Search Results (3,257)

Municipal organic waste management remains a major challenge for sustainable urban development, particularly in regions requiring decentralized treatment alternatives that reduce landfill dependency and promote circular resource recovery. This study compared Takakura composting and vermicomposting for the stabilization of municipal organic waste under decentralized operational conditions in the Ecuadorian Amazon and developed a Composite Circular Resource Recovery and Process Performance Index (CRRPPI) to evaluate resource recovery efficiency. Municipal organic waste was treated through Takakura composting, vermicomposting, and uncontrolled decomposition (control). Operational performance was assessed using material conversion efficiency, process productivity, nutrient recovery efficiency, nutrient productivity, and final physicochemical characteristics. These indicators were integrated into the CRRPPI framework to provide a multidimensional assessment of circular resource recovery performance. Takakura composting showed the highest operational efficiency, achieving material conversion efficiencies of up to 0.80, process productivity values of 1.23 kg day⁻¹, and superior nutrient recovery efficiencies for nitrogen (0.835), phosphorus (0.730), and potassium (0.880). The highest CRRPPI values were obtained for Takakura treatments (0.835–0.842), while vermicomposting showed intermediate performance, and the control treatment presented the lowest resource recovery efficiency (0.216). Sensitivity analysis confirmed ranking stability under ±20% weighting variations, and ANOVA followed by Tukey’s HSD test identified significant differences among treatments (p < 0.05). The results indicate that Takakura composting is an effective strategy for decentralized municipal organic waste valorization and nutrient recirculation. Furthermore, the proposed CRRPPI provides a practical exploratory framework for integrated evaluation of biological stabilization technologies by simultaneously considering operational performance and circular resource recovery. Full article

Due to large-scale macroalgal blooms, nutrient enrichment, and changes in ocean circulation brought on by climate change, beach-accumulated seaweed (BAS) has quickly become a global environmental and waste-governance concern. Despite degradation and contamination during beach stranding, BAS retains valuable bioactive compounds, including sulfated polysaccharides, phlorotannins, pigments, proteins, peptides, and lipids, which exhibit anti-inflammatory, antioxidant, antimicrobial, antiviral, immunomodulatory, anticancer, and metabolic regulatory activities. This review critically evaluates BAS as a sustainable bioresource by integrating current knowledge on biomass composition, degradation-associated challenges, bioactive properties, valorization pathways, advanced extraction technologies, safety validation, regulatory considerations, and emerging commercialization opportunities. Attention is given to sustainable valorization pathways, ranging from composting and bioenergy production to the recovery of high-value bioactives through enzyme-assisted, green, and advanced extraction technologies. The review further discusses policy and regulatory gaps, contamination challenges, safety validation requirements, and life-cycle sustainability considerations that currently limit industrial adoption. Finally, emerging opportunities involving metabolomics, microbial bioprocessing, artificial intelligence, automation, and nanotechnology are explored as future directions for transforming BAS into a standardized and economically viable feedstock within the circular blue bioeconomy. Establishing harmonized regulatory frameworks and integrating BAS management with Sustainable Development Goals (SDGs) 12 and 14 will be critical for enabling sustainable resource recovery and long-term coastal resilience. Full article

Cadmium contamination of soils poses a global threat to food security and ecosystem stability. Soil bacteria play a key role in mitigating Cd-induced stress, and their adaptive capabilities can be modulated by the application of organic amendments such as compost, fermented bark, or preparations containing humic acid. This article presents the results of studies on soil bacterial communities using culture-dependent and next-generation sequencing approaches. Based on the obtained data, colony development indices and ecophysiological diversity indices were determined for organotrophic bacteria and actinobacteria. Alpha and beta diversity of bacteria were also assessed, common and unique genera occurring in the studied soils were identified, and the predicted metabolic functions of microorganisms were determined. It was found that cadmium reduced the abundance of organotrophic bacteria and actinobacteria by 54.5% and 12.9%, respectively, compared to the control, resulting in a shift in the bacterial community structure from r-strategists toward K-strategists. Humic acid increased the abundance of organotrophic bacteria and actinobacteria by 42.8% and 57.3%. Compost most effectively mitigated cadmium effects by stabilizing the colony development index and bacterial ecophysiological diversity. Cadmium strongly altered the soil bacterial microbiome, reducing the abundance of Actinomycetota while increasing that of Pseudomonadota and Bacteroidota. The application of organic amendments influenced the bacterial response to Cd²⁺-induced stress. Fermented bark was associated with an increased abundance of Sphingomonas, whereas compost was associated with an increased abundance of Cellulosimicrobium. Although none of the organic amendments affected the overall diversity index under these conditions, compost improved the evenness and ecological stability of the bacterial community. The dominance of aerobic chemoheterotrophs involved in the carbon cycle and the degradation of organic compounds was demonstrated. Compost most effectively supported biogeochemical processes. Full article

Approximately 30% of the food produced worldwide is wasted, and a substantial share of municipal food waste still contains non-biodegradable packaging material after sorting. This study investigated an aerobic biodrying process for reducing the moisture content of mixed food-waste fractions, containing varying proportions of green biomass, vegetables, kitchen waste, and packaging-derived plastics, in order to increase their calorific value and obtain a refuse-derived fuel (RDF). Four substrate variants (K1–K4, including a control without added plastics) were biodried in laboratory-scale bioreactors. Process temperatures exceeded 70 °C in all variants, and the addition of plastics increased both the cumulative and the average temperature relative to the control. The plastic fraction recovered after biodrying showed the largest increase in calorific value, reaching over 15 MJ∙kg⁻¹, while the AT4 respiration activity of the separated compost fraction decreased to around 10 mg O₂ g⁻¹ DM in all variants, indicating good storage stability. The results suggest that pre-treated plastics did not adversely affect the biodrying process and, owing to their structuring properties, may support biological decomposition of the remaining biomass; these preliminary, single-run findings should be confirmed in replicated trials. Full article

In protracted humanitarian crises, solid waste management (SWM) becomes a major challenge due to limited resources, inadequate infrastructure, and competing response priorities. Waste generated in humanitarian settings typically consist of heterogeneous streams, where plastics, biodegradable fractions, and packaging materials represent the dominant components. Proper management of this waste is essential to reduce health risks and environmental impacts on local communities. Within this framework, sustainable bio-based alternatives and compostable solutions represent promising alternatives. The EU-funded Bio4HUMAN project promotes the integration of innovative bio-based solutions aligned with humanitarian and sustainability goals. An exploratory assessment focused on analyzing waste production, material composition, and handling practices in two case study locations in Sub-Saharan Africa (Democratic Republic of Congo (DRC) and South Sudan (SS)). The results indicate that humanitarian waste cannot be clearly distinguished from household or commercial waste, as streams are typically mixed. Waste composition is dominated by organic matter (43–65%), followed by plastics (15–33%), while other fractions such as paper, glass, metals, and textiles are less significant. Further insights into challenges and opportunities were obtained through a combination of quantitative surveys (n = 29), qualitative interviews with key informants (KIIs) (44) and group discussions sessions (FDG) (9), direct observations, and literature review. Subsequently, a scoping approach was applied to map and classify suitable sustainable solutions into two main categories: bio-based products (BBPs) and organic waste valorization technologies. These were assessed through life cycle assessment (LCA) in accordance with ISO 14040 and 14044, applying SimaPro v.10.2.0.3 software and the Ecoinvent 3.10 database, and compared against fossil-based alternatives. This study compares two case scenarios: a HDPE oil bottle versus PLA alternative (functional unit 6 L), and PE water container versus PLA alternative (functional unit 10 L). For the oil bottle, PLA shows a lower carbon footprint (1.33 kg CO₂-eq) than HDPE (2.37 kg CO₂-eq). In contrast, for the water container, PLA performs worse (2.22 kg CO₂-eq) compared to PE (1.59 kg CO₂-eq), due to higher material demand. The results suggest that benefits are context-dependent and most evident for lightweight products with high leakage risks, particularly when composting infrastructure is accessible. This study advances previous work on humanitarian SWM by integrating field-based waste flow characterization with context-specific screening and life cycle assessment of bio-based alternatives, providing quantitative evidence on the conditions under which these solutions can effectively reduce environmental burdens in protracted crisis settings. Full article

Soil amendments are widely applied for water conservation in urban turfgrass, yet whether establishment-phase benefits persist into a mature-stand remains unclear. This study evaluated biochar, biosolids, and greenwaste on tall fescue (Schedonorus arundinaceus) over a 108-day mature-stand trial under deficit (50% ET₀) and moderate (85% ET₀) irrigation, both below full replacement. Canopy performance was assessed by visual quality and NDVI, with van Genuchten soil-water retention modeling. Unlike the establishment-phase advantages reported for the organic amendments in Part I, the second-year results reversed sharply: moderate biochar (12.36 t ha⁻¹) was most hydraulically stable, holding the highest plant-available water (PAW ≈ 0.18 cm³ cm⁻³, above the control and organic amendments) and the most stable canopy. High-rate biochar (24.71 t ha⁻¹) underperformed the control under deficit irrigation, indicating constraints beyond water retention at the highest rate. Greenwaste and biosolids raised volumetric water content but provided lower PAW than moderate biochar. For greenwaste, a reduced field capacity offset this; for biosolids, an elevated permanent wilting point limited the extractable fraction. Biosolids failed to maintain acceptable quality even under the 85% ET₀. Because first-year success does not guarantee mature-stand resilience, amendment stability and rate optimization, rather than application volume, emerge as long-term management priorities under water-limited conditions. Full article

Mulching is an agronomic practice that improves orchard soil and promotes root growth. To investigate the regulatory effects of different mulching materials on soil properties, microbial communities, and root function in apple orchards, eight treatments were established: clean tillage (CK), organic fertilizer mulching (OFM), chopped corn straw mulching (SM1), chopped and bundled corn straw mulching (SM2), intact corn stover mulching (SM3), composted apple branch mulching (BM), horticultural ground cover fabric mulching (FM), and weed mulching (WM). The results showed that OFM, BM, SM1, and SM3 exhibited effective cooling effects during summer. During the peak root-flush period, OFM, SM3, and BM significantly reduced soil bulk density, increased porosity, enhanced soil organic matter and available nutrient contents, and elevated the activities of soil sucrase, urease, and catalase. Moreover, these treatments promoted the accumulation of carbohydrates and the uptake of mineral nutrients in roots. OFM and SM3 significantly increased the Simpson index of both soil bacterial and fungal communities, while BM improved the beta diversity of bacterial and fungal communities. OFM, SM3, and BM can effectively improve soil physicochemical properties, optimize microbial community structure, and enhance root nutrient uptake. It is recommended as a mulching measure for soil in northern apple orchards. Among the eight treatments evaluated, OFM, SM3, and BM exhibited superior performance in improving soil physicochemical properties, promoting root function, and enhancing microbial community diversity. Therefore, the findings of this study provide an effective soil management strategy for apple orchards in the cold northern regions of China. Full article

This study investigates the influence of PLA flowability and talc content on the performance of compostable thermoplastic starch/poly(butylene succinate) (TPS/PBS)-based systems for rigid applications. Different PLA grades with varying melt flow index (PLA23, PLA8 and PLA70) and talc contents (0, 5 and 10 wt%) were incorporated. Twelve formulations were compounded by twin-screw extrusion and processed by injection moulding. FTIR confirmed the coexistence of TPS, PBS and PLA phases without evidence of chemical interactions. Morphological analysis showed that PLA flowability plays a key role in phase distribution, with higher-flow PLA promoting improved dispersion and interfacial adhesion, while talc addition (5 and 10 wt%) increased structural heterogeneity; at higher loadings, particularly, DSC analysis revealed that talc acted as a nucleating agent for the PBS phase, increasing crystallisation temperatures from approximately 73 °C to 81 °C depending on formulation. Mechanical results showed that Young’s modulus increased from approximately 1.4 GPa to 2.7 GPa with decreasing PLA flowability and increasing talc content. Formulations containing low-flow PLA reached tensile strengths close to 32 MPa, although elongation at break decreased to values near 2%. In contrast, high-flow PLA formulations exhibited a more balanced mechanical response, with elongation values up to approximately 8%, associated with improved phase dispersion. Hybrid PLA systems showed intermediate behaviour, reaching elongations up to 22% while maintaining modulus values around 1.8 GPa. Talc provided additional reinforcement but reduced deformation capacity. HDT values remained relatively constant, indicating limited improvement in thermomechanical resistance despite increased stiffness. These results demonstrate that the combined control of PLA molecular characteristics and talc content enables tuning of the mechanical and thermomechanical performance of TPS/PBS/PLA/talc systems for rigid packaging applications. Full article

Sustainable agriculture increasingly relies on organic amendments that integrate circular economy principles. Municipal Solid Waste (MSW)-derived compost (MSW-compost) represents a promising candidate as soil amendment in viticulture, yet its impact on soil microbiota remains poorly investigated. This study assessed the effects of MSW-compost application on the bacterial microbiota of a Mediterranean vineyard soil over a twelve-month period, comparing two application methods (surface mulching and tillage incorporation). Soil DNA was analyzed by 16S rRNA gene metabarcoding, complemented by functional prediction (Picrust2) and the Tea Bag Index to assess soil decomposition activity. MSW-compost significantly increased alpha-diversity and affected beta-diversity (p = 0.001) of the microbiota, regardless of the application method, with significant effects persisting throughout the entire observation period despite a clearly diminishing trend. Devosia emerged as the hub taxon of the co-occurrence network and was increased by compost addition. MSW-compost application mode remarkably affected the microbial network, with mulched treatment leading to a more complex, denser, and more interconnected network. While a similar number of taxa were increased or decreased, functional prediction revealed a notable enrichment of metabolic pathways, both synthetic and degradative, in the MSW-compost amended samples; this finding was supported by the enhanced red tea decomposition data (p = 0.007). Our results indicate that MSW-compost acts as a beneficial soil amendment, simultaneously enhancing microbial diversity and soil decomposition activity. This study provides novel evidence supporting the use of MSW-compost as a sustainable tool for improving soil microbiological quality in productive vineyards. Full article

The transition to a circular economy requires the safe management of sewage sludge through nutrient and energy recovery. However, pharmaceuticals and personal care products (PPCPs) present a significant challenge. These compounds tend to accumulate in sludge via sorption, shifting the environmental burden from the aqueous phase to the sludge. This manuscript provides a comprehensive review of the scientific literature on technical alternatives for valorizing sewage sludge and removing emerging contaminants. The study evaluates the limitations of conventional biological methods, such as anaerobic digestion and composting, which exhibit variable efficacy and are often insufficient to degrade some commonly used pharmaceuticals. On the contrary, thermal treatments (pyrolysis, gasification, and hydrothermal processes) are considered robust alternatives capable of achieving the high removal of chemical compounds. Furthermore, the article emphasizes the innovative potential of utilizing carbon-based byproducts (biochar and hydrochar) as adsorbents, catalysts, or soil amendment to enhance the removal of PPCPs within the treatment infrastructure itself. The integration of advanced thermal technologies is essential to mitigate the risks of contaminant transfer to the food chain and ensure a safe and sustainable nutrient cycle. Full article

Sustainable agricultural technologies are essential to respond to environmental and social pressures, ensuring the maintenance of global food security. Therefore, there is an urgent demand for more sustainable agricultural practices that promote soil quality, as this factor directly impacts the global economy. Agricultural yield is directly associated with soil health and fertility. The use of organic waste serves as a source of essential nutrients for plants, increasing soil organic matter, contributing to the improvement of soil physical and chemical properties, as well as increasing crop yield. Based on this context, this research aimed to evaluate the effects of incorporating organic waste aiming to mitigate the oxidative damage in maize plants grown under different levels of soil fertility (low, average, and high), evaluating soil and plant, more specifically chemical, physiological, biochemical, and morphological responses. In soil, organic waste promoted significant increases in the activities of arylsulfatase and β-glucosidase and improved the chemical parameters, including cation exchange capacity, soil organic matter, base saturation, and sum of bases. The application of organic waste, regardless of fertility level, improved the nutritional status in maize plants, increased concentrations of photosynthetic pigments, maximized the photochemical efficiency and photosynthesis rate. In plant metabolism, the results demonstrated that organic waste promoted significant increases in plant antioxidant defense, including superoxide dismutase, catalase, ascorbate peroxidase, and peroxidase, minimizing the oxidative stress on photosynthetic machinery, especially in plants cultivated on soil with low fertility. Therefore, this research proves that organic waste mitigates the negative impacts associated with nutritional starvation, improves soil health and fertility, favors the maintenance of redox metabolism, and stimulates photosynthesis in maize plants cultivated in low-fertility soil. Full article

Conventional composting struggles with slow fermentation and low humification efficiency in managing global food waste. While hyperthermophilic composting (HTC, >80 °C) can enhance efficiency, the microbial and metabolic drivers of accelerated humification remain unknown. Multi-omics analysis revealed that microbial restructuring during the HTC cooling stage (30–80 °C) triggers metabolic reprogramming. Enriched thermophiles (e.g., Gordonia, Cryptosporangium, Limnochordia) redirect carbon flux toward anabolism via upregulated glycolysis/gluconeogenesis and aromatic amino acid biosynthesis, while suppressing the TCA cycle. This redirected carbon flux accelerated lignocellulose degradation (2.6–3.7-fold), boosted humic acid synthesis (by 50%), and increased the humification index (by 76%). Critically, it promoted the condensation of lignin-derived phenolics with amino acids and Maillard-mediated polymerization, increasing aromatic precursors by 161%. Structural equation modeling demonstrated a strong association between microbial restructuring and humic substance formation, explaining 96% of the total variance through metabolic regulation. These mechanistic insights enable the design of high-efficiency composting systems for simultaneous waste valorization and stable humic substance production. Full article

Alfalfa (Medicago sativa L.) is widely recognized as a major forage crop, yet its role as a multifunctional biological input in sustainable horticultural production remains underexplored. This review evaluates alfalfa as a biological nitrogen source, organic fertilization resource, and biofertilizer-supporting crop within vegetable, medicinal, and perennial horticultural systems. Due to its high capacity for biological nitrogen fixation, alfalfa can supply substantial amounts of plant-available nitrogen, reducing dependency on synthetic fertilizers and supporting environmentally sound nutrient management. When used as green manure, cover crop, intercrop, mulch source, compost feedstock, or processed organic fertilizer, alfalfa enhances the soil organic carbon (SOC), improves soil structure, and increases the water-holding capacity properties particularly critical in intensive horticultural production. Higher SOC levels also contribute to the improved tolerance of horticultural crops to drought and heat stress through enhanced soil moisture retention and rhizosphere buffering. Alfalfa-based organic inputs stimulate rhizosphere microbial biomass, enzymatic activity, and functional genes associated with nitrogen cycling, strengthening plant–microbe interactions that underpin biofertilizer effectiveness. Evidence from vegetable and perennial systems indicates that alfalfa-derived amendments and rotations increase soil nitrogen availability, support yield stability, and improve soil health over the long-term. In orchards and vineyards, alfalfa cover cropping contributes to carbon sequestration, erosion control, and enhanced soil biological functioning. Overall, alfalfa emerges as a strategic species for integrating organic fertilization and biofertilizer-based approaches into modern horticultural systems, supporting reduced mineral fertilizer inputs while sustaining productivity, soil health, and environmental quality. Full article

The management of livestock manure is associated with substantial ammonia (NH₃) emissions and the accumulation of emerging contaminants, including antibiotics, antibiotic resistance genes (ARGs), and microplastics, posing risks to environmental quality and public health. Biochar has emerged as a promising strategy for mitigating gaseous emissions and reducing contaminant mobility during manure storage and composting processes. This review synthesizes recent research on the application of biochar in livestock manure management systems, focusing on NH₃ emissions, antibiotic degradation, ARG reduction, and microplastic removal. Particular attention is given to the effectiveness of biochar in mitigating pollutants during manure storage, housing operations, and composting processes. Across the literature, reported NH₃ mitigation efficiencies vary widely, from negligible effects to reductions exceeding 90–97%, depending on feedstock type, pyrolysis conditions, particle size, and application strategy. Biochar also promotes antibiotic degradation and ARG mitigation, with reductions of up to 98% reported in composting systems. Emerging evidence further suggests that biochar can reduce microplastics by approximately 15–64% in sludge composting. Plant-derived and chemically modified biochars generally outperform manure-derived biochars due to higher surface area, cation exchange capacity, and greater abundance of functional groups. The review highlights that activation treatments, co-composting strategies, and microbial interactions are key factors controlling pollutant mitigation efficiency. Despite promising outcomes, large-scale application remains limited by economic constraints, variability in biochar properties, and the lack of long-term field-scale validation. Future research should prioritize standardized production protocols, field implementation studies, and integrated environmental and economic assessments to support the practical adoption of biochar in sustainable livestock waste management systems. Full article

Back-mixing has been widely applied during practical composting to initiate the process and improve compost product quality. However, for antibiotic mycelial residue (AMR), a fermentation by-product containing residual antibiotics, the ecological safety of this treatment remains unclear. In this study, pleuromutilin mycelial residue (PMR) was subjected to a 35-day aerobic composting experiment with a back-mixing treatment (T group) and the conventional composting group (CK group) to evaluate composting performance and antibiotic resistance risk. The results demonstrated that the T group exhibited more rapid heating and a higher degree of humification. Additionally, the T group not only exhibited faster pleuromutilin degradation, reaching below the detection limit 3 days earlier than in the CK group, but also achieved up to a 3.1-fold reduction in antibiotic resistance genes (ARGs) and a 93.2% overall reduction in mobile genetic elements (MGEs). Redundancy analysis (RDA), variance partitioning analysis (VPA), and co-occurrence network analysis indicated that microbial community structure appeared to be more strongly associated with ARG variation than MGEs under the tested conditions. Overall, back-mixing accelerated pleuromutilin degradation and enhanced PMR composting performance, while no substantial enrichment of the detected ARGs was observed under the tested composting conditions. This study provides a scientific basis for the safe resource utilization of AMR. Full article