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The continuous development of sustainable food-active packaging materials and practices with high performance is a response to the increasing challenges posed by microbial food safety and environmental contamination. In this study, a multifunctional bio-nanocomposite composed primarily of chitosan, cellulose nanomaterials and carvacrol was proposed as a conformal coating for fruit preservation. The coating exhibits excellent antioxidant and antibacterial activities owing to the incorporation of the carvacrol. The inhibition rate of the coating on E. coli and S. aureus is enhanced by 57.13 % and 62.18 %, respectively. And its antioxidant activities is also improved by 77.45 %. In addition, the oxygen permeability (OP) and water vapor permeability (WVP) of this CS/CNC coating are significantly lowered by 67 % and 46 %, respectively, comparing with the CS coating. The coating exhibited excellent biosafety and cytocompatibility because of over 90 % of the HepG2 cells remained alive in each concentration of the coating after 24 h incubation. Additionally, the efficacy of the coating in prolonging the freshness and visual appeal of perishable fruits is substantiated by the experiment involving two fruit specimens. Furthermore, the coating's ease of production, ingestibility, washability, and utilization of cost-effective and easily accessible biomaterials, including renewable waste materials, indicate its potential as a viable economic substitute for commercially accessible fruit coatings. [ABSTRACT FROM AUTHOR]

It is of great significance to develop natural renewable polymer materials for different applications. Herein, the nano-sized hexagonal boron nitride nanosheets (hBNNSs) were facilely exfoliated through liquid-nitrogen, microwave, and ultrasonication treatments, and novel chitosan/hBNNSs (CS/hBNNSs) films were fabricated via solution casting. The obtained transparent CS/hBNNSs films demonstrated outstanding UV shielding ability with 98.51 % UV-A and 96.40 % UV-B lights being resisted. Compared to those properties of CS film, the oxygen permeability (OP) and carbon dioxide permeability (CO 2 P) of CS/hBNNSs films are significantly lowered by 96.35 % and 94.06 %, respectively, which are much better than CS/graphene oxide or other CS nanocomposite films. Moreover, the addition of hBNNSs in CS films also obviously improves their water vapor barrier ability, thermostability, mechanical properties, and antibacterial activity. The CS/hBNNSs films and the strategy developed in this work prove their great prospect in producing high-performance packaging films with desirable excellent UV shielding and oxygen barrier qualities. [Display omitted] • Novel CS/hBNNSs nanocomposite films were facilely fabricated via solution casting. • The transparent CS/hBNNSs films could block 98.51 % UV-A and 96.40 % UV-B lights. • The OP and CO 2 P of CS/hBNNSs films are lowered by 96.35 % and 94.06 %, respectively. • The CS/hBNNSs films showed improved thermostability and mechanical properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • We report a novel ternary nanocomposite hydrogel based on the CMCS, GO and gelatin. • CMCS-GO-Gelatin hydrogel exhibited excellent physical and chemical properties. • CMCS-GO-Gelatin hydrogel exhibited outstanding in vitro drug release property. Hydrogels have received immense interest for various biomedical applications owing to their hydrated environment and outstanding properties. However, challenges still exist regarding utilizing hydrogels in the application of drug delivery and release, because of the lack of controllability, actuation and quick-response properties. Here, the functionalized carboxymethyl chitosan-graphene oxide-gelatin composite hydrogel with excellent swelling property, high biocompatibility and drug delivery efficiency was prepared by ionic crosslinking. Our study found that the carboxymethyl chitosan-graphene oxide-gelatin composite hydrogel exhibited porous structures and the pores distribute randomly but arrange regularly in the cross section. In addition, the thermal stability and excellent swelling ratio of the carboxymethyl chitosan-graphene oxide-gelatin composite hydrogel were improved. As a consequence, the CMCS-GO-Gelatin-3 exhibited the maximum cumulative release rate and the cumulative release amount of this composite hydrogel was 74.6 under the condition of buffer solution pH = 6.5 PBS and 89.1 under the condition of buffer solution pH = 7.4 PBS. Therefore, this composite hydrogel showed improved drug delivery efficiency and achieved drug prolonged administration to 24 h. This work highlights that carboxymethyl chitosan-graphene oxide-gelatin composite hydrogel will be a promising candidate for the applications in biomedical engineering. [ABSTRACT FROM AUTHOR]

The Fe3+-loaded NaBiO 3 was prepared for photocatalytic removal of tetracycline hydrochloride (TCH) from swine wastewater. Fe3+ greatly reduced the recombination efficiency of the photoinduced electron–hole pairs of NaBiO 3. Moreover, the TCH photocatalytic degradation rate constant of Fe3+-loaded NaBiO 3 was two-times higher than that of Vis+NaBiO 3 after 100 min of reaction. Fe-NaBiO 3 combined with PS (100 mg L−1) favored TCH (10 mg L−1) degradation rate (98.8%) at neutral pH. Moreover, the oxidation system was not inhibited by the fulvic acid, and showed a good photocatalytic stability. The superoxide radicals were the main active species involved in the catalytic degradation. [Display omitted] • A new bismuth-based material was prepared by simple ultrasonic agitation. • Vis+Fe-NaBiO 3 + PS system exhibited excellent removal rates of tetracycline hydrochloride. • The dynamic equilibrium of Fe2+/Fe3+ in the catalytic system greatly contributed to PS activation. • The strong resistance to organic interference exhibited broad prospects in actual wastewater. [ABSTRACT FROM AUTHOR]

The well-defined amphiphilic poly(ethylene glycol)-block-poly(propylene glycol) copolymer containing 1, 2, 3-triazole moiety and multiple ester bonds (PEG-click-PPG) was prepared by click reaction strategy. The PEG-click-PPG copolymer can self-assemble into spherical micelles in aqueous solution. It is found that high intensity focused ultrasound (HIFU) can open the copolymer PEG-click-PPG micelles and trigger the release of the payload in the micelle. The multiple ester bonds introduced in the junction point of the copolymer chain through click reactions were cleaved under HIFU, and leads to the disruption of the copolymer micelle and fast release of loaded cargo. The click reaction provides a convenient way to construct ultrasound responsive copolymer micelles with weak bonds. [ABSTRACT FROM AUTHOR]

In recent years, with the development of agriculture in southern Xinjiang, water and land resources shortage is increasingly prominent. Water-saving irrigation methods to efficiently use water resources and increase farmers' income have been proposed by Xinjiang Production and Construction Corps. Meanwhile, land resources and crop planting structure are adjusted and characteristic wood's fruit industry is developed. Jujube-cotton intercropping system in southern Xinjiang is a new type of agroforestry systems. It is unclear about the effect of jujube-cotton intercropping system with drip-irrigation on cotton growth and land use efficiency and the related mechanisms. This study aimed to investigate the influence of drip-irrigation quota on growth, yield and land use efficiency of cotton in jujube-cotton intercropping system. A field experiment was conducted in 2012 and 2013 using a randomized complete block design with jujube planting spacing of 1 m × 3 m, cotton planting spacing of 0.25 m × 0.60 m, and cotton and jujube spacing of 0.95 m. Drip-irrigation quota was 450 (GM-1), 750 (GM-2), and 1050 m3/hm2 (GM-3) for intercropping system and 750 m3/hm2 for cotton (CK-M) and jujube (CK-Z) monoculture. The stem height, diameter, aboveground dry matter, and yield of cotton were measured. The land equivalent ratio and system productivity index were calculated. The results showed that the cotton stem height was highest in the GM-3 among all treatments, and not significantly (P>0.05) different between GM-1 and GM-2. The changes in the stem diameter were similar with the height. The GM-3 treatment could adversely affect the cotton aboveground dry matter accumulation, but the GM-1 and GM-2 had similar role in increasing the cotton aboveground dry matter accumulation. The land equivalent ratio in the intercropping system was larger than 1, and greater than the monoculture system. For the two years of the experiment, the GM-2 treatment had the steadily highest land equivalent ratio and yield. Land use efficiency in jujube-cotton intercropping system was higher than the monoculture system. In addition, the system productivity index of GM-2 was relatively higher than the other treatments. In the intercropping system, the jujube was easily affected by irrigation amount and thereby its yield and productivity could be affected. The treatment of GM-2 could increase the production potential of jujube. The jujube-cotton intercropping system had a higher capacity to withstand market risks. In summary, the irrigation of 750 m3/hm2 had high land use efficiency and thus could be favorable to cotton growth and land use. The study suggested that optimal production capacity could be reached through reasonable irrigation in intercropping system. The results provided valuable information for the water resource use, and efficient land use in southern Xinjiang. [ABSTRACT FROM AUTHOR]

• Phosphorus (P) input and crop type cause differences in P loss via runoff. • Modified biochar reduced the runoff P concentration and loss load in all cropping systems. • Solid organic fertilizer decreased particulate P and colloidal P losses. • Biogas slurry increased the P loss in the runoff of the rice-wheat rotation system. Agricultural cropping systems involve the application of high fertilizer rates, which lead to phosphorus (P) losses via surface runoff to the aquatic environment, thereby resulting in severe eutrophication. Here, to evaluate the nutrient loss, we established three monitoring stations in Zhejiang Province, China, in each of which the crop types were double cropping rice, rice–wheat rotation, and vegetable cultivation. Field experiments were conducted with four treatments and three replications over a whole planting year. The four treatments at the same P application rate were: 1) no fertilization (control; CK), 2) chemical fertilization (CF), 3) substitution of 30 % chemical P in CF by organic P in solid sheep manure (OF) or in liquid biogas slurry (BS), and 4) substitution of 30 % chemical P in CF by organic P fertilizers (solid sheep manure or liquid biogas slurry) +1.5 t ha−1 polyacrylamide modified BC (PSB). The runoff losses of various P forms, that is, the total P, total dissolved P, particulate P, and colloidal P losses were analyzed. The total P concentration varied greatly with the crop growth stages. Compared with CF treatment, PSB treatment significantly reduced the concentration of P fractions in the runoff in all three cropping systems, while the OF treatment significantly reduced the particulate P and colloidal P concentrations by coating colloidal particles with organic carbon. However, BS treatment increased particulate P and colloidal P concentrations. Compared with CF treatment, PSB treatment reduced total P loss by 41.1 %, 29.7 %, and 37.8 % in the double cropping rice, rice–wheat, and vegetable systems, respectively. The PSB and OF treatments significantly reduced the particulate P and colloidal P losses, while BS treatment increased the loss of various P forms. Compared with the CF treatment, the PSB treatment significantly increased the available P contents by 12.7–85.4 mg kg-1, and decreased the colloidal P contents by 26.7 %–51.4 % in the soils examined. The results of the redundancy analysis confirmed that P loss via runoff was mainly caused by differences in the P inputs and crop types. The results of this study highlight the important role of PSB in reducing P loss via runoff from agricultural cropping systems. [ABSTRACT FROM AUTHOR]

• No-till coupled with straw return increased soil ortho-P and P availability. • No-till coupled with straw return facilitated to accumulate P monoester in the paddy soil. • No-till coupled with straw return increased the proportions of Ca-P and Fe-P in the paddy soil. Conservation tillage is well known to reduce the loss of soil phosphorus (P). However, the effects of different conservation practices on soil P speciation are still unclear. To delineate these effects, two field experiments were conducted during 2-year rice-fallow seasons with four treatments: conventional tillage/straw harvest (CTH), conventional tillage/straw return (CTR), no-till/straw harvest (NTH), and no-till/straw return (NTR). A combination of Liquid-state 31P-NMR and P K-edge XANES was used to investigate the variations in P species present in two paddy soils. Liquid-state 31P-NMR results showed that P monoesters significantly increased under NTR, and after the 2-year rice-fallow practice, the proportion of P monoesters relative to total P in the different treatments ranked as: NTR (23.25%) > NTH (22.18%) > CTR (20.29%) > CTH (19.79%) and NTR (8.61%) > NTH (8.49%) > CTR (8.31%) > CTH (8.03%) in a loam and a clay loam soil, respectively. Orthophosphate (ortho-P) also increased over time, but with no differences among treatments for the two soil types at the end of the experiment. P K-edge XANES spectra further revealed that the relative proportions of iron oxide-bound P (Fe-P i) and calcium dihydrogen phosphate (Ca-P i) were highest in the NTR treatment, higher by 27.6% and 11.1% in a loam soil and by 10.4% and 12.7% in a clay loam soil than that in the first rice season. However, the relative proportion of aluminum oxide-bound P (Al-P i) was lower by 38.6% and 40.7% in the loam and the clay loam soil, respectively. Our results suggested that no-till coupled with straw return can significantly increase the soil pool of organic P, and that this treatment was beneficial to the conversion of inorganic P species to labile forms in rice paddy soils. This study highlights the transformational relationship between different P species in conservation tillage systems. [ABSTRACT FROM AUTHOR]

Ammonium is strongly related to eutrophication and a key control of eutrophication in aquatic systems, especially in agricultural runoff. In this study, a novel Fe–Mn binary oxide‐modified lava (FMML) granular adsorbent was synthesized for ammonium removal from aqueous solutions by co‐precipitation method. The kinetic data were described by pseudo‐second‐order kinetic model well and intraparticle diffusion had effects on ammonium adsorption. For pH between 4.0 and 10.0, the adsorption efficiency was >80%, and its optimum was recorded at pH 7.0. FMML exhibited strong ammonium adsorption selectivity under the single presence of cations like Na+, K+, Ca2+, and Mg2+. The optimum adsorbent dose and particle size were 4 g/L and 3–5 mm, respectively, for an aqueous solution containing 10 mg/L of ammonium under normal conditions (298 K and pH 7.0). Furthermore, the adsorption process was endothermic, following both the Langmuir (R2 > 0.98) and Freundlich (R2 > 0.96) models. Compared with other adsorbents, the FMML can be prepared following a simpler protocol. After 30 times of adsorption–regeneration cycle, the FMML also had a relatively high ammonium adsorption capacity; hence, we see it as a prospective adsorbent for ammonium adsorption from aqueous solutions. Practitioner points: Fe–Mn binary oxide‐modified lava with Fe/Mn ratio 3:1 was prepared using co‐precipitation method.Adsorption maximum of modified lava was 20.8 mg/g (298 K and pH 7.0).Adsorption was sensitive to changes in adsorbent dose, particle size, and pH.Inorganic cations decreased ammonium adsorption in order of Na+ > K+ > Ca2+ > Mg2+.Mechanisms for ammonium removal by FMML include diffusion, electrostatic attraction, oxidation, and complexation reaction. [ABSTRACT FROM AUTHOR]

• Transparent PBAT/PLA/hBNNSs films were fabricated via film-blowing processes. • The water vapor barrier of PBAT/PLA/hBNNSs films was enhanced by 67%. • The oxygen permeability of PBAT/PLA/hBNNSs films is lowered by 65%. • The carbon dioxide permeability of PBAT/PLA/hBNNSs films is lowered by 93%. The water vapor barrier and gas barrier properties are very important factors for biodegradable packaging films. Herein, nano-sized hexagonal boron nitride nanosheets (hBNNSs) were facilely exfoliated, and novel transparent poly(butylene adipate-co-butylene terephthalate) (PBAT)/poly(lactic acid) (PLA) films incorporated with hBNNS were developed. Compared to those properties of neat PBAT/PLA film, the water vapor barrier of PBAT/PLA/hBNNSs films was greatly enhanced by 67%. Meanwhile, the oxygen permeability (OP) and carbon dioxide permeability (CO 2 P) of CS/hBNNSs films are significantly lowered by 65% and 93%, respectively. In addition, their thermal stabilities and mechanical property are also enhanced. [ABSTRACT FROM AUTHOR]

• SiO 2 /C hollow hybrid was prepared by PAA-templated sol–gel and sintering process. • Carbon improved the adhesion of SiO 2 with the PBAT matrix. • Carbon reinforced the mechanical properties of the PBAT composite film. • There was a synergistic UV-resistant effect between SiO 2 /C and UV1130. The hollow SiO 2 /C hybrid was prepared through a combined soft-templated sol–gel approach and calcination method, and applied in poly(butylene adipate- co -terephthalate) (PBAT) film. The initial elongation at breaks and tensile strength of the PBAT film loaded 4phr SiO 2 /C hybrid were increased by 34% and 71%, respectively, compared to that containing naked SiO 2. The combination of carbon with SiO 2 mainly facilitated the homogenous dispersion and better substantial interfacial adhesion in PBAT matrix. Furthermore, a release experiment of the SiO 2 /C/1130 showed that a small amount of [3-[3-(2H-Benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxyphenyl]-1-oxopropyl]-hydroxypoly(oxo-1,2-ethanediyl) (UV1130) was absorbed by the SiO 2 /C hybrid, which could furtherly improve the dispersion of hybrid in PBAT matrix and UV resistance. The work provides a promising method to reinforce PBAT composites and prepare UV-resistant PBAT films simultaneously. [ABSTRACT FROM AUTHOR]

Biochar has the potential to provide a multitude of benefits when used in soil remediation and increasing soil organic matter enrichment. Nevertheless, the intricated, hydrophobic pores and groups weaken its water-holding capacity in dry, sandy soils in arid lands. In order to combat this issue, starch-carbon-based material (SB), sodium alginate-carbon-based material (SAB), and chitosan-carbon-based material (CB) have been successfully synthesized through the graft-polymerization of biochar (BC). A series of soil column simulations were used to scrutinize the microstructure of the carbon-based material and explore its water absorption properties and its effects on sandy soil water infiltration, water retention, and aggregation. The results indicated that SB, SAB, and CB achieved water maximum absorption rates of 155, 188, and 172 g g−1, respectively. Considering their impact on sandy soils, SB, SAB, and CB lengthened infiltration times by 1920, 3330, and 3880 min, respectively, whilst enhancing the water retention capabilities of the soil by 18%, 25%, and 23% in comparison to solely adding BC. The utilization of these innovative materials notably encouraged the formation of sandy soil aggregates ranging from 2.0 to 0.25 mm, endowing the aggregates with enhanced structural stability. Findings from potting experiments suggested that all three carbon-based materials were conducive to the growth of soybean seeds. Thus, it is evident that the carbon-based materials have been fabricated with success, and they have great potential not only to significantly augment the water retention capacities and structural robustness of sandy soils in arid areas, but also to bolster the development of soil aggregates and crop growth. These materials possess significant application potential for enhancing the quality of sandy soils in arid and semi-arid regions. Highlights: Novel carbon-based materials were prepared using biochar and biodegradable organic matter. The novel materials exhibited excellent water absorption capacity. The novel materials greatly decreased the water infiltration capacity of sandy soil. The novel materials increased the water retention capacity and aggregate size of sandy soils. [ABSTRACT FROM AUTHOR]

Evaluating the lifespan of aged biodegradable mulch films from the perspective of realistic outdoor climate conditions is a challenge. However, it is worthwhile to determine the changes in their structure and stability. In this study, a talc-filled black poly (butylene adipate-co-terephthalate)/polylactide (PBAT/PLA) biodegradable mulch film was designed and mulched with shallow overburden soil to improve the anti-weathering characteristics of winter potatoes grown in southern China. This study focused on the weather resistance properties of biodegradable talc-filled PBAT/PLA-based mulch films. After 4 months of outdoor service, the elongation at break and tensile strength of talc-filled black PBAT/PLA films remained at 360 ± 250% and 15 ± 2.5 Mpa, respectively, with the number average molecular weight decreasing by 21.4% and the gel content increasing to 10%. Combining the results of microstructure analyses, molecular weight changes, thermodynamic properties, and mechanical and structural changes due to accelerated ageing under different indoor conditions, it was concluded that the maintenance of the mechanical properties of the mulch films could be attributed to the inhibition of random chain-breaking and heavy photo-crosslinking in the plastic film system. Our results using biodegradable films based on crop growth characteristics provide an effective strategy for extending the service life of biodegradable plastics and reducing the cost of biodegradable mulch films. [ABSTRACT FROM AUTHOR]

This study aimed to develop a robust predictive model for tetracycline (TC) adsorption onto biochar (BC) by employing machine learning techniques to investigate the underlying driving factors. Four machine learning algorithms, namely Random Forest (RF), Gradient Boosting Decision Tree (GBDT), eXtreme Gradient Boosting (XGBoost) and Artificial Neural Networks (ANN), were used to model the adsorption of TC on BC using the data from 295 adsorption experiments. The analysis revealed that the RF model had the highest predictive accuracy (R2 = 0.9625) compared to ANN (R2 = 0.9410), GBDT (R2 = 0.9152), and XGBoost (R2 = 0.9592) models. This study revealed that BC with a specific surface area (S (BET)) exceeding 380 cm3·g−1 and particle sizes ranging between 2.5 and 14.0 nm displayed the greatest efficiency in TC adsorption. The TC-to-BC ratio was identified as the most influential factor affecting adsorption efficiency, with a weight of 0.595. The concentration gradient between the adsorbate and adsorbent was demonstrated to be the principal driving force behind TC adsorption by BC. A predictive model was successfully developed to estimate the sorption performance of various types of BC for TC based on their properties, thereby facilitating the selection of appropriate BC for TC wastewater treatment. [ABSTRACT FROM AUTHOR]

As the typical bio-macromolecules, cellulose and its derivates are widely studied due to the fact that they are green and renewable resources in nature. In this work, intelligent temperature-pH sensitive nanohydrogels consisting of nanocellulose, thermal responsive monomer (N-isopropylacrylamide, NIPAM), and pH responsive monomer (acrylic acid, AA; acrylamide, AM) were prepared [NFC-g-(AA/AM)]-g-NIPAM, the [NFC-g-(AA/AM)]-g-NIPAM was characterized by FTIR, scanning electron microscope (SEM), thermogravimetric analysis (TGA) and automatic gas adsorption analysis (BET). The results showed that the copolymerization of AA, AM and NIPAM were carried out successfully. The specific surface area, total pore volume, average pore diameter and thermal stability of the modified nano-cellulose were increased. In addition, the as-prepared nanohydrogels with 5-fluorouracil (5-FU) released more 5-FU at 40 °C and acidic condition compared to the room temperature and neutral pH, showing the characteristics of the temperature-PH dual response functionalization. The [NFC-g-(AA/AM)]-g-NIPAM have been proved to be the promising drug release nanohydrogels towards 5-FU, and the valuable findings might provide an idea for maximizing the potential of the nanocellulose-based nanohydrogels for the application of environmental pollution control. [Display omitted] [ABSTRACT FROM AUTHOR]

Colour patterns based on micro-nano structure have attracted enormous research interests due to unique optical switches and smart surface applications in photonic crystal, superhydrophobic surface modification, controlled adhesion, inkjet printing, biological detection, supramolecular self-assembly, anti-counterfeiting, optical device and other fields. In traditional methods, many patterns of micro-nano structure are derived from changes of refractive index or lattice parameters. Generally, the refractive index and lattice parameters of photonic crystals are processed by common solvents, salts or reactive monomers under specific electric, magnetic and stress conditions. This review focuses on the recent developments in the fabrication of micro-nano structures for patterns including styles, materials, methods and characteristics. It summarized the advantages and disadvantages of inkjet printing, angle-independent photonic crystal, self-assembled photonic crystals by magnetic field force, gravity, electric field, inverse opal photonic crystal, electron beam etching, ion beam etching, laser holographic lithography, imprinting technology and surface wrinkle technology, etc. This review will provide a summary on designing micro-nano patterns and details on patterns composed of photonic crystals by surface wrinkles technology and plasmonic micro-nano technology. In addition, colour patterns as switches are fabricated with good stability and reproducibility in anti-counterfeiting application. Finally, there will be a conclusion and an outlook on future perspectives. [ABSTRACT FROM AUTHOR]

Membrane scaling is an enormous challenge in the desalination of hypersaline water using membrane distillation (MD). In this study, vacuum membrane distillation (VMD) was employed for brackish water treatment, with an emphasis on scaling mechanisms and mitigation strategies. Four methods, including deionized water, hydrochloric acid, and acetic acid, ultrasonication, were utilized for membrane cleaning. The cleaning efficiency was assessed through a comprehensive analysis of residual foulant layers. It was determined that mineral scaling constituted the primary fouling mechanism, and a minor amount of organic fouling was present at the interface between scaling-scaling and scale-membrane. Calcium and magnesium carbonate were the primary scaling components observed in brackish water desalination, appearing as needle-like and block crystals. Notably, CaCO 3 predominantly existed as the aragonite crystal structure. Ultrasonication and deionized water demonstrated limited effectiveness due to the alkaline nature of the scaling. Conversely, the application of dynamic hydrochloric acid and acetic acid treatments resulted in a significant reduction in scaling, with acetic acid demonstrating superior efficacy in removing carbonate scaling. The results presented in this study can provide valuable theoretical guidance for the treatment of brackish water using membrane desalination techniques. • Fouling mechanism of VMD in brackish water treatment was revealed. • Aragonite was the leading crystal polymorph for scaling. • Acetic acid demonstrates promise for carbonate scaling mitigation. [ABSTRACT FROM AUTHOR]

Soil water-dispersible colloidal phosphorus (WCP) presents high mobility, however, the regulatory effect of biochar-coupled organic fertilizer is rarely known, especially under different cropping patterns. This study investigated the P adsorption, soil aggregate stability, and WCP in three paddy and three vegetable fields. These soils were amended with different fertilizers (chemical fertilizer, CF; substitution of solid-sheep manure or liquid-biogas slurry organic fertilizer, SOF/LOF; substitution of biochar-coupled organic fertilizers, BSOF/BLOF). Results presented that the LOF averagely increased the WCP contents by 50.2% across the sites, but the SOF and BSOF/BLOF averagely decreased their contents by 38.5% and 50.7% in comparison with the CF. The WCP decline in the BSOF/BLOF-amended soils was mainly attributed to the intensive P adsorption capacity and soil aggregate stability. The BSOF/BLOF increased the amorphous Fe and Al contents in the fields in comparison with the CF, which improved the adsorption capacity of soil particles, further improving the maximum absorbed P (Q max) and reducing the dissolved organic matter (DOC), leading to the improvement of > 2 mm water-stable aggregate (WSA >2mm) and subsequent WCP decrease. This was proved by the remarkable negative associations between the WCP and Q max (R2 = 0.78, p < 0.01) and WSA >2mm (R2 = 0.74, p < 0.01). This study manifests that biochar-coupled organic fertilizer could effectively reduce soil WCP content via the improvement of P adsorption and aggregate stability. [Display omitted] • Biochar addition decreased soil water–dispersible colloidal P content. • Biochar addition increased soil P adsorption capacity. • Biochar addition improved soil aggregate stability. [ABSTRACT FROM AUTHOR]

As an environmentally friendly biodegradable material, poly(butylene adipate-co-terephthalate) (PBAT) has been commercialized as a shopping bag, but its high gas permeability weaken its practicability in mulch, cling film and other fields. Two kinds of barrier materials, poly(propylene carbonate) (PPC) and organically modified montmorillonite (OMt), are used to prepare PBAT/PPC/OMt composites, and the mechanical properties are improved by chain extender (Joncryl® ADR 4468). The dispersion and arrangement of nanomaterials in blends are studied with different molding methods and their effects on the gas barrier and mechanical properties are studied as well. Dissipative particle dynamics are used to simulate the rate at which O 2 molecules pass through the modified PBAT films. The results show that 1 wt% of chain extender can increase the tensile stress and tear strength by about 10% and 15%, respectively. The OMt is preferentially distributed in the PBAT matrix and has a more uniform degree of orientation in the blown film, which is beneficial to the improvement of gas barrier properties. Eventually, the mechanical properties and gas permeability of PBAT films can be regulated through the adjustment of processing methods and the synergistic effect of PPC and OMt, providing a new way for high-performance packaging or agricultural mulching film materials. • OMt was observed to be preferentially dispersed in the PBAT phase in the PBAT/PPC blends. • Prediction of selective dispersion of nanomaterials by wetting coefficient. • The gas barrier properties of blow molding films are higher than those of hot-pressed sheets by more than 20%. • Dissipative particle dynamics assisted the gas barrier effect analysis of the clay platelets in composites. [ABSTRACT FROM AUTHOR]

Phosphorus (P) availability and loss risk are linked to P species; however, their alternations in the soil amended with biochar-blended organic fertilizer is not well known, particularly under contrasting soil properties and land management. In this study, the variance of soil P species extracted by sequential chemical extraction (SCE) and 31P NMR techniques, as well as the degree of P saturation (DPS), were investigated throughout three paddy and three vegetable fields. These fields were amended with three different fertilizers at the same P application rate: chemical fertilizer (CF), organic fertilizer substitution (sheep manure/biogas slurry, SM/BS), and biochar-blended organic fertilizer substitution (BSM/BBS). Results showed that the BSM/BBS and SM increased the total P contents by 7.5% and 5.9% (TP) and available P contents by 30.1% and 19.2% (AP), but decreased the DPS values by 19.4% and 11.7%, compared to the CF treatment. Yet, the BS decreased the TP and AP contents but increased the DPS values across the experimental sites. In the BSM/BBS amended soils, high AP contents were due to the increased inorganic P (NaHCO 3 -P i), while the increased organic P (monoester and DNA) induced low DPS values and reduced soil P loss risk. Our study highlights that biochar-blended organic fertilizer is an effective agronomic way for improving P availability and decreasing P loss risk via the alteration of soil P species. [Display omitted] • High proportion of organic P and low P loss risk in the paddy fields. • Biochar addition increased stable P dissolution and organic P retention. • Biochar addition improved soil P availability and retention. [ABSTRACT FROM AUTHOR]

Colloidal phosphorus (P coll) in paddy soils can pose a serious threat to the water environment. Biochar amendment not only directly absorb P coll to reduce the runoff loss, but also create hotspots for microbial communities which simultaneously affects soil P coll. However, despite the crucial role of microorganisms, it remains elusive regarding how biochar and its feedstock types affect the relationships of soil microbial communities and P coll in soil matrix (such as at soil aggregate level). To address the knowledge gap, we explored the (in)direct effects of biochar on the soil P coll in physically separated fractions including micro- (53–250 μm) and macroaggregates (250–2000 μm). Results showed that straw and manure biochars decreased the soil P coll content by 55.2–56.7% in microaggregates and 41.2–48.4% in macroaggregates after 120 days of incubation, compared to the respective control. The fungal communities showed a significantly correlation (0.34, p < 0.05) with P coll content in the macroaggregates, whereas the bacterial communities were extremely significantly correlated (0.66, p < 0.001) with P coll content in the microaggregates. Furthermore, the partial least squares path model analysis indicated that biochar amendments directly increased P coll content (0.76 and 0.61) in micro- and macroaggregates, but the reduced P coll content by biochar was mainly derived from indirect effects, such as changed soil biological characteristics carbon (C)/P (−0.69), microbial biomass C (−0.63), microbial biomass P (−0.68), keystone taxa Proteobacteria (−0.63), and Ascomycota (−0.59), particularly for the macroaggregates. This study highlights that to some extent, biochar addition can reduce soil P coll content by affecting microbial communities (some keystone taxa), and soil biological characteristics at soil aggregate level. [Display omitted] • Biochar reduced P coll content by 41.2–56.7% in micro- and macroaggregates. • Soil P coll has a negative response to Proteobacteria and Ascomycota in aggregates. • Biochar reduced soil P coll content via altering soil biological characteristics. [ABSTRACT FROM AUTHOR]

The agricultural use of manure fertilizer increases the phosphorus (P) saturation of soils and the risk of colloidal P (P coll) release to aquatic ecosystems. Two experiments were conducted to identify whether Pteris vittata plantation can decrease P coll contents in two soils (Cambisol and Anthrosol) amended with various manure P rates (0, 10, 25, and 50 mg P kg−1 of soil). The total P coll contents in manured soil without P. vittata were 1.14–3.37 mg kg−1 (Cambisol), and 0.01–2.83 mg kg−1 (Anthrosol) across manure-P rates. The corresponding values with P. vittata were 0.97–2.33 mg kg−1 (Cambisol) and 0.005–1.6 mg kg−1 (Anthrosol). Experimentally determined colloidal minerals (Fe, Al, Ca), colloidal total organic carbon, Mehlich−3 nutrients (Fe, Al, and Ca), and the degree of P saturation were good predictors of P coll concentrations in both soils with and without P. vittata plantation. In unplanted soils, P adsorption decreased and the degree of P saturation increased which released more P coll. However, P. vittata plantation decreased the P coll release and P loss risk due to the increase of P adsorption and reduced DPS in both soils. The P fractions (NaOH, NH 4 F, and HCl–P) contributed to increase the P pool in planted soils which enhanced the bioavailability of P coll and increased the P. vittata biomass. It suggested that P. vittata plantation was an effective approach to reduce P coll release from manure amended soils. [Display omitted] • Soils with maximum P adsorption capacity reduce colloidal phosphorus release. • Pteris vittata plantation increase bioavailability of colloidal phosphorus. • Maximum Degree of P saturation promoted colloidal phosphorus release. [ABSTRACT FROM AUTHOR]

• Colloidal P was closely related to Olsen-P in paddy soils on a regional scale. • Cattle manure biochar amendment decreased colloidal P in paddy soils. • Cattle manure biochar amendment increased available P in paddy soils. Colloidal phosphorus (P coll) and available phosphorus (AP) are of fundamental importance in the nutrient cycle in soil solutions and subsurface drainage of ecosystems. Although many studies have been conducted on soil P loss and P availability, there remains limited focus on the relationship between P coll and AP. In this regional-scale study, soils with loam texture were collected from 63 paddy fields in southern China to explore the relationships between P coll and AP as well as other soil parameters. Subsequently, three typical paddy soils (sandy loam, silt loam, and clay loam) were incubated to study the effect of cattle manure biochar (CMB) amendment on P coll and AP at three application rates (0, 1, and 2%, w/w) for 30 d. The results showed that P coll was closely related to AP (R 2 = 0.453, P < 0.05) and pH (R 2 = 0. 487; P < 0.05) on a regional scale. In addition, clay loam soils contained higher P coll than the other soil types. The CMB amendment increased the AP by 129.0–872.0% but reduced the P coll by 9.65–22.95%, in which colloidal molybdenum-nonreactive phosphorus (MUP coll) was reduced by 7.69–34.15% and colloidal molybdenum-reactive phosphorus (MRP coll) was reduced by 5.13–22.73%. Multiple linear regression revealed that the release potentials of P coll (R2 = 0.735), MRP coll (R2 = 0.543), and MUP coll (R2 = 0.512) could be predicted by the dissolved organic carbon, total carbon, pH, and AP. Overall, this study confirmed that the application of CMB reduced the loss of P coll from paddy soils and enhanced the soil AP content. [ABSTRACT FROM AUTHOR]

We are still challenged to fully understand to what extent controlling irrigation inputs is important for limiting phosphorus (P) losses from paddy soils and how this affects the contribution of dissolved P (DP), particulate P (PP), and colloidal P (P coll) fractions in P losses. For this investigation, an internet-based smart irrigation system was developed to precisely implement different irrigation scenarios––flooding irrigation (FI) and two water-saving irrigation (WSI) scenarios of intermittent (II) and controlled irrigation (CI). A simulation experiment was conducted and the concentrations of total P (TP), DP, PP, and P coll released to floodwater (FW) and leachate (LW) were determined during a rice season after the addition of different P forms (chemical fertilizer (CP), biogas slurry (BP), and manure (MP)) at a rate of 40 kg P·ha−1. The results revealed that the CI scenario effectively decreased P losses in FW (∼51%) and LW (∼63%) with a positive WSI ratio (39.1%), while II reduced it in FW by ∼11% and in LW by ∼27% with a WSI ratio of 11.0% compared with FI. The BP and MP additions caused a higher risk of P losses than CP under FI, with lower risk under WSI. DP largely contributed to P losses (FW: 30%–71%; LW: 42%–66%); however, more PP was released to FW under II (37%–54% of TP). The P coll (FW: 5%–23% and LW: 6%–24%) was more sensitive to release at initial periods after fertilization on account PP. This work provides a promising approach to timely control irrigation inputs, which could limit P losses from paddy soil; however, there remains a need to assess and generalize our initial evidence at field scales. [Display omitted] • An internet-based irrigation approach was proposed to limit P losses from paddy soil. • The controlled irrigation scenario had a better performance for limiting P losses. • Colloidal and dissolved P were more release under flooding irrigation. • The intermittent irrigation triggered more particulate P release to floodwater. • Colloidal P was more sensitive to release at initial periods after fertilization. [ABSTRACT FROM AUTHOR]

Modified ceramsite has been widely reported as a P adsorbent in wastewater treatments; however, its performance in removing P from agricultural runoff is unclear. A new low-cost ceramsite is modified in this study applying Zn/Fe-layered double hydroxides (LDHs; CZF) to investigate its practicality in treating P-polluted agricultural runoff. The results revealed that the CZF has a theoretical maximum P-adsorption capacity of 11.2 mg-P g−1. Various factors in P-adsorption performance followed the order of pH value (−22.6) > Ca2+ (21.5) > Mg2+ (19.9) > CO 3 2− (−14.5) > SO 4 2− (−13.3) > humic acid (−10.7) > NO 3 − (−5.57) > Cl− (−2.93) > Na+ (0.32) > NH 4 + (0.19). Through iterant adsorption/regeneration, CZF cyclically reduced P concentration in agricultural runoff from 0.58 mg-P L−1 to below 0.1 mg-P L−1 under the preferred parameters of 20 g L−1 dosage, 2 h adsorption time at pH 7.2, and 1 h desorption time at pH 13.0. The treated water has low luminescence toxicity as well as low leaching risks of embedded Zn and adsorbed P in the spent CZF. Additionally, the CZF packing module significantly decreased P in agricultural runoff within four weeks. The CZF dosage and hydraulic retention time (HRT) prolonged the effective operating time (EOT) for P removal, whereas the total organic carbon (TOC) concentration had a negative impact. The cost of CZF for removing P from agricultural runoff was as low as 0.45 ¥ m−3. Overall, this research indicates that using CZF as the adsorption substrate in a ditch purification system is an effective approach for mitigating P pollution in agricultural runoff. Unlabelled Image • The theoretical maximum P adsorption capacity of CZF was 11.2 mg-P g−1. • CZF has low eco-risk in 55 iterant adsorption/regeneration in agricultural runoff. • CZF module decreased agricultural-runoff P to <0.1 mg-P L−1 in four weeks. • The cost of CZF treatment of P-polluted agricultural runoff is as low as 0.45 ¥ m−3. [ABSTRACT FROM AUTHOR]