Straw Residues Research Articles

Boosting the mechanical performance and fire resistivity of white ordinary portland cement pastes via biogenic mesoporous silica nanoparticles

This study investigates how biogenic mesoporous silica nanoparticles (MS-NPs) extracted from rice straw residues, a sustainable and economical bio-source, affect White Ordinary Portland Cement (WOPC) paste performance. A comprehensive investigation using varied fractions of 0.25, 0.50, 0.75, and 1.0% MS-NPs as an additive to WOPC was conducted to analyze the physicomechanical characteristics of WOPC-MS hardened composites, including compressive strength, fire resistance, and water demand. The beneficial impact of biogenic MS-NPS was verified by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and differential thermo-gravimetric analysis (TGA/DTG) methods, revealing several hydration products such as calcium silicate hydrates (CSHs), calcium ferrosilicate hydrates (CFSHs), and calcium aluminosilicate hydrates (CASHs). These products enhance the overall physical and mechanical properties and the thermal stability of hardened WOPC-MS. The composite comprising WOPC-0.75 MS provides numerous advantages from both an economic and environmental perspective.

Cereal-legume intercropping stimulates straw decomposition and promotes soil organic carbon stability.

Increasing carbon (C) sequestration and stability in agricultural soils is a key strategy to mitigate climate change towards C neutrality. Crop diversification is an initiative to increase C sequestration in fields, but it is unclear how legume-based crop diversification impacts the functional components of soil organic carbon (SOC) in dryland, including the formation and transformation of particulate organic carbon (POC) and mineral-associated organic carbon (MAOC). We investigated the decomposition of straw residues, the fate of photosynthesized C, as well as the formation of MAOC and POC fractions using an in situ13C labeling technique in the soybean-wheat intercropping, soybean-maize intercropping and their respective monocropping systems, with and without cover crops. After 4-year treatments, the total SOC content in bulk soil remained unchanged, while MAOC content increased significantly by 5.6% with intercropping. Moreover, the in situ13C labeling results confirmed that more photosynthesized C was transferred to MAOC, and less was retained in the POC fraction. Intercropping significantly increased total soil N and mineral N content by 15.3% and 13.4%, respectively, and decreased soil and microbial C/N ratio by 11.3% and 17.4%, respectively. This outcome, therefore, relieved microbial N limitation and accelerated straw residue decomposition. Accordingly, the potential of MAOC formation was strengthened for better SOC persistence. Our study suggests that legume-based crop diversification can effectively enrich N and support POC transformation to MAOC, accordingly contributing to the persistent SOC pool and thus potentially achieving C neutrality under climate change in dryland agroecosystems.

Evaluation of the Thermal Insulation Potential of Post-Harvest Blocks Using the Native Strain of the Edible Mushroom Pleurotus ostreatus

In recent years, the need to adopt materials that are partially or fully recyclable or biodegradable has grown significantly. This paper presents a study aiming to develop a physical and thermal characterization of post-harvest blocks (spent mushroom substrate) used in the production of the edible mushroom Pleurotus ostreatus in order to test its feasibility as an insulation material. For this purpose, culture blocks based on wheat straw residues were prepared using a wild strain of the fungus. After the mushroom harvest, the post-harvest blocks were evaluated for stability, thermal conductivity, moisture content, fire behavior, and surface analysis. The results showed that the post-harvest blocks had an average thermal conductivity of 0.032 W/mK, a density of 56.63 kg/m3, and a moisture content of 5.96%. They also exhibited high fire resistance. The culture blocks showed stable dimensional properties, reasonable productivity, low moisture, high density, and fire resistance. Therefore, results suggest that this material could be used as insulation in construction.

Retraction notice to "Effects of burning rice straw residue on-field on soil organic carbon pools: Environment-friendly approach from a conventional rice paddy in central Viet Nam"[Chemosphere 294 (2022) 133596

Retraction notice to "Effects of burning rice straw residue on-field on soil organic carbon pools: Environment-friendly approach from a conventional rice paddy in central Viet Nam"[Chemosphere 294 (2022) 133596

Effect of environmental factors on seed germination and seedling emergence of weedy rice (Oryza sativa f. spontanea) in China

Abstract Weedy rice (Oryza sativa f. spontanea Auct. ex Backer) is a troublesome annual weed from the Gramineae family and infests rice (Oryza sativa L.) fields globally, with a notable presence in China. However, limited information is available regarding the effects of diverse environmental factors on its germination and emergence. A better understanding of the seed biology and ecology of weedy rice is crucial for developing effective weed management strategies. Experiments were conducted to evaluate the effects of temperature, light, soil burial depth, wheat (Triticum aestivum L.) crop residue amount, salt stress, osmotic stress, and radiant heat on the germination and seedling emergence of weedy rice. Weedy rice exhibited robust germination (>98%) when exposed to varying day/night temperatures (20/15 to 35/30 C) and remained unaffected by light conditions. Seedling emergence was not influenced within the top 5-cm soil layer, where 100% of the seedlings emerged. However, emergence decreased as the soil burial depth increased, eventually resulting in no emergence from a burial depth of 11 cm. The soil burial depth required for 50% of the maximum emergence was 8.3 cm. Seedling emergence ranged from 97% to 100% across different amounts of the wheat straw residue cover (0 to 10,000 kg ha−1). The sodium chloride concentration and osmotic potential required for 50% were 230.8 mM and −0.5 MPa, respectively. No germination was observed when weedy rice seeds were exposed to >110 C pretreatment (radiant heat for 5 min), indicating that residue burning could reduce infestation of weedy rice. The insights gained from this study contribute valuable knowledge to enhance the integrated management of weedy rice in China.

Biochar derived from straw residue prepared via combined pre-treatment designed for efficient removal of tetracycline hydrochloride and sulfadiazine sodium salt

In this study, straw residue (SR) was prepared from corn straw by a combined pre-treatment method that involved both microbial treatment (Myrothecium verrucaria, Aspergillus niger, and Trichoderma reesei) and treatment with ρ-toluenesulfonic acid. After pre-treatment, the cellulose content of the residues reached 79.3 %, 72.1 %, 83.5 %, and 85.2 %, respectively. The results indicated that Aspergillus niger and Trichoderma reesei effectively destroyed the corn stover structure, improving the efficiency of the subsequent treatment. Following carbonation and activation processes, the SRs were converted into a series of biochars (ACCC, ACMC, ACTC, and ACNC) with large specific surface areas (2343, 2219, 2693, 2672 m2 g−1). The prepared biochars demonstrated excellent performance in adsorption tests performed using tetracycline hydrochloride (TC) and sulfadiazine sodium salt (SDZ) as adsorption models. The maximum adsorption capacities recorded for TC (908, 1117, 1216, and 1189 mg/g) and SDZ (930, 965, 1033, and 1083 mg/g) were higher than most of the other adsorbents. Furthermore, the potential adsorption mechanisms included pore filling, π-π interactions, hydrogen bonding, and electrostatic attraction. Even after 5 test cycles, the biochar retained over 75 % of its adsorption performance, highlighting its strong potential for applications in removing antibiotics from water.

Production and characterization of pulp and paper from flax straw

Flax (Linum usitatissimum) is a bast fiber plant known for its long fibers, making it an excellent source of pulp for paper production. In Ethiopia, flax is primarily cultivated for oil, with the residual straw utilized for papermaking. This study focuses on pulping flax straw using the Kraft process and investigates its chemical composition, proximate analysis, and morphological properties. The proximate analysis revealed an ash content of 4.13% and moisture content of 11%. Chemical composition analysis showed cellulose at 51.34%, hemicellulose at 25.20%, lignin at 14.12%, ash at 4.13%, and extractives at 5.21%. The morphological properties included a fiber length of 1.41 mm, diameter of 16.78 μm, lumen width of 9.45 μm, and cell wall thickness of 3.77 μm. Flax straw exhibited an acceptable Runkel ratio (0.8) and flexibility coefficient (56.32), placing it within the range of non-wood fibers. SEM analysis of the pulp’s morphology was conducted to assess fiber structure, including the presence of cracks. Pulp quality and length are directly linked to paper strength. Various pulping conditions were studied using a full-factorial design, with optimum conditions being 10% alkaline, 131.74°C, and 120 min of cooking time, yielding a pulp with a Kappa number of 10.45 and a yield of 40.56%. The resulting paper demonstrated standard tensile, tearing, and burst strengths, indicating that flax straw is a promising raw material for paper production.

Investigating interface adhesion of PLA-coated cellulose paper straws: Degradation, plant growth effects, and life cycle assessment

Although bioplastics and paper straws have been introduced as alternatives to single-use plastic straws, their potential environmental, economic, and social impacts have not been analyzed. This study addresses this gap by designing a polylactic acid layer interface adhesion on cellulose paper-based (PLA-P) composite straws by a dip molding process. This process is simple, efficient, and scalable for massive production. Optimizing key manufacturing parameters, including ice bath ultrasonic, overlapping paper strips (2 strips), winding angle (60°), soaking time (5 min), and drying temperature (50 °C), were systematically evaluated to improve straw quality and manufacturing efficiency. PLA chains were found to deposit onto the cellulose network through intermolecular interactions to form a consistent "sandwich" structure, which can improve adhesion, water resistance, and mechanical properties. Interestingly, PLA-P straws effectively decomposed in soil and compost environments, with a 35–40 % degradation rate within 4 months. Besides, PLA-P straw residues affected seed germination and plant growth, but no significant toxic effects were detected. Further, microplastics were observed in soil and plant tissues (roots, stems, and leaves), and their possible diffusion mechanisms were explored. The results of a comprehensive life cycle assessment (LCA) and cost analysis showed that the process improvements reduced the ecological footprint of PLA-P straws and showed good prospects for commercial application. The study's findings contribute to the understanding of bioplastics and paper straws in effectively reducing environmental impact and fostering sustainable development.

Enhanced carbon use efficiency and warming resistance of soil microorganisms under organic amendment

The frequency and intensity of extreme weather events, including rapid temperature fluctuations, are increasing because of climate change. Long-term fertilization practices have been observed to alter microbial physiology and community structure, thereby affecting soil carbon sequestration. However, the effects of warming on the carbon sequestration potential of soil microbes adapted to long-term fertilization remain poorly understood. In this study, we utilized 18O isotope labeling to assess microbial carbon use efficiency (CUE) and employed stable isotope probing (SIP) with 18O-H2O to identify growing taxa in response to temperature changes (5–35 °C). Organic amendment with manure or straw residue significantly increased microbial CUE by 86–181 % compared to unfertilized soils. The microorganisms inhabiting organic amended soils displayed greater resistance of microbial CUE to high temperatures (25–35 °C) compared to those inhabiting soils fertilized only with minerals. Microbial growth patterns determined by the classification of taxa into incorporators or non-incorporators based on 18O incorporation into DNA exhibited limited phylogenetic conservation in response to temperature changes. Microbial clusters were identified by grouping taxa with similar growth patterns across different temperatures. Organic amendments enriched microbial clusters associated with increased CUE, whereas clusters in unfertilized or mineral-only fertilized soils were linked to decreased CUE. Specifically, shifts in the composition of growing bacteria were correlated with enhanced microbial CUE, whereas modifications in the composition of growing fungi were associated with diminished CUE. Notably, the responses of microbial CUE to temperature fluctuations were primarily driven by changes in the bacterial composition. Overall, our findings demonstrate that organic amendments enhance soil microbial CUE and promote the enrichment of specific microbial clusters that are better equipped to cope with temperature changes. This study establishes a theoretical foundation for manipulating soil microbes to enhance carbon sequestration under global climate scenarios.

Half substitution of mineral N with fish protein hydrolysate enhancing microbial residue C and N storage and climate benefits under high straw residue return

The widespread utilization of straw return was a popular practice straw disposal for highly intensive agriculture in China, which has brought about some negative impacts such as less time for straw complete biodegradation, aggravation of greenhouse gas evolution, and lower efficient of carbon accumulation. It was urgent to find an eco-friendly N-rich organic fertilizer instead of mineral N as activator to solve the above problems and lead a carbon accumulation in long tern management. Besides, microbial necromass was considered as a crucial contributor to persistent soil carbon (C) and nitrogen (N) pool. How organic fertilizer activators influence microbial residue under different amount of crop residues input remained unclear. Thus, soils incorporating moderate and high rate of rice straw residue with additions of half and full of organic activators (fish protein hydrolysates vs. manure) were incubated for measuring carbon dioxide (CO2) and nitrous oxide (N2O) emission, microbial community and necromass. It was found that soil CO2 emission was rapidest during the first 13 days of straw decomposition but remained lowest in the treatments of 50% mineral N substituted by fish protein hydrolysate. There were that 81%–89% of total CO2 release and 59%–65% of total N2O emission occurred within 60 days of incubation period, and bacterial community and nitrate positively affected soil CO2 and N2O release respectively. Straw incorporation amount and organic activator application interactively influenced soil CO2 emission but not affected soil N2O emission. After 360 days of incubation, the difference of bacterial necromass was noticeable but fungal necromass remained almost unaltered across all treatments. All treatments showed generally comparable contribution of microbial necromass N to the total N pool. The treatment of 50% mineral N substituted by fish protein hydrolysate under high rate of straw input (HSF50) promoted the highest proportion of microbial necromass C in soil organic C because of alleviating N limitation for microorganisms. Finally, HSF50 was recommended as an eco-friendly strategy for enhancing microbial necromass C and N storage and climate benefits in agroecosystems.

Shift of microbial taxa and metabolisms relying on carbon sources of rhizodeposits and straw of Zea mays L

Decoding the fundamental taxa that decompose crop rhizodeposits (rhizo-C) and/or straw residue (straw-C) is crucial for understanding the role of plant-derived carbon (C) in driving microbial community assembly and consequent C decomposition. Here, a parallel 13C-labeling design, DNA-SIP, and metagenomics techniques were combined to separate maize rhizo-C utilizers from straw-C utilizers in agriculture soils containing both C sources. Also, by comparing bacterial utilizers and their C metabolisms in soils amended with a single C source (e.g., straw-13C only) and two C sources (e.g., straw-13C and rhizo-12C), we investigated the shift of composition and metabolisms of soil bacterial utilizers responding to C sources shift (e.g., compositional and metabolic changes of straw-13C utilizers from soil containing straw-13C to soil containing both straw-13C and rhizo-12C). We revealed i) Proteobacteria predominantly utilized rhizo-13C, while Firmicutes dominated the community specializing in straw-13C decomposition in soil containing both straw-C and rhizo-C; ii) the planted maize (i.e. rhizo-C input) changed community composition and metabolisms of straw-C utilizers, which shifted from K-strategists characterized by an enrichment of lignin-degrading genes to r-strategists which exhibited an enrichment of genes related to polysaccharide degradation. This metabolic shift of straw-C utilizer ultimately reduced straw-13C mineralization by 25.6% when maize was planted. This study identified the distinct utilizers of rhizo-C and straw-C in soils containing both C sources, and shed light on the shift of bacterial community and their metabolic activities responding to the changes of maize-derived C sources.

Carbon budget of paddy ecosystems in China simulated by denitrification‐decomposition model

AbstractQuantifying the carbon budget in rice paddy ecosystems is fundamental to understanding the role of paddy fields as carbon sinks or sources and to mitigating global climate change. This study used a process‐based model of the denitrification‐decomposition (DNDC) model to estimate greenhouse gas (GHG) emissions and carbon sinks in the paddy ecosystem across China. The simulation results showed that the GHG emissions were 0.147 Pg C‐equivalent year−1 and that the carbon sequestration in rice plants and soils reached 0.253 Pg C year−1 in 2016, indicating high carbon sequestration potential of the Chinese paddy ecosystem. Land management had a great influence on carbon budgets, among which straw residue incorporation rate and nitrogen fertilizer applications had a stronger influence on carbon budgets, particularly for double cropping rice. These results indicate that appropriate tillage practices can reduce GHG emissions and increase carbon sequestration of rice ecosystems while ensuring rice yields.

Relay-cropping enhances the availability of low iLUC risk lignocellulosic feedstock for advanced biofuels

The relay-cropping (R) of a winter cereal and a high biomass yielding legume for advanced biofuel production can enlarge the legume growing season, thus increase its biomass yield and synchronize nitrogen (N2)-fixation capacity to uptake. The aim of the present study was to evaluate the biomass and food yield of two sunn hemp (Crotalaria juncea L.; cv. Ecofix) – wheat (Triticum aestivum L.; cv. Bologna) relay-cropping systems compared to double-cropping, in order to explore the impact on grain and biomass yield of the variable crops overlapping periods. The evaluated relay-cropping systems foreseen an early November wheat sowing into no till bare soil with: i) sunn hemp harvested at full flowering (beginning of November, R1) and ii) sunn hemp harvested at the end of flowering (end of November, R2). In the control (C) double-cropping, sunn hemp was harvested at the beginning of flowering (end of September). Quantitative and qualitative parameters were evaluated for each system across two growing seasons (2019–20 and 2021–22). Sunn hemp biomass and wheat straw residues were determined. The grain qualitative parameters determined for wheat were: grain volume weight (VW), crude protein, wet gluten, starch and Zeleny index (ZI). The R1 and R2 sunn hemp-wheat relay-cropping biomass yield (12.5 Mg d.m. ha−1 y−1) was similar to C (11.3 Mg d.m. ha−1 y−1). In 2019–20, environmental conditions were more favorable, thus, yields were higher than in 2021–22 by 72 %. Wheat grain yields in 2021–22 were higher in R1 (2.9 Mg d.m. ha−1) than C (2.0 Mg d.m. ha−1), with R2 showing intermediate values. In 2019–20, however, the grain quality was higher in R1 than in C for crude protein (+11 %), wet gluten (+15 %), and ZI (+26 %) eventually due to an increased N2-fixation by sunn hemp that reached full flowering. The local availability of low iLUC risk lignocellulosic feedstock for advanced biofuel could be increased through crop intensification with relay-cropping, showing the potential to provide additional biomass and enhance food quality thus complying with the additionality measures set out by the Delegated Regulation of REDIII.

Dry season residual straw reduces nitrous oxide emissions during rice season in upland-paddy rotation systems by inhibiting soil denitrification

Dry season residual straw reduces nitrous oxide emissions during rice season in upland-paddy rotation systems by inhibiting soil denitrification

Removal of lead ions from aqueous solution by modified nanocellulose.

Heavy metals significantly impact the environment due to their non-biodegradable, toxic, and carcinogenic behaviors. Lead contaminants impose severe health impacts on humans and the water environment. Therefore, eco-friendly and efficient lead ion removal practices such as nanotechnology are an urgent requirement for the abatement of lead pollution. In the present study, nanocellulose was synthesized from the cotton straw residue using chemical methods and modified with titanium dioxide to form a nanocomposite. The nanocomposite synthesized was characterized by using FTIR, XRD, FESEM, and BET. FTIR results noticed peaks at 1648.43 and 1443.57cm-1 for cellulose and Ti-O-Ti bonding at 505.02cm-1. The nanocomposite was noticed to be disordered and irregular in shape. The nanocomposite has particle sizes of 83nm. The nanocomposite crystalline particle had 65% anatase and 32% rutile phases observed from the XRD result. BET results show that the surface area of nanocellulose increases after surface modification from 25.692 to 42.510 m2/g. The adsorption capacity of the nanocomposite was 0.552mg/g was noticed. The Elovich kinetic and Baudu isotherms are the best-fitted models for lead ion adsorption. Thermodynamic parameters resulted in Gibbs free energy decreasing with temperature. This study revealed that modified cellulosic adsorbents efficiently absorbed lead ions derived from cotton straws.

Investigating the Effects of Banana-Derived Biochar and Straw Residues on Growth and Yield of Maize (Zea Mays L.) Crop

Biochar application with straw residues can enhance their rate and increase the availability of nutrients for maize crop under field conditions. Therefore, this present study was primarily aimed at exploring the combined effect of banana derived biochar and straw residues application on the biomass production and the yield components of maize crop. The experimental study was consisting of six treatments: T-1 control, T-2 Biochar (40 ha-1), T-3 12.5 tons ha-1 straw residues, T-4 25 tons ha-1 straw residues, T-5 40 tons ha-1 biochar + 25 tons ha-1 straw residues, T-6 40 tons ha-1 biochar + 12.5 tons ha-1 straw residues. Results displayed that combine application of Biochar (40 tons ha-1) and straw residues (25 tons ha-1) enhanced the shoot fresh biomass (208%), Root fresh biomass (85%), Root length (85%), Number of grains per cob (262%), Seed index (68%), cob length (79%), grain yield (120%) and leaf area (80 %) as compared to control. While, 40 tons ha-1 biochar + 12.5 tons ha-1 straw residues increased shoot fresh biomass (197%), root fresh biomass (57%), root length (41%), number of grains per cob (220%), seed index (37%), cob length (69%), grains yield (103%) and leaf area (64%) in comparison to control. Most of the growth parameters were positively correlated with yield components. Similarly, correlation coefficient indicated significant association among different morphological characteristics when subjected to these combined applications of biochar and straw residues. Hence, this study concluded that combine application of banana biochar and straw residues promoted the grain growth and yield of the maize crop under field condition.

Estimation of greenhouse gas emission due to open burning of rice straw using Sentinel data

In recent decades, Vietnam has gradually become a critical global rice producer. During that production process, residual straw becomes an environmental pollutant due to open burning, raising greenhouse gas emissions. This study combines the optical images of the Sentinel-2 satellite and the radar images of the Sentinel-1 satellite to estimate the dry biomass of rice and to determine gas emissions due to rice straw burning over the fields in Quoc Oai district, Hanoi city for urban environmental management purposes. Sentinel-2 images have been classified into the land covers, thereby identifying the areas of ​​rice cultivation and the areas of ​​burned straw. Meanwhile, the Sentinel-1 radar image has been used to calculate the dry biomass of rice due to its ability to penetrate clouds, an obstacle to optical images in tropical regions. Furthermore, a field trip during harvesting season allows us to measure aboveground dry biomass. Then, the analysis shows a high correlation between the backscatter V.V. and V.H. of the radar image and the in-situ dry biomass (R=0.923 and R2=0.852), with a relatively low average error (RMSE = 6.58 kg/100 m2). By linear regression method, the study found the total rice dry biomass of 28728.5 tons, which was obtained after the Summer rice crop 2020 for the whole Quoc Oai district, of which 2037.91 tons of rice straw have been burned, releasing a large amount of greenhouse gas emission with 2398.6 tons of CO2, 189.5 tons of CO, 18.8673 tons of PM10 dust, 17.2087 tons of PM2.5 dust and some other gases. The identical procedure has also been applied to the western region of Hanoi city center to estimate the amount of gas emissions. This study has proven the effectiveness of an approach and contributed to supporting urban managers in proposing appropriate policies to monitor and protect the environment.

Simultaneous removal of U(VI) and tetracycline from aqueous solution by biochar-supported nano-hydroxyapatite: New insights into the role of biochar and interactions between pollutants

U(VI) and tetracycline (TC) in hospital wastewater pose serious threats to human health and the environment. In this study, agricultural corn straw residue was utilized as a precursor for biochar, and biochar-supported nano-hydroxyapatite (nHAP) adsorbents (CSPCs) were synthesized at various ratios. These CSPCs were employed for the removal of U(VI) and TC in both one-component and two-component systems. In the one-component system, the adsorption capacity of the material was related to the ratio of nHAP to biomass, and the maximum adsorption capacities of CSPC-1 (nHAP/biomass = 1/1) for U(VI) and TC were 724.63 mg g−1 and 15.06 mg g−1, respectively. The XPS and XRD results confirmed that biochar promoted the dissolution and precipitation of U(VI) by nHAP, which stabilized the adsorption of U(VI) by CSPC-1. In the two-component system, the complexation strength of U(VI) and TC had a significant effect on the adsorption of both. At pH < 3.0, U(VI) inhibited the adsorption of TC, whereas TC enhanced the adsorption of U(VI). However, at pH > 4.0, the adsorption of U(VI) and TC were mutually reinforcing. At pH = 5.0, TC inhibited the adsorption of U(VI) only when the concentration of TC was significantly greater than that of U(VI). Combined with the systematic analysis of the FTIR, XPS and Raman spectroscopic results, these results suggest that these phenomena can be attributed to the complexation-bridging interactions between U(VI) and TC and their competition for adsorption sites.

The Application of Rice Straw with Reduced N Fertilizer Improves the Rice Yield While Decreasing Environmental N Losses in Southern China

To investigate the effects of straw residues with reduced nitrogen (N) fertilizer on greenhouse gas (GHG) and N losses in paddy fields, we conducted a field experiment during two growing seasons in paddy rice systems in southern China to evaluate the impacts of the application of straw residues with reduced N fertilizer on rice yield, GHG emissions, and ammonia (NH3) volatilization. The four treatments included N100 (conventional dose of N fertilizer), SN100 (conventional dose of N fertilizer + straw), N60 (60% of the conventional dose of N fertilizer), and SN60 (60% of the conventional dose of N fertilizer + straw). We found that the yield of the SN60 treatment was slightly reduced, but the partial factor productivity of applied N (PFPN) was significantly increased by 63.9% compared to the N100 treatment. At the same N application rate, the application of straw increased soil organic C (SOC), methane (CH4) emissions, carbon dioxide (CO2) emissions, global warming potential (GWP), greenhouse gas intensity (GHGI), and net ecosystem carbon budget (NECB), but significantly decreased soil N2O emissions and NH3 volatilization. Compared with conventional fertilization (N100), straw residues with reduced N fertilization (SN60) reduced N2O emissions and NH3 volatilization by 42.1% and 23.9%, and increased GHGI and NECB by 11.1% and 18.3%, respectively. The results indicate that straw residues with reduced N fertilizer are a feasible strategy to reduce N losses in paddy fields while increasing carbon sequestration.

Performance Analysis of Waste Biomass Gasification and Renewable Hydrogen Production by Neural Network Algorithm

Abstract This study assesses renewable hydrogen production via gasification of residual biomass, using artificial neural networks (ANNs) for predictive modeling. The process uses residues from sugarcane and orange harvests, sewage sludge, corn byproducts, coffee remnants, eucalyptus remains, and urban waste. Simulation data from aspen plus® software predict hydrogen conversion from each biomass type, with a three-layer feedforward neural network algorithm used for model construction. The model showed high accuracy, with R2 values exceeding 0.9941 and 0.9931 in training and testing datasets, respectively. Performance metrics revealed a maximum higher heating value (HHV) of 18.1 MJ/kg for sewage sludge, the highest cold gas efficiency for urban and orange waste (82.2% and 80.6%), and the highest carbon conversion efficiency for sugarcane bagasse and orange residue (92.8% and 91.2%). Corn waste and sewage sludge yielded the highest hydrogen mole fractions (0.55 and 0.52). The system can reach relative exergy efficiencies from 24.4% for sugarcane straw residues to 42.6% for sugarcane bagasse. Rational exergy efficiencies reached from 23.7% (coffee waste) to 39.0% (sugarcane bagasse). This research highlights the potential of ANNs in forecasting hydrogen conversion and assessing the performance of gasification-based renewable hydrogen procedures using biomass wastes.