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• The elevated HTC temperature reduced the DOM release from hydrochars. • Three fluorescent components were identified in hydrochar DOM by EEM-PARAFAC. • Feedstock type and HTC temperature significantly affected the DOM characteristics. • The elevated HTC temperature reduced the germination index value of hydrochar DOM. The dissolved organic matter (DOM) with high mobility and reactivity plays a crucial role in soil. In this study, the characteristics and phytotoxicity of DOM released from the hydrochars prepared from different feedstocks (cow manure, corn stalk and Myriophyllum aquaticum) under three hydrothermal carbonization (HTC) temperatures (180, 200 and 220°C) were evaluated. The results showed that the hydrochars had high dissolved organic carbon content (20.15 to 37.65 mg/g) and its content showed a gradual reduction as HTC temperature increased. Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances (C1, 30.92%-58.32%), UVA humic acid-like substance (C2, 25.27%-29.94%) and protein-like substance (C3, 11.74%-41.92%) were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis. High HTC temperature increased the relative proportion of aromatic substances (C1+C2) and humification degree of hydrochar DOM from cow manure, while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum. aquaticum. The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM. Additionally, seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43% in contrast with control, and the germination index values were 73.57%-91.12%. These findings provided new insights into the potential environmental effects for hydrochar application in soil. [Display omitted] [ABSTRACT FROM AUTHOR]

• Antibiotics (OTC, CIP) reduced manure carbon, nitrogen, phosphorus release rate. • OTC and CIP greatly altered microbial community structure during decomposition. • OTC and CIP decreased G-bacterial abundance and activity of digestive enzymes. • CIP had greater impact on microbial community structure than OTC. • G+ bacteria in cattle manure were OTC-tetracycline-resistant. The land application of livestock manure has been widely acknowledged as a beneficial approach for nutrient recycling and environmental protection. However, the impact of residual antibiotics, a common contaminant of manure, on the degradation of organic compounds and nutrient release in Eutric Regosol is not well understood. Here, we studied, how oxytetracycline (OTC) and ciprofloxacin (CIP) affect the decomposition, microbial community structure, extracellular enzyme activities and nutrient release from cattle and pig manure using litterbag incubation experiments. Results showed that OTC and CIP greatly inhibited livestock manure decomposition, causing a decreased rate of carbon (28%–87%), nitrogen (15%–44%) and phosphorus (26%–43%) release. The relative abundance of gram-negative (G-) bacteria was reduced by 4.0%–13% while fungi increased by 7.0%–71% during a 28-day incubation period. Co-occurrence network analysis showed that antibiotic exposure disrupted microbial interactions, particularly among G- bacteria, G+ bacteria, and actinomycetes. These changes in microbial community structure and function resulted in decreased activity of urease, β-1,4-N-acetyl-glucosaminidase, alkaline protease, chitinase, and catalase, causing reduced decomposition and nutrient release in cattle and pig manures. These findings advance our understanding of decomposition and nutrient recycling from manure-contaminated antibiotics, which will help facilitate sustainable agricultural production and soil carbon sequestration. [Display omitted] [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. An increasing number of countries are investigating options to stop the spread of the emerging zoonotic infection Salmonella Dublin (S. Dublin), which mainly spreads among bovines and with cattle manure. Detailed surveillance and cattle movement data from an 11-yr period in Denmark provided an opportunity to gain new knowledge for mitigation options through a combined social network and simulation modeling approach. The analysis revealed similar network trends for noninfected and infected cattle farms despite stringent cattle movement restrictions imposed on infected farms in the national control program. The strongest predictive factor for farms becoming infected was their cattle movement activities in the previous month, with twice the effect of local transmission. The simulation model indicated an endemic S. Dublin occurrence, with peaks in outbreak probabilities and sizes around observed cattle movement activities. Therefore, pre- and postmovement measures within a 1-mo time window may help reduce S. Dublin spread. [ABSTRACT FROM AUTHOR]

The fundamental significance of using cattle manure as a case study is the risk of continuing pollution, caused by its poor management in connection to the increasing demand for animal-derived food. Pyrolysis and gasification, effective solutions with real valorization potential, are the proposed techniques of converting this type of waste into valuable products. After a complete initial characterization, cattle manure is converted into hydrogen-rich syngas, using a modular hybrid fixed-bed reactor, at a generous thermal range, 700 °C to 875 °C, under different process agents, without the use of steam or the addition of catalysts. In comparison to gasification, the quantification of syngas demonstrates higher yields in pyrolysis processes, but with a lower energy potential. The content of the syngas in hydrogen, ⁓ 25 vol% and hydrocarbons, ⁓ 25 vol%, emphasized by an energetic value of ⁓ 17 MJ/m3, holistically places the gasification process in a slight advantage in relation to pyrolysis, exceeding the values presented by other studies on similar matrices and technical conditions. The forecast investigation of syngas composition through polynomial functions shows a significant drop in hydrogen and hydrocarbon concentrations after the 80-min sampling period. [Display omitted] • Pyrolysis and gasification are potential options for cattle manure management. • The experiments were developed into an updraft fixed bed modular hybrid reactor. • The process gas is critical in determining the composition development of syngas. • Temperature variation alone did not disclose distinct trends. • Superior performance in average H 2 production is ascribed to gasification with 21 vol% CO 2. [ABSTRACT FROM AUTHOR]

The inoculation of compound microorganisms effectively processes lignocellulosic biomass and promotes the formation of humic acid (HA). However, the basic mechanism of HA formation in compost remains unclear. In this study, we comprehensively characterized the transformation of HA molecules during co-composting. The addition of compound microorganisms enhanced the degradation of proteinoids and lignocellulose in the dissolved organic matter (OM), thereby accelerating the humification of bagasse cow dung co-compost. Elemental and UV–Vis spectral analyses showed that inoculation with the compound microorganisms enhanced the oxidation level and aromatization of the HA structure. Furthermore, two-dimensional Fourier-transform infrared spectroscopy correlation analysis suggested that the addition of compound microorganisms accelerated the decomposition and oxidation of OM. Accordingly, premature aggregation of HA was avoided, and the side chains bonded to HA were more abundant, promoting the evolution of HA to higher-order structures. By influencing the degree of aromaticity, molecular weight, and the C2 fluorescence peak of HA, the inoculation of compound microorganisms promoted HA synthesis during bagasse composting. These results provide an important basis for revealing the mechanism by which compound microorganisms are inoculated to promote HA formation at the molecular level and serve as a reference for the production of high-quality and high-maturity compost. [Display omitted] • HA formation was studied from element properties to molecular evolution. • The structural evolution of bioaugmentation-promoted HA formation was studied. • Structural distribution of HA was a key factor affecting humification. • Inoculation enhanced transformation of lignocellulose and protein-like substances. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanobubble water was first used to improve the CE efficiency of cow manure AD. • NBW enhanced the electron transfer efficiency of the cow manure AD system. • NBW enhanced cow manure degradation. • NBW enhanced carbohydrate metabolism and ABC transporters for MCCAs synthesis. • NBW enhanced fatty acid recycling pathway of chain elongation. Nanobubble water promotes the degradation of difficult-to-degrade organic matter, improves the activity of electron transfer systems during anaerobic digestion, and optimizes the composition of anaerobic microbial communities. Therefore, this study proposes the use of nanobubble water to improve the yield of medium chain carboxylic acids produced from cow manure by chain elongation. The experiment was divided into two stages: the first stage involved the acidification of cow manure to produce volatile acidic fatty acids as electron acceptors, and the second phase involved the addition of lactic acid as an electron donor for the chain elongation. Three experimental groups were established, and air, H 2 , and N 2 nanobubble water were added in the second stage. Equal amounts of deionized water were added in the control group. The results showed that nanobubble water supplemented with air significantly increased the caproic acid concentration to 15.10 g/L, which was 55.03 % greater than that of the control group. The relative abundances of Bacillus and Caproiciproducens , which are involved in chain elongation, and Syntrophomonas , which is involved in electron transfer, increased. The unique ability of air nanobubble water supplemented to break down the cellulose matrix resulted in further decomposition of the recalcitrant material in cow manure. This effect subsequently increased the number of microorganisms associated with lignocellulose degradation, increasing carbohydrate metabolism and ATP-binding cassette transporter protein activity and enhancing fatty acid cycling pathways during chain elongation. Ultimately, this approach enabled the efficient production of medium chain carboxylic acids. [ABSTRACT FROM AUTHOR]

• The concentration of ARB was about 103 to 106 CFU/g-dry in the raw material. • E. coli and ARB were not detected after the higher temperature than 150 °C of HTT. • The reduction of ARG was 2.9-log under the operating condition of 175 °C and 120 min. • The GI of diluted samples exceeded 90 %, except for 200 °C of temperature condition. • The operating condition of 175 °C and 120 min for HTT was recommended. In this study, the reduction in the abundance of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) and the fertilizer potential of liquid products from hydrothermally treated cattle manure were investigated. Hydrothermal treatment (HTT) was conducted under different reaction temperatures (125, 150, 175 and 200 °C) and retention times (60, 90 and 120 min). The total organic carbon (TOC) and total nitrogen (TN) of the liquid product increased with increasing reaction temperature. The germination index (GI), a measure of the percentage of germination, exceeded 90 % at 125, 150, and 175 °C in diluted samples, while it decreased to 18 % at 200 °C. Although a longer retention time contributed to an increase in TOC of liquid products, it did not increase the GI values. The liquid product should be diluted or adjusted before use as fertilizer to prevent phytotoxicity. In our analysis of ARB and ARGs, E. coli and antibiotic-resistant E. coli were completely reduced after HTT, except for the operating conditions of 125 °C and 60 min. Although both a higher reaction temperature and longer retention time tended to be better for the reduction of ARGs and intI1, it was found that the longer retention time is much more effective than the higher reaction temperature. The reduction of target ARGs and intI1 was 2.9-log under175 °C and 120 min. Comprehensively considering the fertilizer potential of liquid product and the reduction of ARB and ARGs, 175 °C of reaction temperature and 120 min of retention time of operating conditions for HTT were recommended. [ABSTRACT FROM AUTHOR]

[Display omitted] • Using statistics provided best anaerobic digestion conditions for cattle manure. • The most effective pretreatment was thermal treatment at 129.3℃ for 49.6 min. • Optimal mixing ratio of cattle manure, food waste, and pig manure was 30.5:42.5:27. • The ideal co-digestion condition substantially improves synergy effect and stability. This study investigated the optimal pretreatment condition and mixture ratio of cattle manure (CM) for its efficient anaerobic co-digestion (AcoD) with food waste (FW) and pig manure (PM). The pretreatment performances of thermal (TM), microwave (MW), and ultrasound (US) technologies and the AcoD performance were statistically and experimentally evaluated at various mixture ratios of CM, FW, and PM. The results revealed that the most effective pretreatment condition with the TM, MW, and US pretreatments was 129.3 °C for 49.6 min, 824.2 W for 7.3 min, and 418.0 W for 36.3 min, respectively. The best AcoD performance of optimally pretreated CM (PCM) was achieved when 30.5 % PCM was mixed with 42.5 % FW and 27.0 % PM. A long-term evaluation showed that the start-up rate for the anaerobic mono-digestion of PCM was 2.3 times faster than that of CM and the amount of methane produced was 4.7 times higher; process stability was thus preferentially maintained under a higher organic loading rate (OLR) (2.0 kg-VS/m3∙d). The start-up rate for the AcoD of PCM with FW and PM was 1.2 times higher than that of the AcoD of CM with FW and PM. Although the performance gap between the AcoD reactors after steady state was not significantly different, the PCM AcoD reactor provided a more stable operation under a higher OLR (5.0 kg-VS/m3∙d). This study demonstrates that the pretreatment and co-digestion of CM could significantly enhance the production of biogas and improve process stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A comprehensive database was established and conducted a series of meta -analysis. • Aerobic composting can substantially reduce ARGs and MGEs (74.3%, 78.8%). • The 3rd to the 6th week is a stable and high reduction composting period. • Nano-iron as an additive improve 75.0% ARGs mitigation compared with the control. • The significance of composting duration has been overlooked in ARGs mitigation. The significant increase in antibiotic resistance genes (ARGs) in organic solid wastes (OSWs) has emerged as a major threat to the food chain. Aerobic composting is a widely used technology for OSW management, with the potential to influence the fate of AGRs. However, the variability of the ARG elimination effects reported in different studies has highlighted the uncertainty regarding the effects of composting on ARGs. To identify the potential of composting in reducing ARG and the factors (e.g., composting technologies and physiochemical properties) influence ARG changes, a meta -analysis was conducted with a database including 4,232 observations. The abundances of ARGs and mobile genetic elements (MGEs) can be substantially reduced by 74.3% and 78.8%, respectively, via aerobic composting. During composting, the ARG levels in chicken and swine manure tended to be reduced more significantly (81.7% and 78.0%) compared to those in cattle manure (52.3%) and sewage sludge (32.6%). The reduction rate of sulfonamide resistant genes was only 35.3%, which was much lower than those of other types. MGEs and composting duration (CD) were identified as the most important factors driving ARG changes during composting. These findings provide a comprehensive insight into the effects of composting on ARG reduction, which may help prevent the transmission in food systems. [ABSTRACT FROM AUTHOR]

• Increasing the potential of Adenostemma lavenia through some types of fertilizer. • Fertilizer application resulted in better growth of A. lavenia compared to control. • The secondary metabolite production is increased when fertilizer is added. • The PCA patterns in A. lavenia extract are clustered based on fertilizer types. • The combination of fertilizers leads to improved growth and chemical compounds. Adenostemma lavenia , a member of the Asteraceae family, possesses numerous medicinal properties, although it is not extensively cultivated. The objective of this research initiative is to determine the optimal fertilizer dosages that result in the optimal productivity of 11α-OH KA, a diterpenoid, phenolic, flavonoid, and terpenoid compounds, as well as growth, in A. lavenia. A one-factor randomized block design was employed with five fertilizer doses: without fertilizer (control), cow manure (20 tons ha−1) (F1), NPK (urea, SP-36, and KCl: 135, 100, 135 kg ha−1, respectively) (F2), the first combination consisting of cow manure (10 tons ha−1) + NPK (urea, SP-36, and KCl: 67.5, 50, 67.5 kg ha−1, respectively) (F3), and the second combination consisting of cow manure (20 tons ha−1) + NPK (urea, SP-36, and KCl: 135, 100, 135 kg ha−1, respectively) (F4). The application of fertilizers stimulates plant development. LC-MS/MS analysis of the methanol extract of A. lavenia revealed the presence of the following compounds: 2 additional compounds, 7 terpenoids, 3 alkaloids, 3 phenolics, 2 fatty acids, 1 flavonoid, and 1 steroid. Combining F2, F3, and F4 makes it possible to produce plants with the highest leaf number, number of branches, and height. The combination of F4 generated the highest phenolic and flavonoid yields (409.88 μmol Gallic Acid Equivalent/plant) and 69.71 μmol Quercetin Equivalent/plant. These yields were not significantly different from those obtained when F2 and F3 were applied. Additionally, F4 produced the highest terpenoids and 11α-OH KA yields (61.48 mmol Nerol Equivalent/plant) and 29.81 mM 11α-OH KA/plant. The medical potential of A. lavenia can be enhanced by applying a mixture consisting of NPK (urea, SP-36, and KCl in a ratio of 135 kg ha−1, respectively) and cow manure (20 tons ha−1). [ABSTRACT FROM AUTHOR]

[Display omitted] • Two tracer types were used to discover the distribution of residence times (RT). • Transient was distinguished from steady-state based on lower RT and temperatures. • At steady-state 60% of the mean RT are estimated for 10% of the particles. • At transient-state the risk of insufficient hygienization increases. • Mass distribution of ball-shaped aggregates discharged from the drum was assessed. Rotary drums enable rapid composting compared to static systems. Residence times (RT) of 3–5 days are commonly applied to fulfill sanitary requirements and ensure the initial stabilization of organic matter. Practically, RT distribution (RTD) implies that a portion of the feed is discharged earlier than the mean RT, which may not guarantee safe application of the end product. This study assessed RTD and other physical–chemical and biological parameters of cattle manure and green waste composted in an EcodrumTM rotary drum (∼10 m3). Two types of tracers were used: pieces of plastic tubing and lumps of raw material in which plant seeds were buried, which were packed in nylon socks. A transient-state during which less than 50 % of the drum volume was occupied was distinguished from a steady-state stage, during which the drum operated with its optimal loading of about two-thirds of its volume. Starting temperatures inside the drum were close to ambient when the drum was mostly empty and then increased up to 60–65 °C as the occupied volume approached 50 %. The two types of tracers seemed to provide complementary measurements; under steady-state conditions, actual RTs were 60 % of the mean RT for 10 % of the feed material. The viability of plant seeds which were included in tracers was somewhat dependent on the specific RT. Under transient-state conditions, even shorter RTs (relative to the mean RT) are expected, coupled with non-thermophilic conditions, reducing the likelihood of adequate destruction of pathogens. [ABSTRACT FROM AUTHOR]

• Thermal pretreatment had negative/no effect on larval performance. • Mechanical pretreatment increased bioconversion rate for both substrates. • Bioconversion rate of grass clippings improved by 23–44%. • Mechanical pretreatment affected physical properties and microbial respiration. Black soldier fly larvae (BSFL , Hermetia illucens (L.)) are recognized for efficient biowaste reduction while yielding valuable proteins and fats for animals. However, lignocellulosic fibers in biowastes are difficult to digest by biowaste and larval digestive tract microorganisms as well as the larvae themselves. This study investigated two biowaste physical pretreatments (thermal, mechanical) for improving BSFL processing of fibrous biowastes. Cow manure, spent grain, and grass clippings were thermally pretreated at 90 °C for three durations (0.5, 1 and 4 h). Contrary to expectations, thermal pretreatment resulted in either no improvement or decreased larval performance on all substrates, regardless of treatment duration. In contrast, mechanical pretreatment of spent grain and grass clippings, involving milling with three screen sizes (0.5, 1 and 2 mm) showed promising results. Specifically, bioconversion rates on 0.5 mm-milled spent grain and grass clippings increased by 0–53 % and 25–44 % dry mass, respectively compared to untreated. Additionally, larval protein conversion increased by 41 % and 23 % on spent grain and grass clippings, respectively. However, mechanical pretreatment did not affect fiber degradation by larval conversion, as hemicellulose decreased by 25 % and 75 % for spent grain and grass clippings, respectively, regardless of particle size. Particle size reduction influenced substrate microbial respiration (CO 2 mg/min), with 0.5-mm milled grass clippings exhibiting higher respiration compared to untreated, although this effect was not observed for spent grain. This study highlights mechanical pretreatment's potential in enhancing BSFL bioconversion of fibrous biowastes and the importance of understanding substrate physical properties influencing substrate microorganisms and BSFL. [ABSTRACT FROM AUTHOR]

Intensive fossil fuel use has caused substantial climate change that induces various environmental and economic concerns. Developing clean and renewable energy is critical to mitigating such climate impacts. Manure-based biopower is attractive because the application is not complicated, and the biomass is generally supplied constantly. This study employs a lifecycle framework to evaluate the power potential, economic profits, and environmental benefits of manure application in Taiwan. The results show that (1) Up to 2,304 GWh can be generated annually, in which hog manure contributes the most, (2) Profits of hog manure range from $104-$119 million and up to $59 million for cattle manure energy sale. Using chicken manure is less profitable but could still be a valuable addition to biopower production. (3) Promoting green finance could partly eliminate the investment risk of large-scale manure applications. • Manure application would provide up to 2,304 GWh of electricity annually. • Low energy and emission prices would increase investment risk. • Establishing a local emission trade mechanism encourages biogas power development. • The gain of digestate application on cropland is as important as energy sales. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) are an important tool that generates electricity from waste biomass. Polymer electron membrane supported dual-chamber MFCs are one of the most tested microbial fuel cells. The most important factor affecting performance in this system is the proton transfer capability of the membrane. In this study, zirconia based metal organic frameworks (Zr-MOF) doped porous membranes were produced, characterized and used in dual chamber (H-type) MFC to generate electricity from animal manure (Cow manure). The effects of MOF ratio on membrane's physical, chemical properties, and on the cell performance were investigated. The incorporation of MOF into the PVDF matrix improved the water retention property of the membrane. The Zr-MOF addition increased the mechanical strength from 0.55 MPa to 1.52 MPa. The cation exchange capacity increased from 1.04 mmol/g to 2.41 mmol/g. It significantly increased the cell electricity production from 0.186V to 0.49V. The power density values are obtained as 5.02 and 13.8 mW/m2 with the pristine and Zr-MOF(4)-PVDF membranes, respectively. • H type MFC with porous PVDF membrane was investigated. • Zr-MOF was synthesized and used for filler in PVDF membrane. • Zr-MOF addition increased the mechanical strength from 0.55 to 1.52 MPa. • The cation exchange capacity increased from 1.04 to 2.41 mmol/g. • The cell electricity production increased from 0.186V to 0.49V. [ABSTRACT FROM AUTHOR]

• Throughout cattle manure composting, average airflow resistance decreased by 40.1%. • All research parameters had the greatest variation at the thermophilic phase. • With the aerobic reaction, the total pressure ought to be adjusted to a lower level. • Ranks affecting airflow resistance were bulk density, particle size, specific gravity. Composting is widely adopted in livestock waste management, and the ventilation system control is essential for composting efficiency. For ventilation system, the airflow resistance is a major factor influencing the ventilation intensity and oxygen supply capacity. This study explored the variation law of airflow resistance, bulk density, specific gravity, particle size and total pressure throughout composting with cattle manure. The airflow resistance was calculated with Ergun equation, and contribution coefficients of different components were analyzed with principal component analysis (PCA). Results showed that the viscous airflow resistance was dominant throughout cattle manure composting. The average airflow resistance was 0.146 Pa/m, and resistance of pile at lower layer was higher than that at the upper layer by 18.1 %. For contribution coefficient affecting airflow resistance, the ranks were bulk density, average particle size and specific gravity. During composting process, the average airflow resistance decreased by 40.1 % and the total pressure reduced by 3.47 %. All parameters had the greatest variation at thermophilic phase, which accounted for more than 60 % of the total variation amplitude. Meanwhile, less than 10 % of the total pressure was used to overcome the airflow resistance. Therefore, reducing bulk density of pile should be considered preferentially to decrease the airflow resistance. During cattle manure composting process, the total pressure of ventilation system ought to be adjusted with the aerobic reaction to a lower level, especially at thermophilic phase with the most rapid descent rate. This study can provide support for reducing the energy consumption required for ventilation of composting. [ABSTRACT FROM AUTHOR]

The assessment of anaerobic biotransformation in thermophilic mode (55 °C) of agricultural waste was carried out. It has been established that organic wastes (wheat distillery vinasse, cow manure and chicken manure) have a great potential for producing biogas with a high content of methane and carbon dioxide with a low content of impurities. Biogas can be recommended as a raw material for hydrogen production. With the ratio of components in the composition of the mixed substrate of distillery vinasse, cow manure and chicken manure - 6: 3: 1 for 21–29 days of anaerobic digestion, the best indicators of the efficiency of methanogenesis for methane (61–63%) and biogas (70–73%) were provided, the share of methane in composition of biogas was 61%. With the biotransformation of alone vinasse, the nitrogen mineralization efficiency (58–67%) was lower than when using a mixture of organic waste (63–69%). From the point of view of obtaining the maximum amount of biogas, it is advisable to add a carbonate buffer or limestone flour (9% wt.) to the substrate to shift the pH of the working solution towards slightly alkaline values. From the point of view of the accumulation of free phosphates in the final solution, the use of a carbonate buffer is more preferable. The anaerobically treated solid sludge remaining after biogas production, as well as liquid effluents (anaerobically treated effluents) can be considered as potential organic and biogenic fertilizers or their components. [ABSTRACT FROM AUTHOR]

Biological dihydrogen (H 2) production is a promising alternative to the conventional non-renewable energies. H 2 production by dark fermentation is particularly studied regarding its independence from fossil fuel and electricity, its cultivation into bioreactors and the broad range of substrate that can be used. A major goal application of dark fermentation is the valuation of wastes. In this context, cheese whey wastes are particularly adapted, since rich in organic matter, abundant and low cost. A novel H 2 -producing strain was isolated from a sample of mixed bovine manure and cheese whey, collected in a cheese-producing dairy farm. The strain was identified as a Clostridium beijerinckii strain based on morphological and physiological characteristics, and 16S rDNA sequencing. The optimum temperature and pH for H 2 production was 40 °C and pH 7, respectively. Substrate and stress tolerance tests showed that C. beijerinckii C.sp.1.3 could produce H 2 from glucose, lactose, maltose, cellobiose, galacturonic acid, xylose, and sucrose, and to a lesser extent from starch, cellulose and glycerol. The H 2 production potential from a mix of dairy industrial wastes of this strain has been evaluated. The highest productivity in batch for 5 g L−1 of Total Organic Carbon (TOC) was 833.1 mL H 2 L−1 d−1, with a yield of 2.03 mM H2 mM lactose −1, demonstrating the potential of this strain for H 2 production from industrial wastes. • An H 2 -producing strain was isolated from a mixture of manure and dairy waste. • The strain has the potential of fermenting a broad range of economic substrates. • Mixture of crude cheese whey and wastewater were used as model for H 2 production. • Productivity reach up to 833.1 mL L−1 d−1 with a yield of 2.03 mol H2.mol lactose −1. • A mechanism of lactate-driven fermentation was observed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Poultry carcass composting systems using woodchips and biochar were modeled. • The goal was to elucidate how biochar increases carcass compost temperatures. • When biochar was mixed, the total heat unit increased by 11.22 ± 3.17 %. • Layering biochar resulted in a smaller increase in the total heat unit, up to 8.7% • It was concluded that biochar's primary role was promoting microbial activity. Previous studies reported that incorporating biochar into composting systems leads to an increase in compost temperatures. Although potential reasons, such as improved microbial activity or increased insulation, were suggested, no study has quantitatively determined the contribution of either aspect. In this study, we developed a heat transfer model for a biochar-amended co-composting system based on the measurements from our two previously published studies conducted to co-compost poultry carcasses with woodchips and wood-based (WBC), distillers grain (DGBC), and cow manure (CMB) biochar. The two composting studies were conducted over three heating cycles, with two turnings separating each cycle. The simulation for the second heating cycle, during which the compost materials began to degrade and were well-mixed, showed an average R2 value of 0.86 and was selected for further analyses. Results from the model suggested that incorporating biochar into the composting mixture increases thermal conductive losses. For example, at a biochar addition rate of 13 % (v/v), the predicted longitudinal conductive resistance of the compost pile was reduced by 24.9 %. However, the total heat unit still increased by 11.2 ± 3.17 % due to the enhancement of microbial activity as supported by elevated oxygen consumption (38.1–61.1 %). When biochar was applied in layers on the surface of the composting bins, its impact on microbial activity was minimal, primarily functioning as an insulator. Under these conditions, the total heat unit was 8.7 % higher than the control. These findings suggest that biochar's primary effect on temperature development was through promoting microbial activity. [ABSTRACT FROM AUTHOR]

The growth and chemical composition of essential oils (EOs) depend on several factors in particular the supply of fertilization. The use of fertilization with different manure sources and doses in a sustainable production system are critical factors in integrated nutrient management and play an important role in increasing of quantity and quality of medicinal plant. Furthermore, organic manures play an important role in the growth of plants leading to organic and cleaner production. Hence, a field experiment was conducted to study the usage of different organic manures and chemical fertilizers on biomass production, accumulation of nutrients in the leaves, essential oil content, essential oil yield and chemical compositions of Thymus vulgaris. In addition to these objectives, providing an economical and low-cost alternative with the use of organic fertilizers. The treatments consisted of: three sources of organic manure (quail, cattle, and goat) at four doses, chemical fertilizer and the control (without fertilizer). Significant differences were observed between manure sources and doses in virtually all response variables. The results showed that the highest biomass and leaf nutrients of T. vulgaris was obtained in plants treated with quail and cattle manure. Higher production of reactive oxygen species was observed in plants fertilized with goat manure, which generally showed the lowest levels of leaf nutrients. The results showed that the highest essential oil yield of T. vulgaris was obtained in plants treated with cattle manure compared to the control treatment. Thymol was major chemical compound of thyme tended to increase with increasing doses of the three sources of organic manures. The present study indicated that the usage of the right dose and source organic manure are crucial to provide quantitative-qualitative gains in the cultivation of T. vulgaris. [Display omitted] • Quail manure requires lower doses for better growth of thyme plants. • Quail and cattle manure provided a higher dry weight gain than chemical fertilization. • Higher doses of cattle manure had the highest contents and yields of essential oils. • Thymol tended to increase with increasing doses of the three sources of manure. • Higher production of reactive oxygen species was observed with goat manure. [ABSTRACT FROM AUTHOR]

[Display omitted] • A life cycle costing method was developed to optimize the cow raising system. • Using manure as fertilizer yields the greatest environmental and economic benefits. • Manure management choices are responsible for 58% of the carbon footprint variation. • Investment in fertilizer utilization yields up to a 3-fold environmental benefit. • Chinese milk production may reach a carbon peak value of 69 Mt CO 2 eq by 2057. Waste management signifies an equilibrium between environmental and economic factors. However, a comprehensive understanding of the integrated life cycle environmental-economic performance of waste management activities remains unclear. To facilitate a systematic linkage between the economic and environmental sectors, a regionalized life cycle assessment-based life cycle costing method was developed based on China's actual status quo. The cow manure utilization was set as an entry point to explored long-term environmental-economic performance of milk production under various manure utilization pathways. The results show that trade-offs were observed between internal and external costs as well as various environmental indicators. The choice of waste utilization is the focal point of environmental-economic trade-offs in the cow raising system. The optimal environmental-economic performance was achieved through the manure fertilizer utilization pathway, yielding a remarkable three-fold increase in marginal environmental benefits. Compared with fertilizer utilization, the manure direct returning to field reduced the carbon footprint by 12% while induced an external cost of $14.3. The wastewater treatment pathway is $ 5.5 lower in internal costs but $ 11.7 higher in external costs than those of fertilizer utilization. Overall, utilizing manure has potential to mitigate the upward trend of carbon footprint and external costs. However, achieving the carbon peak remains a significant challenge. A promising solution is the recycling of straw resources within cropping systems, particularly in hotspot regions (e.g., Inner Mongolia, Heilongjiang, Hebei, and Shandong). A comprehensive analysis of the dynamic interplay between cropping systems and cow raising systems is critical steps towards realizing a carbon-neutral future within the dairy production. [ABSTRACT FROM AUTHOR]

Enhanced biohydrogen production from high loads of unpretreated cattle manure by hyperthermophilic Caldicellulosiruptor bescii. [Display omitted] • First use of raw manure as sole carbon source for hyperthermophilic H 2 production. • Adaptation of C. bescii provided maximum H 2 production yield of 161 mL/g VS added. • Maximum mass solubilization of unpretreated cattle manure was around 73%. • Sparging with N 2 /CO 2 mixture lowers product inhibition impacts and enhances yield. • Carbon balance was complete for fermentation of cattle manure at 75 °C. Caldicellulosiruptor bescii is the most thermophilic cellulolytic bacterium capable of fermenting crystalline cellulose identified to date, and it also has a superior ability to degrade plant biomass without any pretreatment. This study is the first to assess the potential of utilizing unpretreated cattle manure (UCM) as a feedstock for hydrogen (H 2) production by C. bescii at a concentration range between 2.5–50 g volatile solids (VS)/L. At 50 g VS/L UCM concentrations, H 2 production ceased due to inhibition of C. bescii. To alleviate the impacts of inhibition, two strategies were adopted: (i) reduction of H 2 build-up in the reactor headspace via gas sparging and (ii) adaptation of C. bescii to UCM via adaptive laboratory evolution (ALE). The former increased H 2 yield by 47% compared to the control reactors, where no sparging was applied. The latter increased H 2 yield by 142% compared to the control reactors inoculated by the wild type C. bescii. The UCM-adapted C. bescii demonstrated a remarkable H 2 yield of 161.3 ± 1.6 mL H 2 /g VS added at 15 g VS/L. This yield represents a twofold increase compared to the maximum H 2 yield reported in the literature amongst fermentation studies utilizing manure as feed. At 15 g VS/L, around 73% of UCM was solubilized, and the carbon balance indicated that most of the effluent carbon was in the sugar- and acid-form. The remarkable ability of C. bescii to produce H 2 from UCM under non-sterile conditions presents a significant potential for sustainable biohydrogen production from renewable feedstocks. [ABSTRACT FROM AUTHOR]

[Display omitted] • A large-scale survey uncovered bacterial wilt suppressiveness (BWS) of compost. • BWS was linked to rhizosphere microbiome but not compost properties. • BWS of compost was regenerative. Composts are often suppressive to several plant diseases, including the devastating bacterial wilt caused by Ralstonia solanacearum. However, the underlying mechanisms are still unclear. Herein, we carried out an experiment with 38 composts collected from different factories in China to study the interlinking among bacterial wilt suppression, the physicochemical properties and bacterial community of the compost, and bacterial community in the rhizosphere of tomato fertilized by compost. Totally 26 composts were suppressive to bacterial wilt, while six composts stimulated the disease. The control efficiency was neither correlated with physicochemical properties (TC, TN, P and K, pH or GI) nor bacterial community of compost, but with rhizosphere bacterial community (r = 0.17, p = 0.016). The control efficiency was also positive correlated with taxa (Rhizobium, Aeromicrobium) known suppressive to R. solanacearum. The mushroom spent or cow manure, from which the two composts were 100% and 77% in control efficiencies against bacterial wilt respectively were subject to a pilot-scale composting reaction. The reproduced composts from mushroom spent or cow manure were only 57% and 23% effective on the control of bacterial wilt, respectively. The analysis of bacterial communities revealed that the relative abundances of R. solanacearum were 28.4% for the control, but only 7.8%-7.9% for compost fertilized tomatoes. The compost from mushroom spent also exerted a strong effect on rhizosphere bacterial community. Taken together, most composts were suppressive to bacterial wilt possibly also by modifying rhizosphere bacterial community towards inhibiting the colonization of R. solanacearum and selecting for beneficial genera of Proteobacteria, Bacteroidetes and Actinobacteria. [ABSTRACT FROM AUTHOR]

[Display omitted] • Newly ammonifying microorganisms cultures were inoculated into cow manure compost. • AM increased the count and viability of microbial cells during composting. • Amm-4 enhanced the ammonification, sequestration, and conversion of nitrogen. • Provides a novel approach to manure management, and environmental pollution control. It is essential to reduce nitrogen losses and to improve nitrogen conversion during organic waste composting because of environmental protection and sustainable development. To reveal newly domesticated ammonifying microorganisms (AM) cultures on the ammonification and nitrogen conversion during the composting, the screened microbial agents were inoculated at 5 % concentration (in weight basis) into cow manure compost under five different treatments: sterilized distilled water (Control), Amm-1 (mesophilic fungus-F1), Amm-2 (mesophilic bacterium-Z1), Amm-3 (thermotolerant bacterium-Z2), and Amm-4 (consortium: F1, Z1, and Z2), and composted for 42 days. Compared to control, AM inoculation prolonged the thermophilic phases to 9–19 days, increased the content of NH 4 +-N to 1.60–1.96 g/kg in the thermophilic phase, reduced N 2 O and NH 3 emissions by 22.85–61.13 % and 8.45–23.29 %, increased total Kjeldahl nitrogen, and improved cell count and viability by 12.09–71.33 % and 66.71–72.91 %. AM was significantly associated with different nitrogen and microbial compositions. The structural equation model (SEM) reveals NH 4 +-N is the preferable nitrogen for the majority of bacterial and fungal growth and that AM is closely associated with the conversion between NH 3 and NH 4 +-N. Among the treatments, inoculation with Amm-4 was more effective, as it significantly enhanced the driving effect of the critical microbial composition on nitrogen conversion and accelerated nitrogen ammonification and sequestration. This study provided new concepts for the dynamics of microbial in the ammonification process of new AM bacterial agents in cow manure compost, and an understanding of the ecological mechanism underlying the ammonification process and its contribution to nitrogen (N) cycling from the perspective of microbial communities. [ABSTRACT FROM AUTHOR]

• The fate of FIB and of pathogenic bacteria though AD varied with the biogas plant. • log 10 reductions of pathogenic bacteria though AD varied over time. • Campylobacter and Salmonella were less persistent than L. monocytogenes. • The reduction of C. botulinum and C. difficile were less than or equal to 0.5 log 10. Interest in the conversion of manure in biogas via anaerobic digestion (AD) is growing, but questions remain about the biosafety of digestates. For a period of one year, we monitored the impact of three mesophilic agricultural biogas plants (BPs) mainly fed with pig manure (BP1, BP3) or bovine manure (BP2) on the physicochemical parameters, the composition of the microbial community and the concentration of bacteria (E. coli , enterococci, Salmonella, Campylobacter, Listeria monocytogenes, Clostridium perfringens, Clostridium botulinum and Clostridioides difficile). The BP2 digestate differed from those of the two other BPs with a higher nitrogen content, more total solids and greater abundance of Clostridia MBA03 and Disgonomonadacea. Persistence during digestion ranked from least to most, was: Campylobacter (1.6 to >2.9 log 10 reduction, according to the BP) < E. coli (1.8 to 2.2 log 10) < Salmonella (1.1 to 1.4 log 10) < enterococci (0.2 to 1.2 log 10) and C. perfringens (0.2 to 1 log 10) < L. monocytogenes (-1.2 to 1.6 log 10) < C. difficile and C. botulinum (≤0.5 log 10). No statistical link was found between the reduction in the concentration of the targeted bacteria and the physicochemical and operational parameters likely to have an effect (NH 3 , volatile fatty acids and total solids contents, hydraulic retention time, presence of co-substrates), underlining the fact that the fate of the bacteria during mesophilic digestion depends on many interacting factors. The reduction in concentrations varied significantly over the sampling period, underlining the need for longitudinal studies to estimate the impact of AD on pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

[Display omitted] • Manure and manure-derived hydrochar addition increased soil pH by 0.3–1.0 units. • Manure-derived hydrochar reduced floodwater NH 4 +-N and TP compared to manure. • Manure-derived hydrochar helps reduce non-point source (N and P) pollution. • Manure-derived hydrochar inhibited soil urease and acid phosphatase activity. • HTC of pig manure has better fertility than cattle manure in soil–water systems. Hydrothermal carbonization (HTC) technology is an emerging technology for the disposal of manure-based wet wastes. However, the effects of manure-derived hydrochar inputs to agricultural soils on nitrogen (N) and phosphorus (P) morphology and conversion in soil–water systems remain largely unexplored. In this study, pig and cattle manure (PM and CM), and their derived hydrochar (PCs and CCs) were applied to agricultural soils, with changes in nutrient morphology and enzyme activities related to N and P transformation in the soil–water systems observed through flooded incubation experiments. The results showed that floodwater ammonia N concentrations were reduced by 12.9–29.6% for PCs relative to PM, and 21.6–36.9% for CCs relative to CM, respectively. Moreover, floodwater total P concentrations of PCs and CCs were reduced by 11.7–20.7% relative to PM and CM. Soil enzyme activities closely related to N and P transformations in the soil–water system responded differently to manure and manure-derived hydrochar application. Compared to manure, the application of manure-derived hydrochar inhibited soil urease and acid phosphatase activity by up to 59.4% and 20.3%, respectively, whereas it had significant promotion effects on soil nitrate reductase (∼69.7%) and soil nitrite reductase (∼64.0%). The products of manure after HTC treatments have the characteristics of organic fertilizers, and the fertilization effects of PCs are more prominent than CCs, which are subject to further verification in field trials. Our findings improve the current understanding of manure-derived organic matter affecting N and P conversions in soil–water systems and the risk for non-point source pollution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrothermal treatment of cow manure with acids promotes the extraction of P and N. • Phosphorus-containing solids can precipitate from HTC process water. • HTC with formic or sulfuric acid results in a high phosphorus precipitation yield. • Precipitation and recovery of P is as high as 99% • Precipitation and recovery of N was less than 25% The work studies the recovery of nutrients (phosphorus and nitrogen) from the process water of acid-assisted hydrothermal carbonization (HTC) of cow manure. Three organic acids (formic acid, oxalic acid, and citric acid) and sulfuric acid were evaluated as additives in HTC. Using 0.3 M sulfuric acid, more than 99% of phosphorus and 15.6% of nitrogen from manure are extracted and dissolved during HTC at 170 °C with 10 min reaction time in a batch reactor. Nutrients (mainly phosphorus) were recovered through precipitation from process water by raising the ionic strength of the solution by addition of salts of magnesium and ammonia, and by raising the pH to 9.5. Subsequently, phosphorus-rich solids were recovered containing almost all (greater than 95%) of the dissolved phosphorus in the sulfuric and formic acid assisted runs. Morphology and qualitative chemical analysis of the precipitates were determined. It is shown by XRD that the precipitate formed from process water generated by HTC with oxalic acid is crystalline, although the diffraction pattern could not be matched with any expected substance. [ABSTRACT FROM AUTHOR]

• Dairy manure storage led to a 20.5% BMP decrease from barn to outdoor storage. • Pig manure storage led to a 39.5% BMP decrease from intermediate to outdoor storage. • The BMP of pig manure declined faster than BMP of cow manure. • Important to feed manure to biogas plants rapidly to avoid significant CH 4 emissions. Biogas production is a suitable option for producing energy from dairy and pig manure types. During manure storage, organic matter degradation results in methane emissions decreasing the potential biogas yield. The present research advances the understanding of the biochemical methane potential (BMP) and the chemical characteristics of manure collected year-round from sequential stages of the liquid manure management chain of commercial dairy cow and pig farms. To this end, manure samples from six livestock farms in Germany were analyzed. The results showed that changes in chemical composition during storage led to a 20.5% decrease in the BMP of dairy manure from the barn to outdoor storage. For fattening pig manure samples, there was a 39.5% decrease in the BMP from intermediate to outdoor storage. An analysis of BMP according to manure age showed that pig manure degrades faster than dairy manure; the importance of promptly feeding manure to the biogas plant in order to avoid significant CH 4 emission losses and reduction in energy producing capacity was highlighted. The best BMP predictors for dairy manure were the contents of dry matter, volatile solids and lignin, whereas best BMP predictors for pig manure were dry matter and volatile fatty acid (VFA) content. Prediction models performed well for samples from outdoor storages; refinements for predicting BMP of less aged samples presenting lower chemical variability would be necessary. [ABSTRACT FROM AUTHOR]

During the processing of raw agricultural materials from the primary sector, large quantities of by-products with high chemical energy content are produced. Some of these are olive mill wastewater (OMW), cheese whey (CW), and liquid cow manure (LCM). Anaerobic digestion is a promising, environmentally friendly process for the energy valorization of agro-industrial and livestock by-products. The purpose of this study was the mathematical modeling of anaerobic digestion in batch systems, aiming to quantify possible synergies occurring between complementary substrates. The analysis was based on using biochemical methane potential data to predict the optimum hydraulic retention time (HRT) under steady-state conditions of continuous systems, for different substrate ratios. The objective function for HRT optimization was based on maximizing the process profit and included technoeconomic parameters, allowing the comparison of the different substrate ratios that can be used in the feedstock. The co-digestion with a mixture ratio of OMW:LCM equal to 70:30 proved very satisfactory for the sustainability of the process, exhibiting a maximum net profit of 16 €/m3 reactor /d for a plant capacity of 10 m3 feed /d. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar reduces NH 3 emissions during cattle slurry storage up to 20% • Biochar improves the separation efficiency and the quality of the solid fraction. • Biochar increases C, (organic) N and water-available P in the solid fraction. • S° is only successful for reducing NH 3 emissions in combination with biochar. • Biochar results in a short term priming effect on the C mineralization of manure. Cattle slurry storage is a major source of gaseous N emissions. The aim of this study was to evaluate the effects of biochar, clinoptilolite and elemental sulfur (S°) on (1) NH 3 and greenhouse gas emissions during storage of cattle slurry and (2) after soil application of the enriched solid fractions; and (3) on the agronomic quality of the solid and liquid fractions. In the first phase, biochar was added to the slurry (10 g L-1); subsequently in the second phase, clinoptilolite (50 g L-1), S° (1 g L-1) and 40 g L-1 extra biochar were added. Gaseous emissions were monitored by a semi-continuous multi-gas analyzer and the agronomic quality of solid and liquid fractions was assessed after separation. The enriched solid fractions were applied to soil to study the effects on gaseous emissions, N and C mineralization. Amendment of biochar reduced NH 3 emissions during cattle slurry storage by 12% during the first 7 days. Extra amendment of biochar, clinoptilolite and S° in combination with biochar resulted in a decrease of NH 3 emissions of approximately 20%. The N sorbed from the slurry by the biochar was not released as NH 3 during soil application of the solid fractions and was not released as mineral N in the short term (within 28 days). A short-term positive priming effect of biochar on the C mineralization of manure and biochar-manure mixture applied to soil was observed. The biochar-enriched solid fractions contained more C, total and organic N and water-available P with a slow release. [ABSTRACT FROM AUTHOR]

The improper disposal of palm oil industrial waste has led to serious environmental pollution. In this study, we isolated Paenibacillus macerans strain I6, which can degrade oil palm empty fruit bunches generated by the palm oil industry in nutrient-free water, from bovine manure biocompost and sequenced its genome on PacBio RSII and Illumina NovaSeq 6000 platforms. We obtained 7.11 Mbp of genomic sequences with 52.9% GC content from strain I6. Strain I6 was phylogenetically closely related to P. macerans strains DSM24746 and DSM24 and was positioned close to the head of the branch containing strains I6, DSM24746, and DSM24 in the phylogenetic tree. We used the RAST (rapid annotation using subsystem technology) server to annotate the strain I6 genome and discovered genes related to biological saccharification; 496 genes were related to carbohydrate metabolism and 306 genes were related to amino acids and derivatives. Among them were carbohydrate-active enzymes (CAZymes), including 212 glycoside hydrolases. Up to 23.6% of the oil palm empty fruit bunches was degraded by strain I6 under anaerobic and nutrient-free conditions. Evaluation of the enzymatic activity of extracellular fractions of strain I6 showed that amylase and xylanase activity was highest when xylan was the carbon source. The high enzyme activity and the diversity in the associated genes may contribute to the efficient degradation of oil palm empty fruit bunches by strain I6. Our results indicate the potential utility of P. macerans strain I6 for lignocellulosic biomass degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochars made of different feedstocks co-composted with poultry carcasses. • Distillers grain biochar had the highest nitrogen in finished compost (p = 0.0009) • Wood-based and cow manure biochar addition increased peak temperatures by 2.0–3.3 °C. • Wood-based biochar addition reduced the cumulative leachate COD by 87% • Biochar amendments at 13% (v/v) did not reduce ammonia emissions (p = 0.856) Composting has been recognized as a viable method to dispose of animal carcasses. Common concerns related to the composting process include low core temperatures, leachate generation, and ammonia emissions. This study tested co-composting full-size poultry carcasses with commercially available biochars at an aeration rate of 0.8 L∙min−1. Biochars prepared by gasifying wood pallets, distillers' grains, and cow manure were added to the composting bins at the 13% rate (by volume). Results showed that poultry carcasses with wood-based and cow manure biochar increased temperatures by 2.0 to 3.3 °C. All biochar-amended bins met the time–temperature criteria to eliminate avian influenza (H7N1) viruses, which could not be achieved without biochar addition. Wood-based biochar amendment lowered the cumulative chemical oxygen demand of the leachate samples by 87% (P = 0.02). At the rate studied, the biochar amendment did not significantly affect ammonia emissions (P = 0.56). BET surface area of wood-based biochar was 1.4 and 28 times greater than that of cow manure and distillers' grain biochar, respectively. Compared to no biochar addition, wood-based biochar resulted in significantly higher compost temperatures (P = 0.02), lower leachate COD values (P = 0.02), and a higher total nitrogen content (P = 0.01) while it did not cause an increase in sodium content (P = 0.94) of the finished compost. In conclusion, amending the poultry carcass composting process with wood-based biochar (13% by volume) is recommended, especially to eliminate disease-causing agents. [ABSTRACT FROM AUTHOR]

• Ammonia pretreatment at 5 % decreased total fibers except with cow manure. • Ammonia pretreatment at 1 % had no effect on degradation of fibers. • Ammonia pretreatment decreased fly larvae performance. • Three-day fermentation improved larvae performance on cow manure and oat pulp. Biowaste treatment with black soldier fly larvae (BSFL, Hermetia illucens L.) can promote a more sustainable food system by reusing nutrients that would otherwise be wasted. However, many agri-food wastes and byproducts are typically high in lignocellulosic fibers (i.e., cellulose, hemicellulose, and lignin), making it resistant to efficient larval and/or microbial degradation. Ammonia pretreatment could be used to partially degrade lignocellulose, making the biowaste more easily degradable by the larvae and/or microorganisms. This study evaluated ammonia pretreatment for lignocellulose degradation and its effect on BSFL performance on four fibrous biowastes: brewers spent grain, cow manure, oat pulp, and grass clippings. First, the optimal ammonia dose (1 % or 5 % dry mass) and pretreatment time (three or seven days) were assessed by measuring fibers after treatment and further examined using Fourier transform infrared spectroscopy (FTIR) spectra and scanning electron microscopy (SEM) images. Second, BSFL rearing performance on ammonia-pretreated substrates was assessed with a 9-day feeding experiment. Three-day pretreatment with 5 % ammonia was chosen as it decreased the total fiber content by 8–23 % for all substrates except cow manure. Contrary to expectations, ammonia pretreatment with all substates decreased BSFL rearing performance metrics by more than half compared to the untreated control. Follow-up experiments suggested that ammonia pretreatment had a dose-dependent toxicity to BSFL. Interestingly, three-day fermentation of cow manure and oat pulp increased bioconversion rate by 25–31 %. This study shows that ammonia pretreatment is not suitable before BSFL rearing. Ammonia toxicity to BSFL and other pretreatments, such as fermentation, should be further studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • Using acetate is not advantageous for improving performance of manure-fed MECs. • Cross-feeding lowers methane production performance during electromethanogenesis. • To produce similar CH 4 from manure as acetate, two times greater sCOD is required. • Model exoelectrogen Geobacter dominated the anodes of all manure-fed MECs. • Hydrogenotrophic Methanoculleus is abundant on the cathodes of manure-fed MECs. This study qualitatively assessed the impacts of different start-up strategies on the performance of methane (CH 4) production from cattle manure (CM) in electromethanogenic reactors. Single chamber MECs were operated with an applied voltage of 0.7 V and the impact of electrode acclimatization with a simple substrate, acetate (ACE) vs a complex waste, CM, was compared. Upon biofilm formation on the sole carbon source (ACE or CM), several MECs (ACE_CM and CM_ACE) were subjected to cross-feeding (switching substrate to CM or ACE) during the test period to evaluate the impact of the primary substrate. Even though there was twice as much peak current density via feeding ACE during biofilm formation, this did not translate into higher CH 4 production during the test period, when reactors were fed with CM. Higher or similar CH 4 production was recorded in CM_CM reactors compared to ACE_CM at various soluble chemical oxygen demand (sCOD) concentrations. Additionally, feeding ACE as primary substrate did not significantly impact either COD removals or coulombic efficiencies. On the other hand, the use of anaerobic digester (AD) seed as an inoculum in CM-fed MECs (CM_CM), relative to no inoculum added MECs (Blank), increased the initial CH 4 production rate by 45% and reduced the start-up time by 20%. In CM-fed MECs, Geobacter dominated bacterial communities of bioanodes and hydrogenotrophic methanogen Methanoculleus dominated archaeal communities of biocathodes. Community cluster analysis revealed the significance of primary substrate in shaping electrode biofilm; thus, it should be carefully selected for successful start-up of electromethanogenic reactors treating wastes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new model for exogenous organic matter in soil is developed. • Two digestate incubations in soil were conducted and used as calibration datasets. • The model simulates accurately the main processes observed in soil. As its use in agriculture grows, the fate of digestate in soil raises concerns on many different levels. In particular, the degradability of its organic matter when spread on soil is still an ongoing topic. In an effort to better understand the processes and dynamics of digestate soil incubation, C and N mineralization kinetics obtained in 358 days long laboratory incubations during decomposition of digestates were simulated using a dynamic model. The model includes twelve compartments related through processes including 18 parameters. The main novelty of this model is the use of accessibility-related variables to describe the fate of exogenous organic matter in soil, thus enabling a detailed understanding of its outcome in soil. Model calibration on cattle manure digestate incubation resulted in the estimation of parameter values. The newly calibrated model was then tested on an energy crop digestate incubation experiment. The model was able to reproduce accurately the experimental behavior of most variables. [ABSTRACT FROM AUTHOR]

Anaerobic conversion technologies are common for organic waste processing. However, the overaccumulation of digestate remaining after anaerobic conversion of biomass requires consideration of new economically viable ways of its disposal. In this work, the possibility of using steam gasification of digestates after anaerobic digestion (AD) and dark fermentation (DF) of lignocellulosic biomass, in order to obtain syngas with high hydrogen content, was investigated. Several digestates were used as feedstocks: (1) after AD of cow manure and mixture of cow manure and amaranth, and (2) from a dark fermentation (DF) reactor fed with by-products of cereals, bran, sunflower meal and rape cake, and operating at hydraulic retention time of 1 and 2.5 days. A methodology for determining the performance indicators of gasification is presented. The thermochemical conversion temperature was 1000 °C. The main indicators of the gasification process were determined at steam to digestate ratios from 0.45 to 0.65. Syngas obtained by steam gasification of digestates contained up to 62.7% H 2 and up to 40.4% CO. The syngas from digestates after DF had high values of the molar ratio of H 2 to CO, from 1.9 to 2.3, which makes it promising for conversion to liquid fuel by Fischer-Tropsch synthesis. The lower heating value of the syngas from all digestates was in the range from 12.1 to 12.4 MJ/m3. A combination of biological and thermochemical conversion can be used to generate the maximum amount of hydrogen from agro-industrial waste. This study contributes to the creation of a closed technological cycle for the processing of large-tonnage waste in the agro-industrial complex with the production of high value-added products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Life cycle assessment of mono- and co-digestion for farm-scale biogas plants. • Co-digestion of manure with organic waste improved net environmental implications. • Reductions in climate change, eutrophication potential and terrestrial ecotoxicity. • Open storage of digestate is identified as hotspot of emissions. Proper management of biogenic residues, particularly livestock manure and food waste, is a major challenge for Bangladesh. While mono-digestion has traditionally been used on farms for treating manure, inadequate energetic output limits its applicability. Food waste, however, is typically landfilled in current practice. Co-digestion of biowaste emerged as an alternative due to synergistic yield and capacity to handle multiple waste streams. However, its environmental performance is underreported, particularly in developing countries. This study aimed to compare the environmental implications of co-digestion and mono-digestion of livestock manure (poultry and cow manure) with food waste from a life cycle assessment perspective for the regional context of Bangladesh. Two inventory cases were considered, accounting for mechanistically calculated (case M) and experimentally reported synergistic biogas yield (case E). Co-digestion scenarios showed net benefits by reducing three of the five impact categories-considerably reducing climate change (up to 117%), eutrophication potential, and terrestrial ecotoxicity in both cases (54.5 % and 55.7 %, respectively). The highest decrease occurred for climate change by diverting food waste landfilling. However, when synergistic biogas yield was considered, acidification potential and malodor air emissions increased by co-digestion owing to a higher amount of hydrogen sulfide and ammonia in the produced gas, thus entailing significant environmental burdens. The key hotspot in most categories was open storage of digestate, necessitating appropriate post-treatment. [ABSTRACT FROM AUTHOR]

Johne's disease (JD) control is often based on the culling of positive animals and the adoption of management practices that minimize exposure of young stock to the pathogen (Mycobacterium avium ssp. paratuberculosis). Throughout 2010 to 2013, the province of Ontario, Canada, instituted a voluntary Johne's control program consisting of whole-herd testing and risk assessment. The JD risk assessment evaluated 5 management areas to characterize herd JD risk. Using a modified milk ELISA technique with an optical density cut-off of 0.089, province-wide bulk tank milk (BTM) testing was used to assess the prevalence of JD high-risk herds at the end of the control program and again 4 yr after its completion. Approximately 71% of Ontario bulk tanks were classified as positive in 2017 compared with roughly 46% in 2013. In 2019, the same JD risk assessment used in the original program was readministered on 180 Ontario dairy farms. Using this cross-sectional approach, logistic regression models were built using data from the original program risk assessment and follow-up risk assessment as well as the BTM ELISA results to determine management factors associated with the control of JD. We demonstrated that management of the maternity area is an important factor in the control of Johne's disease. Although it is believed that the highest risk group for JD infection is calves under 6 mo, the cleanliness scores of older heifers and their exposure to mature cow manure was significantly associated with JD control; farms with highly contaminated weaned and bred heifers and those that had exposure to mature cow manure were more likely to be unsuccessful in their JD control efforts. Careful management of young calves appears to be important for JD control, and this management should continue even after calves have left the maternity area. [ABSTRACT FROM AUTHOR]

Composting is a common practice used for treating animal manures before they are used as organic fertilizers for crop production. Whether composting can effectively reduce microbial pathogens and antibiotic resistance genes remain poorly understood. In this study, we compared 3 different dairy manure composting methods—anaerobic fermentation (AF), static compost (SC), and organic fertilizer production (OFP)—for their effects on antibiotic-resistant bacteria, antibiotic resistance genes, and microbial community diversity in the treated manures. The 3 composting methods produced variable and distinct effects on antibiotic-resistant bacteria, zoonotic bacteria, and resistance genes, some of which were decreased and others of which showed no significant changes during composting. Particularly, SC and OFP reduced chloramphenicol resistance gene fexA and opportunistic pathogen Vibrio fluvialis , whereas AF significantly reduced tetracycline resistance gene tetB and opportunistic pathogens Enterococcus faecium and Escherichia fergusonii. The compositions of microbial communities varied significantly during the composting processes, and there were significant differences between the 3 composting methods. In all 3 composts, the dominant phyla were Firmicutes , Proteobacteria , Bacteroidetes , and Actinobacteria. Interestingly, Firmicutes , Proteobacteria , and Bacteroidetes remained stable in the entire AF process, whereas they were dominated at the beginning, decreased at the early stage of composting, and rebounded at the later stage during SC and OFP. In general, SC and OFP produced a more profound effect than AF on microbial community diversities, pathogens, and dominant species. Additionally, Enterococcus aquimarinus was isolated from AF for the first time. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States function prediction analysis indicated that the genes related to membrane transport and amino acid metabolism were abundant in the 3 composts. The metabolism of amino acids, lipids, and carbohydrates increased as composting progressed. The biosynthesis of antibiotics was enhanced after fermentation in the 3 composting methods, and the increase in the SC was the most obvious. These results reveal dynamic changes in antibiotic-resistant bacteria, antibiotic resistance genes, microbial community composition, and function succession in different dairy manure composts and provide useful information for further optimization of composting practices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-developed reactor improves the mass and heat transfer in AD process. • System operates stably at organic loading rate of 20 g VS/(L·d) with 1.55 L/(L·d). • Methane yield is best when the optimal spray time (9 times/d) is used in batch AD. • The processes of hydrolysis and acidification were enhanced. In this study, a new vertical plug-flow continuous dry anaerobic digestion reactor equipped with a spray percolation system was designed for rice straw and cow manure in dry AD. The findings indicated that the methane yield was 290.63 ± 19.16 mL/g VS when the optimal spray time (9 times/d) was used in batch AD. In addition, the results of continuous experiments under optimal spray time conditions showed that the volumetric methane production rate of the system was 1.55 L/(L·d) when the organic loading rate was 20 g VS/(L·d). In addition, hydrolysis and acidification steps were enhanced. This study demonstrated the potential of the new reactor for stable operation of high OLR dry AD. Digestate is already used as a substitute for synthetic fertilizers precisely because of the environmental benefits associated with its agronomic use. [ABSTRACT FROM AUTHOR]

[Display omitted] • A cryolithophilic thermophilic nitrifying bacterial consortium (CNB) was developed. • CNB enhanced nitrite oxidoreductase's activity and elevated nxrA gene abundance. • CNB inoculation reduced NH 3 and N 2 O emissions and increased the humus content. • CNB inoculation of compost is environmentally friendly and cost-effective. Excessive nitrogen release during composting poses significant challenges to both the environment and compost quality. Biological enhancement of humification and nitrogen conservation is an environmentally friendly and cost-effective approach to composting. The aim of this study was to develop a psychrophilic and thermophilic nitrifying bacterial consortium (CNB) and investigate its role in nitrogen transformation and humification during cow manure composting. Analysis revealed that CNB inoculation promoted microbial proliferation and metabolism, significantly increased the number of nitrifying bacteria (p < 0.05), and elevated the activity of nitrite oxidoreductase and nxrA gene abundance. Compared to the control, CNB inoculation promoted the formation of NO 3 –-N (77.87–82.35 %), while reducing NH 3 (48.89 %) and N 2 O (20.05 %) emissions, and increased humus content (16.22 %). Mantel analysis showed that the higher abundance of nitrifying bacteria and nxrA facilitated the nitrification of NH 4 +-N. The improvement in nitrite oxidoreductase activity promoted NO 3 –-N formation, leading to increased humus content and enhanced compost safety. [ABSTRACT FROM AUTHOR]

[Display omitted] • Crucial impact of initial C/N on compost process confirmed through meta -analysis. • Recommended initial C/N for pig and chicken manure composting are 20–25. • Recommended initial C/N for sheep and cow manure composting are 25–35. • Extended durations are necessary for composting at high initial C/N ratios. • Use of microbial inoculants recommended for enhancing composting at low initial C/N. Given the heterogeneity of raw materials, the diversity of composting processes, and the complexity of biological transformations, systematically exploring the critical role of the initial carbon-to-nitrogen (C/N) ratio in the aerobic composting of agricultural residues is challenging within a single experimental study. This study employs meta -analysis to investigate this role. Statistical analysis of 192 scholarly articles confirmed that most studies adhere to the recommended optimal initial C/N range of 25 and 30, where enhanced compost maturity and nutrient accumulation are observed. The findings indicate that optimal initial C/N ratios vary by agricultural residue type. A C/N ratio of 20 to 30 facilitates controlling the composting duration within 45 days, while a C/N ratio of 30 to 35 necessitates extending the duration beyond 45 days. The study highlights the effectiveness of adjusting the C/N ratio and applying microbial inoculants and physical amendments to optimize composting outcomes and control the composting duration. [ABSTRACT FROM AUTHOR]

Protecting soil organic compounds could assist with global efforts to mitigate climate change, as well as improve soil health. Recent research has indicated that high surface area inorganic minerals (HSAIMs) can protect soil organic matter (OM). We evaluated if adding HSAIMs to soils can protect carbon from common organic inputs added to fallow soils prior to planting. Four added HSAIMs were investigated – two manufactured zeolites, one natural zeolite and bentonite clay – along with a carbon-rich (peat moss) and carbon-poor (composted cow manure) OM source. The added HSAIMs and organic sources were incorporated into a microbially active (clayey Vertisol) and inactive (sandy Arenosol) soil at application rates of 20 tonnes.ha–1 for the minerals and 60 tonnes.ha–1 for the organics. The treatments were incubated for three months under laboratory conditions and were subjected to continuous wetting-drying cycles. Peat moss resulted in higher organic carbon (C org) and OM losses than cow manure. Moreover, the addition of HSAIMs to the Peat Moss+Arenosol treatments appeared to slightly enhance these losses, albeit not significantly (p>0.05). Carbon/nitrogen (C/N) ratios revealed that the Arenosol treatments were depleting soil N to access the carbon provided by the peat moss. For all other treatment combinations, the addition of HSAIMs promoted greater retention of C org (p<0.05 in one treatment combination) and OM (p<0.05 in four treatment combinations), relative to the controls. Modelling carbon balances using OM data was more effective than using direct C org values, due to strong C org measurement variance. Modelled C org data revealed the added HSAIMs achieved up to 25 % carbon protection, with the manufactured zeolites particularly effective. The study shows promise for added HSAIMs to protect carbon released from decomposing organic amendments added to fallow soils. However, addition of these minerals to N-limited soils receiving carbon-rich amendments might accelerate carbon losses. • High surface area inorganic minerals generally protected carbon from soil organic amendments. • However, in N-poor soils they can accelerate carbon loss. • Modelling soil organic carbon using organic matter data can improve measurement precision. • Field testing of the approach is recommended. [ABSTRACT FROM AUTHOR]

Soil salinization poses a global challenge, and cultivating rice on saline-alkali lands is a recognized strategy for exploiting and ameliorating these challenging environments, however, the yield and quality of rice are significantly lower compared to cultivation on non-saline lands. This study focused on the utilization of saline-alkali tolerant plant-growth-promoting microorganisms (PGPRs) and organic matter. Four PGPR strains were identified and subsequently fermented and propagated, and then combined in equal proportions and mixed with cow manure compost to prepare a PGPR amendment. This amendment was applied to rice cultivated in pots under saline-alkali stress. Agronomic traits were monitored at various growth stages to assess the amendment's impact on rice development. The results showed that under moderate saline-alkali stress, PGPR amendments significantly improved the physicochemical indicators of rice. Compared with the control group, rice plant height, root length and chlorophyll content increased by 113.56%, 43.19% and 95.43%, respectively. The antioxidant enzyme increased by 39.86%, and the levels of soluble sugars and proteins increased by 20.91% and 27.28%, respectively. Notably, rice under moderate saline-alkali stress showed greater improvements in response to the amendment compared to rice under mild stress conditions. These findings suggest that the amendments effectively mitigate the adverse effects of saline-alkali stress on rice growth, thereby offering a viable strategy for enhancing crop productivity in affected areas. [Display omitted] • Four strains of saline-alkali tolerant PGPR were isolated. • Rice growth was inhibited by varying degrees of saline-alkali stress. • Integrating PGPR with organic substrates avoided the limitations of individual use. • The application of PGPR amendment alleviated stress and increased rice biomass. • The synergy between PGPR and cow dung promoted rice development in saline soils. [ABSTRACT FROM AUTHOR]

With the increasing use of plastic products globally, environmental pollution by plastic waste is becoming increasingly problematic. This study investigated the impacts of two types of polylactic acid microplastics, clear microplastics and aluminised film microplastics, on methane yield, microbial community, and volatile fatty acid accumulation during anaerobic co-digestion of cow manure and Chinese cabbage waste under different temperature conditions. The influence of the addition of air nanobubbles on microplastic degradation in the anaerobic digestion system we also examined. The results revealed that under thermophilic conditions, clear and aluminised film microplastics increased the methane yield, with the latter resulting in greater improvement. Conversely, under mesophilic conditions, the presence of microplastics reduced the methane yield, but the addition of air-nanobubble partially mitigated this effect. Microplastics also affected the microbial community, with specific species showing correlations with methane yield. Methanothermobacter , which is linked to lactic acid conversion, was positively correlated with methane yield, whereas Methanomassiliicoccus levels increased in the presence of microplastics, particularly in the inhibited state of the digester. These results suggest that, under thermophilic conditions, microplastics may increase the cumulative methane yield by facilitating the degradation of lactic acid monomers. Furthermore, the aluminised film on microplastics could serve as an electrically conductive material during anaerobic digestion, potentially increasing the methane yield. [Display omitted] • PLA promoted AD in thermophilic condition with a 6.2–18.3% increase in methane yield. • PLA was resistant to mesophilic AD and decreased methane yield. • Aluminised film acted as a conductive material in thermophilic AD. • Added air-NBW to PLA-added digesters can increase methane yield by 12.5–15.1%. • Methanothermobacter was highest in the whole AD process when PLA and NBW were added. [ABSTRACT FROM AUTHOR]

Fertilization exerts a profound influence on the formation, turnover and stabilization of soil organic carbon (SOC). However, how long-term fertilization regulates the contribution of plant residues and microbial necromass to SOC sequestration in acidic paddy soil remains unclear. This study aimed to elucidate these mechanisms by determining plant and microbial biomarkers, i.e., lignin phenols and amino sugars, as well as carbon degradation genes in both topsoil (0–15 cm) and subsoil (15–30 cm) within the context of a 10-year paddy field experiment. We investigated four fertilization regimes: no fertilizers (control), chemical fertilizers applied alone (NPK), NPK combined with cattle manure (NPKM), and NPK combined with rice straw (NPKS). Compared to the control, integrated organic-inorganic fertilization increased SOC by 15–21 % and 14–19 % in the topsoil and subsoil, respectively. Specifically, NPKM and NPKS did not alter the contribution of total lignin phenols to SOC in the topsoil but increased that in the subsoil by 63 % and 26 %, respectively. SOC accumulation exhibited a positive correlation with the concentration of total lignin phenols but a negative correlation with the acid to aldehyde ratio of vanillyl, indicating selective preservation of vanillyls. However, NPKM and NPKS decreased the contribution of total microbial residual carbon (MRC) to SOC in the topsoil (13–16 %) but didn't alter that in the subsoil. The decreased MRC contribution of topsoil was mainly reflected in fungal MRC, implying that fungi played a pivotal role in regulating topsoil carbon accumulation. Correlation analyses indicated that soil biotic and abiotic factors jointly affected the sequestration of plant lignin phenols and microbial necromass, and topsoil carbon accumulated with the abundance ratio of hydrolytic to oxidative enzyme-coding genes increasing (r = 0.62, p < 0.05). Combined with Partial Least Squares Path Model, our study revealed that the accumulation of organic carbon in the topsoil was more influenced by plant-derived carbon, whereas in the subsoil, it was co-affected by both plant- and microbially-derived carbon. • Topsoil OC accumulated with the abundance ratio of hydrolytic to oxidative enzyme coding genes increasing; • Organic amendments decreased microbially-derived C to topsoil OC but increased plant-derived C to subsoil OC; • Soil abiotic and biotic factors jointly affected the accumulation of plant- or microbially-derived C; • Topsoil OC was more influenced by plant-derived C, while plant- and microbially-derived C co-affected subsoil OC. [ABSTRACT FROM AUTHOR]

This study examined the impact of different biochar (BC) as an anaerobic digestion (AD) additive on antibiotic-resistant bacteria (ARB) survival and AD performance using dairy cow manure. Bamboo BC and Olive BC with different particle sizes were added into the mesophilic AD at 15 g/L and 30 g/L dosages (Bamboo-15, Bamboo-30, Olive-15, and Olive-30). The study provides a detailed analysis of biogas production, organic metabolism, and ARB and microbial dynamics, elucidating the mechanisms by which BC influences AD. Findings reveal significant reductions in CEZ-resistant bacteria (CEZ-r) across all reactors, ranging from 12.88 % to 76.47 %. Both Bamboo and Olive BC increased CEZ-r removal by 3.08–5.94 times compared to the control. Additionally, BC supplementation prevented the rise in CEZ-r percentage within the total bacteria count observed in the control reactor. Bamboo BC outperformed Olive BC in enhancing biogas yield, with Bamboo-15 and Bamboo-30 showing significant increases of 43.2 % and 48.0 %, respectively, compared to the control. Adding BC in AD regulates ARB by decreasing potential ARG hosts and impeding the transmission of resistance. It also enhances biogas production by improving the efficiency of methanogenic bacteria and optimizing the methanogenic pathway. This research provides insights into how BC can be used to enhance AD performance and mitigate ARB proliferation, offering a sustainable approach to waste management and energy production. • Bamboo biochar showed a better antibiotic-resistant bacteria (ARB) removal and digestion performance. • The dosage of 15 g/L biochar was better than 30 g/L in ARB reduction. • Olive biochar was more effective in reducing the abundance of ARG host bacteria. • Bamboo biochar might control ARB by ARG absorption and destruction. • Bamboo biochar might improve DIET and enrich the biogas production pathway. [ABSTRACT FROM AUTHOR]

• Biochar from cow manure synthesized at various pyrolysis temperatures. • CMBC900 shows superior adsorption capacities for MB (200 mg/g) and MO (147 mg/g). • Functional groups like -COOH, C = O, and -OH are crucial in dye adsorption. • CMBC900 maintains high efficiency after ten adsorption-desorption cycles. • Converting agricultural waste to biochar offers economic and environmental benefits. This study investigates the synthesis of biochar from cow manure at various pyrolysis temperatures and its effectiveness in dye adsorption, focusing on how temperature influences the adsorption capacities of biochar towards MB and MO. Biochar was produced at four pyrolysis temperatures (300, 500, 700, and 900 °C), labeled CMBC-x. Adsorption capacities for MB and MO were tested. Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) identified functional groups involved in dye adsorption. Biochar produced at 900 °C (CMBC900) showed the highest adsorption capacities: 200 mg g-1 for MB and 147 mg g-1 for MO. For a dye mixture, CMBC900 adsorbed 104.5 mg g-1 of MB and 98.7 mg g-1 of MO, indicating efficient separation. CMBC900 maintained high efficiency after ten cycles, with 97.5 % for MB and 90.5 % for MO. These findings highlight the robustness and long-term potential of CMBC900 as an adsorbent. Converting agricultural waste into biochar offers an economically viable solution for waste management and environmental protection by removing harmful dyes from wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

This study investigated the thermochemical conversion of cattle manure (CM) to propose a sustainable platform for its valorization, and explored the applicability of CM-derived biochar (CMB) as an environmental medium for the adsorptive removal of sulfamethoxazole (SMZ). CM pyrolysis was conducted under two atmospheric conditions (N 2 and CO 2), and the pyrogenic products were quantified and characterized. Real-time syngas monitoring revealed that CO 2 enhanced CO generation from the CM, leading to the formation of a highly porous carbon structure in the produced biochar (CMBCO 2). The adsorptive removal of SMZ by CMBCO 2 was highly dependent on the pH conditions. The adsorption kinetics of SMZ onto CMBCO 2 reached equilibrium within 540 min, following a pseudo-second-order model. The SMZ adsorption isotherms fit the Langmuir-Freundlich model, highlighting the importance of chemisorption in the adsorption process. X-ray photoelectron spectroscopy revealed that SMZ was adsorbed by non-electrostatic mechanisms, including hydrogen bonding, Lewis acid-base interactions, surface complexation, and π–π electron-donor acceptor interactions. This study presents an exemplary strategy for converting livestock waste into valuable resources, enabling the harvesting of energy resources and the production of treatment media for environmental remediation. [Display omitted] • Livestock waste (cattle manure, CM) was pyrolyzed in the N 2 and CO 2 conditions. • The use of CO 2 led to the production of enhanced syngas (CO) and porous biochar. • Biochar (CMBCO 2) exhibited high adsorption capacity for sulfamethoxazole (SMZ). • SMZ was chemisorbed by non-electrostatic reactions to adsorption sites in CMBCO 2. [ABSTRACT FROM AUTHOR]