Effects Of Biochar Research Articles

The effect of biochar in a specialty adsorbent on enhanced PFAS removal from surface water

An enhanced specialty adsorbent, referred to as biochar-based iron and perlite-integrated green environmental media (BIPGEM), was designed to simultaneously remove both long-chain PFAS mainly including perfluorooctanoic acid (PFOA) and Perfluorooctanesulfonic acid (PFOS) from surface water matrices. Batch-scale experiments using BIPGEM revealed that the removal efficiencies for PFOA and PFOS exceeded 98 % when treating a mixture of 3 short-chain PFAS, including perfluorobutanoic acid (PFBA), perfluorobutane sulfonic acid (PFBS), and hexafluoropropylene oxide dimer acid (GenX Chemicals). Additionally, a fixed-bed column study using BIPGEM revealed that the removal efficiencies of PFOA and PFOS were over 85 % within the first 12 h whereas the removal efficiency of PFBA was over 40 % at the fortieth hour. It was confirmed that the critical role of biochar in the removal of long-chain PFAS, particularly PFOA, can be attributed to the following factors: (1) the morphological structure and pore size of biochar restrict PFAS mobility, (2) the extensive specific surface area of biochar, with a positive charge (point of zero charge = 10.7) at the experimental condition, enhances the adsorption likelihood with the negatively charged hydrophilic heads of PFOA and PFOS, and (3) the presence of non-polar aromatic rings with high hydrophobicity in biochar facilitates the removal of PFAS through hydrophobic interactions with the functional groups of PFAS.

Effect of Rice Residue Biochar on Lead Remediation, Growth, and Micronutrient Uptake in Indian Mustard (Brassica juncea (L.) Czern.) Cultivated in Contaminated Soil.

A pot experiment at Punjab Agricultural University, Ludhiana, India, assessed rice residue biochar's effect on remediating lead and cadmium in soil and on Indian mustard growth. Soil spiked with Cd (0, 10, 25mg kg⁻¹) and Pb (0, 25, 50mg kg⁻¹) was amended with biochar (0, 0.5, 1, 2% w/w) in a completely randomized design with three replications. Adding 2% biochar reduced DTPA-Pb in soil and Pb in shoots by 61% and 56%, respectively. Biochar increased dry matter yield (DMY) by 18% at 1% but decreased by 19% at 2%. The 1% biochar increased shoot Fe, Mn, Zn, and Cu by 11.39%, 26.74%, 5.89%, and 17.72%, respectively. Rice residue biochar significantly improved the DMY and micronutrient content of Indian mustard by reducing lead contamination in co-contaminated soil.

A Comparative Effect of Sustainable Materials on the Immobilization, Geochemical Fractions, Bioaccumulation, and Translocation of Ni in Smelter- and Mine-Polluted Soils

The present study holds significant implications, as it aims to investigate the comparative effect of biochar, zeolite, and bentonite minerals on the stabilization of Ni fractions, bioaccumulation, translocation indices, and the reduction in their absorption by pakchoi in smelter- and mine-contaminated soils. The results, which are of great interest, showed that the maximum fresh and dry biomasses of pakchoi were observed up to 28.21 and 18.43% for smelter-polluted soil and 61.96 and 67.90% for mine-contaminated soil amended with zeolite compared to the control. Applying zeolite increased pakchoi chlorophyll SPAD values 1.17-fold in smelter soil and 1.26-fold in mine-polluted soil. The highest Ni immobilization in smelter and mine soil was observed at 76.8 and 85.38% with the application of bentonite, which increased soil pH and CEC. The application of biochar, bentonite, and zeolite reduced the Ni residual, oxidizable, and acid-soluble fractions, but biochar and bentonite increased the reducible fraction of Ni in smelter soil. The highest reduction in Ni in the shoot and root was noted as 82.08 and 68.28% of smelter-polluted soil and 77.25 and 89.61% of mine-polluted soil with bentonite compared to control soil. Overall, it has been concluded that biochar, zeolite, and bentonite can be successfully used to mitigate the Ni concentration in smelter- and mine-polluted soil and reduce uptake by vegetable crops.

Biochar affects soil properties over 1 m depth in an alkaline soil of north China Plain

Biochar has been shown to enhance soil quality and agricultural yields. Previous studies about biochar's effect on soil properties mainly concentrated on the top 30 cm layer but less on the subsoils. Given the subsoil's active role in climate change mitigation and its significance for nutrient cycling and crop productivity, understanding biochar's effects at depth is crucial. This study explored the responses of soil organic carbon (SOC), total nitrogen, available potassium, available phosphorus, pH, and electrical conductivity to different doses of biochar addition (0, 10, 20, and 30 Mg/ha) over the 1 m depth of alkaline soil. Additionally, the impact of biochar on soil microbial community was assessed in the top 20 cm. Results demonstrated that biochar addition can increase SOC and improve soil properties in deep soil horizons. Specifically, a 30 Mg/ha biochar addition increased SOC by 1.2–10.1 Mg C/ha in the 10–40 cm layer and by 3 Mg C/ha in the 60–80 cm depth over two years. Additionally, biochar addition at this rate increased total nitrogen by 0.2–0.3 g N/kg in the 10–40 cm depth and elevated available potassium across the 1 m profile, with a maximum increment of 313 mg/kg in the surface 10 cm and a minimum of 97 mg/kg in the 40–60 cm depth. While biochar application did not increase available phosphorus, it resulted in a minor decrease in soil pH (<0.7 units) and a slight increase in electrical conductivity. Moreover, biochar addition did not significantly alter the soil microbial community. Our findings underscore the importance of considering subsoils when evaluating biochar's impact on soil properties. We suggest that subsoils should be considered when estimating the potential of cropland management for increasing soil carbon sequestration and improving soil conditions.

Short-term effects of co-applied biochar and paper mill biosolids on soil microbial communities under field conditions

Biochar and paper mill biosolids (PB) are reported to improve soil fertility, crop growth and indirectly conditions for soil microbial communities. However, it is unclear how the co-application of these materials impacts soil microbial communities under field conditions. A study was initiated in 2018 in Québec, QC, Canada and fine roots and rhizosphere soil were sampled to determine the effects of co-application of wood biochar (0, 10, and 20 Mg dry wt. ha−1) and PB (0 and 30 Mg wet wt. ha−1) on the percentage of corn (Zea mays L.) and soybean (Glycine max L. Merr.) root colonization by arbuscular mycorrhizal fungi (AMF), soil microbial biomass phosphorus (MBP) and microbial (Bacteria, Fungi and AMF) diversity and community structure in a temperate loamy soil. Co-applying PB and biochar increased soil MBP compared with the control and biochar-only application. Applying PB alone or with biochar increased the level of root colonization by AMF compared with the control and biochar-only application in soybean but not in corn. Overall, biochar and PB application had no significant effect on bacterial and AMF diversity and community structure compared with the control. However, applying PB alone or with biochar decreased the fungal alpha diversity (Shannon and Simpson indices), affected several fungal taxa abundances and shifted the fungal community structure as indicated by the principal coordination analysis (PCoA). Our results provided an understanding on the short-term effects of co-applied wood biochar and PB on microbial communities of a temperate loamy soil under field conditions, as well as scientific bases for further investigation.

Effects of Biochar on Arsenic-Contaminated Soil: Chemical Fractionation, Vegetation Growth, and Oral Bioaccessibility.

Contamination by arsenic (As) is a pressing environmental and public health issue requiring urgent remediation strategies. One cost-effective and eco-friendly method involves adding stabilizing agents to soils to reduce As mobility. However, remediation projects must also address potential ecotoxicological effects. These effects may include harmful impacts on both aquatic and terrestrial organisms, including plants, disruption of ecosystem balance, and the potential bioaccumulation of toxic substances in the food chain. Biochar from organic fraction of municipal solid waste (OFMSW) shows promise for As-contaminated soil remediation. Pot experiments were conducted with soil contaminated with As (100 mg kg-1) and amended with biochar produced at three different temperatures (300, 500, and 700 °C) and addition rates (1 and 5%, w/w). Chemical fractionation showed higher As concentration in a less accessible fraction (F4). Biochar amendments did not significantly differ from the control in As immobilization, but enhanced maize (Zea mays) growth and reduced As uptake, with the most promising results seen with 1% of biochar produced at 700 °C. The bioaccumulation factor (BCF) and translocation factor (TF) were both lower than 1, indicating a low absorption of As and minimal translocation from the root to the shoot. The bioaccessible percentage was higher in the samples treated with biochar compared to the control. According to the results, biochar showed no satisfactory potential for As immobilization and its approach of pretreatment/modification should be tested regarding possible improvements in the immobilization performance of As. Since most contaminations involve multiple contaminants simultaneously, it is essential to test the interactions between arsenic and other pollutants to understand the effects of biochar in such complex scenarios, which will be explored in future studies. Graphical abstract.

Effects of oil palm trunk biochar as filler on physical and mechanical properties of deproteinised and epoxidised natural rubber latex foam

Effects of oil palm trunk biochar as filler on physical and mechanical properties of deproteinised and epoxidised natural rubber latex foam

Paddy straw biochar amended sediment enhances pond productivity, growth and physiological profile of Penaeus vannamei cultured in inland saline nursery ponds.

The growing interest in commercial Inland saline aquaculture has taken momentum across the globe due to the available technologies for aquaculture and the abundant resources of saline groundwater. However, the critical problems in inland saline ponds are degraded soil and imbalanced or deficient nutrients. To address these issues, a 75-day experiment was conducted to explore the effects of Paddy Straw Biochar (PSB) as a sediment amendment on sediment quality, water characteristics, growth parameters, and the well-being of Penaeus vannamei reared in inland saline environments. PSB was applied to the nursery ponds at 1 ton/hectare (Treatment, T1) and 2 ton/hectare (Treatment, T2). The findings of water quality parameters showed a significant increase in K+ and Mg++ with a decrease in ammonia-N levels in biochar-applied ponds. Similarly, the addition of biochar to ponds (T2) resulted in improved sediment characteristics with enhanced water holding capacity (24.75%), increased soil organic carbon content (77.94%), pH levels (0.37 units), cation exchange capacity (43.15%), available potassium (16.3%), and lower bulk density (12.61%) compared to ponds subjected to control conditions at the end of the experiment. Over the experiment, improvements in sediment and water quality parameters followed the T2 > T1 > control trend. Growth characteristics showed a significant rise in the percentage of weight gain (12.398 ± 0.12), SGR (11.80 ± 0.01% day-1) and PER (2.39 ± 0.01) with reduced FCR (1.19 ± 0.00) in biochar-treated ponds (T2), followed by T1 and control. The digestive enzyme activity (amylase) and metabolic enzymes like hepatopancreatic alanine aminotransferase (ALT) and muscle ALT activities were significantly higher in shrimps raised in the biochar-applied ponds. On the other hand, the oxidative stress enzyme superoxide dismutase (SOD) in gills, muscles, and hepatopancreas (HP) exhibited lower values, suggesting reduced oxidative stress due to the biochar amendment of the pond sediment. Overall, the study recommends incorporating PSB at a rate of 2 t/ha into nursery pond sediment to enhance water quality, physiological status, and the growth of P. vannamei juveniles. Moreover, this approach improves soil and water characteristics in saline soils, making it an effective culture practice in degraded environments.

Maize-Straw Biochar Enhances Soil Properties and Grain Yield of Foxtail Millet in a Newly Reclaimed Land

Large-scale land reclamation has become common in northwestern China; however, low soil fertility and poor soil water-holding capacity limit agricultural production on these reclaimed lands, requiring increased fertilizer and irrigation inputs. Biochar, produced from agricultural waste, has shown potential in improving soil quality and water-holding capacity. In this two-year field study (2021 and 2022), we investigated the effects of biochar produced from maize straw on soil properties and grain yield of foxtail millet grown on newly reclaimed land. Three biochar treatments (3000, 4500, and 6000 kg ha−1) were compared to a control (CK) with no biochar application. Biochar application resulted in increased soil organic matter, total phosphorus, total nitrogen, soil enzyme activity, and soil organic acid content. It also significantly decreased soil pH and bulk density. Compared with the CK, biochar increased available nitrogen from 29.7% to 108% in 2021 and 37.0% to 88.4% in 2022. Similarly, biochar increased available phosphorus from 64.7% to 143% in 2021 and 41.9% to 96.5% in 2022. Grain yields ranged from 3092 to 4753 kg ha−1. Biochar treatments increased grain yield compared to the CK, ranging from 12.2% to 24.6% in 2021 and 27.1% to 53.7% in 2022. Correlation analysis revealed that soil pH was negatively related to soil oxalic acid content, phosphorus content, and sucrase activity. Available nitrogen and phosphorus contents were negatively related to soil bulk density and positively related to catalase activity. Soil water content was negatively correlated with soil bulk density and positively correlated with organic matter. In conclusion, biochar improved the rhizosphere soil pH and the effectiveness of soil fertility in the newly reclaimed soil, resulting in an enhanced grain yield of foxtail millet.

Assessment of the Effects of Biochar on the Physicochemical Properties of Saline–Alkali Soil Based on Meta-Analysis

Enhancing global agricultural sustainability critically requires improving the physicochemical properties of saline–alkali soil. Biochar has gained increasing attention as a strategy due to its unique properties. However, its effect on the physicochemical properties of saline–alkali soil varies significantly. This study uses psychometric meta-analysis across 137 studies to synthesize the findings from 1447 relatively independent data sets. This study investigates the effects of biochar with different characteristics on the top 20 cm of various saline–alkali soils. In addition, aggregated boosted tree (ABT) analysis was used to identify the key factors of biochar influencing the physicochemical properties of saline soils. The results showed that biochar application has a positive effect on improving soil properties by reducing the sodium adsorption ratio (SAR) and the exchangeable sodium percentage (ESP) by 30.31% and 28.88%, respectively, with a notable 48.97% enhancement in cation exchange capacity (CEC). A significant inverse relationship was found between soil salinity (SC) and ESP, while other factors were synergistic. Biochar application to mildly saline soil (&lt;0.2%) and moderately saline soil (0.2–0.4%) demonstrated greater improvement in soil bulk density (SBD), total porosity (TP), and soil moisture content (SMC) compared to highly saline soil (&gt;0.4%). However, the reduction in SC in highly saline soil was 4.9 times greater than in moderately saline soils. The enhancement of soil physical properties positively correlated with higher biochar application rates, largely driven by soil movements associated with the migration of soil moisture. Biochar produced at 401–500 °C was generally the most effective in improving the physicochemical properties of various saline–alkali soils. In water surplus regions, for mildly saline soil with pH &lt; 8.5, mixed biochar (pH 6–8) at 41–80 t ha−1 was the most effective in soil improvement. Moreover, in water deficit areas with soil at pH ≥ 8.5, biochar with pH ≤ 6 applied at rates of &gt;80 t ha−1 showed the greatest benefits. Agricultural residue biochar showed superior efficiency in ameliorating highly alkaline (pH ≥ 8.5) soil. In contrast, the use of mixed types of biochar was the most effective in the amelioration of other soil types.

Effects of Biochar and Bradyrhizobium Inoculation on Nodulation, Growth, and Grain Yield of Soybean in the Guinea Savanna Agroecological Zone of Ghana

ABSTRACT Soybeans are a vital crop globally, significantly contributing to food security, soil fertility, and economic development. However, soil conditions can constrain their productivity, including nutrient deficiencies and acidity. This study explores the combined effects of biochar (BC) and Rhizobium inoculation (RI) on soybean growth, nodulation, and yield. The experiment was conducted over two growing seasons and employed a split-plot design with five BC application rates (0, 2, 4, 6, and 8 t ha− 1) and two RI levels (uninoculated and inoculated) across four replications. The results demonstrated that the integration of BC and RI significantly improved various growth parameters, including nodulation, biomass accumulation, pod number, and grain yield. The highest grain yield was observed at 8 t ha−1 BC with RI, yielding 3394 kg ha−1 in 2021 and 2542 kg ha−1 in 2022. This was identical to the yield attained with the 6 t ha−1 BC rate paired with RI in both years. The inoculated control treatment consistently demonstrated the lowest grain yield. Additionally, it showed a significant (p < .05) impact on the weight of one hundred seeds. The study also revealed significant and consistent relationships among soybeans’ growth and yield features. In conclusion, the findings suggest that the combined application of BC and RI has a positive impact on soybean yield and its key components.

The roles of nanoparticle-enriched biochars in improving soil enzyme activities and nutrient uptake by basil plants under arsenic toxicity

Enriched biochar with improved properties and functionality can play a significant role in providing sustainable solutions for mitigating heavy metal contamination in soil. In this experiment, the effects of solid and enriched biochars (potassium-enriched biochar (BC-K), magnesium-enriched biochar (BC-Mg), both individually and combined) were examined on soil microbial and enzyme activities, as well as nutrient uptake by basil plants cultivated in a soil with three levels of arsenic (nontoxic, 50 mg As kg−1 soil, and 100 mg As kg−1 soil). Biochar-related treatments, increased soil organic matter (65–76%), while decreased availability of arsenic (6–55%) in the soil. The microbial biomass carbon (by about 123%) and soil basal respiration (by about 256%), and soil enzymatic activities (β-glucosidase, urease, alkaline phosphatase, and dehydrogenase) were enhanced by enriched biochars under arsenic toxicity. The solid and particularly enriched biochars decreased arsenic content and improved nitrogen and phosphorus contents of roots and shoots, root length, root activity, and root and shoot biomass in basil plants. Therefore, it is conceivable to suggest that enriched biochars are superior treatments for improving nutrient absorption rates and basil growth under arsenic toxicity through decreasing arsenic mobility and increasing soil microbial activities.

Enhancing the Growth of Chili Plants and Soil Health: Synergistic Effects of Coconut Shell Biochar and Bacillus Sp. Strain Ya-1 on Rhizosphere Microecology and Plant Metabolism

To mitigate soil degradation and decrease dependency on chemical inputs in agriculture, this study examined the joint effects of coconut shell biochar and Bacillus strain Ya-1 on soil fertility, rhizosphere bacterial communities, and the growth of chili (Capsicum annuum L.). A controlled pot experiment with four treatments was conducted: control (CK), biochar only (C), Bacillus strain Ya-1 only (B), and a combination of both (BC). The BC treatment significantly enhanced the soil carbon and available phosphorus contents by approximately 20% and the soil nitrogen content and pH by 18% and 0.3 units, respectively, compared to the control. It also increased microbial biomass carbon and nitrogen by 25% and 30%, respectively, indicating improved soil microbial diversity as shown by the highest Pielou evenness index and Shannon index values. The combined application of biochar and the Ya-1 strain resulted in a 15% increase in chili plant height and a 40% improvement in root dehydrogenase activity, suggesting enhanced nutrient uptake and metabolism. Metabolic profiling showed shifts in stress response and nutrient assimilation under different treatments. Collectively, these results indicate the potential of biochar and microbial inoculants to significantly promote soil and plant health, providing a sustainable strategy to improve agricultural productivity and reduce reliance on chemical inputs.

Biochar decreased N loss from paddy ecosystem under alternate wetting and drying in the Lower Liaohe River Plain, China

Biochar addition to soil is widely utilized to enhance carbon sequestration and reduce fertilizer N losses. However, little research has been studied on the effect of biochar on reactive gaseous N losses, N leaching and grain yield in paddy ecosystems under water stress, especially in the Lower Liaohe River Plain with a higher water percolation. Our experiment was carried out in 2020 and 2021 utilizing a split-plot design with continuously flooding irrigation and alternate wetting and drying irrigation as main plots and without biochar addition and with 20 t·ha−1 rice husk-derived biochar addition as sub-plots. The results showed that alternate wetting and drying irrigation respectively, decreased N leaching and reactive N losses by 15.9 % and 11.3 % but also respectively, increased seasonal cumulative NH3 volatilization and N2O emissions by 5.0 % and 210 % on average. Rice husk-derived biochar addition significantly mitigated seasonal cumulative NH3 volatilization and N2O emissions by 8.8 % and 19.7 % in 2020, 20.7 % and 19.2 % in 2021, respectively, and decreased inorganic N leaching and reactive N losses by 8.3 % and 14.1 % in 2021. Biochar addition coupling with alternate wetting and drying respectively, mitigated cumulative NH3 volatilization and N2O emissions by 7.3 % and 19.3 % in 2020, and, 22.7 % and 22.0 % in 2021 as compared to that without biochar. Biochar did not differ from without biochar in inorganic N leaching under alternate wetting and drying irrigation in both years but significantly reduced reactive N losses by 17.8 % in 2021, which efficiently inhibited the alternate wetting and drying induced negative effects on the increase in reactive N losses. Therefore, biochar addition to paddy ecosystems under alternate wetting and drying could realize sustainable utilization of water resources, increase soil N fixation, and mitigate N losses.

A negative-carbon planning method for agricultural rural industrial park integrated energy system considering biomass energy and modern agricultural facilities

Biomass energy, recognized as a “zero-carbon” energy, has gradually become a crucial approach to promoting the low-carbon transformation of agricultural rural industrial parks (ARIP). Meanwhile, modern agricultural facilities (MAF) can play a significant role in adjusting agricultural load. Therefore, this paper proposes a negative-carbon planning method for the ARIP integrated energy system (IES). Firstly, carbon activities occurring during the operation of ARIP are sorted out and modeled based on the life cycle assessment (LCA) method, especially modeling the “zero-carbon” and “negative-carbon” benefits of biomass energy. At the same time, the models of both agricultural irrigation systems and straw bundling direct combustion heating are constructed in the ARIP planning. Then, a negative-carbon planning model for ARIP IES is established with the goal of minimizing the annualized total cost, where carbon emission reduction is integrated into the optimization objectives through carbon trading. On this basis, a two-stage distributionally robust optimization (DRO) planning model is constructed, where a box-like set and comprehensive norm constraints are used to model the seasonal differences of agricultural industry loads and the uncertainty of probability distribution in photovoltaic (PV) scenarios. Especially, a box set with adjustable uncertainty coefficients is introduced to simulate fluctuations of output in PV scenario. Finally, the CPLEX solver is used to solve the planning model. verify the effectiveness of the proposed planning method in enhancing the economic and environmental effects of ARIP. Results indicate that the proposed planning model can reduce the total cost by 49.584 × 104 $. Besides, the annual carbon emissions can be reduced from 37533.98 t CO2-eq to −15834.5 t CO2-eq. Especially, the carbon sequestration effect of biochar is the key link in achieving “negative carbon” in ARIP.

Exploring the synergistic benefits of biochar and gibberellic acid in alleviating cadmium toxicity

Cadmium (Cd) toxicity significantly threatens agricultural productivity and food safety. Developing effective strategies to enhance plant tolerance to Cd stress is essential. This study investigates the synergistic effects of biochar (BC) and gibberellic acid (GA3) on mitigating Cd toxicity in maize (Zea mays), focusing on their impact on oxidative stress markers and antioxidant enzyme activities. Soil samples were collected from the Cholistan Institute of Desert Studies (CIDS) and analyzed for trace metal ions and other properties. Biochar was produced from fruit and vegetable waste, washed, washed, deashed, and mixed with 10 ppm GA3. FH-1036 hybrid maize seeds were sterilized and planted in pots containing soil with varying Cd levels (0, 8, and 16 mg Cd/kg soil). Twelve treatments were established, including control, GA3, BC, and their combinations under different Cd stress levels. Plants were irrigated to maintain 60% field capacity and harvested at the V10 growth stage. Hydrogen peroxide (H2O2) contents and activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) were measured in roots, stems, and leaves. Statistical analysis was performed using OriginPro 2021, with ANOVA and Fisher’s LSD test used to determine significant differences. GA3 and BC treatments significantly reduced H2O2 levels in maize roots, stems and leaves under Cd stress. The combined treatment of GA3 + BC showed the most significant reduction in H2O2 levels across all plant parts, reducing root H2O2 by 50%, stem H2O2 by 55%, and leaf H2O2 by 53% under severe Cd stress (16 mg Cd/kg). SOD activity increased under non-stress conditions but decreased under Cd stress, with the highest activity observed in the combined treatment. POD activity followed a similar pattern, with GA3 + BC treatment resulting in the most significant increases under non-stress conditions and the least reductions under Cd stress. CAT activity showed substantial increases with GA3 + BC treatment, particularly under severe Cd stress, with a notable rise over the control. APX activity also exhibited enhancements with GA3 and BC treatments, especially in the combined treatment under various Cd stress levels. This study highlights the potential of combined BC and GA3 treatments in improving Cd stress tolerance in maize. Future research should focus on field trials and the long-term impacts of these treatments on crop productivity and soil health.

The Effects of Acid-Modified Biochar and Biomass Power Plant Ash on the Physiochemical Properties and Bacterial Community Structure of Sandy Alkaline Soils in the Ancient Region of the Yellow River

The application of biochar can effectively enhance soil organic matter (SOM) and improve soil structure. Biomass power plant ash (BPPA) is also rich in essential nutrients for plants, with similar carbon content. Considering production cost and agricultural waste recycling, it is beneficial to apply BPPA to improve soil fertility and quality. However, it remains unclear whether its ameliorative effects surpass those of biochar in alkaline soils. In the study, we set up seven pot experiments of faba beans in sandy alkaline soils from the ancient region of the Yellow River, including the controls (CK), different amounts of acid-modified BPPA (A1, A2, A3), and the same amounts of acid-modified biochar (B1, B2, B3), to compare their effects on soil physiochemical properties and bacterial community structure. The results indicate that the application of both biochar and BPPA can improve soil physiochemical properties. At the same dosage, the biochar application outperformed BPPA treatment in terms of soil physical properties such as bulk density (BD), maximum water-holding capacity (FC), and soil capillary porosity (SP2). Conversely, BPPA treatment displayed advantages in chemical properties such as readily oxidizable organic carbon (ROOC), total nitrogen (TN), alkaline nitrogen (AN), available phosphorus (AP), available potassium (AK), and electrical conductivity (EC). All the treatments enhanced the richness and diversity of bacterial communities, increasing the relative abundance of eutrophic groups such as Bacteroidota and Firmicutes while decreasing that of oligotrophic groups like Actinobacteriota. BPPA also increased the relative abundance of Proteobacteria, while the opposite was observed for biochar. Correlation analysis showed that the environmental factors such as soil pH, EC, TN, AK, SOM, and SP2 emerged as primary factors influencing the bacterial community structure of alkaline soils, significantly affecting their diversity and abundance. Among them, SP2 and SOM were the dominant physical and chemical factors, respectively. Overall, the application of both acid-modified BPPA and biochar can enhance the physiochemical properties of sandy alkaline soils, while the application of BPPA is superior for improving soil nutrient content and enhancing bacterial community structure. The study explores the potential mechanisms through which the application of acid-modified BPPA affects soil characteristics and microbial features, providing new insight into developing optimizing fertilization strategies for enhancing soil quality in the ancient region of the Yellow River.

The conversion of biomass to biochar decreases soil organic and inorganic carbon-derived CO2 emissions under different water conditions in karst regions

Due to the unique geological background and climatic condition, karst soils in southwest China are mainly developed on carbonate rocks and accompanied by frequent dry-wet alternations. Therefore, the effects of biomass (BS) and biochar (BC) on the soil carbon pools (especially inorganic carbon) in karst regions are different from those in non-karst regions. In order to understand the responses of soil organic carbon (SOC) and soil inorganic carbon (SIC)-derived CO2 emissions to BS and BC amendments under different water conditions in karst regions, a microscopic study under dry-wet alternate (DW) and constant moisture (CM) conditions was established to investigate the stability of BC, BS, and their effects on SOC and SIC pools by isotope double-labeling methods. Results showed that the contribution rates of SOC and SIC to soil CO2 emissions were 51.55 %–99.52 %, 0.48 %–48.45 % and 60.55 %–97.72 %, 2.28 %–39.45 % under DW and CM conditions, respectively. Compared with the control, BS application under different water conditions increased SOC and SIC-derived CO2 emissions by 929.78˗1443.39 % and 169.69˗335.71 %, respectively. However, BC amendment significantly decreased SOC and SIC-derived CO2 emissions, especially in the DW condition. The mean residence time (the inverse of the decomposition rate) of BC in karst soils under different conditions ranged from 657 to 3105 years, which was much higher than those of BS (7˗18 years). Therefore, the conversion of BS to BC in karst regions enhances carbon sequestration due to its stability of recalcitrant carbon, the decrease of SOC and SIC- derived CO2 emissions. This study is helpful to understand the quantification of CO2 sources from calcareous soils and elucidate the environmental behaviors and carbon sequestration potentials of BC or BS amendments in karst regions.

Impact of Poultry Manure-Derived Biochar and Bio-Fertilizer Application to Boost Production of Black Cumin Plants (Nigella sativa L.) Grown on Sandy Loam Soil

Biochar derived from poultry manure increases nutrient availability and promotes plant growth. This study investigated the effect of biochar with mycorrhizal and/or plant growth-promoting rhizobacteria on soil fertility, chemical properties, oil, and seed yield of Black Cumin (Nigella sativa L.) plants. A split-plot design with three replicates was employed, with biochar derived from poultry litter (BC) applied at rates of 0, 5, and 10 t ha−1, with beneficial microbes such as arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) affecting the growth of Black Cumin plants, and some soil properties, such as pH, electrical conductivity (EC), soil organic matter (SOM) and fertility index (FI), showing significant differences (p ≤ 0.05) among biochar and/or bio-fertilizer treatments. All biochar treatments with or without bio-fertilizers significantly increased pH, EC, OM and FI in comparison to the control treatment. The results demonstrated that applying biochar at the highest rate (10 t ha−1) increased fresh and dry capsule weights by 94.51% and 63.34%, respectively, compared to the control treatment (C). These values were significantly increased by 53.05 and 18.37%, compared to untreated plants when combined with AMF and PGPR. Furthermore, when biochar was applied in conjunction with both AMF and PGPR, fresh and dry capsule weights saw significant increases of 208.84% and 91.18%, respectively, compared to the untreated control treatment. The interaction between biochar, AMF, and PGPR significantly improved plant growth, yield, soil properties, and the fixed and volatile oil content of Black Cumin. These findings suggest that the combined application of biochar, AMF, and PGPR enhances nutrient availability and uptake, leading to improved growth and higher yields in Black Cumin plants, resulting in increased yield production.

A quantitative review of the effects of biochar application on the reduction of Cu concentration in plant: a meta-analysis.

Contamination and toxicity of copper (Cu) in soils are global issues, particularly in regions where Cu-based fungicides are utilized. Elevated Cu concentrations can lead to soil contamination and pose significant risks to the ecosystem, including plant life, wildlife, and human health. The application of biochar has been proposed as a viable strategy to mitigate Cu accumulation in plants. However, there is no quantitative and data-based consensus on the impact of biochar on plant Cu accumulation. In this meta-analysis, 624 data records from 65 published literature were collected and the effects of various factors, including biochar properties, experimental conditions, and soil properties on Cu accumulation in plants, were examined through meta-subgroup analysis and meta-regression models. The results obtained indicate a significant dose-dependent effect of biochar in decreasing Cu concentration in plants by an average of 23.45%. Soils with acidic pH values and medium textures were more conducive for biochar to mitigate Cu accumulation in plant tissues. In addition, manure biochar and green waste biochar were found to be more successful in decreasing Cu concentrations in plants compared to other biochar types. Biochar types with pyrolysis temperatures of > 600°C and pH values of ≥ 10 resulted in greater decreases in plant Cu concentration. Regarding biochar application, biochar minimum range of 1% in potting experiments and 20 t/ha in field experiments have been recommended to effectively decrease Cu concentration in plants. Overall, these findings provide valuable insights into Cu transfer mitigation through food chain to human bodies and for policymakers to take preventive measures.