Search

Organic by‐product and waste streams generated from agriculture and food production are important future feedstocks for manufacturing chemicals, polymers, and other materials in a circular bioeconomy. These waste streams are currently underutilized and under‐explored in the context of biomanufacturing though much funding and infrastructure have been made available for their use in energy generation. The natural ability of microorganisms to utilize compounds in organic wastes, coupled with advances in engineering biology that enable scientists to manipulate biological systems to produce chemicals, polymers, and materials, and improve upon those processes, present a promising technological approach to the utilization of these waste streams as feedstocks. However, the characteristics of waste streams make them challenging to incorporate into biomanufacturing processes. These challenges can be addressed with additional advances in engineering biology research and thoughtful approaches to process development. Research and process development around the use of existing, localized waste streams present distinct benefits and raise interesting considerations, and are important undertakings. These activities will be as complex as the waste streams targeted; as such, coordination of efforts across relevant agencies and organizations, and collaborations between researchers, waste generators, customers, and other stakeholders will be critical to their success. To make meaningful and rapid contributions towards utilization of organic wastes as biomanufacturing feedstocks we recommend: (1) The National Institute of Food and Agriculture (NIFA) at the US Department of Agriculture should incorporate into existing programs the development of organic waste conversion into chemicals, polymers, and other materials using engineering biology and, if possible, establish new programs focused on this area; and (2) NIFA should oversee, coordinate, and publicize collaborative efforts that include federal agencies, state and regional agricultural research centers and cooperatives, and program‐related infrastructure. [ABSTRACT FROM AUTHOR]

Organic waste utilization stands as a pivotal approach to ecological and economic sustainability. This study aimed to assess the stability, maturity, and evolution of co-composts comprising various blends of green waste (GW) and sheep manure (SM). Employing a diverse array of physico-chemical and biological parameters, we investigated the co-composting process over 120 days. Three types of garden waste (mixture of green waste (MGW), fallen leaves (FL), and grass cutting (GC)) were utilized. The results revealed significant compost transformation, evident by odor and insect absence and a shift to dark brown coloration, indicating maturation. The compost C2, derived from FL, exhibited superior soil amendment potential. Significantly, it exhibited a pH level of 6.80, an EC of 2.45 mS/cm, and an OM content of 55%, along with a C/N ratio of 16.15. Analysis of the macronutrients revealed values of 1.98% for TN, 3.22% for TP, and 0.61% for K. Crucially, the compost showed no phytotoxic effects and boasted a high GI of 94.20% and a low respiration rate of 4.02 mg/50 g, indicating its stability and appropriateness for agricultural application. Our findings underscore compost's potential as an eco-friendly soil amendment, offering valuable insights for sustainable agricultural management and supporting the circular economy. [ABSTRACT FROM AUTHOR]

Understanding dechlorination behavior is important in the generation of environmentally benign precursors from chlorinated plastics by thermal treatment. In this work, the real-time chlorine distribution during hydrothermal treatment (HTT) of chlorinated plastics was first studied by installing an online sampler on the exhaust pipe of the reactor. Linear low-density polyethene (LLDPE), polypropylene (PP), and polyvinyl chloride (PVC) were selected as parent materials to investigate the dechlorination behavior within a broad temperature range of 175°C–280°C for 30 min, and 205°C–235°C for 15–60 min. The results showed that the existence of LLDPE and PP did not change the chlorine release form but affected the chlorine distribution and dechlorination efficiency (DE). Below 220°C, the existence of LLDPE, PP, and LLDPE/PP showed neglectable effect on the PVC dechlorination behavior and efficiency. A positive synergistic effect on dechlorination was observed at the HTT temperature of 220°C for mixed plastics. DE was improved by 11.90%, 9.50%, and 10.30% for LLDPE/PVC, PP/PVC, and LLDPE/PP/PVC, respectively under 220°C for 30 min. Further increasing HTT temperature, the molten LLDPE and PP could cover PVC, thus hindering the escape of HCl. Kinetic analysis shows that the dechlorination process followed the first-order reaction, controlled by chemical reactions, and higher temperatures could accelerate chlorine removal. This work provides a theoretical basis for the harmless disposal and resource utilization of chlorinated organic waste. [ABSTRACT FROM AUTHOR]

Purpose: The growing adverse effects of agrochemicals on environmental health and safety warrant an examination of ecologically safe alternatives for weed control. The objective of this study was to determine the effect of rice-husk waste on the growth performance and weed management (WM) of Ocimum sanctum. Method: In a randomized complete block design with three replications, nine weed management (WM) methods were assessed. These methods included black, red, and transparent polyethylene mulches; rice-husk; sawdust; hoe-weeding at 30 days after transplanting (DAT); a one-time application of 0.2 kg/ha Haloxyfop-P at 30 DAT; daily weeding; and no-weeding. Data were collected on weed parameters and growth attributes of Ocimum sanctum. All data were subjected to analysis of variance. Results: The use of rice-husk mulch resulted in the most significant (p< 0.05) increase in plant height (41.70 cm), leaf number (206.80), branch number (50.50), stem girth (2.76 cm), and leaf yield (7.15 t/ha) of Ocimum sanctum compared to the other weed control methods. It was comparable to black polyethylene (BP) in these traits except in leaf number where BP recorded a lower value (165.00). BP mulch was significantly more effective in weed suppression as it recorded the least number of broad leaves (0.00), sedges (0.00) weed biomass (0.00), and the highest weed control efficiency (WCE) (100%) at 10 WAT. The treatments ranked BP>Daily-weeding>Hoe-weeded>Rice-husk>Haloxyfop-PEHS>Redpolyethylene> Sawdust>Transparent-polyethylene>Control in WCE at 10 WAT. Conclusion: The study revealed that rice-husk mulch was the most effective in enhancing the growth and yield attributes of Ocimum sanctum, ranking fourth in weed control efficiency (WCE) at 72.60%, following black polyethylene (BP) mulch (100%), daily-weeding (96%) and hoe-weeded (95.7%). [ABSTRACT FROM AUTHOR]

Purpose: Integrating vermicompost and hydroponics in rice agriculture presents an innovative and sustainable solution for transforming organic waste into valuable resources. This review explores the possible utilization of organic waste into productive resources through vermicompost and hydroponics in rice agriculture. Method: A comprehensive literature review was conducted to investigate the potential use of vermicompost derived from organic waste for hydroponic rice agriculture. The available literature was analyzed to reveal and explore the various aspects of this application. Results: The literature review reveals that the utilization of vermicompost derived from organic waste in hydroponic rice agriculture holds the potential to evolve into effective strategies for reducing, reusing, and recycling organic waste. Vermicompost decreases used inorganic fertilizers, with studies reporting up to 30% reductions. The application of vermicompost can enhance plant growth by approximately 15% to 30% and positively impact increasing specific nutrients in plants. Using vermicompost can also increase the average crop yield by about 5% to 25% compared to other organic materials. Conclusion: This study found that integrating vermicompost and hydroponics represents a promising approach for transforming organic waste into productive resources. This integration allows organic waste to be effectively converted into nutrient-rich vermicompost and valuable growing medium in hydroponic systems. Scientific research has demonstrated the potential benefits of this approach, including improved nutrient availability, enhanced plant growth and yield, and reduced environmental impact. By combining the nutrient-rich properties of vermicompost with the precision and efficiency of hydroponic systems, farmers can achieve sustainable and resource-efficient crop production. [ABSTRACT FROM AUTHOR]

The article focuses on the significance of earthworms in soil fertilization and the reduction of chemical fertilizer use. Topics discussed include the role of earthworms in transforming organic waste into natural fertilizer, the process of vermicomposting, and the selection of suitable bedding materials and food sources for compost worms.

Municipal solid waste (MSW) compost represents a sustainable alternative to plastic film for mulching in viticulture. This study investigated the effects of MSW compost on vineyard soil properties, specifically focusing on side effects such as soil temperature and microbial decomposition activity, independently from its role in weed control. The experiment was conducted in a vineyard located in the Mediterranean region (Southern Italy), with six different mulching treatments: black polyethylene (PE) film, black and white biodegradable film, three different amounts of MSW compost (8, 15, and 22 kg plant−1), and a control without mulching. Weed growth was monitored to determine the optimal compost application amount. The 15 kg plant−1 treatment was selected for further analyses, as it did not significantly impact weed growth compared to the control. Results indicated that MSW compost mulching maintained lower soil temperatures compared to other treatments (up to 5 °C in the warmest hours) and reduced the amplitude of the thermal wave up to 50% compared to the non-mulched soil and even more compared to black film mulched soil, particularly during the warmest periods. This suggests that MSW compost can mitigate heat stress on plant roots, potentially enhancing plant resilience and preserving crop production also in stressful growing conditions. Microbial decomposition activity, assessed using the tea bag index, was higher in the MSW compost treatment during spring compared to the control, indicating temperature as a key driver for organic matter decomposition, but this effect disappeared during summer. These findings highlight the potential of MSW compost to support sustainable viticulture by reducing reliance on synthetic mulching materials and promoting environmental sustainability through the recycling of organic municipal waste. [ABSTRACT FROM AUTHOR]

There is an overlooked problem which increasing microbial abundance while reducing nitrogen loss during composting. This study investigated the viability of spent mushroom substrate (SMS) as conditioners in the aerobic composting of kitchen waste (KW) with cattle manure (CM). The variation of temperature, pH, C/N, organic matter, cellulose, hemicelluloses, germination index (GI), and microflora structure were explored to evaluate the potential in accelerating maturity and nitrogen fixation by SMS addition. The results showed that the addition of SMS accelerated the heating rate, prolonged the high temperature time, and decreased organic matter, hemicellulose, and cellulose by 17.49%, 23.61%, and 18.62%, respectively. The GI reached 105.86% with SMS addition, while 74.17% was found in control treatment after composting. SMS changed the microbial community composition and increased the species abundance. Proteiniclasticum, Clostridium XI and Azomonas were dominant bacteria, which increased the retention of nitrogen, promoted organic matter degradation and reduce compost time. The study can provide a feasible strategy for nitrogen fixation in the field of organic waste recycling. [ABSTRACT FROM AUTHOR]

In the era of deep space exploration, extremophile research represents a key area of research w.r.t space survival. This review thus delves into the intriguing realm of 'Space and Astro Microbiology', providing insights into microbial survival, resilience, and behavioral adaptations in space-like environments. This discussion encompasses the modified behavior of extremophilic microorganisms, influencing virulence, stress resistance, and gene expression. It then shifts to recent studies on the International Space Station and simulated microgravity, revealing microbial responses that impact drug susceptibility, antibiotic resistance, and its commercial implications. The review then transitions into Astro microbiology, exploring the possibilities of interplanetary transit, lithopanspermia, and terraforming. Debates on life's origin and recent Martian meteorite discoveries are noted. We also discuss Proactive Inoculation Protocols for selecting adaptable microorganisms as terraforming pioneers. The discussion concludes with a note on microbes' role as bioengineers in bioregenerative life support systems, in recycling organic waste for sustainable space travel; and in promoting optimal plant growth to prepare Martian and lunar basalt. This piece emphasizes the transformative impact of microbes on the future of space exploration. [ABSTRACT FROM AUTHOR]

In real-world situations, marine fish farms accommodate multiple fish species and cohorts within the farm, leading to diverse farm layouts influenced by cage dimensions, configurations, and intricate arrangements. These cage management practices are essential to meet production demands, however, farm-level complexities can impact model predictions of waste deposition and benthic impact near fish cages. This is of particular importance when the cages are used for integrated multi-trophic aquaculture (IMTA) with benthic feeders, where this waste not only affects environmental conditions but also provides a potential food source. The Cage Aquaculture Particulate Output and Transport (CAPOT) model incorporated multiple species, cohorts, and cage arrangements to estimate waste distribution from a commercial fish farm in the Mediterranean between October 2018 and July 2019. This spreadsheet model estimated dispersion for individual fish cages using a grid resolution of 5 m x 5 m. The study categorized discrete production periods for each fish cage every month, aligning with intermittent changes in biomass and food inputs due to different cage management practices throughout production. This approach facilitated the use of detailed input data and enhanced model representativeness by considering variations in cage biomass, food types, settling velocities, and configurations. Model outputs, represented in contour plots, indicated higher deposition directly below fish cages that varied monthly throughout fish production cycles. Deposition footprints reflected changes in cage biomass, food inputs, and farm-level practices reflecting this real-world scenario where aquaculture does not follow a production continuum. Moreover, cohort dynamics and cage movements associated with the cage management practices of the fish farm influenced the quantity and fate of wastes distributed around fish cages, revealing variability in deposition footprints. Clearly, these findings have important implications for the design of benthic IMTA systems, with species such as sea cucumber and polychaetes. Variability in waste deposition creates challenges in identifying where the benthic organisms should be placed to allow optimal uptake of waste to meet their food requirements and increase survivability. Evidently, models have an important role to play and this study emphasizes the need for representative input data to describe actual food inputs, cage biomass changes, and management practices for more representative farm-scale modelling and essentially to improve particulate waste management. To effectively mitigate benthic impacts through IMTA, models must quantify and resolve particulate waste distribution and impact around fish farms to maintain a balanced system with net removal of wastes. Resolving farm-level complexities provides vital information about the variability of food availability and quality for extractive organisms that helps improve recycling of organic wastes in integrated systems, demanding a more representative modelling approach. [ABSTRACT FROM AUTHOR]

In order to solve the problem of poor mixing effect of inclined spiral conveyor, this paper designed an inclined spiral and ribbon blade combination conveying device. The mechanics and kinematics analysis of the movement process of the material unit in each mechanism was carried out, on which key devices and components were designed based. Effects of the speed of main shaft (X1), the full coefficient (X2) and the angle of inclination (X3) on the mixing uniformity (Y1) and the residual rate of material (Y2) were explored. Three-dimensional quadratic regression orthogonal rotation central combination experiment method combined with response surface method was used to conduct experiments and explore the interaction effects of influence factors on indicators. A regression model of influence factors and evaluation indicators was established through the analysis of variance. The significant factors affecting Y1 were ordered of X3, X2, X1, and the significant factors affecting Y2 were ordered of X2, X1, and X3. In the interaction of factors, X1X2 had a significant impact on Y1 and Y2; X1X3 had an extremely significant impact on Y1; X2X3 had an extremely significant effect on Y1 and a significant impact on Y2. The optimal structure and working parameters combination were determined to be 50 rpm for the speed of main shaft, 60% for the full coefficient, and 19° for the angle of inclination, while the verification experiments demonstrated that the mixing uniformity and residual rate of material corresponding to the verification test were 90.37% and 5.31%, respectively. The inclined device with combined spiral and ribbon blade developed in this study meets the design requirements for the misprocess of the fertilizer utilization of agricultural organic wastes. [ABSTRACT FROM AUTHOR]

The black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae), is commonly used for organic waste recycling and animal feed production. However, the often inadequate nutrients in organic waste necessitate nutritional enhancement of black soldier fly larvae, e.g. by fungal supplementation of its diet. We investigated the amino acid composition of two fungi, Candida tropicalis (Castell.) Berkhout (Saccharomycetales: Saccharomycetaceae) and Pichia kudriavzevii Boidin, Pignal & Besson (Saccharomycetales: Pichiaceae), from the black soldier fly gut, and commercial baker's yeast, Saccharomyces cerevisiae Meyen ex E.C. Hansen (Saccharomycetales: Saccharomycetaceae), and their effects on larval growth and hemolymph metabolites in fifth-instar black soldier fly larvae. Liquid chromatography–mass spectrometry was used to study the effect of fungal metabolites on black soldier fly larval metabolism. Amino acid analysis revealed significant variation among the fungi. Fungal supplementation led to increased larval body mass and differential metabolite accumulation. The three fungal species caused distinct metabolic changes, with each over-accumulating and down-accumulating various metabolites. We identified significant alteration of histidine metabolism, aminoacyl-tRNA biosynthesis, and glycerophospholipid metabolism in BSF larvae treated with C. tropicalis. Treatment with P. kudriavzevii affected histidine metabolism and citrate cycle metabolites, while both P. kudriavzevii and S. cerevisiae treatments impacted tyrosine metabolism. Treatment with S. cerevisiae resulted in down-accumulation of metabolites related to glycine, serine, and threonine metabolism. This study suggests that adding fungi to the larval diet significantly affects black soldier fly larval metabolomics. Further research is needed to understand how individual amino acids and their metabolites contributed by fungi affect black soldier fly larval physiology, growth, and development, to elucidate the interaction between fungal nutrients and black soldier fly physiology. [ABSTRACT FROM AUTHOR]

The quantity of organic waste produced in China is enormous, and knowing the present situation of the country's total amount of organic waste and its nutritional supplies is important for both resource use and environmental safety. In order to analyze the potential for the utilization of organic wastes and the carrying capacity of the land, the current total amount of organic waste and its nutrient resources in China were estimated by reviewing Chinese statistical data and published literature. The study's objective was the production of major organic wastes (straw, livestock and poultry manure, rural human waste, sludge, and domestic organic waste) in China in 2021. The findings indicated that in 2021, its total resource would be 11.61×108 t, and its nutritional content would be 4075.24×104 t. In 2021, the nutrient contents of N, P2O5 and K2O in the total nutrient content of organic waste in China were 1571.43×104 t, 733.52×104 t and 1770.29×104 t, respectively. In 2021, the N nutrient content of China's organic waste accounted for 67.48% of the recommended N application, the P2O5 nutrient content accounted for 69.30% of the recommended phosphorus application, and the K2O nutrient content accounted for 131.09% of the recommended potassium application. From the perspective of China's overall scale, China has a large space for carrying and consuming livestock and poultry manure. When calculating the land carrying capacity based on nitrogen, the land carrying capacity index of China was 0.23, and when calculating the land carrying capacity based on phosphorus, the land carrying capacity index of China was 0.54. In general, China has a massive amount of organic waste materials and nutrients, with plenty of room for use. The current magnitude of farming places a minor strain on the land carrying capacity of animal manure. If the nutrient resource structure of China's organic waste remains unchanged and the entire amount is returned to the field, the nitrogen, phosphorus, and potassium nutrients in organic waste can satisfy 67.48%, 69.30%, and 100% of the nutrient requirements of various types of crops, respectively. [ABSTRACT FROM AUTHOR]

There has been an enormous information gap on product loss and waste management in the context of sustainable agricultural development. Therefore, this study aimed to explore the feasibility of alternative methods of recycling plant wastes generated in tomato production and to calculate the social cost of using inappropriate agricultural waste management methods in tomato production under greenhouses in Turkey. The research data were collected using questionnaires from 97 greenhouse farms growing tomatoes with soilless agriculture technology in Turkey. The feasibility of switching to the best recycling method was explored using partial budget analysis. According to the research results, on average, the amount of tomato plant waste generated in greenhouse farms was 1753 tons. 71% of vegetable waste was disposed of, while that of reused and recycled was 28% and 1%, respectively. The research also showed that farms that recycled their plant wastes would gain extra return by USD $ 5571 per year if the greenhouse farms switched to farm-level composting. The social cost of disposing of tomato plant wastes was USD $ 356,659 per year and USD $ 593 per hectare in Turkey. The study suggests designing a waste monitoring system via collaboration of state-private sector-NGO-university and putting it into practice to increase waste management efficiency. Checking the prevailing policy and policy instruments and establishing financial and technical infrastructure for recycling waste may be beneficial. [ABSTRACT FROM AUTHOR]

The use of HZSM-5 and modified catalysts for the pyrolysis of lignin to produce aromatics has been extensively investigated. But certain limitations including catalyst deactivation and high-cost modifications still exist. A magnetic field (MF) was used to assist Fe and HZSM-5 catalytic lignin pyrolysis for aromatics production in this study. Product composition analysis revealed that the monocyclic aromatic hydrocarbon (MAH) and benzene, toluene, ethylbenzene, and xylene (BTEX) contents exhibited an upward trend in correlation with the MF intensity. The introduction of a MF significantly affects the improvement of the BTEX yield. Under the conditions of 80 mT MF intensity, 500 °C temperature and 50 mL min−1 carrier gas flow rate, the MAH and BTEX contents reach 32.94% and 27.19%, while the BTEX yield reaches roughly 19.55 mg g−1. Compared to no MF, these values rose by about 1.28, 1.36, and 1.94 times, respectively. Characterization results from XRD, XPS, TPO, N2 adsorption–desorption, and NH3–TPD tests showed that the MF facilitated the deoxidation and fragmentation of macromolecular oxygenates on the surface of Fe, promoting the ingress of smaller molecular compounds into the pores of HZSM-5 and boosting MAH production. Simultaneously, the MF impeded pore blockage in HZSM-5 and kept acidic sites from deactivating due to carbon deposition. This study lays a crucial groundwork for improving advanced technologies aimed at optimizing the utilization of organic solid waste. [ABSTRACT FROM AUTHOR]

Black soldier fly farming is gaining traction globally as a strategy for recycling organic waste into high-quality proteins and fat for feed and organic fertilizer for crop production. The support of governments in East Africa to integrate insect meal in livestock feed has opened opportunities for commercializing insect products. Understanding the potential value of Black soldier fly larvae meal (BSFLM) is paramount to inform policies and practices to promote insect farming and insect-based feed for livestock production. This paper uses the economic surplus method to generate evidence on the potential socioeconomic impact of replacing conventional soybean and fish meal protein sources with insect-based feed (IBF), BSFLM, in Uganda. Results indicate that substitution of IBF for existing protein sources will generate net economic benefits of USD 0.73 billion in 20 years (0.037 billion per year). The benefit-cost ratio is estimated at 28:1, and the internal rate of return is 138%, indicating that the insect-based animal feed industry is a profitable investment. Even in the worst-case scenario, when the replacement rate of IBF and its economic benefits are reduced by half, the benefit-cost ratio remains high (8:1). The estimated economic benefit can lift about 4.53 million people above the poverty line in the country. It can also create about 1,252-563,302 new jobs per annum, depending on the substitution rate of conventional protein feeds with IBF (0.1%-45%). Uganda has the potential to produce from about 3,244 tons to 1.5 million tons of IBF. Similarly, using the same replacement rates, the country can produce about 695-312,678 tons of NPK fertilizer from biowaste recycling. About 0.09-41 million tons of biowaste could be recycled, depending on the replacement rate of conventional feed sources with IBF. Our results justify that investing in the insect feed value chain can contribute to Uganda's economic, social, and environmental sustainability. [ABSTRACT FROM AUTHOR]

[Display omitted] • HCSOF exhibits high levels of organic carbon and nutrient content. • HCSOF exhibits favorable adsorption properties. • HCSOF holds promise as a substitute for conventional chemical fertilizers. • HCSOF serves to enhance growth and bolster disease resistance of corn. Traditional methods of producing organic fertilizers result in significant nutrient loss and greenhouse gas emissions, making it challenging to align with sustainable development and the achievement of net-zero emissions goals. Hydrothermal cracking, as a novel clean technology for the utilization of organic waste into fertilizer, has been extensively studied and refined in laboratory settings, but its large-scale industrial evaluation remains limited. This study investigates the properties and field application of hydrothermal cracking solid organic fertilizer (HCSOF) produced at a pilot scale with an annual output of 10,000 tons. The results indicate that the organic matter content and total nutrient content (TN + P 2 O 5 + K 2 O) of HCSOF reached 50.6 % and 5.46 %, respectively, which are 20.6 % and 1.46 % higher than the standards for organic fertilizers in China. Additionally, contaminants such as pathogens and antibiotics in the product were completely eliminated. Elemental analysis and pore size distribution highlighted the unique adsorptive attributes of HCSOF, which showed significant effect in reducing soil ammonium nitrogen. Results from field trials indicate that the complete substitution of chemical fertilizers with HCSOF did not reduce corn yield, which remained at 9.03 t/ha. Particularly, compared to the exclusive use of chemical fertilizers, HCSOF treatments resulted in a 7.03 % and 4.70 % decrease in fresh corn lodging and disease incidence, respectively. Antibacterial tests further confirmed its ability to counter pathogens. This study provides robust evidence for scaling up hydrothermal cracking fertilizer production from laboratory to industrial levels. Future research should focus on multi-batch sampling and extended field experiments. [ABSTRACT FROM AUTHOR]

Alternative farming systems have developed since the beginning of industrial agriculture. Organic, biodynamic, conservation farming, agroecology and permaculture, all share a grounding in ecological concepts and a belief that farmers should work with nature rather than damage it. As ecology-based agricultures rely greatly on soil organisms to perform the functions necessary for agricultural production, it is thus important to evaluate the performance of these systems through the lens of soil organisms, especially soil microbes. They provide numerous services to plants, including growth promotion, nutrient supply, tolerance to environmental stresses and protection against pathogens. An overwhelming majority of studies confirm that ecology-based agricultures are beneficial for soil microorganisms. However, three practices were identified as posing potential ecotoxicological risks: the recycling of organic waste products, plastic mulching, and pest and disease management with biopesticides. The first two because they can be a source of contaminants; the third because of potential impacts on non-target microorganisms. Consequently, developing strategies to allow a safe recycling of the increasingly growing organic matter stocks produced in cities and factories, and the assessment of the ecotoxicological impact of biopesticides on non-target soil microorganisms, represent two challenges that ecology-based agricultural systems will have to face in the future. [ABSTRACT FROM AUTHOR]

Organic wastes (OW) are rich in nutrients, and their recycling into agriculture can substitute chemical fertilizers. The level of substitution (partial with mineral fertilizer or exclusive with only OW), along with the method, amount, and timing of OW application, as well as the crop type, can impact crop productivity. The temporal dynamics of crop productivity after repeated applications of OW remain uncertain. Thus, two French long‐term field experiments (QualiAgro and PROspective, started in 1998 and 2000, respectively) were used to evaluate the effect of repeated OW applications on crop yield dynamics and investigate the potential driving factors affecting crop yields. Six different OW were applied: urban sewage sludge (SLU), green waste and SLU compost (GWS), biowaste compost (BIO), municipal solid waste compost (MSW), farmyard manure (FYM), and composted FYM (FYMC). The OW were applied every 2 years in QualiAgro (~4 t C ha−1) and PROspective (~1.7 t C ha−1). QualiAgro was studied under high and low mineral N conditions, while PROspective was examined with and without mineral N fertilization. The results indicated that at the QualiAgro site, a combination of OW and high mineral N treatments resulted in higher maize and wheat yields compared to the mineral N control, while the combination of OW and low mineral N reached the same maize and wheat yield as the mineral N control after 3 and 6 applications of OW, respectively. At the PROspective site, partially substituting mineral fertilizer with OW maintained maize yields but decreased wheat yields, while full substitution led to a decrease in both maize and wheat yields compared to the mineral N control. Results from the gradient boosting model (GBM) showed that soil total N rather than mineral N input was the primary driver of the relative maize yield, while mineral N fertilizer input was more critical for wheat during the second year. We conclude that the joined use of OW and mineral fertilizers is superior to using OW or mineral fertilizer alone for maintaining high yields and soil fertility. We further suggest that OW full substitution of mineral fertilizer may need to apply OW more frequently to meet the crop demands, and/or to use OW with higher N availability like digestates. [ABSTRACT FROM AUTHOR]

The use of agricultural chemicals has adversely affected soil health and the environment. Organic farming practices, particularly vermicompost (VC), are gaining attention for their potential to improve soil fertility and crop productivity. This study investigated VC rate applications on lettuce growth, yield, soil fertility, nutrient dynamics, enzyme activity, biological parameters, and biochemical aspects under greenhouse conditions in Samsun, Turkey during 2022–2023. Experimentally, VC was applied at rates of V1: 1%, V2: 2%, and V3: 4% w/w, with a control group without VC application, V0: 0% w/w. Batavia lettuce, which is sensitive to environmental conditions and nutrient deficiency, was subjected to these treatments in a randomized complete block design, replicated thrice. Results showed consistent improvements in plant dry weight across all VC treatments, with the 2% application rate (V2) yielding the highest increase in lettuce yield (56.43%). Soil pH varied across treatments, with V1 being slightly alkaline and V3 showing high electrical conductivity and increased nitrogen content. Phosphorus content increased in all treatments, while potassium varied, with V3 having the highest values. Soil enzyme activities increased with VC concentrations, with V3 showing the highest urease activity. Pearson correlations confirmed positive associations with growth parameters and soil enzymatic activity. These findings highlight vermicompost as a sustainable solution for lettuce production and soil improvement. [ABSTRACT FROM AUTHOR]

Purpose: The growing adverse effects of agrochemicals on environmental health and safety warrant an examination of ecologically safe alternatives for weed control. The objective of this study was to determine the effect of rice-husk waste on the growth performance and weed management (WM) of Ocimum sanctum. Method: In a randomized complete block design with three replications, nine weed management (WM) methods were assessed. These methods included black, red, and transparent polyethylene mulches; rice-husk; sawdust; hoe-weeding at 30 days after transplanting (DAT); a one-time application of 0.2 kg/ha Haloxyfop-P at 30 DAT; daily weeding; and no-weeding. Data were collected on weed parameters and growth attributes of Ocimum sanctum. All data were subjected to analysis of variance. Results: The use of rice-husk mulch resulted in the most significant (pDaily-weeding>Hoe-weeded>Rice-husk>Haloxyfop-PEHS>Red-polyethylene>Sawdust> Transparent-polyethylene>Control in WCE at 10 WAT. Conclusion: The study revealed that rice-husk mulch was the most effective in enhancing the growth and yield attributes of Ocimum sanctum, ranking fourth in weed control efficiency (WCE) at 72.60%, following black polyethylene (BP) mulch (100%), daily-weeding (96%) and hoe-weeded (95.7%). Highlights · The study revealed that black polyethylene mulch exhibited the highest weed control efficiency exceeding 90%, and recorded complete weed suppression (11%) at 10 weeks after application. · Higher weed species diversity was observed in plots subjected to hoe-weeded, rice husk mulched, and post-emergence herbicide treatments, suggesting that weed management techniques can influence the composition of weed flora. · Mulching with rice-husk significantly improved several growth parameters of Ocimum sanctum, including leaf number, number of branches, plant height, stem girth, canopy diameter, and leaf yield,when compared to other weed control methods. · Organic waste recycling practices such as use of rice-husk as mulch offer an effective, sustainable, eco-friendly, and cost-effective option for weed management in crop fields. · Medicinal herbs like Ocimum sanctum can be cultivated effectively using rice-husk mulch which provides advantages such as soil moisture retention, weed suppression, and improved growth performance.

Background and Aim: Hermetia illucens, a black soldier fly, is widely recognized for sustainable recycling of organic waste. Black soldier fly larvae (BSFLs) can consume various types of biowastes and convert them into nutrient-rich biomass, including proteins, lipids, chitin, and minerals. This study investigated the best extraction method by comparing the fatty acid profiles, percentage yield, and antioxidant properties of BSFL oil extracted using different extraction methods. Materials and Methods: The physicochemical properties, fatty acid profile, and free radical scavenging ability of BSFL oil were analyzed using six extraction methods. Results: Ultrasonic extraction with hexane resulted in the highest yields compared with different extraction methods. Lauric acid (28%-37%) was the most abundant fatty acid in all extracts, followed by palmitic acid, myristic acid, oleic acid, and linoleic acid. Compared with other methods, aqueous extraction showed the highest lauric acid composition and free radical scavenging activities. In addition, high-temperature aqueous extraction resulted in higher oil yield and free radical scavenging activities than low-temperature extraction. Conclusion: High-temperature aqueous extraction is the best extraction method because it is rich in lauric acid, has antioxidant ability, and can be further developed to produce novel sustainable biomaterials for humans and animals. [ABSTRACT FROM AUTHOR]

effective use of municipal organic waste (MOW) derived composts for soil nutrient management is crucial for sustainable crop production and environmental protection. Maize cultivation using MOW compost is economical and environmentally beneficial around the world. Adding MOW compost to the soil improves maize yield. A field study was conducted in 2022 and 2023 to determine the effects of two composts made from MOW mixed with Vermiculite, Cow dung, and NPK fertilizer at three levels (5, 10, and 15 ton/ha) on maize yield and yield components. Three replications split plot statistical design. Main plots had compost levels, while subplots had four MOW waste composts: MOW, Vermiculite + MOW, Cow manure +MOW, and 125 kg/ha NPK fertilizer with MOW. Each 6 m2 plot had a 50 cm line-to-line and 30 cm plant-to-plant distance. MOW compost with NPK fertilizer had the greatest impact on yield and yield-related characteristics, followed by Vermiculite and Cow manure compost at 15 ton/ha. Finally, MOW mixes with NPK at 15 ton/ha performed best for all maize characteristics. This qualitative and quantitative analysis will not only shed fresh light on converting MOW to compost in the context of arid land agriculture but will also pave the way for a substantial and worthwhile expansion of maize production. [ABSTRACT FROM AUTHOR]

Purpose: Solid organic waste is a major environmental issue in various parts of the world. Proper management techniques for disposing of such wastes can reduce health issues as well as contamination of the environment. Modern scientific techniques in conjugation with traditional practices can manage biowaste in an efficient, economical, and sustainable manner. This present review highlights the possibilities of utilizing biowastes from various sources for the enhancement of soil fertility, residue management, crop growth and higher yields. Methodology: The article is prepared from secondary materials i.e. research and review articles published in different journals. The review of literature from these articles in terms of soil quality, salinity, impact of salinity on crop production and possibilities to reclamate saline soil to improve productivity of soil were systematically carried out. A summary of the present work was developed using the following approach. Result: Various management practices, in-situ and ex-situ techniques help reduce biowastes and transform them into useful nutrients that could be applied to soil for alleviating the nutritional deficiency in saline/sodic soil. Composting using microbes and earthworms has been traditionally practiced for reducing/converting waste into compost and applying them to agricultural fields to improve soil fertility and crop productivity. Conclusion: Using waste management techniques and converting biowaste into manure for enhancing agricultural productivity provides sustainable agriculture practices in addition to pollution reduction. [ABSTRACT FROM AUTHOR]

Climate change and its impacts on agriculture are relatively well documented at the global and regional levels, while adaptation measures to sustain food production are mostly location specific. Such measures integrated into a production system as a farming practice will become robust based on its performance at smallholder farms. Therefore, a long-term (2011-2018) study was undertaken to evaluate these practices in a crop-livestock integrated farming system (IFS) approach as a climate-smart agricultural (CSA) strategy for enhancing agricultural production on a humid tropical island. The results showed a significant increase in on-farm productivity from 2.8 t ha-1 in 2011-35.6 t ha-1 in 2018 and net returns from USD 359 to more than 3500 ha-1 due to the adoption of CSA practices. Most importantly the study found increase in the sustainability index (0.89) by the adoption of CSA practices such as crop and enterprise diversification and land manipulation. The climate smartness of these practices was witnessed in reduced greenhouse gas (GHG) emissions and expanded carbon sink that resulted in a mitigation benefit of 5.40 Mg CO2eq ha-1yr-1. CSA practices such as crop diversification through raised beds, enterprise diversification, crop rotation, green manuring, in-situ rainwater harvesting, and contingency cropping significantly contributed to enhancing the production of crop-livestock IFS. Crop residue mulching, agro-forestry and organic waste recycling contributed for enlarging the C sink and minimizing net GHG emissions. Based on these findings, we demonstrated that a crop-livestock IFS was the best climate-smart strategy to enhance the productivity and food security of smallholder farmers in a sustainable way against the consequences of climate change and to increase the mitigating potential through carbon stocking. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Sciences, Belgrade is the property of University of Belgrade, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The disposal of high volumes of organic waste is a global issue. Using organic waste instead of sand as an aggregate material for concrete could reduce the strain on waste treatment processes and on the extraction of finite resources. At the same time, it could be a climate change mitigation strategy, by storing the biogenic carbon contained in the organic waste. This project investigated the viability of replacing 10% of fine aggregate in concrete with various organic waste materials, namely rice husk ash, wood ash, corncob granules, and wheat straw. The fresh concrete's properties were studied using the slump test, and the hardened concrete's mechanical properties were measured using the compressive strength and flexural strength tests. In this study, 14 days of curing were considered for the mechanical tests, although the 28-day mechanical strength is more generally accepted. The mechanical performances along with a life cycle assessment (LCA) comparison between the concrete with organic waste and traditional concrete were conducted. The results suggested that rice husk ash and wood ash are the most-suitable organic waste products for use as aggregate replacers considering the mechanical properties. The concrete samples incorporating wheat straw and corncob granules exhibited relatively low strength; unless advanced treatment methods are applied to enhance the concrete's performance, the utilization of these organic wastes in concrete may be limited. The environmental impact assessment of traditional concrete shows that the main contributor to almost every impact category is the production of Portland cement. Sand production contributes only marginally to the overall impact of the concrete. In terms of life-cycle greenhouse gas (GHG) emissions, traditional concrete exhibits the lowest GWP impact per cubic meter when mechanical properties are included in the functional unit used for the comparison. Nevertheless, concrete samples with wood ash and rice husk ash partially offset their lower compressive strength with higher carbon sequestration, showing a similar GWP impact to traditional concrete. This makes them promising alternatives, especially for cases where limited compressive strengths are needed. Further investigations to improve their mechanical properties and optimize their performance are warranted. [ABSTRACT FROM AUTHOR]

The utilization of agricultural waste organic materials through composting technology has gained significant traction in agricultural production as an effective means of crop nutrient management. However, the differences in the impact of organic amendments prepared by traditional composting and vermicomposting on soil properties still deserve further research. Based on field experiments conducted in greenhouse, compared to chemical fertilizer treatments as control, we utilized traditional compost (OF) and vermicompost (VcF) derived from agricultural organic waste edible mushroom bran and cow manure (2:8). Variations in soil physiochemical properties, activities of soil enzymes related C and P cycling, abundances and diversities of bacterial 16S rRNA and fungal ITS gene at total DNA level were analyzed. Both compost treatments enhanced soil organic carbon, soil total phosphorus, and soil available P content significantly and also increased the activities of soil α‐glucosidase, β‐glucosidase, acid phosphomonoesterase, and alkaline phosphomonoesterase significantly. The above results suggested that soil C and P transformations were stimulated effectively by both organic amendments. OF and VcF increased the fungal ITS absolute abundances significantly while diversity indices of soil bacterial community increased significantly under both treatments. Correlation analysis indicated that bacterial community composition was strongly correlated with several soil property indexes while fungal community composition was only significantly correlated with soil total phosphorous content. In conclusion, similar to traditional compost, vermicompost significantly improved soil nutrient cycling (especially C and P aspects). In terms of soil microbes, bacteria and fungi showed different responding mechanism to vermicompost: bacteria adjust microbial structure, while fungi tend to proliferated. In consideration of the advantages of vermicompost in technology and economic cost, it could be applied in the subsequent agricultural production more frequently. [ABSTRACT FROM AUTHOR]

This study is being conducted to find out how to treat waste food by Hermetia illucens (L.). The impact of several diets on the life cycleand size of different development stages of this species was studied. H. illucens lays its eggs in heaps in nesting boxes, with an egg incubation period of 03 ± 0.9 days and a larval phase of 24.21 ± 4.10 days.The prepupa stage lasts approximately 03 days, and the transformation of larvae into pupae begins on the 16th day and lasts until the 41st day after the egg incubation. The sex ratio is 49,34 ±7.62% for females and 50.41± 7.74% for males.H. illucens larvae have an average weight of 0.13 ± 0.03 g, a length of 1.66 ± 0.14 cm, and a width of 0.46 ± 0.05 cm. Pre-pupa weigh 0.17 ± 0.06 g, pupa measures 02.05 ± 0.13 cm in length and 0.52± 0.04 cm in width, and adult weighs 0.03 ± 0.01 g. A hundred eggs weigh 0.0085 g, and the shell of the egg represents 63.42% of the egg.The black soldier fly larva consumes 0.36 to 0.47 g of food during its development, with an average value of food utilization of 75.57 ± 8.53%. At the end of the larval phase, the larvae reached a maximum size of 1.8 cm. The lipids and proteins contained in cheese and quail eggs improved the weight of larvae, resulting in a gain of 0.04 g/larva.H. illucens was bred on mud from a wastewater treatment unit with an average weight of 0.25 g, length of 2.12 cm, and width of 0.58 cm. The findings of this study indicate that food waste in Algeria can be utilized by black soldier fly larvae, resulting in a shorter development period and increased larval biomass. [ABSTRACT FROM AUTHOR]

Zoo waste is a common problem in urban areas, as it overloads municipalities. To enhance the park's appeal, sustainability, and cleanliness, a pilot vermicomposting process was implemented as an alternative for organic waste disposal. It aimed to address the negative effects of poor organic waste management. Three types of pond water, namely hippopotamus, crocodile, and gharial, were recycled. Additionally, ostrich droppings and the nitrogenous compounds abundant in carnivore feces were utilized. The study sought to improve organic waste management and recycle pond water using exotic worms. Chemical and physical analyses were conducted on pond water and vermicompost obtained from Gandhi Zoological Park, revealing their high nutrient content. Fourier transform infrared spectroscopy was employed to study the functional groups present in the compost and vermicompost, allowing the detection of vermicompost maturity. The biomass of exotic earthworms, as well as the count of cocoons, juveniles, and adults, was assessed during different seasons of the year. This approach facilitated the recycling of pond water and the reduction of organic waste within the zoo premises. It involved the symbiotic cooperation of earthworms and bacterial colonies, transforming the waste into a high‐quality product with balanced macro nutrients. The novelty of the study lies in its focus on nutrient recycling in pond water, ostrich droppings, and vermicomposting of organic waste from carnivores. [ABSTRACT FROM AUTHOR]

Featured Application: The featured application of this paper focuses on the impact of climate change on ecosystem services provided by the Phyllognathus excavatus beetle, specifically its role in recycling organic matter. The study highlights that dung beetles, including Phyllognathus excavatus, play a crucial ecological role in nutrient cycling, waste decomposition, and soil improvement. These beetles facilitate the breakdown of organic matter, such as dung, and contribute to the recycling of nutrients back into the ecosystem. However, climate change can disrupt the life cycles and habitat suitability of these beetles, affecting their ability to perform their recycling function effectively. Changes in temperature and precipitation patterns can alter the availability of fresh dung, which is essential for successful reproduction and larval development. Shifts in rainfall patterns and increased temperatures can also impact the timing of dung decomposition and alter the composition of microbial communities associated with dung, indirectly affecting the survival and fitness of dung beetles. Determining the resilience of ecosystem services, such as recycling, and creating effective conservation strategies to mitigate the negative effects of climate change on these significant ecological processes depend on our ability to understand the potential effects of climate change on Phyllognathus excavatus and other dung beetles. Climate change poses a significant threat to ecosystems, food security, and human well-being. This study focuses on the Phyllognathus excavatus beetle, an important insect species in the Mediterranean region with ecological importance in nature recycling of organic wastes. The aim of this study is to assess its current habitat suitability and predict its distribution under future climate scenarios. The beetle's occurrence records were gathered and climate information, including 19 bioclimatic variables, was retrieved from the Global Biodiversity Informatic Facility (GBIF) and WorldClim depository, respectively. The MaxEnt algorithm was used to calculate habitat appropriateness using geographic information systems (GISs) and species distribution modeling (SDM) with an accuracy of 0.907 using the AUC test. The findings show that the annual mean temperature is the most important factor, with the beetle flourishing in temperatures between 13.9 and 19.1 °C. The distribution is greatly impacted by the mean temperature of the warmest quarter. Future projections using different climate scenarios suggest potential changes in the beetle's distribution. By integrating climate data and occurrence records, this study provides insights into the vulnerability of Phyllognathus excavatus to climate change and identifies regions where its habitat may be at risk as 81% of its current habitat will be lost. The research helps to prioritize efforts to reduce the harmful effects of climate change on insect biodiversity and to design effective conservation strategies. Overall, this study advances our knowledge of the Phyllognathus excavatus beetle's present and projected distribution patterns in the Mediterranean region under the influence of climate change. It illustrates the significance of taking into account how climate change would affect insect populations and the use of SDM and GIS tools for researching and protecting insect biodiversity. [ABSTRACT FROM AUTHOR]

• Life cycle assessment (LCA) is a powerful tool to determine composting environmental impacts. • Greenhouse gas emissions from composting must be carefully evaluated in any LCA composting study. • The need of consistent input data is one of the main challenges for the assessment. • The avoided impacts derived from compost application should also be considered. • The selected functional unit in LCA composting studies is critical for the results obtained. Composting is one of the most widely applied methods for recycling organic waste. This process has been proposed as one option that facilitates the reincorporation of materials into the production cycle. However, composting also generates environmental impacts. Life Cycle Assessment (LCA) is the most common approach to evaluate the environmental impacts of a process at different system stages. Nevertheless, applying LCA in composting facilities is challenging due to the extensive information required, the lack of standardization on the initial assumptions, the definition of system boundaries, and the high diversity of existing composting technologies. This paper systematically reviews LCA studies in biowaste and/or green waste composting. The study highlights the challenges that should be met in order to improving the application of LCA to evaluate the environmental impacts of this type or waste treatment strategy. The review protocol used identified 456 papers published between 2010 and 2022. After the screening, 56 papers were selected, read, and thoroughly analyzed. The results show that: i) about 68% of the studies aimed to compare composting with other solid waste management options; ii) there was a wide diversity among the impact categories considered, which predominantly included climate change and ozone depletion; iii) there was no consensus on the functional unit or the system boundaries; iv) the main gaseous emissions studied were ammonia, methane, and nitrogen oxide, which were generally determined by emission factors; v) the avoided environmental impacts associated with the end-product quality and its application as an organic amendment or soil improver were ignored. This work demonstrates the complexity of conducting credible and valid composting LCA studies and proposes seven recommendations for improving the application of this assessment methodology to analyze this waste management alternative. [ABSTRACT FROM AUTHOR]

There is much organic waste that comes from by-products of agriculture and product processing, solid waste from livestock, and municipal waste. Conventional methods that are widely used for the treatment and management of organic fractions of waste are landfilling, composting, anaerobic digestion, incineration, gasification, and pyrolysis. Among the above methods, pyrolysis is a relatively simple, robust, and scalable technology for transforming diverse organic waste feedstock into renewable energy products. Recently, the electrochemical conversion of biochar into electricity in direct carbon fuel cells (DCFC) has also been investigated and shown to be feasible and highly efficient. This paper focuses on the utilization of organic waste as a fuel and the investigation of their characteristics during electrochemical reactions in molten hydroxide direct carbon fuel cells (MH-DCFCs). Organic waste of different origins (the food-processing industry, urban and suburban areas, municipal solid organic waste, sewage sludge) with diversified characteristics was used as the main feedstock. The lowest power density was determined for sewage sludge (5.1 mW cm−2), and the best results were obtained for peanut shells (53.14 mW cm−2). This study concludes that higher elemental carbon, lower ash content and the presence of reactive surface oxygen functional groups in biochar obtained from organic waste might contribute to better cell performance. Moreover, the research establishes the potential of carbonized organic waste as a prospective alternative fuel source for power generation in an MH-DCFC. [ABSTRACT FROM AUTHOR]

Recycling of organic wastes for agricultural production has been recommended as a sustainable way to close the phosphorus (P) cycle. This study seeks to characterize the P forms in organic fertilizers derived from agricultural and nonagricultural source materials to understand how these organic fertilizers will affect corn growth and soil available P. Organic fertilizers including turkey litter compost (TLC), biosolid pellets (BSP), and source separated organic compost (SSO) were applied to a sandy loam soil and compared to controls that received no nutrients or chemical fertilizer. Results from sequential chemical extractions and X‐ray absorption near edge structure spectroscopy revealed that most of the P species are inorganic, with SSO and TLC containing primarily Ca‐P and Mg‐P forms, while the P in the BSP treatments was mostly associated with aluminium (Al). The two chemical fertilizer treatments had the greatest impact on corn height at the initial growth stage; however, after 42 days, corn height was similar for the organic fertilizers and chemical treatment. This initial slow response from the organic fertilizer treatments reduced the grain yield compared to chemical treatment. The results of this study suggest that priority should be given to sufficient P availability at the initial growth stage. Overall, organic fertilizer is a promising P source for grain crop production, but calibration and correlation studies are needed to ensure optimum supply of P for the initial growth stage. Core Ideas: Phosphorus forms in the organic fertilizer used in this study were highly variable.Early corn response to organic fertilizer is slower than chemical fertilizer applied at the same total P rate.Turkey litter compost shows the greatest potential as a P source for grain crop production.Increasing the rate of P application reduced the P use efficiency. [ABSTRACT FROM AUTHOR]

Technological advancement in recent decades has allowed for crop cultivation in soilless controlled environments, known as hydroponics, and this is being employed in an increasing number of factories worldwide. With continued local and regional disruptions in the supply chain to provide mineral fertilizers, new pathways to generate nutrient solutions are being developed. One potential approach is the recovery of nutrients from organic waste and wastewater using bioponics. Bioponics refers to the biological mineralization of organic residues through processes such as anaerobic and aerobic digestion and the use of such organically produced nutrient solutions in hydroponic systems. However, without disinfection of the nutrient solution, the high microbial loads increase the risk of pathogens affecting plant and consumer health. In this work, electrochemical hydrogen peroxide (H2O2) demonstrated success in reducing microbial loads. Different scenarios of application were considered: (1) variation in the H2O2 concentration in the nutrient solution by dosing H2O2 from ex situ electrochemical production, (2) variation in the dosing time-dependent reaction between the nutrient solution and H2O2 produced ex situ, and (3) the in situ production of H2O2 of the organic nutrient solution. The highest tested H2O2 concentration of 200 mg L−1 showed a microbial load reduction of bacteria at 93.3% and of fungi at 81.2%. However, the in situ production showed the highest reduction rate for bacteria and fungi in bioponic nutrient solutions, where longer reaction times also impact microbial concentrations in situ. Final microbial reductions of 97.8% for bacteria and of 99.1% for fungi were determined after a H2O2 production time of 60 min. Overall, our results show that electrochemical H2O2 production can be used to disinfect bioponic nutrient solutions, and the production cell can be implemented in bioponic systems in situ. [ABSTRACT FROM AUTHOR]

This document is a special issue of the journal Processes focused on "Biomass Conversion and Organic Waste Utilization." It highlights the importance of recycling and utilizing biomass and organic wastes as strategies for saving energy and resources. The issue includes research on various techniques and processes for the disposal and reutilization of biomass wastes, such as thermal conversion, adsorption, biofuel production, simulation studies, and composting. The papers presented in this issue aim to advance waste management and the circular economy by addressing the complex composition and volatile properties of biomass wastes. [Extracted from the article]

Technologies used in municipal wastewater treatment plants (WWTPs) allow the recovery of energy and valuable elements (phosphorus, nitrogen, and organic carbon) for the soil. This article presents, in schematic form, the carbon, nitrogen, and phosphorus cycling in a WWTP with a load of 70,000 Population Equivalent and develops a spreadsheet to estimate their recovery. Biogas generation enables the recovery of 1126 Mg of organic carbon per year and the generation of 12.6 GWh of energy. The most rational form of organic waste recycling is the production of compost with fertilizing parameters, but efforts should be made to reduce iron compounds in its composition. It has been estimated that compost production provides the recovery of 30% of carbon, 98% of phosphorus, and 18% of nitrogen from the streams of these elements entering the WWTP. The possibility of partially replacing the iron coagulants used to precipitate phosphorus with waste magnesium salt is presented, leading to the precipitation of struvite, which is well absorbed by plants. The article presents the advantages of combining sewage treatment with organic waste management in WWTPs. The developed spreadsheet allows for the control of energy recovery through the quantitative selection of organic waste for fermentation. [ABSTRACT FROM AUTHOR]

Biomass gasification has obtained great interest over the last few decades as an effective and trustable technology to produce energy and fuels with net-zero carbon emissions. Moreover, using biomass waste as feedstock enables the recycling of organic wastes and contributing to circular economy goals, thus reducing the environmental impacts of waste management. Even though many studies have already been carried out, this kind of process must still be investigated and optimized, with the final aim of developing industrial plants for different applications, from hydrogen production to net-negative emission strategies. Modeling and development of process simulations became an important tool to investigate the chemical and physical behavior of plants, allowing raw optimization of the process and defining heat and material balances of plants, as well as defining optimal geometrical parameters with cost- and time-effective approaches. The present review paper focuses on the main literature models developed until now to describe the biomass gasification process, and in particular on kinetic models, thermodynamic models, and computational fluid dynamic models. The aim of this study is to point out the strengths and the weakness of those models, comparing them and indicating in which situation it is better to use one approach instead of another. Moreover, theoretical shortcut models and software simulations not explicitly addressed by prior reviews are taken into account. For researchers and designers, this review provides a detailed methodology characterization as a guide to develop innovative studies or projects. [ABSTRACT FROM AUTHOR]

Organic waste-derived solar cells (OWSC) are a classification of third-generation photovoltaic cells in which one or more constituents are fabricated from organic waste material. They are an inspirational complement to the conventional third-generation solar cell with the potential of revolutionizing our future approach to solar cell manufacture. This article provides a study and summary of solar cells that fall under the category of OWSC. OWSC own their merit to low cost of manufacturing and environmental friendliness. This review article reveals different organic waste raw materials, preparation-to-assembly methodologies, and novel approaches to solar cell manufacturing. Ideas for the optimization of the performance of OWSC are presented. The assembly configurations and photovoltaic parameters of reported OWSC are compared in detail. An overview of the trends in the research regarding OWSC in the past decade is given. Also, the advantages and disadvantages of the different solar cell technologies are discussed, and possible trends are proposed. Industrial organic waste raw materials such as paper, coal, and plastics are among the least explored and yet most attractive for solar cell fabrication. The power conversion efficiencies for the cited works are mentioned while emphasizing the products and functions of the organic waste raw materials used. [ABSTRACT FROM AUTHOR]

Purpose: This study analyzed the ability of Black Soldier Flies Larvae (BSFL) in reducing grease waste and the effect of variation in feed composition on the growth rate effect of larvae age at 8 days, 12 days, and 16 days. Method: Before reaching the specified age (8, 12, or 16 days), the larvae are fed a mixture of expired bread and expired milk. BSFL at ages 8 days, 12 days, and 16 days are fed by pure grease waste or the mixing of grease waste and expired milk until turned into 20-day-old larvae. Then waste reduction is analyzed based on parameters such as feed consumption, waste reduction index, the efficiency of conversion of digested feed, and larvae biomass. Univariate analysis using SPSS was conducted to determine the significance of differences in waste reduction, feed consumption, conversion efficiency of digested feed, and larvae biomass among the experimental groups. Results: The 16-day-old larvae fed with pure grease waste achieved a waste reduction index of 20.08 grams per day. Moreover, variations in feed composition influenced the growth rate of BSFL, with larvae fed a mixture of grease waste and expired milk exhibiting the largest weight (43 mg) and length (1.4 cm) among the 16-day-old larvae. Conclusion: Black Soldier Fly Larvae at 16 days old displayed remarkable effectiveness in reducing grease waste from restaurants. This study underscores the potential of BSFL as a sustainable waste management and recycling solution for organic waste, particularly in the context of food waste. [ABSTRACT FROM AUTHOR]

Recent EU circular economy, bioeconomy policies and the New Green Deal promote the recycling of organic wastes into soil improvers and fertilisers, thereby reducing the use of mineral fertilisers. This has renewed interest in the use of compost and digestate as fertilisers. At the same time, the Russian invasion of Ukraine has strengthened the demand for sustainable domestic fertilisers to guarantee the security of supply. It is now more important than ever that quality standards in Ireland are fit for the purpose of aiding the sustainable local production of fertilisers. Quality standards for compost and digestate ensure and protect the environment. This study collated the results of the analysis of Irish compost and digestate samples and made comparisons of the Irish data to databases, reports and standards from other countries, including the EU Fertiliser Products Regulation 2019/1009. This paper, therefore, provides comprehensive information on heavy metal, stability and phytotoxicity standards from a number of European and other countries. In addition, it includes actual data on these parameters from Ireland and a few European countries. From this collation and comparison process, we propose to update the heavy metals and stability limits in the Irish compost standard (IS 441) and heavy metals and stability limits in a new digestate standard (whole, liquid and fibre). Our methodology and collated data can be used as templates for countries, especially in Europe, which have not developed their own standards. Having an updated compost quality standard supports the development of a circular economy while still respecting the precautionary principle of avoiding pollution when compost and digestate are used on the soil. [ABSTRACT FROM AUTHOR]