ha-1) and organo-mineral biochar (8.6 t ha-1) increased foliar K (+155% and +120%) and decreased foliar Mg (-20% and -19%) concentration compared with all other treatments, suggesting antagonism between K and Mg. Plants were limited for K, P and B at harvest but not N, Ca or Mg. Foliar K was dependent on the biochar formulation rather than the rate of application. Biochar-clay aggregates increased K retention and cycling in the soil solution 2 years after application. Clay blended BCFs reduced K limitation in turmeric compared to biochar co-applied with organic amendments, suggesting these blends can be used to manage organic K nutrition. All formulations and rates of biochar increased leaf biomass and shoot-to-root ratio. Novel BCFs should be considered as an alternative to co-applying biochar with organic fertiliser amendments to decrease application rates and increase economic feasibility for farmers. Applying BCFs without re-application or supplementary fertiliser did not provide sufficient K or P reserves in the second year for consecutive cropping. Therefore, supplementary fertilisation is recommended to avoid nutrient deficiency and reduced yield for consecutive organic rhizome crops.

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At present, the simultaneous removal of organic dyes and heavy metals in complex wastewater has raised considerable concern, owing to their striking differences in physicochemical properties. Adsorption, as one of the few removal methods, has attracted extensive attention and gained popularity. Herein, a versatile EDTA and chitosan bi-functionalized magnetic bamboo biochar adsorbent (ECMBB) was synthesized for coinstantaneous adsorption of methyl orange (MO) and heavy metals (Cd(II) and Zn(II)). In this case, the as-synthesized ECMBB composites inherited favorable anionic MO removal performance from bamboo biochar (BB) obtained at 700 °C through electrostatic attraction, hydrogen bonding and π-π interaction, also enhanced the binding of cationic metals by introducing amino groups of chitosan and carboxyl groups of EDTA. In the unitary system, the removal of MO, Cd(II) and Zn(II) by three as-prepared adsorbents can be well illuminated by pseudo-second-order kinetic model and Langmuir isotherm theory. The saturated capture amounts of ECMBB at 25 °C are 305.4 mg g-1 for MO, 63.2 mg g-1 for Cd(II) and 50.8 mg g-1 for Zn(II), which, under the same conditions, are 1.3, 2.6 and 2.5 times those of chitosan-modified magnetic bamboo biochar (CMBB) and 1.9, 6.1 and 5.4 times those of magnetic bamboo biochar (MBB), respectively. Remarkably, in MO-metal binary system, coexisting MO visibly enhanced the adsorption of Cd(II) and Zn(II), while coexisting heavy metals had no significant impact on MO adsorption. Furthermore, ECMBB exhibited no significant loss in adsorption efficiency even after eight adsorption-desorption experiments. This study lays the foundation for fabricating desired integrative biochar adsorbents in the simultaneous purification of organic and metallic pollutants from complex wastewater.

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Soil fungi play a vital role in soil nutrient dynamics, but knowledge of their diversity and community composition in response to biochar addition into red soil is either limited or inconsistent. Therefore, we determined the impact of bamboo biochar (BB) with increasing concentrations (0, 5, 20, and 80 g kg-1 of soil, referred to as B0, BB5, BB20, and BB80, respectively) on soil physicochemical properties and fungal communities (Illumina high-throughput sequencing) in red soil under Fokenia hodginsii (Fujian cypress). We found that increasing BB levels effectively raised the soil pH and soil nutrients, particularly under BB80. BB addition significantly increased the relative abundance of important genera, i.e., Basidiomycota, Mucoromycota, and Chytridiomycota that could play a key role in ecological functioning, e.g., wood degradation and litter decomposition, improvement in plant nutrients uptake, and resistance to several abiotic stress factors. Soil amended with BB exhibited a substantial ability to increase the fungal richness and diversity; BB80 > BB20 > BB5 > B0. Basidiomycota, Mucoromycota, Glomeromycota, Rozellomycota, Aphelidiomycota, Kickxellomycota, and Planctomycetes were positively associated with soil pH, total nitrogen, phosphorous, and carbon, and available potassium and phosphorous. Besides, the correlation analysis between the soil fungal communities and soil properties also showed that soil pH was the most influential factor in shaping the soil fungal communities in the red soil. These findings have significant implications for a comprehensive understanding of how to ameliorate acidic soils with BB addition, as well as for future research on sustainable forest management, which might increase soil fungi richness, diversity, and functionality in acidic soils.

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Wheat is the second most important food crop worldwide, which is prone to accumulate cadmium (Cd). Accumulation of Cd in wheat grains depends not only on wheat genotype, but also largely on the availability of soil Cd and its internal distribution. In this study, several experiments were used to achieve low-grain Cd content: a field trial for wheat genotype screening, a soil incubation experiment to test passivation effect of bamboo biochar on soil Cd, and a soil pot experiment to examine bamboo biochar effect on wheat grain accumulation. The results showed that of the 243 wheat cultivars tested, the variation range of grain Cd content was 0.365-1.243 mg/kg, in a field with soil Cd of 3 mg/kg. The application of bamboo biochar reduced soil Cd availability, among which 5.0% bamboo biochar treatment had the greatest effect. The content of available Cd in soil treated with 5.0% bamboo biochar decreased by 0.32 mg/kg compared with the control in a 120-day incubation experiment. Effect of bamboo biochar (0, 0.1%, 1.0%, and 5.0%) on reducing grain Cd content in two wheat genotypes (Mianyou-1 and 1279-9) was investigated. The application of bamboo biochar decreased Cd uptake by plants, while distribution of Cd in different wheat plant parts was more controlled by the plant genetic characteristics. Compared with the control, Cd content in roots, straw, and grains was decreased by 34.06% (P < 0.05), 21.57%, and 23.33%, respectively, in low-grain Cd wheat cultivar 1279-9 by 5% bamboo biochar application. Overall, the combination of low-grain Cd accumulation wheat and bamboo biochar may be a feasible strategy to lessen grain Cd accumulation in Cd-contaminated soils.

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To investigate the emission mechanism of ammonia (NH3) and nitrous oxide (N2O) during aerobic composting and the influence of powder bamboo biochar (PBB) on this process, this paper conducted a systematic study on the nitrogen-transforming functional microbial community, including functional genes, microbial structure and metabolism pathways. PBB reduced N2O and NH3 emissions by 1.25%-8.72% and 10.4%-11.8%, respectively. The quantitative PCR results indicated that the reduced N2O emission by PBB were mainly related to denitrifying genes (nirS, nirK, nosZ, and narG). The metagenome results demonstrated that Nitrosococcus was the main genus that could oxidize ammonia to nitrite decreased by PBB. The PBB significantly affected the nitrogen metabolism pathway, reduced the activity of glutamate dehydrogenase to inhibit the formation of NH4+ to reduce NH3 emission. The higher N2O emission in the control group was also related to the higher relative contents of hydroxylamine reductase and nitrite reductase.

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We investigated the effects of bamboo biochar (BBC) as soil amendment on growth and phytoremediation potential of Salix psammophila in soil heavily polluted by Cd and Zn. Bamboo biochar was added to soil at ratios ranging from 1 to 7% (w/w), which significantly increased the organic matter, available potassium (K) content, while decreased the hydrolyzable nitrogen (N) content and the levels of total and bioavailable HMs in soil. The BBC amendment at ratios of 1% to 5% showed little effect on growth of plant, whereas at 7% ratio significantly decreased biomass compared to the control. BBC amendment stimulated the accumulation of Cu, Cd and Zn in plant tissues, meanwhile, Cd and Zn accumulation were more evident, especially in the BBC-3% treatment. BBC amendment improved the TF and BCF values of Cd, Zn and Cu compared to control. Higher BCF for Cd (BCF >1) and TF for Zn (TF >1) values indicate Salix psammophila have considerable potential for phytoremediation efficiency in BBC amended soil treatment. This study provides practical evidence of the efficient BBC-assisted phytoremediation capability of Salix psammophila and highlights its potential as a viable and inexpensive approach for in situ remediation.

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Biochar shows great potential in soil remediation. The benefits of biochar on soil depend onits intrinsic properties and soil characteristics. However, the influence of particle sizes of biochar on soil remediation is not clear. In a pot experiment, we evaluated the effects of bamboo biochar (BBC) particle sizes (P1 < 0.15 mm, 0.15 mm < P2 < 0.25 mm, 0.25 mm < P3 < 0.50 mm) on phytoremediation efficiency of Salix psammophila C. cultivated in multi-metal polluted soil. We added the BBC at 3% (w/w) in tested soil. Next, the BBC was thoroughly mixed with soil and weighting to the pot, and S. psammophila cuttings were planted and grown for six months in the amended soil under model growth condition.Results revealed the addition of different sizes of BBC particles affected soil quality, plant growth, and HMs accumulation in plants. All sizes of BBC treatments improved Cd and Zn accumulation, whereas plants in P2 treatment showed the greatest accumulation, increased by 52.41 and 25.55% compared with the control (1,503 and 19,928 µg·plant-1). Overall, the results indicated BBC enhanced the phytoremediation efficiency of S. psammophila. Plants cultivated in P2 treatment showed the most significant effect on remediating contaminated soil.

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Commercialization of novel adsorbents technology for providing safe drinking water must consider scale-up methodological approaches to bridge the gap between laboratory and industrial applications. These imply complex matrix analysis and large-scale experiment designs. Arsenic concentrations up to 200-fold higher (2000 µg/L) than the WHO safe drinking limit (10 µg/L) have been reported in Latin American drinking waters. In this work, biochar was developed from a single, readily available, and taxonomically identified woody bamboo species, Guadua chacoensis. Raw biochar (BC) from slow pyrolysis (700 °C for 1 h) and its analog containing chemically precipitated Fe3O4 nanoparticles (BC-Fe) were produced. BC-Fe performed well in fixed-bed column sorption. Predicted model capacities ranged from 8.2 to 7.5 mg/g and were not affected by pH 5-9 shift. The effect of competing matrix chemicals including sulfate, phosphate, nitrate, chloride, acetate, dichromate, carbonate, fluoride, selenate, and molybdate ions (each at 0.01 mM, 0.1 mM and 1 mM) was evaluated. Fe3O4 enhanced the adsorption of arsenate as well as phosphate, molybdate, dichromate and selenate. With the exception of nitrate, individually competing ions at low concentration (0.01 mM) did not significantly inhibit As(V) sorption onto BC-Fe. The presence of ten different ions in low concentrations (0.01 mM) did not exert much influence and BC-Fe's preference for arsenate, and removal remained above 90%. The batch and column BC and BC-Fe adsorption capacities and their ability to provide safe drinking water were evaluated using a naturally contaminated tap water (165 ± 5 µg/L As). A 960 mL volume (203.8 Bed Volumes) of As-free drinking water was collected from a 1 g BC-Fe fixed bed. Adsorbent regeneration was attempted with (NH4)2SO4, KOH, or K3PO4 (1 M) strippers. Potassium phosphate performed the best for BC-Fe regeneration. Safe disposal options for the exhausted adsorbents are proposed. Adsorbents and their As-laden analogues (from single and multi-component mixtures) were characterized using high resolution XPS and possible competitive interactions and adsorption pathways and attractive interactions were proposed including electrostatic attractions, hydrogen bonding and weak chemisorption to BC phenolics. Stoichiometric precipitation of metal (Mg, Ca and Fe) oxyanion (phosphate, molybdate, selenate and chromate) insoluble compounds is considered. The use of a packed BC-Fe cartridge to provide As-free drinking water is presented for potential commercial use. BC-Fe is an environmentally friendly and potentially cost-effective adsorbent to provide arsenic-free household water.

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