Search Results (260)

Agri-food processing in Europe generates large quantities of organic residues that remain insufficiently valorized despite their significant biochemical potential. Among these, wastes derived from root vegetables and anthocyanin-rich crops represent a distinct category of non-lignocellulosic biomass characterized by high moisture content, low lignin levels, and substantial concentrations of fermentable carbohydrates and bioactive compounds. This review provides a systematic overview of the origin, composition, and valorization potential of these residues, as well as extraction methods, with particular emphasis on root vegetable processing wastes and pigment-rich agri-food by-products. Valorization options are discussed within an integrated biorefinery perspective, particularly for specific compositional characteristics of the investigated waste streams related to suitable recovery strategies, followed by the conversion of post-extraction residues into secondary products and bioenergy. These options are evaluated in relation to the origin, biochemical profile, and valorization potential of each waste stream, as detailed in the dedicated sections of the review. Cascading utilization strategies are highlighted as a means to improve resource efficiency and reduce environmental burdens compared to single-route treatment options. By integrating information on feedstock characteristics and processing pathways, this review contributes to a better understanding of non-lignocellulosic agri-food wastes and supports the development of sustainable valorization strategies in the European circular bioeconomy. Full article

Large-scale agricultural remote sensing monitoring is challenged by pronounced spatial heterogeneity arising from fragmented terrain, complex climatic backgrounds, and diverse cropping structures. However, existing agricultural zoning schemes generally lack an integrated consideration of remote sensing imaging mechanisms and key variable conditions such as atmospheric interference and crop phenology, limiting their direct utility in guiding region-specific sensor selection and classification algorithm calibration. To address this limitation, this study integrates multi-source earth observation data and agricultural statistical information to construct an Agricultural Remote-sensing Classification Difficulty Index (ARCDI) from multiple dimensions, including image availability, cropping structure, cropland fragmentation, and topographic environment. On this basis, a graph theory-based spatially constrained Skater clustering algorithm is introduced to establish a two-tier “cropland–major cereal crops” zoning framework oriented toward remote sensing applications. The results indicate that the proposed framework delineates five distinct first-tier cropland classification difficulty zones across China. This zoning scheme effectively quantifies the regional heterogeneities in monitoring challenges. Building upon this first-tier zoning, the framework is further refined into 50 second-tier major cereal crop classification difficulty zones, including 13 winter wheat zones, 21 maize zones, and 16 rice zones. Statistical tests and spatial analyses demonstrate that the proposed zoning scheme significantly outperforms conventional clustering approaches in balancing within-zone homogeneity and spatial continuity. This advantage is quantitatively reflected by consistently lower residual spatial autocorrelation (residual Moran’s I ≈ 0.10–0.11) and an approximately 20% reduction in within-zone variance compared with other spatially constrained methods. Extensive field-sample validation provides preliminary evidence of an inverse relationship between crop-type classification difficulty and accuracy. These results confirm the framework’s reliability in identifying regional difficulty and its decision-support value for selecting remote sensing strategies. Overall, this study systematically elucidates the spatial differentiation patterns of remote sensing classification difficulty for cropland and major cereal crops across China. The proposed framework provides robust scientific support for data selection, algorithm optimization, and differentiated strategy formulation in national-scale agricultural monitoring, thereby facilitating the operationalization of regional agricultural remote sensing applications. Full article

Small-scale biogas plants in developing countries present a viable alternative to traditional polluting energy sources, particularly in rural and underserved communities. These systems typically rely on locally sourced livestock manure; however, inconsistent supply often results in underfeeding, reduced biogas production, and, in many cases, system abandonment. Co-digestion with crop residues presents a promising strategy to enhance feedstock availability and system resilience. However, the recalcitrant nature of lignocellulosic biomass and limited access to suitable pretreatment technologies have constrained its adoption. This paper evaluates feasible pretreatment methods for integrating crop residues, especially straw, into small-scale biogas systems. Using the Analytic Hierarchy Process (AHP), pretreatment methods are assessed based on five criteria: (i) technology simplicity, (ii) energy requirements, (iii) capital and operational costs, (iv) effectiveness, and (v) environmental impact. The analysis identifies microbial pretreatment using the liquid fraction of digestate, combined with mechanical size reduction, as the most suitable approach for small-scale implementation, utilizing low-cost, simplified mechanical devices adaptable to various crop residues with minimal energy input. A conceptual design of a demonstration plant is proposed to validate this integrated pretreatment approach and assess its impact on biogas yield, system performance, and technology adoption. The design incorporates an on-site digestate separation unit to supply microbial inoculum and emphasizes simplicity and cost-effectiveness in material handling and energy use. Pilot trials are proposed to evaluate key performance indicators, including specific methane yield (LCH₄/gVS added), volatile solids reduction (%), and methane content increase (%), ensuring evidence-based adoption and practical applicability of the design. Full article

Freshwater scarcity limits agricultural production in southern Xinjiang, China, while saline groundwater utilized for direct irrigation adversely affects soils and crops. Excessive nitrogen fertilizer is often applied to compensate for these adverse effects, potentially jeopardizing soil environmental quality. A two-year field experiment was conducted to assess the impact of decreased nitrogen application on cotton growth, nitrogen use efficiency, and yield under different irrigation water salinity levels, with the addition of biofertilizer. The experiment was undertaken on drip-irrigated cotton fields in southern Xinjiang, China, during 2021 and 2022. Three salinity concentrations of irrigation water were quantified: W₁ (1 g L⁻¹), W₂ (3 g L⁻¹), and W₃ (7 g L⁻¹). Under all three salinity levels, conventional fertilization (F1) served as the control, and F0, a no-nitrogen treatment, was also utilized. A total of 18 treatments were assessed using four nitrogen fertilizer application rates in conjunction with biofertilizer: no nitrogen (B₀), 100% conventional nitrogen rate (B₁), 85% conventional nitrogen rate (B₂), and 70% conventional nitrogen rate (B₃). The findings showed that adding biofertilizer considerably increased cotton output under both freshwater and brackish water irrigation regimes when compared to traditional nitrogen fertilization. In just two years, the yield of seed cotton grew by 6.15–10.56% (W₁) and 6.49–11.81% (W₂). In 2021, lint yield climbed by 11.79% (W₁), and in two years, it increased by 6.69–15.51% (W₂). Although internal nitrogen use efficiency (iNUE) initially rose and subsequently fell with escalating nitrogen rates, the application of lower nitrogen combined with biofertilizer significantly enhanced agronomic nitrogen use efficiency (aNUE) and diminished soil nitrogen residue. Recommended nitrogen application rates for cotton, utilizing 1200 kg ha⁻¹ of biofertilizer, were established for diverse irrigation water qualities to achieve optimal nitrogen reduction, maximum iNUE, and peak yield: 283.21–322.95 kg ha⁻¹ under freshwater irrigation (W₁), 281.00–328.14 kg ha⁻¹ under brackish water (W₂) irrigation, and ≥326.28 kg ha⁻¹ under saline irrigation (W₃). These findings recommend the optimization of fertilizers across various irrigation conditions and facilitate the efficient utilization of saline water resources. Full article

Water scarcity, poor soil, and low water and fertilizer utilization are major challenges on agricultural production in the tableland region of China’s Loess Plateau. Optimizing tillage patterns and improving soil nutrient status can improve crop yield and water and fertilizer utilization efficiency. A field trial was initiated in 2005 to assess the impacts of various tillage and fertilization practices on dryland agricultural production. A split-plot design was used, with tillage practices (traditional tillage and no tillage) as the main plot treatment and fertilization management (no fertilization (CK), mineral nitrogen (N), mineral phosphorus (P), composted cow manure (M), a combination of mineral nitrogen and phosphorus (NP), and a combination of mineral nitrogen, phosphorus, and composted cow manure (NMP)) as the split-plot treatment. An experiment was conducted from 2022 to 2024. The NMP treatment resulted in lower bulk density, a lower three-soil-phase index, and higher mean weight diameter, geometric mean diameter, soil water storage, total nitrogen, and soil organic matter than the CK. In the no-tillage treatment, the crop roots were less effective at extracting water from the deep subsoil, leading to greater residual moisture at depth (especially in the 120–200 cm soil layer) and lower yield and water use efficiency than in traditional tillage. The grain yield and water use efficiency were 9.2% and 8.4% lower, respectively, under no tillage than under traditional tillage. The NMP under traditional tillage exhibited lower surface soil bulk density and a higher three-soil-phase index, mean weight diameter, geometric mean diameter, soil organic matter, total nitrogen, and water use efficiency than the unfertilized control, resulting in higher grain yields. The NMP under traditional tillage is recommended to increase grain yield and water use efficiency in wheat–maize rotation systems in the tableland region of China’s Loess Plateau. Future studies should analyze the deep root architecture and the effect of weed competition on soil water depletion. Full article

Agricultural practices (APs) comprehensively regulate crop growth; however, comprehensive studies evaluating the effects of APs on crop yield, water use efficiency (WUE), and nitrogen use efficiency (NUE) remain scarce, particularly regarding determining optimal APs for winter wheat in wheat–maize rotation systems. Here, this study conducted a meta-analysis based on 305 studies globally (4009 pairs of observations), focusing on five APs: irrigation, fertilization, tillage, residue utilization, and mulching. And the results indicated that APs significantly increased winter wheat yield (31.1%), NUE (14.7%), and WUE (27.6%), with fertilization showing the most pronounced effects at 43.7%, 16.9%, and 44.7%, respectively. Specifically, compared to no fertilization, combined organic and mineral fertilizer produced the highest yield increase (141.5%); among conventional fertilization, biochar addition showed the best yield increase (19.1%). Slow-controlled/-release fertilizer and inhibitor addition increased NUE by 17.7% and 26.6%, respectively, and residue utilization and mulching improved WUE (by 17.3% and 33.2%). Moreover, in cold and arid regions (mean annual temperature [MAT] < 13 °C and total annual precipitation [TAP] < 550 mm), APs showed stronger promotion of wheat yield and WUE, while in warm and humid regions, the increase in NUE was more significant (15.3–16.1%). When experiment duration was ≥5 years, APs resulted in the highest yield increase (47.9%), while NUE and WUE increased in short-term experiments. Although APs with high nitrogen application rates resulted in a greater yield increase (51.5%), fertilization significantly reduced NUE above 198 kg N ha⁻¹. Structural equation modeling revealed that, among APs, climatic conditions, soil properties, and management factors, APs were the primary driver of changes in yield and WUE, while NUE was mainly regulated by management factors. Overall, these findings provided an empirical basis for optimizing agricultural practices in wheat–maize systems and offer guidance for developing site-specific policy design. Full article

Pathogenic bacteria utilize a type III secretion system (T3SS) to inject type III effectors (T3Es) into plant cells, suppressing plant immunity and facilitating colonization. Paracidovorax citrulli, the causal agent of bacterial fruit blotch (BFB) of Cucurbitaceae crops, harbors a functional T3SS like many other plant pathogens. The expression of its T3SS and T3Es is regulated by the two-component system response regulators HrpG and HrpX. Here, we demonstrate that the aspartic acid (Asp) residues at positions 52 and 60 in P. citrulli HrpG are essential for its complete function. Plasmid-mediated complementation of the ΔhrpG mutant with hrpG carrying Asp52→alanine (Ala) or Asp60→Ala mutations failed to restore the ability of P. citrulli to induce a hypersensitive response (HR) in tobacco, whereas the Asp46→Ala mutation fully rescued this phenotype. Furthermore, genomic hrpG point mutations generating strains Aac5 (D52A) and Aac5 (D60A) abolish the activation of hrpX transcription, resulting in decreased HrpX accumulation. Collectively, Asp 52 and Asp 60 in P. citrulli HrpG are essential for transcriptional activation activity of hrpX and HR induction, serving as a potential phosphorylation site (Asp 52) for upstream histidine kinases and a Mg²⁺ coordination site (Asp 60). Given that conserved Asp residues often function as phosphorylation sites in two-component system response regulators, this study provides a foundation for identifying upstream histidine kinases that modulate HrpG activity in P. citrulli. Full article

Agricultural biomass has potential as a renewable and versatile carbon feedstock for developing eco-friendly and biodegradable polymers capable of replacing conventional petrochemical plastics. To address the growing environmental concerns associated with plastic waste and carbon emissions, lignocellulosic residues, edible crop by-products, and algal biomass were utilized as sustainable raw materials. These biomasses provided carbohydrate-, lipid-, and lignin-rich fractions that were deconstructed through optimised physical, chemical, and enzymatic pretreatments to yield fermentable intermediates, such as reducing sugars, organic acids, and fatty acids. The intermediates were subsequently converted through tailored microbial fermentation processes into biopolymer precursors, primarily polyhydroxyalkanoates (PHAs) and lactate-based monomers. The resulting monomers underwent polymerization via polycondensation and ring-opening reactions to produce high-performance biodegradable plastics with tunable structural and mechanical properties. Additionally, the direct extraction and modification of naturally occurring polymers, such as starch, cellulose, and lignin, were explored to develop blended and functionalized bioplastic formulations. Comparative evaluation revealed that these biomass-derived polymers possess favourable physical strength, thermal stability, and biodegradability under composting conditions. Life-cycle evaluation further indicated a significant reduction in greenhouse gas emissions and improved carbon recycling compared to fossil-derived counterparts. The study demonstrates that integrating agricultural residues into bioplastic production not only enhances waste valorization and rural bioeconomy but also supports sustainable material innovation for packaging, farming, and consumer goods industries. These findings position agriculture-based biodegradable polymers as a critical component of circular bioeconomy strategies, contributing to reduced plastic pollution and improved environmental sustainability. Full article

Integrated crop grazing systems can improve farm profitability due to enterprise complementarity. Utilizing the supply of N from legumes, livestock manure, and plant residues will result in improving grain yield and quality. A long-term 12-year integrated systems study evaluated continuous spring wheat (HRSW-CTRL) with spring wheat (HRSW-ROT) grown in a five-crop rotation: (1) spring wheat, (2) seven-species cover crop, (3) forage corn, (4) field pea/forage barley mix, and (5) sunflower. Yearling beef cattle steers grazed the field pea/forage barley mix, unharvested corn, and a seven-species cover crop. Spring wheat was marketed as a cash crop. Contrary to expectations, HRSW-ROT did not significantly increase grain yield or improve quality over HRSW-CTRL. Improved soil fertility was observed in the HRSW-ROT plots throughout the study relative to SOM, N, P, and K. However, the rotation with grazing management significantly reduced input costs but resulted in negligible gross and net returns over the 12-year period. Year-to-year weather variability was the cause of the differences between the two production management methods. Full article

Lignocellulosic biomass wastes are renewable carbon resources that can be available for conversion into biofuels. There is a growing interest in utilizing a broader range of alternative biomass feedstocks such as agri-crop residues aside from the traditional forest-origin wood residues for fuel pellet production. However, crop residues typically have low and inconsistent fuel quality. This paper investigated the effectiveness of the combined steam explosion and water leaching pretreatment techniques to upgrade the fuel properties of wheat straw. The experimental treatments involved auto-catalyzed steam explosion and acid-catalyzed steam with and without subsequent water leaching. Using steam explosion catalyzed by dilute H₂SO₄ at a low concentration of 0.5 wt%, results showed the highest ash, Si, and Ca removal efficiencies of 82.2%, 91.1%, and 74.3%, respectively. Moreover, there was significant improvement in fuel quality in terms of fuel ratio (0.34) and calorific value HHV (21.9 MJ/kg), as well as a pronounced increase in the comprehensive combustibility index at the devolatization stage, indicating better combustion characteristics. Overall, the results demonstrate that with adequate pretreatment, the quality of agri-pellets derived from wheat straw could potentially be on par with wood pellets that are utilized for heat and power generation and residential heating. To mitigate the dry matter loss due to steam explosion, future studies shall consider using the process effluent to produce biofuel. Full article

Suspension fertilizers offer high concentration, excellent fluidity, an eco-friendly production process, and ease of precise and even application, making them ideal for modern fertigation systems. However, stability remains a significant challenge. This study aims to develop an organic value-added suspension fertilizer (VSuF) based on the filtrate of acid–base-treated soybean residue, which can ensure stability during transportation and storage while promoting efficient nutrient utilization in agriculture. The stabilizers were optimized by comparing the effects of various types and dosages on particle size, zeta potential, viscosity, and thixotropy of the suspension fertilizer. Meanwhile, the stability and agricultural effects of the fertilizer were evaluated. Results showed that with 0.40% sodium lignosulfonate, 0.40% xanthan gum, and 0.20% organic silicon defoamer, VSuF remained stable during centrifugation (2000 r·min⁻¹, 30 min) and storage at 0 °C and 50 °C for 14 days. Additionally, agricultural evaluation indicated that VSuF significantly increased the dry weight and phosphorus uptake of crop shoots by 17.40% and 21.00%, respectively, relative to the solid fertilizer without the value-added compound. Meanwhile, VSuF enhanced the fresh weight, length, and surface area of crop roots by 83.10%, 74.47%, and 69.34%, respectively, along with shoots’ phosphorus uptake by 19.80%, compared to the glucose value-added solid fertilizers. Full article

The limited availability of phosphorus (P) in soil poses a critical constraint on agricultural productivity, and sustainable P fertilization practices are of great importance for crop production. In this study, we developed a novel dual-function granular material (RMG) derived from red mud, a waste residue from the aluminum industry. This material is capable of adsorbing P in P-rich soils and releasing P in P-deficient soils, thereby enabling the sustainable use of red mud and P fertilizer. The influences of RMG on the migration and transformation of P in soil were investigated. Application of RMG significantly increased the critical threshold for P leaching, thereby effectively mitigating P loss. In the initial stage of leaching, P in the leachate was present predominantly as particulate phosphorus, whereas molybdate-reactive P became the dominant form in later stages. With increasing RMG dosage, the pH of the leachate rose while the total phosphorus concentration declined, indicating that alkaline components in RMG promoted the adsorption and precipitation of phosphates in soil. The release behavior of P from P-enriched RMG was also examined. The results showed that the total soil P content increased progressively with higher RMG dosage and longer cultivation duration. Elevated temperature and soil moisture content were found to enhance the release and migration of P from RMG into the soil. SEM-EDS analyses revealed that released components (e.g., Ca²⁺ and Fe³⁺) from RMG formed relatively stable complexes with free phosphates. Moreover, adsorption of P onto the RMG surface further facilitated its migration and transformation within the soil. The research findings provide valuable insights for the simultaneous pollution remediation and resource utilization of red mud and phosphorus. Full article

Grain crops are regarded as fundamental to China’s agricultural production and food security. Effective control of nocturnal phototactic pests is essential for ensuring crop yields and achieving sustainable agricultural development. However, traditional solar insecticidal lamps often suffer from low energy utilization efficiency, dynamic switching control schemes, and poor adaptability in multi-pest coexistence scenarios. A multi-period intelligent switching control optimization scheme based on integrating a multi-pest phototactic rhythm is proposed, focusing on Cnaphalocrocis medinalis and Chilo suppressalis in rice fields. By considering the phototactic behavioral rhythm, energy consumption patterns, and residual energy levels, the proposed scheme dynamically optimizes the switching cycles of solar insecticidal lamps to maximize pest control effectiveness and energy efficiency. The rhythm modeling approach and dynamic adjustment mechanisms are employed to accurately align insecticidal working hours with varying pest activity patterns, thereby improving the pest control effectiveness of IoT-based solar insecticidal lamps. Simulation experiments demonstrate that, compared to traditional switching control schemes, the dynamic switching control scheme improves the average insecticidal rate by 17.7%, increases the effective insecticidal energy efficiency value by approximately 66.1%, and enhances the energy utilization rate by about 38.5%. The proposed dynamic switching control and intelligent energy management scheme not only improves the precision of pest control and energy utilization but also promotes the more efficient application of networked solar insecticidal lamps in smart agriculture. This work provides theoretical support and practical reference for intelligent pest control in complex agricultural environments, promoting the precision and sustainability of pest management practices. Full article

Since the 1980s, Mexico has undergone profound economic and political transformations grounded in neoliberalism, reflected in the opening of the agri-food sector. As a result, imports of powdered milk increased, consolidating a corporate agri-food regime that has exerted structural pressure on small-scale dairy producers, promoting processes of de-peasantization and proletarianization. This study analyzes the evolution of family dairy farming in Santa Elena, Michoacán, México, with the aim of identifying and analyzing the principal components of family structure, economic and productive rationality that have been maintained over time, and how they are modified to adapt the family dairy farming to the context of contemporary capitalism. It hypothesizes that changes in the main components of family structure, and productive and economic rationality of family dairy households are the result of strengthened peasant characteristics. Based on the analysis of census data of household production units (HPUs) in 2002 and 2018, a Principal Component Analysis (PCA) was conducted to characterize and identify changes in the productive and economic structure of these units. The component with variables linking family dairy farming to the market was the most significant and consistent over time. The remaining components varied. Feeding variables formed the second most important component in both studies, which changed its structure in 2018, focusing on minimizing operating costs and utilizing crop residues for feed. It is concluded that family dairy farming in Santa Elena, Michoacán, has adapted to the conditions of global agri-food capitalism without a clear transition toward productive intensification or specialization. Instead, family dairy farming has persisted through diversification strategies, self-management, and access to local markets, demonstrating the persistence of peasant economic rationality. Full article

The utilization of lime kiln flue gas for producing CO₂-based fertilizer represents an emerging pathway to link industrial emission reduction with sustainable agricultural development. This review summarizes recent progress in CO₂ capture, purification, and application technologies, with a focus on their suitability for protected agriculture. It discusses the advantages of high CO₂ concentration and low-temperature tail gas, the challenges posed by impurities, and the technological routes for efficient CO₂ recycling. The review highlights that controlled CO₂ fertilization can significantly enhance crop growth and quality, while the effects of residual gases and uneven distribution require further investigation. Future research should prioritize the development of scalable, low-cost adsorbents and precision fertilization systems based on digital twin technologies to promote the integration of industrial carbon recycling and smart agriculture. Full article