Biochar-amended Soils Research Articles

Improved tomato development by biochar soil amendment and foliar application of potassium under different available soil water contents

The use of carbonaceous materials such as biochar has been considered an innovative solution in agriculture, especially to mitigate dry events caused by climate change. Biochar can improve water holding capacity, physical and chemical properties of soil, and increase the productivity of agricultural systems. However, underlying physiological mechanisms remain poorly understood. Mineral supplementation with potassium nitrate (KNO3) via foliar application is another promising strategy in agricultural management under irrigation deficit. Thus, we investigated the combined effects of biochar and foliar application of KNO3 on growth, yield, and physiology of tomato plants under different irrigation regimes. Results did not indicate a synergistic effect of biochar and foliar application of KNO3. Biochar application alleviated tomato plant stress under deficit irrigation, with plants showing better functioning of photosynthetic apparatus, higher yield, and better fruit quality, as well as increased water use efficiency. Coffee husk biochar (K-rich feedstock) fully met the tomato plant’s demand for K and partially met the demand for some other elements (P, Mg, Fe, Zn, Mn, and Cu). Although positive effects of KNO3 application was verified for some physiological and fruit quality components, overall, foliar application of KNO3 did not improve tomato yield. It is concluded that biochar soil amendment can be a promising practice to increase yield and quality of tomato fruits under deficit irrigation. Therefore, biochar-based fertilizer can be an alternative K source that also provides stable carbon to soil and helps to mitigate stress caused by prolonged drought.

Redox-mediated changes in the release dynamics of lead (Pb) and bacterial community composition in a biochar amended soil contaminated with metal halide perovskite solar panel waste

This study explored the redox-mediated changes in a lead (Pb) contaminated soil (900 mg/kg) due to the addition of solar cell powder (SC) and investigated the impact of biochar derived from soft wood pellet (SWP) and oil seed rape straw (OSR) (5% w/w) on Pb immobilization using an automated biogeochemical microcosm system. The redox potential (Eh) of the untreated (control; SC) and biochar treated soils (SC + SWP and SC + OSR) ranged from −151 mV to +493 mV. In SC, the dissolved Pb concentrations were higher under oxic (up to 2.29 mg L−1) conditions than reducing (0.13 mg L−1) conditions. The addition of SWP and OSR to soil immobilized Pb, decreased dissolved concentration, which could be possibly due to the increase of pH, co-precipitation of Pb with FeMn (hydro)oxides and pyromorphite, and complexation with biochar surface functional groups. The ability and efficiency of OSR for Pb immobilization were higher than SWP, owing to the higher pH and density of surface functional groups of OSR than SWP. Biochar enhanced the relative abundance of Proteobacteria irrespective of Eh changes, while the relative abundance of Bacteroidota increased under oxidizing conditions. Overall, we found that both OSR and SWP immobilized Pb in solar panel waste contaminated soil under both oxidizing and reducing redox conditions which may mitigate the potential risk of Pb contamination.

Rock Phosphate and Biochar Effects on Greenhouse Gas Emissions and Soil Fertility in Southern Alberta Potato Field

The application of biochar soil amendment and rock phosphate fertilizer to the soil could lead to achieving net zero emissions and food security; however, the effectiveness of using biochar and rock phosphate in southern Alberta brown chernozemic soil is not yet assessed. In the first trial of this study, varying levels of urea (N), with varying levels of biochar (B) were applied. The same level of rock phosphate (RP) and triple super phosphate (TSP) were applied to compare efficiency of the two fertilizers. The second trial involved applying the same nutrients, but with higher levels than the first trial. The results indicated that the fertilizer application rates did not affect the growth and yield of potatoes because of the application rates of the fertilizer and fertility status of the soil, whereas in the second trial, TSP and RP treatments had the same growth and yield. Furthermore, the high application rate of nitrogen fertilizer and RP with or without biochar in the potato plot emitted high nitrous oxide gas emissions while the low application rate of nitrogen fertilizer and RP kept the carbon dioxide in the soil. Nevertheless, in the second experiment, the application of biochar and rock phosphate reduced nitrous oxide and carbon dioxide emissions. We observed high residual nitrogen and manganese nutrients after harvest in the plot treated to rock phosphate and biochar. Therefore, rock phosphate and biochar have the potential to increase food production and mitigate climate change.

Investigating the growth promotion potential of biochar on pea (Pisum sativum) plants under saline conditions

Pea, member of the plant family Leguminosae, play a pivotal role in global food security as essential legumes. However, their production faces challenges stemming from the detrimental impacts of abiotic stressors, leading to a concerning decline in output. Salinity stress is one of the major factors that limiting the growth and productivity of pea. However, biochar amendment in soil has a potential role in alleviating the oxidative damage caused by salinity stress. The purpose of the study was to evaluate the potential role of biochar amendment in soil that may mitigate the adverse effect of salinity stress on pea. The treatments of this study were, (a) Pea varieties; (i) V1 = Meteor and V2 = Green Grass, Salinity Stress, (b) Control (0 mM) and (ii) Salinity (80 mM) (c) Biochar applications; (i) Control, (ii) 8 g/kg soil (56 g) and (iii) 16 g/kg soil (112 g). Salinity stress demonstrated a considerable reduction in morphological parameters as Shoot and root length decreased by (29% and 47%), fresh weight and dry weight of shoot and root by (85, 63%) and (49, 68%), as well as area of leaf reduced by (71%) among both varieties. Photosynthetic pigments (chlorophyll a, b, and carotenoid contents decreased under 80 mM salinity up to (41, 63, 55 and 76%) in both varieties as compared to control. Exposure of pea plants to salinity stress increased the oxidative damage by enhancing hydrogen peroxide and malondialdehyde content by (79 and 89%), while amendment of biochar reduced their activities as, (56% and 59%) in both varieties. The activities of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) were increased by biochar applications under salinity stress as, (49, 59, and 86%) as well as non-enzymatic antioxidants as, anthocyanin and flavonoids improved by (112 and 67%). Organic osmolytes such as total soluble proteins, sugars, and glycine betaine were increased up to (57, 83, and 140%) by biochar amendment. Among uptake of mineral ions, shoot and root Na+ uptake was greater (144 and 73%) in saline-stressed plants as compared to control, while shoot and root Ca2+ and K+ were greater up to (175, 119%) and (77, 146%) in biochar-treated plants. Overall findings revealed that 16 g/kg soil (112 g) biochar was found to be effective in reducing salinity toxicity by causing reduction in reactive oxygen species and root and shoot Na+ ions uptake and improving growth, physiological and anti-oxidative activities in pea plants (Fig. 1).Figure 1A schematic diagram represents two different mechanisms of pea under salinity stress (control and 80 mM NaCl) with Biochar (8 and 16 g/kg soil).

Greenhouse gas mitigation and soil carbon stabilization potential of forest biochar varied with biochar type and characteristics

Biochar is increasingly used in climate-smart agriculture, yet its impact on greenhouse gas (GHG) emissions and soil carbon (C) sequestration remains poorly understood. This study examined biochar-mediated changes in soil properties and their contribution to C stabilization and GHG mitigation by evaluating four types of biochar. Soil carbon dioxide (CO2) and nitrous oxide (N2O) emissions, soil chemical and biological properties, and soil organic carbon (SOC) mineralization kinetics were monitored using greenhouse, laboratory, and modeling experiments. Three pine wood biochars pyrolyzed at 460 °C (PB-460), 500 °C (PB-500), 700 °C (PB-700), and one pine bark biochar from gasification at 760 °C (GB-760) were added into soil at 1 % w/w basis. Soils amended with biochar were used to cultivate sorghum for three months in a greenhouse, followed by three months of laboratory incubation. Data obtained from laboratory incubation was modeled using various statistical approaches. The PB-500 and PB-700 reduced cumulative N2O-N emissions by 68.5 % and 73.9 % and CO2 equivalent C emissions by 66.9 % and 72.4 %, respectively, compared to unamended control. The N2O emissions were positively associated with soil nitrate N, available P, and biochar ash content while negatively associated with SOC. The CO2 emission was negatively related to biochar C:N ratio and volatile matter content. Biochar amended soils had 49.2 % (PB-500) to 87.7 % (PB-700) greater SOC and 22.9 % (PB-700) to 48.1 % (GB-760) greater sorghum yield than the control. While PB-700 had more saprophytes than the control, the GB-760 yielded a greater yield than biochars prepared by pyrolysis. Microbial biomass C was 7.23 to 23.3 % greater in biochar amended soils than in control. The double exponential decay model best explained the dynamics of C mineralization, which was associated with initial soil nitrate N and available P positively and total fungi and protozoa biomass negatively. Biochar amendment could be a climate smart agricultural strategy. Pyrolysis pine wood biochar showed the greatest potential to reduce GHG emissions and enhance SOC storage and stability, and gasification biochar contributed more to SOC storage and increased crop yield.

Fuel Characteristics and Phytotoxicity Assay of Biochar Derived from Rose Pruning Waste.

The aim of this study was the characterization and evaluation of applicability as a soil amendment of biochar derived from rose pruning waste at different pyrolysis temperatures (200-500 °C) and process durations (20-60 min). The biochar properties were compared to the raw material. The biochars produced at 300 °C for 40 and 60 min demonstrated the best fuel properties. These variants showed high energy gain rates (77.6 ± 1.5% and 74.8 ± 1.5%, respectively), energy densification ratios (1.35 ± 0.00 and 1.37 ± 0.00, respectively), high heating values (24,720 ± 267 J × g-1 and 25,113 ± 731 J × g-1, respectively), and relative low ash contents (5.9 ± 0.5% and 7.1 ± 0.3%, respectively). Regarding fertilizer properties, such as pH value, ash content, heavy metal content, and pollutant elution, the biochars showed better qualities than the raw material. All tested biochar did not exceed the permissible values for heavy metals, including Cr, Cd, Ni, and Pb. The most optimal properties for soil amendments were noted for biochar variants of 400 °C for 40 min, 450 °C for 20 min, and 500 °C for 20 min. Generally, biochars produced at temperatures ≥400 °C did not inhibit root elongation, except for the material produced at 450 °C for 60 min (4.08 ± 23.34%). Biochars obtained at ≥300 °C showed a positive impact on seed germination (86.67 ± 18.48-100 ± 24.14%).

Biochar obtained from eucalyptus, rice hull, and native bamboo as an alternative to decrease mobility of hexazinone, metribuzin, and quinclorac in a tropical soil.

Mobile herbicides have a high potential for groundwater contamination. An alternative to decrease the mobility of herbicides is to apply materials with high sorbent capacity to the soil, such as biochars. The objective of this research was to evaluate the effect of eucalyptus, rice hull, and native bamboo biochar amendments on sorption and desorption of hexazinone, metribuzin, and quinclorac in a tropical soil. The sorption-desorption was evaluated using the batch equilibrium method at five concentrations of hexazinone, metribuzin, and quinclorac. Soil was amended with eucalyptus, rice hull, and native bamboo biochar at a rate of 0 (control-unamended) and 1% (w w-1), corresponding to 0 and 12 t ha-1, respectively. The amount of sorbed herbicides in the unamended soil followed the decreasing order: quinclorac (65.9%) > metribuzin (21.4%) > hexazinone (16.0%). Native bamboo biochar provided the highest sorption compared to rice hull and eucalyptus biochar-amended soils for the three herbicides. The amount of desorbed herbicides in the unamended soil followed the decreasing order: metribuzin (18.35%) > hexazinone (15.9%) > quinclorac (15.1%). Addition of native bamboo biochar provided the lowest desorption among the biochar amendments for the three herbicides. In conclusion, the biochars differently affect the sorption and desorption of hexazinone, metribuzin, and quinclorac mobile herbicides in a tropical soil. The addition of eucalyptus, rice hull, and native bamboo biochars is a good alternative to increase the sorption of hexazinone, metribuzin, and quinclorac, thus, reducing mobility and availability of these herbicides to nontarget organisms in soil.

Comparative analysis and prediction of cation exchange capacity via summation: influence of biochar type and nutrient ratios

IntroductionEnhancing soil cation exchange capacity (CEC) is of paramount importance for sustainable agriculture and ecosystem health. This study investigated the pivotal role of biochar in altering soil CEC and challenges conventional assumptions about universal effects of biochar application.MethodsContrasting biochar types, one with a low ash content of 4.4% (switchgrass-derived biochar, SGB) and the other with a high ash content of 45.9% (poultry litter-derived biochar, PLB) were used. Two experiments treated with increasing biochar application rates were conducted: one without plants and the other grown with ryegrass. Effective CEC (summation method) was determined by two extraction methods: Mehlich-3 (M3) and ammonium acetate (AA).Results and discussionThe SGB decreased CEC by 27% on average (from both experiments) from the lowest to the highest rate of biochar application, while the PLB significantly increased CEC by 91%. This highlights the critical role of biochar properties in influencing CEC dynamics. In the second experiment, ryegrass cultivation revealed the greater importance of the calcium and magnesium/potassium ratio ([Ca+Mg]/K) in the soil CEC than CEC only for plant growth in biochar-amended soils. The ratios for optimum ryegrass production ranged from 82‒86 (M3) and 69‒74 (AA), which was translated to 88:11:1 Ca:Mg:K percent base saturation ratios. Moreover, predictive models for estimation of soil CEC after biochar application were successfully developed based on initial soil and biochar CEC. However, M3 was more reliable than AA for such predictions mainly because it was more successful in predicting nutrient availability from biochar. These models offer a promising tool for informed soil management decisions.ConclusionThis research emphasizes the importance of biochar feedstock, elucidates nutrient ratio effects on plant growth, and provides a practical means to anticipate soil CEC changes post-biochar application.

Significance of pyrolytic temperature, application rate and incubation period of biochar in improving hydro-physical properties of calcareous sandy loam soil

Biochar is increasingly recognized for its ability to enhance hydro-physical properties of soil, offering promising solutions for improving soil structure, water retention, and overall agricultural productivity. In this study, sandy loam soil was amended at different rates (0, 15, 30, and 60 t ha−1) of biochar produced from olive pomace (Jift) at different pyrolysis temperatures (300, 400, 500, and 600 °C), and incubated for 30, 60, and 90 days. The biochar-amended soils were collected for analysis after each incubation period for infiltration rate, aggregate stability, soil water retention, water repellency, and penetration resistance. At 300 °C, aggregate stability increased with biochar amendments; the highest value (65%) was after 60 days of incubation. At other pyrolysis temperatures, aggregate stability decreased, or no effect of temperature was observed. Also, at 300 °C, the infiltration rate was decreased with biochar application and the lowest value of (0.14 ml/min) was at 90 days of incubation. At other pyrolysis temperatures, the infiltration rate was increased with increased biochar application rate. Water retention was increased with biochar application at 300 °C; however, biochar application did not affect water retention at other pyrolysis temperatures. These results strongly suggest the improvement of soil physical and hydraulic properties following the addition of biochar amendment. Overall, biochar had positive effects on hydro-physical properties. The biochar produced at 300 °C pyrolysis temperature was the most beneficial to agriculturally relevant hydraulic conditions. However, field assessments are necessary to evaluate the long-term effects of biochar on hydro-physical properties.

Biochar has positive but distinct impacts on root, shoot, and fruit production in beans, tomatoes, and willows

Positive relationships have been documented between the amount of biochar added to soils and various aspects of plant growth and fertility such as root, shoot, and fruit production. However, these effects depend on biochar source materials, soil characteristics and species of plant examined. This makes it impossible to systematically compare and generalize findings across previous studies that have used different soils and biochar. We conducted a novel investigation to assess the effects of a single source of biochar (hazelnut wood), in a constructed organic soil, on the different plant tissues in three functionally distinct species: tomatoes (Solanum lycopersicon), green beans (Phaseolus vulgaris), and willow (Salix sp.). Five levels of biochar soil amendment were assessed: 0% (control), 3, 9, and 26% by dry weight. We found a highly significant positive relationship between biochar concentration and total plant biomass (roots + shoots + fruits) in all species, with no significant difference in total biomass response among species. Fruit production increased with increased biochar in both beans and tomatoes. However, tomatoes exhibited significant differences in response among plant tissues; fruit production and shoot biomass increased significantly with biochar, but root tissue did not. Bean germination success increased significantly with biochar concentration. Date of first flowering was earlier with increasing soil biochar in beans but not in tomatoes. Control over both sources of biochar and soil composition in this experiment enables us to conclude that biochar addition can have different impacts on different plants and, in some cases, species-specific impacts on different plant tissues and other measures of fertility. Our results are contrary to prior research that found inhibiting effects of biochar at levels comparable to our 26% treatment. Biochar impacts on soil properties such as CEC and percent base cation saturation do not explain our findings, leading us to conclude that microbial interaction with biochar is an important factor that may explain the positive impacts of soil biochar on plant fertility observed. Further research that repeats this experiment in other soil types, with other biochar sources, and with other plant species is necessary to determine the generalizability of these important findings.

Influence of Date Palm-Based Biochar and Compost on Water Retention Properties of Soils with Different Sand Contents

Generally, soils of arid and semi-arid regions have low water retention properties due to high sand and low organic carbon contents. This study aimed at quantifying the effect of date palm-based organic amendments (OAs) on the water retention properties of two soils (sandy loam and silty loam), as well as the influence of sand supplementation (0.5–2 mm) on the magnitude of the effect of OAs. Different grain size distributions were obtained by adding sand to natural soils. For this purpose, sand was added to the two soils (1/3 and 2/3) and different soil-OA combinations were tested at a dose of 3% by mass: compost alone, biochar alone and a mixture of biochar and compost (50:50 in mass), in addition to unamended control soils. Soil water contents were measured at nine matric potentials ranging from the saturation to the permanent wilting point. Biochar was more efficient than compost at improving soil water retention. The effect of organic amendments on water retention increased with sand content. In most cases, soil water content values were significantly higher for biochar-amended soils than for unamended or compost-amended soils. The weakness of the effect of compost addition (if alone) was probably due to its properties and notably its high mineral content and electrical conductivity. Soil sand supplementation led to higher differences between the OA-amended soils and unamended soils. Changes in available water capacity reached +26% and +80% in a sandy loamy soil enriched with 2/3 sand and amended with compost and with biochar, respectively, compared to the unamended soil. These results show that sand content (and more generally, soil texture) influences the effect of OA application. Thus, the application of biochar from date palm residues in soil seems to be an effective solution to improve the water retention properties of coarse textured soils and contribute to optimizing the use of water resources in irrigated areas.

Effect of Biochar Type and Amendment Rates on Soil Physicochemical Properties: Potential Application in Bioengineered Structures

Abstract Biochar has recently gained attention as a potential soil amendment for its usage in bioengineered structures, e.g., landfill cover system, green slopes, green corridor, etc., that usually comprises compacted soil with vegetation. In literature, many studies have explored the effect of biochar sourced from plant (agri-residues, wood)- and animal-based biomass on physicochemical properties of soil suitable for agricultural application. However, systematic study rarely has been conducted for soil suitable for bioengineered structures, and contradictory results have been reported. The objective of the present study is to explore the effects of biochar produced from different feedstock types (poultry litter, water hyacinth, and sawdust) on physicochemical properties of soil for bioengineered structures application. The results revealed that the amendment of biochar increased the liquid limit (14–52 %), plastic limit (PL, 2–66 %), optimum moisture content (OMC, 4–50 %), pH (29–59 %), cation exchange capacity (20–428 %), and water absorption capacity (12–94 %), whereas it decreased the maximum dry density (7–17 %), specific gravity (3–17 %), and shrinkage area ratio (SAR, 22–57 %) of the soil. Among the different biochar types tested, water hyacinth biochar (WHB) exhibited the highest increase in PL, OMC, and pH, and decrease in specific gravity and SAR of the soil after amendment, whereas poultry litter biochar showed the lowest variation of the same. These changes in the soil physicochemical properties after biochar amendment are likely attributed to the presence of intrapores and active chemicals in biochar, which are highly dependent on feedstock types. The findings of the present study could be useful in understanding the hydro-mechanical and plant interaction of biochar-amended soil (BAS), and potential implementation of BAS in bioengineered structures.

Biochar mitigates the mineralization of allochthonous organic matter and global warming potential of saltmarshes by influencing functional bacteria

Saltmarshes are suffering from severe degradation due to anthropogenic activities, leading to the loss of blue carbon and greenhouse gas (GHG) emissions. Given the significant potential of biochar in mitigating climate change, adding biochar to saltmarshes would alleviate this situation. This study investigated the effects of different biochar (made from Spartina alterniflora, corn straw, and Laminaria japonica) and their aged biochar on the carbon fraction contents, GHG emissions, and microbial community structure of saltmarsh soils with allochthonous organic matter (Enteromorpha prolifera) addition. After 60 days of incubation, total organic carbon (TOC) loss and global warming potential (GWP) of biochar-amended soils were reduced by 67.29–124.33% and 4.91–123.24%, respectively (p < 0.05). Biochar reduced the proportion of labile carbon (dissolved organic carbon (DOC) and microbial biomass carbon (MBC)) in organic carbon by 61.92–86.15% (p < 0.05). In addition, biochar reduced the relative abundance of specific functional bacteria (inc. cellulolysis, aromatic compound degradation, and xylanolysis) involved in organic carbon decomposition by 20.02–37.82% (p < 0.05). These results suggest that even in the presence of high levels of liable organic matter, the application of biochar to saltmarshes has a sustained effect in promoting carbon accumulation and reducing GHG emissions, and this effect is regulated by a decrease of functional bacteria associated with carbon metabolism. Therefore, the in situ study of biochar on restoring carbon sink function of saltmarshes is proposed for practical engineering in future.Graphical

Mitigation of Fugitive Gas Emissions from Landfill Using Biochar-Amended Soil Cover and Its Geotechnical Characterization

Landfills with gas collection systems often struggle to capture fugitive emissions through the final soil cover, leading to significant environmental challenges. Considering recent major landfill fires in India, methane gas emissions have been identified as the primary cause. This research explores the potential of biochar-amended soil covers as an alternative solution to mitigate fugitive emissions. Various percentages of biochar were added to the soil collected from a landfill site in Vilholi, Maharashtra, India. Geotechnical testing assesses compaction characteristics, hydraulic conductivity, and shear strength. Amendment improves the compaction characteristics of soil cover. The decreased hydraulic conductivity with amendment indicates improved water retention. The interlocking between soil and biochar and the specific type of biochar influences the strength gained. The column setups containing different percentages of amended soil showed reduced emissions. The improved geotechnical properties and reduced fugitive emissions demonstrate the potential for biochar-amended soil covers to enhance landfills' stability.

Effects of Biochar Amendment on N2O Emissions from Soils with Different pH Levels

Biochar application has the potential for mitigating N2O emissions from agricultural soils and has been suggested as a management practice to ameliorate soil fertility and increase crop productivity. Nevertheless, the influence of biochar addition on N2O emissions from soils with different pH levels is not yet clear, which results in a poor understanding of the mechanisms regarding biochar application to soil N2O mitigation. A 40-day incubation experiment was carried out in the present study to investigate the impact of biochar on N2O emissions from soils with different natural pH. Four treatments (control, nitrogen fertilizer application, biochar amendment, and N plus biochar amendment) were set up separately in soils with three different natural pH levels (acidic vegetable soil, neutral rice soil, and alkaline soil). Our results showed that adding biochar significantly decreased N2O emissions by 20.8% and 47.6% in acidic vegetable soil for both N and no N addition treatments, respectively. For neutral and alkaline soils, the reduction of N2O emissions by biochar amendment was only significant for N addition treatments in alkaline soil. Soil pH and NO3−-N concentration were significantly affected by biochar amendment (soil pH increased by 1.43–1.56, 0.57–0.70, and 0.29–0.37 units for acidic vegetable soil, neutral rice soil, and alkaline soil, respectively). Thus, biochar amendment could be used as an effective management practice for mitigating N2O emissions from acidic and alkaline soils.

Poultry litter biochar soil amendment affects microbial community structures, promotes phosphorus cycling and growth of barley (Hordeumvulgare)

Phosphorus (P) is a non-replaceable, finite component of fertilizers. The imbalanced resource distribution and possible depletion of P impose challenges on current crop production worldwide. The aim of this study was to assess the impact of poultry litter biochar on plant growth and P mobilizing capability of the microbiome in comparison to a mineral fertilizer application. Spring barley (Hordeum vulgare) was grown in microcosms using a P-limited soil, fertilized with 0 (control), 50 (fertilizer) kg P ha−1 or a poultry litter biochar amendment (biochar, 2% w/w). Biochar amended rhizospheres had significantly higher phosphonate-utilizing bacteria, phoC and phoD gene (acid and alkaline phosphatase) copy numbers and improved P availability. Spring barley dry matter yields were significantly higher for biochar and fertilizer over control; however, P uptake with biochar was higher than with fertilizer. Furthermore, biochar had higher arbuscular mycorrhizal colonization and significantly raised soil pH. Fingerprint-analysis showed significant differences between all treatments for bacterial and fungal communities. 16S rRNA gene-based sequencing analysis revealed increased relative abundance of the phyla Actinobacteriota and Chloroflexi in biochar compared to control, potentially contributing to the ameliorated plant growth conditions. Pearson correlations of both phyla was positive with a range of P cycling variables as well as Morgan's P but negative with acid phosphatase activity. FAPROTAX analysis revealed positive correlations of aromatic compound degradation with phoC and phoD gene abundance, highlighting a possible link between biodegradation and P release. In conclusion, poultry litter biochar could potentially replace mineral P fertilizer for sustainable plant growth in P depleted soil environments.

Appraising the Effect of Biocharin Groundnuts(Arachis hypogaea L) Growth Parameters and Yield Under Screen House Conditions

Biochar soil amendment is known to suppress the effect of pathogenic fungi and favour plant resistance against soil‐borne pathogen effects. Thisstudy appraises the impact of biochar on groundnutyield planted in the slightly acidic sandy loam soil.Thestudy was done at the Nelson Mandela African Institution of Science and Technology (NM-AIST) screen house, where groundnuts wereplanted in the 2L pots filled with soil mixed with biochar at different rates (2.5%, 5% and 7.5%)in April 2022. Groundnut’sgrowth parameters weremanaged by measuring shoot lengthand root length, counting the number of leaves and taking leaf area once every week from the second week after planting to harvesting,where its yield was also measured. Analysis of variance showed a significant (P &lt; 0.05) increase in groundnut growth parameters and yield when 5% Biochar was used. There was a strong positive correlation between biochar and some groundnut growth parameters. No significant (P &lt; 0.05) differencewas observed between Biochar and groundnut growth parameters and yield when 2.5% biochar was used. A slightly weak negative correlation was observed when a 7.5% Biocharrate was used. Biochar-amended soils indicated a dramatic increase in soil pH, CEC, Mn, P, K, Ca, B, Zn and Si. The current study indicates that the utilization of 5% maize cob biochar, pyrolyzed at 500°C, in acidic sandy loam soil,can lead to maximum enhancement in soil physical and chemical properties, as well as groundnut growth and yield parameters.

Biocha Soil Amendment: Effect on Soil, Crop Performance, and Diseases Resistance

One of the main challenges facing developing countries is an ever-increasing gap between population growth and food supply. Diseases, insects, and weeds decrease the production of crops worldwide by 36%. Hence, control of crop pests contributes to increased crop production. Organic amendments to the soil have direct impacts on crop productivity and plant health as it enhances soil fertility, water, and nutrient retention and plant disease defense mechanisms. Biochar is an important organic amendment. It is produced by the pyrolysis process, whereby organic substances are broken down at higher temperatures in low oxygen conditions. Biohar improved soil nutrient availability and water retention capacity, and induced plant resistance against broad ranges of plant pathogenic organisms including fungi, nematodes, and bacteria. Biochar soil amendment also enhances root-associated microbes such as flavobacterium and arbuscular mycorrhizae. Biochar amendments can increase soil essential nutrients for crop productivity and suppress plant pathogens. Suppression of plant pathogens is attributed to the stimulation of beneficial soil microbes, providing nutrients, and inducing plant defense. The objectives of the review are to depict the importance of biochar soil amendment on crop performance, disease resistance, and soil properties.

Effective mitigation of Cadmium contamination in soil through Sawdust Biochar application

Cadmium (Cd) contamination in soil is a serious environmental concern, and this study examines the effectiveness of sawdust biochar in reducing Cd contamination over three months. The study explores different sawdust biochar application rates and their effects on the amount of extractable Cd in the soil. According to the study, sawdust biochar has a high potential for addressing Cd pollution. Importantly, over the duration of the investigation, extractable Cd concentrations gradually decreased as a result of the use of biochar. In particular, compared to lesser application rates of 2.5% and 1.25%, the highest biochar application rate (5%) resulted in a significant reduction in cumulative leachable Cd content. Additionally, compared to the control group, all biochar-amended soils showed considerably decreased cumulative leachable Cd levels. The leachate study demonstrated the time-dependent efficiency of biochar in lowering Cd concentrations, with Cd concentration declining from 14 mg/L in August 2023 to a meager 0.004 mg/L in October 2023. Diffusion within the porous structure of biochar was determined to be the main process underlying heavy metal adsorption. However, the observed decrease in the effectiveness of heavy metal removal with biochar may be explained by surface oxidation, which creates a greater number of accessible adsorption sites. Furthermore, the soil's capacity to absorb Cd2+ was greatly improved by the raised pH brought on by biochar application, further enhancing Cd removal. The study also showed the importance of pyrolysis temperature on biochar characteristics, with higher temperatures greatly improving Cd adsorption capability. This study's findings highlighted the significant potential of sawdust biochar as a powerful technique for reducing soil Cd pollution. These results highlighted the potential of biochar for Cd remediation and crucial role that pyrolysis temperature plays in determining biochar's characteristics and adsorption capacity.

Towards Electrobiofuels: Economics and Environmental Impacts

Our changing climate necessitates a transition to biomass-based hydrocarbon fuels to power aviation, shipping, and long-haul trucks that service essential supply chains to deliver food, textiles, and other consumer goods including electronic devices. To accomplish this transition, renewable energy systems are needed that efficiently deconstruct biomass and superimpose non-carbon emitting electrical energy with bioenergy to increase output energy in liquid fuels. Fast pyrolysis and electrocatalytic hydrogenation (py-ECH) is a technology sequence that first converts biomass into a liquid, known as bio-oil, which is then electrocatalytically hydrogenated to stabilize its properties. Products formed after py-ECH include linear and branched polyols, tetrahydrofurans, and alkyl cyclohexanols. Evidence of lignin oligomer cleavage has also been observed, as has the subsequent appearance of monomeric cyclohexanols. Building on these encouraging results, the commercialization potential of py-ECH was determined by economic analysis and life cycle assessment. These analyses co-locate ECH after pyrolysis at decentralized biomass upgrading depots, with the aim of stabilizing pyrolysis bio-oil for subsequent transport to centralized hydroprocessing refineries. The results of these analyses suggest that electrocatalytic hydrogenation is the keystone technology for coupling non-carbon emitting electrical energy with biomass carbon to generate a greater amount of liquid fuel than otherwise possible. A pathway to liquid fuel less than $3 per gallon of hydrocarbon equivalent fuel can be established, especially if renewable electricity is provided at low cost. Finally, “electrobiofuels” can be made with negative net carbon emissions with well-managed agriculture, biochar soil amendment, and when renewable electricity powers ECH.