Search Results (32,612)

Bamboo plantations are increasingly recognized as significant terrestrial carbon sinks, yet accurate estimation of biomass and carbon stocks requires species-specific, regionally validated allometric models. Bambusa emeiensis L.C.Chia & H.L.Fung (ci bamboo) is among the most ecologically and economically important clump-forming bamboo species in southwestern China, but robust multi-regional allometric models are lacking. Using destructive sampling data from 127 culms across two major production areas—Sichuan Province (n = 82) and Guizhou Province (n = 45)—we developed additive biomass and carbon storage model systems enforcing mathematical additivity via nonlinear seemingly unrelated regression (NSUR). Allometric equations used diameter at breast height (D), culm height (H), and compound variables (DH, D²H) as predictors. Regional models achieved R_a² of 0.0879–0.8320 total relative error (TRE): −0.99% to 0.04% for biomass and R_a² of 0.0923–0.8282 (TRE: −1.01% to 0.03%) for carbon storage; culm and total aboveground models attained R_a² ≥ 0.52. Organ-level carbon content (40.79%–44.46%) was significantly lower than the intergovernmental panel on climate change (IPCC) default of 50% (one-sample t-test, p < 0.01 for all organs), with Sichuan values exceeding Guizhou values (independent-samples t-test, p < 0.01), indicating that use of the default would overestimate carbon stocks by 12%–22%. Cross-regional validation revealed prediction biases of up to ±19.24% when applying single-region models outside their training area, whereas the combined model held errors within ±11.36% for biomass and ±8.49% for carbon storage. External validation using 32 independent culms from Hunan, Yunnan, and Chongqing confirmed the robustness of the combined model (TRE: −6.30% to 4.27%). A key limitation is that belowground biomass was not measured. The established models provide scientifically rigorous and practically applicable tools for regional carbon accounting of B. emeiensis plantations under China’s national greenhouse gas inventory framework and for informing sustainable bamboo management planning, and demonstrate that species- and region-specific carbon fractions are essential for accurate carbon stock assessments. Full article

The growing global energy demand and the urgent need to decarbonize the energy sector are driving the search for renewable and low-impact energy sources. Within this context, the conversion of biomass into hydrogen represents a viable pathway to sustainable energy, enabling both carbon mitigation and circular use of agricultural residues. This research focuses on the simulation of an integrated system that converts viticulture residues, vine prunings and grape stalks into biogenic hydrogen through a combination of pretreatment, gasification, and upgrading stages. The analysis of four different supply scenarios shows that the integration of prunings and stalks ensures the highest hydrogen yield (6.61·10⁵ Nm³/year of H₂) and the highest energy self-sufficiency, with 25% of produced syngas used to partially cover internal energy demand. Gasification enables the process to be carbon-negative, saving 1.18 kgCO₂eq for Nm³ of H₂ produced, and economically competitive, with a break-even price of 3.81 €/kg and a return on investment of ten years. The study aligns with the decarbonization goals of the European energy transition, promoting local and circular valorization of agro-industrial waste. Full article

Agricultural byproducts cellulose-rich (~40%) sugarcane bagasse (SCB) and rice husk (RH) wastes may be used as fiber sources in biomaterials manufacturing. The hybrid biomass fibers are two kinds of fibers that should generate a biocomposite according to the functions and physical, chemical, and mechanical properties of materials. The biocomposite was synthesized using the solvothermal method. The FeCl₃.6H₂O was dissolved in C₂H₃NaO₂ and C₆H₆O₂ and later heated at 60 °C. The SCB and RH fiber (1:1) are added with HDMA into the mixture, then placed in a Teflon stainless steel autoclave at 200 °C for 6 h. The biocomposite was employed as a green adsorbent to treat wastewater through simultaneous adsorption. The biocomposite had 2.637 mmol g⁻¹ of amine groups, which makes smaller magnetic particles and a high surface area of up to 79%. The pseudo-second-order kinetic model followed the Cu(II) and Pb(II) ions adsorption for 4 h (240 min), and the maximum adsorption capacities were 35.042 mg g⁻¹ and 67.127 mg g⁻¹, respectively, at the pH of 5. The biocomposite not only got rid of metal ions, but it also worked well to get rid of dye, total suspended solids (TSSs), and chemical oxygen demand (COD) as pollutants in wastewater. The biocomposite still worked well after being used four times. Full article

Primary succession following glacier retreat provides a natural system for testing whether soil development simply shifts fine roots along a single acquisitive–conservative axis orinstead changes the nutrient-acquisition pathway that dominates at the community level. We hypothesized a stage-dependent sequence, from substrate-limited exploration, to transient morphological capture, and finally to rhizosphere-mediated biochemical mobilization. To test this idea, we quantified fine-root morphology, absorptive-transport partitioning, anatomy, phosphatase activity, exudation, community-scale belowground structure, and soil and rhizosphere properties across woody communities representing approximately 20, 40, and 90 years since deglaciation in the Hailuogou Glacier foreland. Across succession stages, bulk density and pH declined, whereas field capacity, soil carbon, and soil nitrogen increased, indicating rapid development of the belowground resource environment. Fine-root strategies did not fall along a single acquisitive–conservative continuum. Instead, morphological nutrient capture peaked at intermediate succession: the 40-year stage had the highest specific root length, specific root area, absorptive-to-transport root length ratio, and root nitrogen concentration. In contrast, the 90-year stage showed lower specific root length but higher dry matter content, thicker cortex, greater standing fine-root biomass, larger rhizosphere volume, higher phosphatase activity, and greater area-based carbon exudation. This late-successional syndrome coincided with stronger extracellular enzyme activity, larger dissolved organic carbon and nitrogen pools, and higher microbial biomass, despite negative net nitrogen mineralization. Species-level analyses showed that biochemical-input traits were jointly shaped by successional stage, species identity, and their interaction. Together, these results show that primary succession did not simply increase or decrease root acquisitiveness. Instead, as soils developed, it changed the nutrient-acquisition pathway that dominated, with direct implications for nutrient cycling and vegetation dynamics in rapidly developing glacier-foreland ecosystems. Full article

Manganese dioxide (MnO₂) modified biochar catalysts derived from biomass and waste polymer feedstocks were synthesized and evaluated as heterogeneous Fenton-like catalysts for solar-driven degradation of Rhodamine B (RhB) in aqueous systems. Biochars produced from maple wood and plastic waste (high-density polyethylene) provided porous carbon matrices with oxygen-rich surface functionalities that enabled effective MnO₂ loading and catalytic activity. Photocatalytic experiments conducted under real sunlight using a solar-collector reactor demonstrated faster RhB degradation compared to a conventional ultraviolet (UV) system, confirming the advantage of solar-driven operation. Complete RhB removal was achieved at initial concentrations of 100–300 ppm, whereas higher dye concentrations (500 ppm) exceeded the catalytic capacity within the tested reaction time. Kinetic analysis revealed catalyst-dependent reaction behaviors, indicating that degradation pathways were strongly influenced by the biopolymer-derived carbon structure and MnO₂ dispersion. Degradation efficiency was correlated with solar irradiance and reactor temperature, with higher UV index conditions enhancing catalytic performance. Reusability tests showed that the catalysts remained active over multiple cycles, although gradual decreases in reaction rates and catalyst recovery were observed. These results demonstrate the potential of biopolymer-derived carbon materials as effective solar-driven catalysts for wastewater treatment applications. Full article

To address the emerging multidrug-resistance crisis caused by Klebsiella pneumoniae, we expressed the endolysin Lys59 derived from phage VB_KpP_HS106 and performed a comprehensive analysis of its antibacterial activity and structural features. Molecular modeling revealed that Lys59 carries a highly positively charged N-terminus and an amphipathic helix at the C-terminus. In vitro antibacterial assays showed that Lys59 exhibited significant bactericidal activity against K. pneumoniae with an approximately 4 log reduction at 50 µg/mL in 2 h. Meanwhile, Lys59 exhibited potent, broad-spectrum activity against both Gram-negative and Gram-positive bacteria. Stability analysis indicated that Lys59 retained high activity over a pH range of 3–9 and a temperature range of 4–55 °C. Notably, the antibacterial activity of Lys59 was found to be regulated by metal ions. Molecular docking indicated that K⁺ can enhance binding stability by interacting with ASN35 and VAL57. In contrast, Mg²⁺ and Ca²⁺ suppressed catalytic function by binding to the essential GLU17 residue. Furthermore, treatment with 200 µg/mL of Lys59 resulted in a 44.6% reduction in K. pneumoniae biofilm biomass. Overall, this study identified a phage-derived endolysin with broad-spectrum antimicrobial activity and demonstrated its potential as an antibacterial agent against multidrug-resistant K. pneumoniae. Full article

Japan’s import market for wood pellets has expanded rapidly since the introduction of the feed-in tariff (FIT) scheme in 2012, with imports exceeding six million tonnes in 2024, positioning Japan as the world’s second-largest wood pellet importer. Despite this expansion, empirical evidence on its demand structure remains limited. This study employs a Dynamic Linear Approximate Almost Ideal Demand System (Dynamic LA-AIDS) model incorporating demand inertia stemming from long-term fuel supply contracts to analyze Japan’s wood pellet import demand from 2012Q1 to 2025Q3. The results reveal a distinct two-tiered structure: North American pellets behave as a strategic necessity, exhibiting price-inelastic demand and a tendency toward a stable long-run procurement pattern following price and expenditure shocks, suggesting procurement practices that prioritize supply security under long-term contracts. In contrast, Vietnamese pellets behave as a price-sensitive commodity, displaying price-elastic demand and relatively sustained responsiveness following such shocks. These results indicate a dual procurement strategy under the FIT scheme that balances stability and cost flexibility. Importantly, the Japanese demand structure differs from the more uniformly price-inelastic patterns observed in the EU and South Korean markets, providing new insights into how institutional frameworks shape biomass allocation and market responsiveness in renewable energy systems. Full article

Four algal adsorbents were prepared from two types of green sea algae (Ulva lactuca and Ulva pertusa), either by treatment with concentrated sulfuric acid or without treatment. A comparative study of Au(III) adsorption in an HCl medium was performed. While both untreated adsorbents showed good performance at low HCl concentrations, the treated adsorbents achieved quantitative adsorption and high selectivity for Au(III) across a broad range of HCl concentrations. The adsorption of Au(III) onto the algal biomass adsorbents followed the typical Langmuir monolayer adsorption model. At an HCl concentration of 0.010 M, the maximum adsorption capacities were 1.14, 0.86, 6.57, and 6.28 mol kg^–1 for DUL, DUP, TUL, and TUP, respectively. A kinetic study conducted at different temperatures was consistent with the pseudo-first-order kinetic model and enabled estimation of the activation energy of the adsorption reaction. Structural changes before and after treatment were analyzed using FT-IR spectroscopy. Confirmation of Au(III) adsorption and its subsequent reduction to the elemental state was achieved through XRD and SEM/EDX analyses as well as digital imaging of the Au-loaded adsorbents. Finally, the adsorbed and reduced Au was successfully desorbed using an acidic thiourea solution. Full article

Sugarcane stores sucrose in a living culm for extended periods, yet the respiratory cost of maintaining this storage tissue remains poorly quantified. We quantified growth and maintenance respiration along the culm (internodes 1 to 12) in three genotypes at mid-season (rapid growth) and end-season (maturation) using a composition-based carbon accounting framework derived from measurements of biomass accumulation and composition. Growth respiration was highest in elongating internodes (3 to 6) and declined with maturation, whereas maintenance respiration increased progressively and dominated in mature storage internodes (10 to 12). Consequently, total sink demand remained substantial even after structural growth slowed, indicating that mature internodes continue to require significant metabolic input despite limited biomass production. To evaluate the potential impact of energetic constraints, we simulated reduced mitochondrial energy contribution to assess the sensitivity of respiratory carbon demand to decreased energetic efficiency. These simulations predicted an increase in glucose requirement for respiration across all internodes, with the largest proportional effect in mature tissue where maintenance costs dominated. Despite this predicted increase in respiratory demand, sucrose accumulation was maintained in mature culms, indicating that respiratory carbon loss remains constrained during storage. This suggests that storage tissue operates with relatively high carbon-use efficiency during maintenance-dominated metabolism. We interpret this pattern as consistent with metabolic configurations that reduce ATP demand, potentially involving partial substitution of ATP-dependent reactions by pyrophosphate (PPi)-dependent pathways, although this mechanism was not directly measured. These findings highlight the importance of maintenance respiration and energetic efficiency in determining sink strength and sucrose yield, and they provide a physiological framework for understanding carbon conservation in long-lived storage organs. Full article

Insect frass fertilisers (IFFs) are increasingly promoted as sustainable soil amendments within circular agricultural systems. However, the compatibility of IFFs with nitrogen-fixing legumes is poorly understood. This study evaluated the effects of a fertiliser produced from Hermetia illucens frass (HexaFrass™; HF) on germination, seedling emergence, shoot growth, and root nodulation in six forage legume species (Trifolium repens L., T. pratense L., T. incarnatum L., T. hybridum L., Melilotus albus Medik., and Medicago lupulina L.). Aqueous HF extracts (1% w/v) had no significant effect on seed germination, whereas higher concentrations (10% w/v) reduced germination in both T. pratense and T. incarnatum. In glasshouse trials, incorporation of HF (3 g per pot) did not affect seedling emergence but significantly increased shoot biomass across all plant species tested, with growth responses comparable to, or exceeding, those obtained with an equivalent mass of organic chicken manure. Across species, the shoot dry weight of the HF-treated plants was over nine times that obtained in the unfertilised control plants. Plant responses to HF application rate were non-linear, with maximum shoot biomass achieved at intermediate doses (~4–5 g per pot). Root nodulation exhibited a similar dose-dependent pattern: low HF application rates slightly enhanced nodulation, whereas higher rates suppressed nodule numbers. These findings indicate that IFFs can promote early growth of forage legumes, but reinforce that for each plant system (plant species, growing conditions, growing medium etc) there is a need to optimise fertiliser application rates to balance nutrient supply while avoiding the inhibitory effects observed at high rates. Further work is needed to establish the compatibility of IFFs with forage legumes in long-term trials performed under field conditions. Full article

Sulfur–soybean oil polymers with tunable thermal insulation properties were synthesized via inverse vulcanization of elemental sulfur and soybean oil and reinforced with biochar (BC) derived from spent barley biomass. Biopolymer films (F-BPs) with sulfur contents ranging from 20 to 80 wt% were prepared, and biochar-filled biocomposites (F-BP-Cs) were obtained using different filler loadings and processing routes. Their structural, morphological, thermal, mechanical, and surface properties were systematically analyzed to establish structure–property relationships, with particular focus on thermal transport behavior. Differential scanning calorimetry (DSC) revealed that sulfur contents ≤50 wt% favored the chemical incorporation of elemental sulfur into the polymer network via covalent bonding, significantly reducing the presence of free crystalline sulfur in the material. SEM images and porosity analysis revealed that BC incorporation and processing conditions significantly affected microstructural connectivity and air-filled porosity. As a result, F-BP-C materials exhibited low thermal conductivities, reaching values of ~0.033–0.039 W/(m·K), comparable to commercial insulating materials such as cork and polymeric foams. This reduction was attributed to increased structural disorder, high interfacial density, and enhanced phonon scattering within the heterogeneous polymer–BC–air system. These findings demonstrate the potential of these biocomposites as sustainable thermal insulating materials derived from industrial and agricultural waste. Full article

Nitrogen use efficiency (NUE) is a major determinant of maize (Zea mays L.) productivity and sustainability, yet the regulatory changes associated with modern breeding remain incompletely understood. Here, we used breeding-era transcriptomic data from 137 elite Chinese maize inbred lines to identify transcriptional regulators associated with maize NUE. Breeding-era expression shifts in NUE effector genes were modest but tissue-specific, pointing to pathway-level transcriptional rewiring during modern breeding. Focusing on the first leaf above the uppermost ear at silking, we identified 69 breeding-era-responsive genes, including 10 transcription factors, and prioritized ZmSPL19 through Pearson correlation analysis with curated NUE-related genes. ZmSPL19 expression declined during modern breeding and showed a nitrate-repressed expression, with lower transcript abundance under nitrogen-sufficient conditions and rapid downregulation upon nitrate resupply. Loss of ZmSPL19 function promoted primary root elongation, biomass accumulation, leaf nitrogen content, soil–plant analysis development (SPAD), photosynthetic rate, kernel number, and grain yield under nitrogen-sufficient conditions. These results identify ZmSPL19 as a breeding-associated negative regulator of growth and yield formation under nitrogen-sufficient conditions and support the value of a breeding-informed strategy for discovering regulators with potential relevance to maize NUE improvement. Full article

The scalable and sustainable production of graphene remains a significant challenge due to the high cost, complex processing, and environmental impact associated with fossil-derived graphite precursors. In this work, we report a biorenewable pathway for producing graphitic carbon from industrial hemp biomass, yielding a plant-derived material called CleanGraphene. This approach provides a renewable and potentially scalable alternative to petroleum- and coal-based graphene production while maintaining competitive structural and electrical performance. CleanGraphene samples are systematically characterized using X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA) to evaluate crystallographic order, layer stacking, defect density, surface chemistry, and thermal stability. The results show that optimized CleanGraphene materials consist of multilayer graphene-like platelets with compact interlayer spacing (d(002) ≈ 3.36–3.37 Å), extended crystallite coherence lengths (L_c up to ~75 nm), large in-plane sp² domains (L_a exceeding ~200 nm), and relatively low defect densities, indicating well-developed graphitic ordering. Electrical conductivity measurements using a binder-free pelletization method and four-point probe analysis demonstrate that the highest quality CleanGraphene samples achieve conductivities of (8.4–8.6) × 10⁴ S m⁻¹, surpassing leading commercial graphene benchmarks measured under identical conditions. Structure–property correlations confirm that electrical performance is governed primarily by crystallite coherence, defect density, and interlayer stacking order, while surface oxygen content plays a secondary role within an ordered graphitic framework. All CleanGraphene samples exhibit excellent thermal stability, retaining more than 95% mass up to ~800–900 °C under an inert atmosphere. Collectively, these findings establish quantitative quality benchmarks for hemp-derived graphene and demonstrate that biomass-based graphene can achieve electrical and thermal performance comparable to, and in some cases exceeding, conventional commercial products. This work highlights industrial hemp as a promising renewable precursor for the scalable production of high-performance graphitic nanomaterials for electrically and thermally conductive composite applications. Full article

Wood is a sustainable material, but hygroscopicity can affect dimensional stability and mechanical durability. Recent research has increasingly focused on combining citric acid with various polyols as eco-friendly crosslinking systems to improve wood properties. Herein, a solvent-free and catalyst-free method was used to synthesize bio-based polyesters from citric acid and mannitol. In situ curing was carried out after vacuum-pressure impregnation of fast-growing poplar wood (Populus deltoides Marshall). Morphological characterization showed that the polyester filled the cell lumen and penetrated the cell wall structure. It was confirmed by Fourier Transform Infrared (FTIR) and cross-polarization/magic angle spinning (CP/MAS) ¹³C nuclear magnetic resonance (NMR) analysis that the polyester formed covalent ester bonds with wood hydroxyl groups, which indicated successful chemical grafting. The dimensional stability and mechanical properties of the modified wood were greatly improved. The parallel compressive strength of the grain reached 41.5 MPa, which was 41.7% higher than that of the untreated wood. This research adopted a citric acid–mannitol polyester, providing a sustainable, economical, and scalable approach for the development of high-performance, degradable wood composites for construction/furniture applications. Full article

Reverse chemical looping pyrolysis (RCLPy) utilizes a reduced oxygen carrier to extract oxygen from the biomass feedstock during the pyrolysis stage and transfer it for the subsequent gasification stage. This decoupled mechanism enables efficient in situ utilization of oxygen and hydrogen inherent in the biomass to produce a hydrogen-rich syngas. In this work, Ca–Fe–Ni composite oxygen carriers for RCLPy were synthesized and their impact on the hydrogen production was investigated and optimized. The results demonstrate that the reduced Ca–Fe–Ni oxygen carrier exhibited both excellent deoxygenation and catalytic cracking capability, significantly promoting the generation of hydrogen and CO. Specifically, the reduced CaFeNi15 oxygen carrier decreases the CO₂ content in the pyrolysis gas from 40.4 vol.% without an oxygen carrier to 6.89 vol.% and with a hydrogen yield of 280.2 mL⸱g⁻¹ biomass and has a total hydrogen production of 318 mL⸱g⁻¹ biomass during the whole pyrolysis–gasification process. These findings underscore the advantages of the RCLPy process in utilizing inherent biomass hydrogen for high-purity syngas production. Future efforts should focus on developing oxygen carriers with enhanced long-term cyclic stability. Full article