Search Results (277)

Leaf blight and fruit rot caused by Phomopsis vexans are critical issues for eggplant crops. Our study evaluated the biochar amendment, alone and in combination with a foliar spray of silicon dioxide nanoparticles (SiO₂-NPs), on plant performance and disease development. Fungal infection reduced plant growth, with a 22% decline in plant height and a marked decrease in chlorophyll and carotenoid levels. Adding biochar plant height mitigated these effects: the highest dose (30 g) increased plant height in infected plants by 17.1% and increased pigment concentrations and POX and PPO activities. At the same time, the blight index declined. When biochar was combined with SiO₂-NPs, the improvements were more pronounced. In infected plants, the 30 g + SiO₂-NPs treatment produced substantial improvement in plant height (+31.3%) and shoot biomass and restored chlorophyll and carotenoid contents by 63% and 28.1%, respectively. This treatment also produced the lowest blight index and the strongest enzymatic responses. Principal component analyses discriminated treated plants from infected ones. These findings indicate that biochar and SiO₂-NPs can jointly enhance plant resilience to P. vexans infection, reducing its negative impact. Full article

Cadmium (Cd) contamination in paddy soils threatens rice production and food safety. This study investigated the effects of manganese (Mn)-enriched biochar on soil Cd immobilization and Cd accumulation in rice using a pot experiment with Cd-contaminated soil. Unenriched biochar and Mn-enriched biochar prepared from rice straw were applied at two rates (0.5% and 1.0%). Both biochar types significantly increased soil pH and organic matter and promoted the transformation of Cd from labile fractions to more stable residual forms, thereby reducing Cd bioavailability. As a result, Cd accumulation in rice tissues, including straw and brown rice, was significantly reduced. Correlation analysis further indicated that increased soil pH was associated with reduced Cd mobility and plant uptake. Mn-enriched biochar markedly increased Mn accumulation and uptake efficiency in rice while decreasing Cd uptake efficiency, indicating a strong antagonistic interaction between Mn and Cd in the soil–plant system. Notably, a low application rate of Mn-enriched biochar (0.5%) achieved Cd reduction effects comparable to those of a higher dose of unenriched biochar (1.0%). These results suggest that Mn-enriched biochar is an effective and potentially cost-efficient strategy for reducing Cd bioavailability in paddy soils and mitigating Cd accumulation in rice. Full article

Microplastic pollution in farmland soils has emerged as a global concern due to its potential to degrade soil health, inhibit crop growth, and enter the food chain. However, effective and environmentally friendly remediation strategies remain limited, particularly regarding the use of biochar to mitigate polyethylene microplastic (PE-MP) stress in agroecosystems. This study investigates whether tobacco stalk biochar (TSB) can alleviate PE-MPs stress in rice seedlings. A two-factor pot experiment was conducted to systematically analyze the responses of soil physicochemical properties, rice growth indicators, and antioxidant enzyme activities to the combined application of varying concentrations of PE-MPs (0, 0.5%, 1%, and 2% (w/w)) and TSB (0, 3%, 6%, and 9% (w/w)). The results show that TSB significantly increased soil pH and organic matter content, effectively mitigating the decline in available nitrogen, phosphorus, and potassium caused by PE-MPs (e.g., under the M3B3 treatment, available nitrogen and phosphorus contents increased by 68.7% and 226%, respectively, compared with those under the M3B0 treatment). Under low-concentration PE-MP (0.5%) stress, an appropriate amount of TSB (3%) resulted in the highest rice germination rate, vigor index, and stress tolerance index, while significantly inducing the activities of superoxide dismutase (SOD) and catalase (CAT) to alleviate oxidative damage. However, high-concentration combinations of TSB and PE-MPs exhibited an antagonistic effect. In conclusion, tobacco stalk biochar can synergistically mitigate microplastic stress on rice through multiple pathways, with its remediation effects exhibiting significant dose dependence and interactive complexity. These findings provide a theoretical and technical basis for the ecological remediation of microplastic pollution in farmland. Full article

In this study, pristine biochar (BC1) and magnesium-modified biochar (BC2) were prepared from corn straw. Different nitrogen deposition intensities (0, 8, 30, and 50 kg N/(ha·yr)) were simulated by adding NH₄NO₃ solution. A laboratory incubation experiment was conducted to investigate the effects of biochar addition and N deposition on CO₂ emissions, CH₄ uptake, and microbial community structure in soils from a temperate mixed conifer–broadleaf forest. The results showed that BC1 significantly increased cumulative CO₂ emissions (p < 0.05), while no significant difference was observed between BC2 and the control. N deposition had no significant effect on CO₂ emissions. Biochar addition significantly promoted cumulative CH₄ uptake (p < 0.05), with BC2 exhibiting a stronger promoting effect than BC1. In contrast, N deposition significantly inhibited CH₄ uptake (p < 0.05) in a dose-dependent manner. Spearman’s correlation analysis revealed that cumulative CO₂ emissions were significantly or highly significantly negatively correlated with the relative abundances of Elusimicrobiota, Actinomycetota, Chloroflexota, Planctomycetota, Acidibacter, Bacillus, Paenibacillus, Acidothermus, and Mycobacterium, and significantly positively correlated with Bacteroidota, Bdellovibrionota, Pseudomonadota, Devosia, and Mesorhizobium. Cumulative CH₄ uptake was highly significantly positively correlated with the relative abundance of Bacteroidota and significantly negatively correlated with Chloroflexota, Candidatus_Eremiobacterota, and Mycobacterium. These findings demonstrate that N deposition has no significant impact on soil CO₂ emissions but significantly inhibits CH₄ uptake, while magnesium-modified corn straw biochar promotes CH₄ uptake without substantially increasing CO₂ emissions, highlighting its promising application potential. Full article

Micronutrient addition to soil is crucial for improving crop yield. Within the framework of the circular economy, it is necessary to seek more efficient fertilizers. This would reduce fertilizer consumption while serving as a strategy to mitigate the negative effects of climate change. This study proposes the combined use of a traditional source of a Zn fertilizer (ZnSO₄) together with wood biochar to improve lettuce (Lactuca sativa L.) crop yield. An experiment was designed in which a dose of 8 mg Zn kg⁻¹ as ZnSO₄·7H₂O was added to Cambisol soil, mixed with or without biochar (5%), for lettuce growth. Among other soil properties, Zn bioavailability, microbial biomass, and available water were monitored in the soil, while photosynthetic pigments, Zn content, and biomass production were determined in plants. All treatments increased plant biomass production. Biochar treatments (biochar and biochar/ZnSO₄) increased fresh biomass by 324%, while ZnSO₄ addition resulted in a 158% increase in lettuce yield. This can be due to several factors, such as biochar being a C source, the improvement of soil water content after biochar addition, and the increase in Zn leaf content in all treatments with respect to the control soil. All of these likely had a positive effect on photosynthesis. This is corroborated by the increase in total chlorophyll, chlorophyll, and carotenoids in the treatments with ZnSO₄, biochar/ZnSO₄, and biochar. The application of biochar alone increased this property by more than 168%, with a positive impact on soil quality. Our research demonstrates that it is possible, in some cases, to prepare fertilizers combining ZnSO₄ and biochar, leading to increased plant Zn uptake and improved crop yield. Full article

Further understanding is needed regarding how biochar, over the long term, influences N₂O release and the associated communities of nitrifiers and denitrifiers in paddy soils. This field study examined the responses of these microbial communities to biochar applied for different durations (2016 or 2023) and at different doses (15 or 45 t·ha⁻¹), alongside a control (CK) without biochar addition. Relative to the control (CK), all biochar amendments led to a comprehensive enhancement of soil physicochemical properties. However, their impacts on N₂O fluxes diverged: cumulative emissions rose by 18.44% under the high-rate (45 t·ha⁻¹), first-year application (NB45) in 2023, but were suppressed across all other biochar treatments. Microbial community composition diverged markedly between treatment chambers, with the abundances of Nitrospira and Chloroflexota showing distinct patterns. In 2016, the two bacterial species exhibited significantly high abundance proportions, with maximum shares of 23.55% (2016, 45 t·ha⁻¹) and 12.16% (2016, 45 t·ha⁻¹), the most abundant in nitrification and denitrification, respectively, which influenced the certainty of changes in the microbial community structure. Biochar enhances nitrogen metabolism in nitrifying microorganisms but inhibits denitrification processes, with the biochar applied in 2023 having a remarkable effect. Overall, biochar application effectively enhances soil physicochemical properties, mitigates N₂O emissions over the long term, and modulates the community structure and functional traits of nitrifying and denitrifying microorganisms. These combined effects contribute to promoting environmental security for sustainable development within agricultural production systems while reducing the carbon footprint. Full article

Desertification in Mediterranean drylands threatens food security. This study evaluated biochar–compost amendments on drought-affected sandy–calcareous soils, focusing on carbon (C) and nitrogen (N) dynamics. Laboratory soil incubations revealed that biochar reduced C mineralization, aiding long-term storage, but also decreased N mineralization, signaling potential short-term immobilization. However, leaching experiments showed that incorporating 2%, 5%, 10%, and 20% biochar into compost significantly reduced C losses by 22, 26, 36, and 48%, respectively, and N losses by 37, 67%, 45%, and 65%, respectively. In water-stressed lettuce trials, the use of compost alone could only yield 30% of the yield obtained in unstressed lettuce treated with compost. While the addition of 2–5% biochar to compost enabled the conservation of 44–45% of the yield of unstressed lettuce, a 10% biochar amendment doubled this number (88%). Nonetheless, a higher dose of 20% biochar in the compost offered no additional benefit with 84% of the yield of unstressed lettuce amended with compost. These findings position biochar–compost as a key strategy to enhance soil fertility and water-use efficiency. To counteract short-term N immobilization, the study recommends further investigation of early application combined with supplemental fertilization or fractionated biochar supply (over 2–3 years). Ultimately, tailoring biochar formulations to specific local conditions is essential to balance immediate crop productivity with long-term soil health. Full article

Plastics have emerged as a significant pollutant, posing a serious threat to the sustainability of the soil ecosystem and food security because of their long-term persistence, resilience, and robustness under different environmental conditions. The present investigation explored the impact of different doses of polypropylene (PP) on lentil plants and attenuation of the adverse impacts of PP by the application of pineapple fruit peel biochar (PBC). Lentil (Lens culinaris) plants exposed to PP treatment reduced morphological traits and relative water contents, reflecting photosynthetic injuries, a rise in lipid peroxidation, and electrolyte leakage. Utilization of PBC derived from waste biomass enhanced the growth attributes of lentils and alleviated PP-incited oxidative stress impacts. Polypropylene stress enhanced oxidative stress and increased enzymatic and non-enzymatic antioxidant variables in lentil plants. Antioxidant enzymes superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, and glyoxalase enzymes were markedly upregulated in lentil after PBC amendment in PP3-treated soil. There was a significant reduction in methylglyoxal content by the activities of glyoxylase enzymes, minimizing the negative impacts of PP. Therefore, soil amendment with PBC protected lentil plants from PP-instigated oxidative disruption by modulating activities of antioxidant defense and glyoxalase system. Production of PBC from biomass wastes results in a safe, cost-effective, and ecofriendly material that can be used at the industrial level for the cultivation of crops in PP-contaminated soil. The novelty of the present research lies in promoting soil management practices and fostering our understanding of waste materials reutilization as renewable assets to combat the ecological implications of plastic pollution, and it emphasizes the treatment of plastic wastes with other waste materials and their practical applications to overcome plastic pollution. Full article

Cotton (Gossypium spp.) is the most important fiber crop for the textile industry globally. Abiotic stresses, including drought, have become prevalent in affecting cotton production worldwide. There is a shortage of studies on the use of biochar as a soil amendment in the semi-arid and arid Southwest and West U.S. Cotton Belt to alleviate drought stress. This study was conducted to examine the effects of biochar at four application rates (0, 6.25, 12.5, and 25.0 t ha⁻¹) on cotton yield and yield components using six tetraploid cotton genotypes, including one Pima (G. barbadense L.) and five Upland cottons (G. hirsutum L.), under well-watered (WW) and drought stress (DS) conditions in an arid region of New Mexico, USA. The six cotton genotypes consistently showed that DS at the flowering stage significantly decreased boll number (BN), boll weight (BW), and lint percentage (LP), and thereby seed cotton weight (SCW) per plant and lint weight (LW) per plant. However, Pima DP 359 RF had the lowest reduction (23–33%) in BN, SCW, and LW due to drought, while DP 2020 B3XF was the most sensitive to drought, with a 45–48% reduction in the traits. Under DS conditions, biochar at the rate of 12.5 t ha⁻¹ had the highest SCW and LW, and the lowest reduction in BN, BW, SCW, and LW due to drought, which was significantly different from the non-biochar control, and no genotype × biochar interaction was detected. However, biochar had no positive effects on cotton productivity under non-drought conditions. This study has demonstrated the positive effects of biochar on cotton yield and yield components in alleviating drought stress, laying the foundation for more follow-up studies toward its utility in cotton production in semi-arid and arid areas. Full article

Soil organic carbon (SOC) sequestration plays a vital role in sustaining soil productivity and mitigating climate change. Although biochar and charcoal-based fertilizers are known to enhance SOC sequestration, current understanding is predominantly derived from studies applying high doses. With the goal of elucidating the mechanisms through which long-term, low-dose biochar application influences SOC composition and stability, this study evaluated the long-term impacts of biochar and carbon-based fertilizers on SOC content, chemical structure, and microbial residual carbon assessed via amino sugar biomarkers. The following features are demonstrated by this study: (1) The application of biochar and carbon-based fertilizers significantly increased the contents of active organic carbon components (DOC, MBC, POC) and stable carbon components (MAOC, humic carbon) in the plow layer soil. Notably, the C50 treatment reduced the easily oxidizable organic carbon (EOC) content by 19.25% compared to the control. (2) Long-term application increased the relative abundance of aromatic functional groups in SOC, enhanced SOC decomposition resistance (as reflected by the F-index). Compared with NPK, the BBF treatment increased the F-index by 21.28% and 25.00% in the 0–20 cm and 20–40 cm soil layers. (3) The BBF treatment significantly increased both soil amino sugar content and the contribution of microbial residual carbon to SOC. Specifically, it elevated the levels of GluN, GalN, and MurN by 9.24% to 33.31% across soil layers. Fungal residual carbon constituted the dominant fraction across all treatments. In summary, the content and stability of SOC are enhanced by biochar and biochar-based fertilizers through synergistic mechanisms that involve altering its chemical composition and stimulating the accumulation of fungal residual carbon. Full article

Food security is threatened in the semiarid region of Brazil, which is susceptible to climate change and has low-fertility soils degraded by inadequate agricultural practices. This study aimed to evaluate safflower’s adaptation to the region and the benefits to the soil and crop of applying biochar and wood vinegar (WV). Biochar, pure or WV-added (Wv-biochar), was applied to the soil at doses of 3.0, 6.0, and 9.0 t ha⁻¹. Determinations performed in three harvests of safflower were plant height, number of capitula per plant, number of seeds per capitulum, mass of 1000 seeds, seed yield, and oil content. The maximum safflower yields (1818.52 kg ha⁻¹) and oil content (45.50%), and the average values of mass of 1000 seeds (35.55 g) were consistent with results reported in literature. Evidence of better performance of the variables under the effect of Wv-biochar than of pure biochar was observed, and, in general, the curves obtained showed quadratic behavior, with maximum values at intermediate doses. The seed yield and oil content achieved indicate that safflower is a promising crop for the region, particularly when more adapted genotypes and improved management practices are employed. The most pronounced effects on safflower production and oil content were observed at doses of 5 to 6 t ha⁻¹ of Biochar and Wv-biochar, which are economical and sustainable alternatives due to their use of organic waste and the benefits they provide for soil and food security. Full article

Carbonaceous amendments are widely proposed to sequester hydrophobic organic contaminants in sediments, yet their effectiveness for alkylphenolic endocrine disruptors in organic-rich freshwater systems—and its time dependence—remains poorly constrained. Here, we compared activated carbon (AC), biochar (BC), and humic compost (HC) for reducing desorption and maize phytoexposure to 4-octylphenol (4-OP) and 4-nonylphenol (4-NP) in canal sediment from the Jegrička River. Sediment was spiked (~1.1 mg kg⁻¹ 4-OP; 1.2 mg kg⁻¹ 4-NP), amended with 0.5–10% (w/w) AC, BC, or HC, and aged for up to 180 days prior to multi-step XAD-4 desorption tests. A two-compartment first-order model resolved fast- and slow-desorbing pools, while a 10-day maize (Zea mays L.) pot experiment quantified early phytoextraction and sediment–plant–loss mass balances for AC and HC treatments. The unamended sediment exhibited high operational bioavailability: ~98% of both alkylphenols were XAD-4-extractable, and 83–89% of the desorbable pool was released within 24 h. AC produced the most rapid immobilization; at 0.5–1%, it halved XAD-4-extractable fractions within weeks and reduced them to near-zero within months, whereas BC and HC achieved comparable reductions only after longer aging. Plant uptake was a minor sink: in the control, shoots accumulated ~21 µg kg⁻¹ sediment of 4-OP and 65 µg kg⁻¹ sediment of 4-NP (≈2% and 5% of the initial inventory). HC generally lowered uptake, and high AC doses kept plant burdens consistently low. Overall, amendment-enhanced sorption and sequestration dominated attenuation, with AC delivering the fastest risk reduction and HC representing a more plant-compatible amendment option. Full article

The antagonistic geochemical behaviors of cadmium (Cd) and arsenic (As) in co-contaminated soils complicate their simultaneous remediation. This study aimed to develop a synergistic immobilization strategy by converting Spirulina residue into a magnetic biochar-layered double hydroxide composite (FSRBL). The composite was applied to both acidic red and calcareous black soils, and its effects on Cd and As, immobilization efficiency, and ecotoxicity were evaluated. The results showed that FSRBL effectively transforms Cd and As from mobile fractions to stable residual forms. At a 2.5% application rate, FSRBL achieved remarkable immobilization efficiencies of 39.2% for Cd and 57.5% for As, representing effectiveness 3.55 and 5.97 times higher than that of unmodified biochar, respectively. A dose–response relationship between the application amount of FSRBL and the immobilization efficiency of As and Cd was observed and further quantified using a logistic model. The results indicate that while increased FSRBL application enhances immobilization efficiency, the marginal benefit of each additional unit diminishes as the application rate increases, demonstrating a significant diminishing marginal effect. According to the ecotoxicity assessment experiment, the soil leachate from FSRBL-amended soil remarkably decreased the ecological toxicity to rice (Oryza sativa L.). Mechanistic investigations employing SEM/TEM-EDS, XRD, and XPS revealed that the synergistic immobilization could be ascribed to the multi-component cooperation within FSRBL, which resolved the conflicting pH/Eh requirements for the immobilization of Cd and As: (1) the LDH phase efficiently immobilized As oxyanions through anion exchange and isomorphic substitution; (2) the magnetic Fe phase concurrently immobilized Cd²⁺ and As oxyanions via redox transformation and coprecipitation, resulting in the formation of precipitates such as Fe/Ca/Cd–As(V). This work demonstrates a feasible approach to upcycle biomass waste into a value-added material for sustainable remediation of Cd–As co-contaminated soil. Full article

Cement production is a significant global source of CO₂ emissions, leading to a demand for sustainable concrete alternatives. This study investigates the use of various additives to partially replace cement and assesses their effects on compressive strength and fire resistance, particularly spalling. Seven concrete mixes were tested for their initial and post-fire compressive strength, mass loss, and cracking. The cement-only reference mix (R1) achieved the highest initial strength (53.3 MPa) but experienced severe explosive spalling. In contrast, the mix with slag and polypropylene (PP) fibers (R4) offered the best balance, maintaining substantial strength after fire while completely preventing spalling. Biochar additions consistently lowered strength and increased spalling risk, whereas hydrochar notably enhanced spalling resistance, especially at higher replacement levels. The results demonstrate that sustainable additives, such as slag with PP fibers or high-dose hydrochar, can effectively improve fire safety and reduce cement use, though there is an initial trade-off in mechanical performance. Ultimately, choosing the optimal mix depends on whether environmental benefits, fire resistance, or structural strength is the highest priority. Full article

The global production of blueberries (Vaccinium corymbosum L.) has increased rapidly due to rising demand for antioxidant-rich fruits, making this crop increasingly important worldwide. Because blueberries require acidic soils, soilless systems offer a promising alternative by optimizing nutrient availability and reducing soil-related limitations. Among sustainable amendments, biochar (BC) improves water retention, porosity, and microbial activity, while wood distillate (WD), rich in bioactive compounds, can enhance plant resilience and growth. Although often used separately, their combined application may exert synergistic effects on substrate fertility and plant performance. This study investigated the effects of BC and WD, alone and in combination, on the growth, yield, and fruit quality of the ‘Cargo’ blueberry cultivar grown in a soilless system. Two distinct harvests were conducted during the growing season, and statistical analyses were performed independently for each, assessing treatment effects in relation to harvest timing. Moreover, the metabolic activity of the substrate’s microbial community was evaluated to assess the impact of the treatments. Results showed that BC application, particularly at 10%, significantly enhanced plant yield and fruit quality, increasing total phenolic content and antioxidant activity, while WD exhibited variable, dose-dependent effects on growth and biochemical traits, highlighting species-specific responses in soilless blueberry cultivation. Full article