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Retention and degradation of co-applied atrazine and fipronil was studied in laboratory constructed bio-augmented biobeds containing rice straw-compost (BM) and compost replaced with 10% rice husk ash [RHABM(10%)] or 1% wheat straw biochar [WBCBM(1%)] biomixtures. Atrazine (5000 µg, 50% WP) and fipronil (5000 µg, 0.3 G) were co-applied in 100 mL water. After 30 days, 7.31, 4.65, and 11.21 µg g−1 atrazine and 21.59, 7.41, and 37.20 µg g−1 fipronil remained undegraded in the top 3–4 cm of BM, RHABM(10%), WBCBM(1%) biobeds, respectively, suggesting that degradation of both pesticides significantly varied (p < 0.05) among the three biobeds. After 60 days 94.5%–98.3% of initially applied atrazine and 80.3%–86.9% fipronil degradation was observed. Hydroxyatrazine and sulphone were detected as the metabolites of atrazine and fipronil, respectively. Out of 5000 µg of initially applied pesticides, BM, RHABM(10%), and WBCBM(1%) biobeds accounted for 95.2%, 93.1%, and 95.2% of atrazine + hydroxyatrazine and 62.8%, 67.0%, and 71.5% of fipronil + sulphone degradation, respectively. Maximum amounts of recovered atrazine (68.8%–81.1%) and fipronil (89.8%–94.6%) were retained in the 0–5 cm sections of the biobeds. No significant effect of co-applied atrazine + fipronil was evident on the microbial parameters. This study suggested that RHA/WBC-mixed rice straw-compost biomixtures can be exploited for the detoxification of these pesticides in bio-purification systems. [ABSTRACT FROM AUTHOR]

Using KOH-modified wheat straw as the precursor, wheat straw biochar was produced through carbonization at 500 °C. Subsequently, a synthetic material containing nano-zero-valent iron (nZVI) was prepared via liquid phase reduction (nZVI-WSPC). To enhance its properties, chitosan (CTS) was used by crosslinking to form the new adsorbent named CTS@nZVI-WSPC. The impact of CTS on parameters such as mass ratio, initial pH value, and adsorbent dosage on the adsorption efficiency of Cr(VI) in solution was investigated through one-factor experiments. Isotherm adsorption and thermodynamic analysis demonstrated that the adsorption of Cr(VI) by CTS@nZVI-WSPC conforms to the Langmuir model, with a maximum adsorption capacity of 147.93 mg/g, and the adsorption process is endothermic. Kinetic analysis revealed that the adsorption process follows a pseudo-second-order kinetic model. The adsorption mechanism, as elucidated by SEM, FTIR, XPS, and XRD, suggests that the process may involve multiple mechanisms, including pore adsorption, electrostatic adsorption, chemical reduction, and surface chelation. The adsorption capacity of Cr(VI) by CTS@nZVI-WSPC remains high after five cycles. The adsorbent is simple to operate, economical, efficient, and reusable, making it a promising candidate for the treatment of Cr(VI) in water. [ABSTRACT FROM AUTHOR]

Using KOH-modified wheat straw as the precursor, wheat straw biochar was produced through carbonization at 500 °C. Subsequently, a synthetic material containing nano-zero-valent iron (nZVI) was prepared via liquid phase reduction (nZVI-WSPC). To enhance its properties, chitosan (CTS) was used by crosslinking to form the new adsorbent named CTS@nZVI-WSPC. The impact of CTS on parameters such as mass ratio, initial pH value, and adsorbent dosage on the adsorption efficiency of Cr(VI) in solution was investigated through one-factor experiments. Isotherm adsorption and thermodynamic analysis demonstrated that the adsorption of Cr(VI) by CTS@nZVI-WSPC conforms to the Langmuir model, with a maximum adsorption capacity of 147.93 mg/g, and the adsorption process is endothermic. Kinetic analysis revealed that the adsorption process follows a pseudo-second-order kinetic model. The adsorption mechanism, as elucidated by SEM, FTIR, XPS, and XRD, suggests that the process may involve multiple mechanisms, including pore adsorption, electrostatic adsorption, chemical reduction, and surface chelation. The adsorption capacity of Cr(VI) by CTS@nZVI-WSPC remains high after five cycles. The adsorbent is simple to operate, economical, efficient, and reusable, making it a promising candidate for the treatment of Cr(VI) in water.

Arid and semi-arid soils are low in organic matter and have poor fertility, making them a serious threat to crop production. Most organic amendments, such as crop residues and farmyard manure, are short lived because of rapid decomposition. Incubation and pot studies were conducted to assess the impact of wheat straw biochar (produced at 350 °C) on temporal changes in soil microbial biomass and fertility status and to evaluate the efficacy of biochar for maize production in the top layer of Typic calciargid. The incubation study compared four levels of biochar (control, 0.5, 1.0 and 2.0% on a w/w basis of soil) and two fertilizer rates, i.e., unfertilized (no NPK fertilizer) and fertilized (nitrogen, P2O5 and K2O with rates of 125, 80 and 52.5 mg kg−1 soil, respectively). After incubation, the 2.0% biochar significantly improved the soil cation exchange capacity, organic carbon and microbial biomass carbon by up to 35, 59 and 26%, respectively, while decreasing the soil pH by up to 1.5% compared to that of the control treatment. When fertilized, the 2.0% biochar improved the soil's available phosphorous, extractable potassium and total nitrogen by up to 59, 39 and 28%, respectively, compared to those of the control. The results from the pot experiment showed that using the 1% biochar with fertilizer significantly increased the maize dry biomass and grain yield by up to 57 and 72%, respectively, compared to those of the control. Additionally, the nitrogen and phosphorus recoveries from the mineral fertilizers improved significantly (up to 26 and 38%, respectively) when using the 1.0% biochar compared to those of the control. Conclusively, the addition of 1.0% biochar significantly improved maize growth and yield by enhancing nutrient recovery from mineral fertilizer and improving soil properties. [ABSTRACT FROM AUTHOR]

Purpose: Biochar has been considered as a good soil amendment for reducing soil cadmium (Cd) bioavailability and decreasing Cd uptake by rice. However, it is unclear if biochar can affect soil microelement zinc (Zn) bioavailability and its uptake by crops, particularly under field conditions. Materials and methods: The experimental field was contaminated by Cd, located in Hunan Province. Biochar was added at the proportions of 0, 10, 20, 30, and 40 t ha−1 on topsoil (0–17 cm) and then mixed before rice seedlings transplanted. Results: Increasing application rate of biochar improved the rice plant height, biomass, and soil electrical conductivity (EC). The DTPA extracted Zn (DTPA-Zn) concentration in the 0–17 cm of biochar treatments was decreased by 12.3–45.6% as compared to control. The increased EC played an important role in soil Zn immobilization. No remarkable difference was shown for DTPA-Zn concentration in the subsoil (17–29 cm) among biochar treatments. Increasing amount of biochar reduced the concentration and ratio of acid extractable Zn fraction, while increased the reducible and oxidizable fractions in the 0–17 cm. The reduction of concentration of DTPA-Zn in < 0.25-mm soil aggregates in biochar treatments was 29.0–72.2% and 54.3–87.9% respectively relative to control. The Zn concentration in rice was declined from 4.1 to 14.0% after biochar addition. The reduction of soil Zn availability and the improvement of rice growth made a greater contribution for the low accumulation in rice tissues. Conclusions: Biochar could immobilize more microelement Zn in soil and limit Zn uptake by rice. Biochar could limit the enrichment of DTPA-Zn in < 0.25-mm soil aggregates and enhance the transformation of soil acid extractable Zn into reducible and oxidizable fraction. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, biochar has been considered as an effective adsorbent and soil conditioner due to its abundant carbon and high porosity. This study applied a kind of biochar from wheat straw pyrolysis to remediate phenanthrene-contaminated water and soil. The performance of the biochar in the removal of phenanthrene was discussed by liquid phase adsorption and soil incubation experiments. Furthermore, this work explored the enhancement effect of wheat straw biochar on soil microbial numbers and soil properties. The result of liquid phase adsorption indicated, 92.2% of phenanthrene was removed after incubating 0.6 g/L of wheat straw biochar for 4 h. Pseudo-second-order kinetic model (R2 = 0.99823) and Langmuir isotherm model (R2 = 0.99577) described the removal of phenanthrene by wheat straw biochar well. In soil incubation experiment with an initial phenanthrene content of 11.2 mg/kg, 89.1% of phenanthrene was removed at biochar dosage of 12% (w/w, wheat straw biochar/soil) after 30 days of incubation. In addition, the number of soil microorganisms, soil pH and organic matter (SOM) content increased after wheat straw biochar treatment. At the dosage of 12%, soil microbial count increased to 9.8 × 108 CFU/g-soil, soil pH increased by 1.8 units and SOM increased by 8.5 folds. The addition of wheat straw biochar not only improved soil quality, but also reduced the proportion of phenanthrene components, which could provide theoretical support for the resource utilization of agricultural waste.

In this work, a novel adsorbent of aluminium/lanthanum loaded wheat straw biochar (Al-La-WSB), was prepared by using a facile approach and used for fluoride removal. The Al-La-WSB and its pristine wheat straw biochar (WSB) were characterized by scanning electronic microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray powder diffraction (XRD) methods. Batch adsorption experiments were carried out to investigate adsorbent performance, the highest removal rate was observed at pH 9, contact time of 7 h and Al-La-WSB dose of 1 g L−1. Lagergren pseudo-second-order kinetics and Langmuir isotherm model fitted the experimental data well. The maximum fluoride adsorption capacity of Al-La-WSB at different experiment temperature of 298, 308 and 318 K, was 51.28 mg g–1, 46.73 mg g–1 and 50.25 mg g–1, respectively, which was better than most reported adsorbents. The Al-La-WSB performed well over a considerable wide pH range of 3–10 and carried positive charge at pH < 4.8. The presence co-existing ions of SO42−, HCO3−, Cl− and NO3− had a minor impact on fluoride adsorption besides PO43−. Regeneration experiment results showed that the Al-La-WSB had an excellent reusability. According to the adsorbent characterization and batch adsorption experiment, the adsorption of fluoride on the Al-La-WSB was primarily a chemisorption, involving electrostatic interactions and ion exchange, which nitrate ion and hydroxyl played a major role. The results suggested that the Al-La-WSB could be a great adsorbent for removing fluoride from drinking water. [ABSTRACT FROM AUTHOR]

Wheat straw biochar (WSB) and lignite are counted as soil conditioners which used to improve soil properties and promote plant growth. Astragalus podolobus Boiss. & Hohen is a palatable species from Fabaceae family that is used for restoring of rangelands and fodder production as well as soil conservation against erosion. In this experiment, we studied the influence of WSB and lignite on soil properties and the plant traits of A. podolobus. For this purpose, the WSB and lignite were incorporated at levels of 0%, 1.25%, 2.5%, and 3.75% (w/w) in six repetitions. For this purpose, the experiment was done in pots at greenhouse condition. Data were analyzed statistically by one-way analysis of variance in SPSS21 software. The results demonstrated that WSB and lignite addition improve the soil microbial biomass (SMB) and chemical properties, e.g., electrical conductivity (EC), soil organic carbon (SOC), total N, phosphorus, and magnesium, but A. podolobus did not respond positively to these amendments. Also, lignite 3.75% (w/w) is the most effective treatment on improving soil properties. The SOC (g.kg−1) varied from 1.9 in the control to 4.6 and 6.5 by WSB and lignite at 3.75% (w/w), respectively. On the other hand, SMB (µg100gr−1 of soil) was significantly increased from 5.52 in the control to 11.5 and 11.67 by lignite and WSB 3.75% (w/w), respectively. The highest plant biomass (10.50 g) and the lowest roots dry weight (3.01 and 2.69 g) were observed in soil receiving lignite at 2.5% (w/w) and 1.25% (w/w), respectively. The amendment of WSB and lignite strongly enhance the properties of clay loam solonchak rangeland soil. It is suggested to add lignite soil conditioner at level 3.75%w/w in plantation the degraded rangelands but the response of other species must be tested to rate species that responds positively to the soil properties enhancement. [ABSTRACT FROM AUTHOR]

Biochar, as soil amendment, can control the bioavailability of heavy metals in contaminated soils and reduce the risk of transferring heavy metals to the food chain. The objective of the study was to investigate the impacts of biochar derived from various wastes (apple pruning (AB), grape pruning (GB), or wheat straw (SB)) at 0%, 2%, and 5% w/w affecting lettuce growth and lead (Pb) phytoavailability in a Pb-contaminated calcareous soil. The plants were harvested 60 days after seeding and plant dry weight, Pb concentration, transfer factor (TF), biological concentration factor of shoot and root (BCF), and soil Pb phytoavailability were measured. At the highest Pb spiking, NH4NO3-extractable Pb was reduced by 24.6% and 51.8% at biochar rates of 2% and 5%, respectively, compared to the control. Application of biochar decreased Pb concentration in lettuce shoots, with the most significant reduction occurring by 5% of AB (44.0%), GB (30.5%), and SB (23.8%) at the highest level of Pb. The present findings provide novel evidence on the beneficial effects of the tested biochars, especially SB, on lettuce growth in a Pb-contaminated calcareous soil. Biochars could be used as an eco-friendly and cost-effective strategy for improving lettuce growth in metal-contaminated soils. [ABSTRACT FROM AUTHOR]

Metal mining and smelting activities can introduce a substantial amount of potentially toxic elements (PTE) into the environment that can persist for an extended period. That can limit the productivity of the land and creates dangerous effects on ecosystem services. The effectiveness of wheat straw biochar to immobilize Cd in contaminated soil due to metal smelting activities was investigated in this study. The biochar carbon stability and long-term provisioning of services depend on the biochar production conditions, nature of the feedstock, and the biotic and abiotic environmental conditions in which the biochar is being used. Within this context, three types of wheat straw biochar were produced using a screw reactor at 400 °C, 500 °C, and 600 °C and tested in a laboratory incubation study. Soil was amended with 2 wt% of biochar. Both fresh and aged forms of biochar were used. Biochars produced at lower temperatures were characterized by lower pH, a lower amount of stable C, and higher amounts of acidic surface functional groups than the freshly produced biochars at higher production temperatures. At the end of the 6 months of incubation time, compared to the soil only treatment, fresh and aged forms of wheat straw biochar produced at 600 °C reduced the Cd concentration in soil pore water by 22% and 15%, respectively. Our results showed that the aged forms of biochar produced at higher production temperatures (500 °C and 600 °C) immobilized Cd more efficiently than the aged forms of lower temperature biochar (400 °C). The findings of this study provide insights to choose the production parameters in wheat straw biochar production while considering their aging effect to achieve successful stabilization of Cd in contaminated soils. [ABSTRACT FROM AUTHOR]

The co-application of biochar and fertiliser has emerged as a strategy for improving soil quality and crop growth; however, the impact of the type of fertiliser added with biochar to the soil on leaching and retention of nutrients is not well studied. In this study, a leaching experiment was undertaken using a series of column lysimeters incorporating a wheat straw biochar (WSB) and two fertiliser types—chemical fertiliser (CF), or rock mineral fertiliser (MF). The results showed that CF and MF leached a similar amount of NH4+ with or without WSB, but the NO3– leaching occurred from CF-treated soil which was decreased by CF + WSB application. In contrast, NO3– leaching was not affected by WSB in MF-treated soil. Both CF and MF with or without WSB increased the cumulative leaching of P and K. Nevertheless, WSB application increased soil P and K contents after leaching, which was attributed to intrinsic nutrient release from biochar. Shoot growth and P and K uptake also increased with biochar amendment, whereas root growth and N uptake did not change. Therefore, the results highlight that biochar addition can improve nutrient retention and plant growth by reducing nutrient leaching, mainly dependent on biochar and fertiliser type combination used. It suggests that the adsorption properties of biochar for nutrient retention and subsequent release need to know before their broad application to soils as amendments.

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Highlights • Wheat straw biochar addition effectively influence the fungal dynamic. • Fungal diversity analogous but relative abundance distinct variable during compost. • Batrachochytrium was potential host fungal genus in poultry manure compost. • Fungal and environmental elements interactions determined via Heat map illustrator. Abstract The fungal dynamics and its correlation with physicochemical and gaseous emission were investigated using metagenomics and Heat map illustrator (HEMI). Five different concentrations of wheat straw biochar (WSB) were applied to poultry manure (PM) and composted for 50 days; those without the WSB treatment were used as a control. The results revealed the dominant phyla to be Chytridiomycota , Mucoromycota , Ascomycota and Basidiomycota , while Batrachochytrium , Rhizophagus, Mucor, and Puccinia were the superior genera. In particular, the diversity of Chytridiomycota and Ascomycota was more abundant among all of the treatments. Overall, the diversity of the fungal species was correspondent, but relative abundance varied significantly among all of the composts. Principle Coordinate Analysis (PCoA) and Non-Metric Multi- Dimensional Scaling (NMDS) indicated that different concentrations of WSB applied treatments have significantly distinct fungal communities. In addition, correlation analyses of fungal interactions with environmental elements via HEMI also indicate a clear difference among the treatments. Ultimately, the relative abundance of fungal composition significantly influenced the PM compost treated by the WSB. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the impact of different combinations of wheat straw biochar, compost and biogas slurry on maize growth, physiology, and nutritional status in less productive soils. The experiment was performed as a completely randomized block design in a greenhouse pot experiment. The compost and biogas slurry were applied with and without biochar. The results revealed that a combination of biochar, compost, and biogas slurry enhanced the cation exchange capacity (31%), carbon (83%), phosphorus (67%) and potassium (81%) contents in the soil. Likewise, a significant increase in soil microbial biomass carbon (15%) and nitrogen (37%) was noticed with the combined use of all organic amendments. Moreover, the combined application of biochar, compost and biogas slurry enhanced soil urease and β-glucosidase activity up to 96% and 67% over control respectively. In addition, plant height, chlorophyll content, water use efficiency and 1000-grain weight were also enhanced up to 54%, 90%, 53% and 21% respectively, with the combined use of all amendments. Here, biochar addition helped to reduce the nutrient losses of compost and biogas slurry as well. It is concluded that biochar application in combination with compost and biogas slurry could be a more sustainable, environment-friendly and cost-effective approach, particularly for less fertile soils.

[Display omitted] • Food waste, saw dust and wheat straw biochar were utilized in composting. • Biochar enhanced fungal dynamics and higher abundance was observed in T6 with 15% biochar. • Basidiomycota and Ascomycota dominated with 5.36% and 94.64% in compost. • Kluyveromyces (3.76%) and Candida (5.34%) were most common genera. This study aims to examine the effects of biochar on fungal dynamics during food waste composting. The different dosage of wheat straw biochar from 0 to 15% (0%, 2.5%, 5%, 7.5%, 10%, and 15%) were used as an additive to composting and examined for 42 days. The results showed that Ascomycota (94.64%) and Basidiomycota (5.36%) were the most dominant phyla. The most common fungal genera were Kluyveromyces (3.76%), Candida (5.34%), Trichoderma (2.30%), Fusarium (0.46%), Mycothermus - thermophilus (5.67%), Trametes (0.46%), and Trichosporon (3.38%). The average number of operational taxonomic units were 469, with the greatest abundance seen in the 7.5% and 10% treatments. Redundancy analysis revealed that different concentrations of biochar applied treatments have significantly distinct fungal communities. Additionally, correlation analyses of fungal interactions with environmental elements, performed through a heatmap, also indicate a distinct difference among the treatments. The study clearly demonstrates that 15% of biochar has a positive impact on fungal diversity and improves the food waste composting. [ABSTRACT FROM AUTHOR]

The biochars were produced from wheat straw (WSBC) at different pyrolytic temperatures. Biochars were characterized by multiple instrumental techniques and were applied to remove Cd from aqueous solution. The removal mechanism was explored, and the quantitative information regarding the relative contribution of related mechanisms to Cd sorption on biochars was provided. The results showed that pseudo-second-order kinetic model, TC (two-compartment) model, and Freundlich isotherm could well fit the process of Cd sorption on biochars. The sorption could be divided into fast and slow adsorption stages. The order of the Cd removal capacity by biochar was WSBC700 > WSBC500 > WSBC300. Adsorption amount of Cd by biochar reduced when the biochar was rinsed with 1.0 M HCl, which indicated that acid-soluble minerals in biochar played an important role during the Cd removal process, especially for the biochar obtained at high pyrolytic temperature. Various equipments were used to investigate the interaction mechanism between biochar and Cd. Mineral precipitation, surface complexation, and cation-π interaction were the main mechanisms of Cd sorption on the biochars. The contribution of cation-π mechanism was in the range of 25.42-48.58%, 2.18-19.30% for surface complexation and 32.12-72.41% for mineral precipitation, respectively. The pyrolytic temperature significantly influenced the removal capacity and mechanism of Cd on biochars. The cation-π mechanism was predominant for biochar obtained at lower pyrolytic temperature. However, mineral precipitation mechanism played a crucial role for biochar obtained at high pyrolytic temperature. These results are helpful for the design or screening of “engineered biochar” to act as sorbents to remove or immobilized Cd in polluted soil or water.ᅟ [ABSTRACT FROM AUTHOR]

European lacustrine systems are frequently exposed to nitrate (NO3-) pollution causing eutrophication processes. An example of these lakes is Shkodra Lake, a large, shallow lake shared by Albania and Montenegro, in the Balkans Peninsula. Shkodra Lake is a natural sink that collects NO3- from agricultural activities, widely diffused in the surrounding area. The additions of wheat straw and biochar have been suggested to increase soil NO3- retention of agricultural lands. To better understand the role of these two organic soil amendments in mitigating NO3- leaching from arable lands, a pot experiment using a representative sandy loam soil of the Skodra Lake basin was performed. More specifically, a greenhouse experiment with Lolium multiflorum L. and Zea mays L., was carried out for three months, to evaluate the concentrations of NO3--N in leachate and the cumulative leaching losses of NO3- -N, after wheat straw (10 Mg ha-1) and biochar (10 Mg ha-1) soil addition, under the same rate of NPK fertiliser (300 kg ha-1). The effect of the two organic amendments on nitrate retention, was evaluated according to two methods: i) Soil NO3--N leaching with distilled water; and ii) Soil NO³--N extraction with 2M KCl. The leached NO3--N and the «Potentially Leachable» NO3--N (2M KCl extraction) were respectively determined. N uptake by plants, as well as the Nitrogen Use Efficiency were also calculated. A retention effect on nitrate was found in Lolium multiflorum L. and wheat straw treatments compared to control, by reducing leached NO3--N almost to 35%. In SBFL (soil+biochar+fertiliser+Lolium) treatment, biochar effectively reduced the total amount of nitrate in leachate of 27% and 26% compared to SFL (soil+fertiliser+Lolium) and SSFL (soil+straw+fertiliser+Lolium) treatments, respectively. The potentially leachable NO3--N was two to four times higher than the leached NO3--N. The amount of potentially leachable NO3--N per hectare ranged from 220 in SL (soil+Lolium) treatment, to 500 kg ha-1 in SFL. N plant uptake values ranged from 18.16 mg kg-1 in the non-fertilised treatment to 58.06 mg kg-1 soil in SSFM (soil+straw+fertiliser+maize) treatment. The NUE showed a similar trend (from 0 in the non-fertilised treatment to 47.9% in SSFM). Results indicated a mitigating action of biochar on leaching of NO3--N (leached up to 100 kg ha-1), despite the retention effect of the two different amendments applied. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of wheat straw biochar (WSB) on food waste composting was studied. • Firmicutes, Proteobacteria and Bacteroidota were the dominate phyla of the treatments. • Lactobacillus fermentum and Bacillus thermoamylovorans were higher abundance. • Bacillus , Weissella , and Paracoccus were considered as possible biomarkers. The impact of wheat straw biochar (WSB) on bacterial dynamics succession during food waste (FW) composting was analyzed. Six treatments [0(T1), 2.5(T2), 5 (T3), 7.5 (T4), 10 (T5), and 15 %(T6)] dry weight WSB were used with FW and saw dust for composting. At the highest thermal peak at 59 ℃ in T6, the pH varied from 4.5 to 7.3, and electrical conductivity among the treatments varied from 1.2 to 2.0 mScm1. Firmicutes (25–97 %), Proteobacteria (8–45 %), and Bacteroidota (5–50 %) were among the dominate phyla of the treatments. Whereas, Bacillus (5–85 %), Limoslactobacillus (2–40 %), and Sphingobacterium (2–32 %) were highest among the identified genus in treatments but surprisingly Bacteroides was in greater abundance in the control treatments. Moreover, heatmap constructed with 35 various genera in all the treatments showed that Gammaproteobacterial genera contributed in large proportion after 42 days in T6. Additionally, a dynamic shift from Lactobacillus fermentum to higher abundance of Bacillus thermoamylovorans was reported on 42 days of FW composting. Biochar 15 % amendment can improve FW composting by influencing bacterial dynamics. [ABSTRACT FROM AUTHOR]

Soil amendments of wheat straw biochar (BC), lignocellulosic substrate (LS), BC+LS, and BC+LS+BR (surfactant Brij30) were investigated for the first time in order to remedy polycyclic aromatic hydrocarbons (PAHs)-polluted soil using pilot scale microcosm incubation. We hypothesized that the removal of PAHs could be inhibited due to the adsorption and immobilization of biochar and the inhibition depends on the molecular-weight of PAHs. The removal rates of phenanthrene (PHE) and Benzo[a]pyrene (BaP) ranked as C=BC>LS=LS+BC=LS+BC+BR and C=BC=LS+BC+BR>LS=LS+BC. Wheat straw biochar inhibited the removal of PHE and accelerated BaP removal. The activity of Dehydrogenase (DH) was depressed by the addition of the biochar while the activity of polyphenol oxidase (PPO) was stimulated. Lignocellulose and surfactant are favourable to sustain soil microbiological activity and the removal of PAHs although the diversity of bacterial community was not significantly changed. The findings implied that the components of PAHs are necessary to consider when the amendments are implemented by associated biochar in PAH-polluted soil. [ABSTRACT FROM AUTHOR]

Surface modification can improve biochar adsorption capacity. Biochars were produced from wheat straw through low-temperature pyrolysis at approximately 450°C, activated with hydrochloric acid (HCl), and coated with iron (FeCl36H2O) of different amounts. Results showed that activation with HCl and coating with iron can significantly increase biochar adsorption capacity. The increase after HCl treatment was very small at a high ratio of iron to biochar. The optimal ratio of iron to biochar for iron-coated biochar was 0.70. Adsorption capacity was calculated based on the amount of pure nitrogen or phosphorus. The maximum adsorption capacities were 2.47 and 16.58 mg g−1. The most effective pH values for nitrate and phosphate removal were 3 and 6, respectively. The active substance of the optimal-modified biochar (OMB) was amorphous FeOOH, and the structurewas the hydroxylated mineral surface of OMB in a water solution. The equilibrium pH of the adsorption solution was lower than 7 even when the initial pH of the solution was 11 becausechanged into,, and H3O+with the increase in pH. Adsorption experiments showed that OMB can be utilized to remove nitrate and phosphate from water. [ABSTRACT FROM PUBLISHER]

[Display omitted] • Adsorption behavior of Pb (II) on biochar was 3D in situ visualized using micro-CT. • Normalized adsorption isotherms and kinetics of Pb (II) on biochar were shown. • Micro-CT results were in line with the adsorption tests and model simulation. • Pb (II) was preferentially adsorbed onto the surface of biochar. • Pb (II) experienced surface adsorption and intraparticle diffusion at 100 mg/L. The micro-CT technique was applied in adsorption visualization of Pb (II) on the pellet biochar derived from wheat straw to provide information on understanding the complex heavy metal-biochar interaction during the process. The 3D distribution of Pb (II) on the biochar was well in line with the results of isothermal and kinetic adsorption experiments as well as those of simulation with Langmuir and Weber-Morris intraparticle diffusion (IPD) models. It was shown that Pb (II) was preferentially adsorbed on the surface of the biochar at an initial Pb (II) concentration of 50 mg/L. However, at a higher initial concentration of 100 mg/L, the adsorption process occurred in a two-stage regime, namely rapid surface adsorption followed by slow intraparticle diffusion. This research offered a new way for investigation of the complex adsorption behavior of heavy metals on biochar, as well as construction and optimization of related adsorption models. [ABSTRACT FROM AUTHOR]

Modification of pristine biochars has received increasing attentions due to the significant potential in enhancing adsorption performance. In this work, the co-modification of KOH and KMnO 4 on biochar (K-Mn-BC) was performed, with the effect of KOH/KMnO 4 modification on biochar properties and their adsorption toward tetracycline (TC) being extensively explored. Results showed that KOH/KMnO 4 modification can significantly regulate biochars to form hierarchical structure. The obtained K-Mn-BC was characterized with a high specific surface area (1524.6 m2 g−1) and total pore volume (0.85 cm3 g−1). In addition, the K-Mn-BC exhibited a high adsorption capacity of 584.19 mg g−1 toward TC at 318 K, and pseudo-second-order (R 2:0.993～0.998) and Langmuir (R 2: 0.834～0.874) models can fit well with the adsorption behavior. Moreover, the obtained K-Mn-BC can efficiently adsorb TC within a wide pH range (3.0–10.0), and were not affected by the co-existing ions. The possible mechanisms for the high adsorption capacity were ascribed to the pore filling and π-π interaction, following by hydrogen bonding and metal complexation. The obtained K-Mn-BC is a suitable adsorbent for TC removal from water due to the hierarchical structure, high adsorption capacity, and stable adsorption effect. [Display omitted] • Co-modification of KOH and KMnO 4 on biochar for enhanced TC adsorption was studied. • K-Mn-BC exhibited a hierarchical structure. • Pseudo-second-order and Langmuir models can well fit the adsorption behavior. • The maximum adsorption capacity of K-Mn-BC toward was 584.19 mg g−1. • The prevailing mechanisms of TC on K-Mn-BC were revealed. [ABSTRACT FROM AUTHOR]

Agro-Wastes are identified as to manufacture potential valuable organic biochar fertilizer product economically while also managing the waste. Biochar (BC) produced from agriculture waste is helps to improve the soil because of its neutral pH, addition of organic carbon to the soil and lower salt index values. This study focused on the development of nano-biochar into a more enhanced biochar product where it was checked whether the biochar derived from wheat straw can absorb nutrients and then act as support matter for releasing micro-nutrients and macro-nutrients for the plants on slow liberation basis. Wheat biochar (WBC) and wheat nano-biochar (WBNC) were synthesized by pyrolysis at two different temperatures and nutrients were fused into the WBC via impregnation technique. Physical parameters such as Proximate, Ultimate analysis & other were also studied and inspected by standard control procedures. Studies were also carried out on water retention (WR), water absorbance (WA), swelling ratio (SR) and equilibrium water content (EWC) for all samples; data was collected and compared for the better sample. Slow-release studies performed portrayed the release pattern of nutrients for prolonged periods, which are very important for the plant growth, yield and productivity. Overall, the experimental results displayed that BNC produced at 350 °C showed promising features of (SI:0.05, SR: 3.67, WA:64%, EWC:78.6%, FC:53.05% and pH:7.22), is a good substance however the nano-biochar has improved results; environmental friendly & could be utilized as a potential fertilizer on slow release for sustainable and green agriculture application. [Display omitted] • Slow pyrolysis was performed on 300–350 °C to product wheat biochar. • Biochar impregnated with Micro-Macro nutrients to synthesize Nano-biochar. • Nano-biochar at 350 °C displayed better slow-release characteristics. • Sustainable agriculture product with lower salt index and pH value of 7.22. [ABSTRACT FROM AUTHOR]

The co-application of biochar and fertiliser has emerged as a strategy for improving soil quality and crop growth; however, the impact of the type of fertiliser added with biochar to the soil on leaching and retention of nutrients is not well studied. In this study, a leaching experiment was undertaken using a series of column lysimeters incorporating a wheat straw biochar (WSB) and two fertiliser types—chemical fertiliser (CF), or rock mineral fertiliser (MF). The results showed that CF and MF leached a similar amount of NH4+ with or without WSB, but the NO3– leaching occurred from CF-treated soil which was decreased by CF + WSB application. In contrast, NO3– leaching was not affected by WSB in MF-treated soil. Both CF and MF with or without WSB increased the cumulative leaching of P and K. Nevertheless, WSB application increased soil P and K contents after leaching, which was attributed to intrinsic nutrient release from biochar. Shoot growth and P and K uptake also increased with biochar amendment, whereas root growth and N uptake did not change. Therefore, the results highlight that biochar addition can improve nutrient retention and plant growth by reducing nutrient leaching, mainly dependent on biochar and fertiliser type combination used. It suggests that the adsorption properties of biochar for nutrient retention and subsequent release need to know before their broad application to soils as amendments. [ABSTRACT FROM AUTHOR]

Previous studies have focused mostly on the effects of the single application of biochar on soil organic carbon mineralization. However, these studies were not able to infer the effect of extended biochar supplementation at distinct concentrations on the systematic relationship between soil properties and organic carbon mineralization. Thus, we investigated the soil characteristics, such as organic carbon mineralization, hydraulics, aggregation, and microbiota under the biochar supplementation for an experimental period of six years in a rapeseed-sweet potato rotation field experiment in upland red soil in southeast China. The structural equation modeling (SEM) was constructed to reflect the systematic relationship between soil properties and organic carbon mineralization. The results of our study revealed that the biochar significantly reduces the soil bulk density and enhances the soil water holding capacity, but these effects diminished with the time. We also found that low-medium biochar application rates (0.5% and 1%) considerably increased the soil microbiota, aggregation, and potentially mineralizable carbon (C 0). Moreover, high application rates (2%) of biochar inhibited the carbon mineralization and increased the soil organic carbon fixation. Besides, the outcome of SEM demonstrated that the hydraulics, aggregation, and microbiome of soil impacted the C 0. The effects of soil aggregation and microbiota on C 0 were higher during 2014–2016 than they were in 2011–2013, and the negative impact of soil hydraulics on C 0 diminished with time. In conclusion, the effects of biochar on physicochemical characteristics and organic carbon mineralization of soil differ with the dosage and duration of biochar supplementation. Also, a high dose of biochar addition can substantially reduce CO 2 emission from soil to the atmosphere. Image 1 • Biochar significantly enhance hydraulics properties, while the effects weakened over time. • Low-medium dose of biochar can improve the soil aggregates stability and soil microorganisms. • High dose biochar can inhibit the carbon mineralization and increase the fixation of soil organic carbon. • SEM can well reflect the systematic relationship between soil organic carbon mineralization and soil properties. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the impact of different combinations of wheat straw biochar, compost and biogas slurry on maize growth, physiology, and nutritional status in less productive soils. The experiment was performed as a completely randomized block design in a greenhouse pot experiment. The compost and biogas slurry were applied with and without biochar. The results revealed that a combination of biochar, compost, and biogas slurry enhanced the cation exchange capacity (31%), carbon (83%), phosphorus (67%) and potassium (81%) contents in the soil. Likewise, a significant increase in soil microbial biomass carbon (15%) and nitrogen (37%) was noticed with the combined use of all organic amendments. Moreover, the combined application of biochar, compost and biogas slurry enhanced soil urease and β-glucosidase activity up to 96% and 67% over control respectively. In addition, plant height, chlorophyll content, water use efficiency and 1000-grain weight were also enhanced up to 54%, 90%, 53% and 21% respectively, with the combined use of all amendments. Here, biochar addition helped to reduce the nutrient losses of compost and biogas slurry as well. It is concluded that biochar application in combination with compost and biogas slurry could be a more sustainable, environment-friendly and cost-effective approach, particularly for less fertile soils. [ABSTRACT FROM AUTHOR]

This study extends the application of pyrolyzed biochar and investigates its influence on the mechanical, sorption and microstructure properties of magnesium phosphate cement mortar. Biochar was produced by the pyrolysis of wheat straw biomass by controlled burning and its replacement level was kept up to 1.5%. At the age of 30 days, the compressive and flexural strength of mortar containing 1.5% biochar was 17.3% and 9.0% higher as compared to the control mortar, which was associated with the micro-filler and internal reservoir effect of biochar particles. Inclusion of biochar considerably improved the resistance of magnesium phosphate cement in the water environment. Sorptivity and water absorption of mortar containing 1.5% biochar was reduced by 33.8% and 25% respectively than the control mortar. Biochar densified the microstructure of mortars by filling the microcracks and blocking the pores. X-ray diffraction and Fourier transform infrared spectroscopy did not provide any information about the formation of new hydration products. Elemental analysis of mortar samples using energy dispersive spectroscopy showed the presence of some elements, which indicates the possibility of new hydration products. Based on the positive results in this study, future study will include the detailed chemical effect of biochar on magnesium phosphate cement. Unlabelled Image • Influence of biochar on the properties of magnesium phosphate cement was explored. • Improvement in mechanical properties was observed with the addition of biochar. • Use of biochar increased the water resistance of mortars. • Sorptivity and porosity was gradually reduced with the increase in biochar content. [ABSTRACT FROM AUTHOR]

Biochar is a cost-effective and multifunctional carbon material, which can be used to immobilize heavy metal (HM) in soil. To date, the immobilization of different HM by various biochars are well-studied, however, little is known about the release condition of the immobilized HM. As the released HM may bring a threat to the soil environment, it is critical to understand the release pattern of biochar-sorbed HM in soil. Herein, six wheat straw-derived biochars (WBs) pyrolyzed under different temperature and duration time were loaded with zinc(Zn (II)), and the evolution of Zn(II) fractions in soils remediated by WBs over time was investigated by Community Bureau of Reference (BCR) three-step sequential extraction method. The main Zn(II) species sorbed on WBs were the Zn(II) sorbed on the acidic functional groups of WB and that sorbed on WB surface via electrostatic interaction. Generally, Zn(II) sorbed on high-temperature WB was more mobile than that sorbed on low-temperature WB. In the red soil, the soluble and exchangeable Zn(II) (i.e., Zn(II) in Fraction 1) in WB was inclined to transform to organic matter associated-Zn(II) (i.e., Zn(II) in Fraction 3) and residual Zn(II) (i.e., Zn(II) in Fraction 4). In the yellow-brown soil, the soluble and exchangeable Zn(II) in WB was prone to convert into amorphous Fe/Mn oxide associated-Zn(II) (i.e., Zn(II) in Fraction 2) and residual Zn(II). These results imply that Zn(II) sorbed by WB has the risk to be released into the soil environment, and WB produced at low temperature are more suitable to remediate soils with low/neutral pH. Unlabelled Image • Zn(II) sorbed on WB produced at high temperature was unstable • The WB-sorbed Zn(II) had the risk to be released into the soil environment • In the red soil, the soluble and exchangeable Zn(II) was prone to transform to OM associated and residual Zn(II) • In the yellow-brown soil, the soluble and exchangeable Zn(II) transformed to Fe/Mn oxides associated and residual Zn(II) [ABSTRACT FROM AUTHOR]

The use of nitrification inhibitors (NIs) such as 3,4–dimethylpyrazole phosphate (DMPP) has been suggested to diminish agricultural soil nitrate (NO 3 −) loss and increase nitrogen (N) use efficiency (NUE). However, the yield of ammonium (NH 4 +)–sensitive plants such as spinach (Spinacia oleracea L.) may be adversely affected by the application of NIs at high N levels and, on the other hand, the efficiency of the NIs may also be affected by soil amendments such as biochar. These two issues are still not adequately addressed. The aim of this study was to evaluate the effect of different N levels including DMPP or not in a calcareous soil with and without amendment of wheat straw biochar on spinach yield, NUE, nitrate concentration of spinach leaf, activity of enzymes nitrate reductase (NR) and nitrite reductase (NiR), and soil ammonium (NH 4 +) and NO 3 − concentration under greenhouse conditions. This experiment was carried out with different N rates factor at seven levels (un–fertilized, N0 ; fertilized with 50 mg N kg−1 soil, N50 ; fertilized with 75 mg N kg−1 soil, N75 ; fertilized with 100 mg N kg−1 soil, N100 ; fertilized with N50 + DMPP ; fertilized with N75 + DMPP ; and fertilized with N100 + DMPP) and biochar (BC) factor at two levels (0, 0%BC ; and 2% (w/w), 2%BC) with six replications over a 56–day cultivation period of spinach. Results showed that the application of DMPP had no significant effect on the yield of spinach plant at low and medium levels of N (50 and 75 mg N kg−1 soil), but decreased the yield of this plant at the higher level of N (100 mg N kg−1 soil). However, application of BC decreased the negative effect of DMPP on spinach yield as the yield in spinach plants fertilized with N75 + DMPP and N100 + DMPP significantly increased. Both application of DMPP and addition of BC to soil decreased leaf NO 3 − concentration by 29.2% and 16.3% compared to control, respectively. Biochar compared to control decreased NR activity by 46.3%. With increasing N rate, NR and NiR activities increased, but DMPP decreased the activities of both enzymes. Biochar reduced the efficiency of DMPP as soil NH 4 + concentration was higher in the treatments containing DMPP without BC at 56 days after planting. Biochar and DMPP could increase the quality of spinach plant through decreasing the leaf NO 3 − concentration. In general, wheat straw biochar counteracted DMPP–mediated negative effect on growth of spinach plant at high level of N by decreasing the efficiency of this inhibitor. These results provide the useful information for managing the application rate of N fertilizers including DMPP in biochar–amended soil. • DMPP at low levels of 50 and 75 mg N kg−1 soil had no effect on spinach yield but increased NUE. • DMPP at high level of 100 mg N kg−1 soil decreased both spinach yield and NUE. • Biochar (BC) reduced negative effect of DMPP on spinach yield. • BC significantly increased the yield of spinach plant fertilized with N75 + DMPP and N100 + DMPP. [ABSTRACT FROM AUTHOR]

• Highly efficient phosphorus removal over a wide pH range. • Adsorption properties of different materials evaluated by partition coefficient. • Excellent adsorption performance at low phosphate concentrations. Herein, we explored the modification of wheat straw biochar with chitosan, quaternary ammonium salt, and lanthanum for enhanced phosphate removal in environmentally relevant conditions. Specifically, a new amine protected cross-linking method was utilized to modify the absorbent material for maximum adsorption capacity, reaching 109 ± 4 mg P g−1. The high phosphate removal performance of the composite was not significantly affected in a broad range of temperature (15–45 °C) and pH (2.5–7). 30 min allowed reaching a 100% adsorption equilibrium for 100 mg P L−1, and 93% for 25 mg P L−1, thus, significantly reducing the treatment time compared to previous reports. The highest partition coefficient 172.1 mg g−1 μM−1 was obtained at a concentration of 25 mg L−1, and the phosphorus removal rate was as high as 99.98%, indicating La/GTB have great adsorption performance at low phosphate concentration. The adsorption mechanisms of the composite are extensively described, where electrostatic interaction, ligand exchange, and Lewis acid-base interaction contribute to the process. All of the above-mentioned advantages make the prepared composite of great interest for the development of materials for on-site phosphate removal. [ABSTRACT FROM AUTHOR]