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Pyrolysis of animal manure at high temperature is necessary to effectively immobilize heavy metals, while the available phosphorus (P) level in biochar is relatively low, rendering it unsuitable for use as fertilizer. In this study, the pretreatment of swine manure with different potassium (K) sources (KOH, K2CO3, CH3COOK and C6H5K3O7) was conducted to produce a biochar with enhanced P availability and heavy metals immobility. The addition of all K compounds lowered the peak temperature of decomposition of cellulose in swine manure. The percentage of ammonium citrate and formic acid extractable P in biochar increased with K addition compared to undoped biochar, with CH3COOK and C6H5K3O7 showing greater effectiveness than KOH and K2CO3, however, water- extractable P did not exhibit significant changes. Additionally, the available and dissolved Si increased due to the doping of K, with KOH and K2CO3 having a stronger effect than CH3COOK and C6H5K3O7. X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) analysis revealed that K addition led to the formation of soluble CaKPO4 and silicate. In addition, the incorporation of K promoted the transformation of labile copper (Cu) and znic (Zn) into the stable fraction while simultaneously reducing their environmental risk. Our study suggest that the co-pyrolysis of swine manure and organic K represents an effective and valuable method for producing biochar with optimized P availability and heavy metals immobility. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board 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.)

Manure application is a recommended method to improve soil quality and mitigate global warming via soil carbon (C) sequestration. However, such application can significantly increase ammonia (NH3) volatilization loss and cause secondary environmental problems, such as acidification, eutrophication, and particulate matter formation. To investigate the potential of reducing NH3 emissions in flooded rice paddies, three types of stabilized swine manure amendments (fresh, composted, and biochar) were applied at a rate of 12 Mg ha-1 (dry weight) under standard fertilization (N-P2O5-K2O = 90-45-57 kg ha-1), and NH3 emission was characterized using the static chamber method. Regardless of manure management practices, NH3 fluxes increased significantly immediately after application of an inorganic nitrogen (N) fertilizer (urea). The manure was applied completely as the basal fertilizer before rice transplanting, but the NH3 emission rates increased more dramatically following urea application in the manure treatments. Fresh and composted manure applications significantly increased seasonal NH3 volatilization losses compared to the control but the biochar did not. Compost manure significantly increased rice grain productivity owing to the higher N content, while fresh and biochar manures did not increase rice productivity because of fewer panicles per hill and fewer grains per panicle. Consequently, biochar application resulted in lower NH3 flux intensity and seasonal NH3 flux per grain yield, whereas fresh and compost manures substantially increased this intensity. Therefore, biochar manure may be a more reasonable organic amendment than fresh and composted manures for reducing NH3 emission impacts on rice paddies. [ABSTRACT FROM AUTHOR]

Livestock manure and crop residues are significant sources of phosphorus. However, the ineffectiveness of current processing technologies often leads to the suboptimal recovery of this phosphorus, causing considerable resource wastage and environmental pollution. Recently, global research has increasingly been focused on the resource recovery of organic waste materials using hydrothermal carbonization technology. This study investigated variations in phosphorus forms in the hydrochar produced from swine manure and rice straw, employing diverse hydrothermal carbonization conditions and applying the Box–Behnken response surface methodology and Hedley's phosphorus fractionation method. The results indicated that inorganic phosphorus predominates in the hydrochar, with organic phosphorus comprising 5–30% of the total phosphorus. Furthermore, the study found that the available phosphorus content, as measured by NaHCO3 extraction, decreased as the reaction time and temperature of the hydrothermal carbonization process increased. The concentrations of H2O-P and NaHCO3-P fractions decreased with increasing reaction times and temperatures but increased with a higher swine manure-to-straw ratio. Conversely, the concentrations of NaOH-P and HCl-P fractions showed an increasing trend with rising reaction temperature, prolonging reaction time, andusing a high swine manure-to-straw ratio. Consequently, this study offers vital theoretical and practical insights into the resource utilization of livestock manure and crop straw, significantly contributing to the challenges of waste management and environmental sustainability in agriculture. [ABSTRACT FROM AUTHOR]

Black soldier fly larvae (BSFL) treatment offers a promising avenue for manure valorization. However, there is a lack of larval density studies and ton-scale exploration in swine manure bioconversion. This study delves into the efficiency of larval fatty acid (FA) bioconversion, examining the impact of larval density on a kilogram scale and extending the analysis to a ton scale. Across a range of 50 to 600 larvae/kg, the larval FA content decreased from 15.3% to 7.85%. The peak larval FA yield, at 3.04% (based on manure dry matter), occurred at a density of 200 larvae/kg. Both low (50 larvae/kg) and high (600 larvae/kg) densities adversely affected BSFL bioconversion performance. Dominant larval FAs included C12:0 (39.7%), C16:1 (24.2%), C18:1 (17.5%), and C16:0 (8.3%). The scaling-up process maintained a consistent larval FA content and composition but resulted in decreased larvae FA yield due to increased larval mortality. Ultimately, each ton of swine manure yielded 12.4 kg of fresh larvae or 0.71 kg of larval FA components, corresponding to a 1.14% larval FA yield. This study underscores the feasibility of upscaling swine manure treatment using BSFL for FA bioconversion and emphasizes the necessity for large-scale studies to enhance larval survivorship and bioconversion efficiency.

Abstract Pyrolysis of animal manure at high temperature is necessary to effectively immobilize heavy metals, while the available phosphorus (P) level in biochar is relatively low, rendering it unsuitable for use as fertilizer. In this study, the pretreatment of swine manure with different potassium (K) sources (KOH, K2CO3, CH3COOK and C6H5K3O7) was conducted to produce a biochar with enhanced P availability and heavy metals immobility. The addition of all K compounds lowered the peak temperature of decomposition of cellulose in swine manure. The percentage of ammonium citrate and formic acid extractable P in biochar increased with K addition compared to undoped biochar, with CH3COOK and C6H5K3O7 showing greater effectiveness than KOH and K2CO3, however, water- extractable P did not exhibit significant changes. Additionally, the available and dissolved Si increased due to the doping of K, with KOH and K2CO3 having a stronger effect than CH3COOK and C6H5K3O7. X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) analysis revealed that K addition led to the formation of soluble CaKPO4 and silicate. In addition, the incorporation of K promoted the transformation of labile copper (Cu) and znic (Zn) into the stable fraction while simultaneously reducing their environmental risk. Our study suggest that the co-pyrolysis of swine manure and organic K represents an effective and valuable method for producing biochar with optimized P availability and heavy metals immobility.

In anaerobic digestion (AD) processes, hydrolysis is considered the limiting stage in the degradation of solid wastes. Such is the case of swine manure digestion, which due to the complex physical and chemical structure of the lignocellulosic material that composes it, an energy wastage has been observed in terms of methane production. Among the strategies used to improve the hydrolysis stage, it is possible to mention the thermal pretreatment of the substrate, which can significantly improve the biodegradability of the material used as raw material in AD. In this study, the effect of temperature (60-177 °C) and exposure time (30-60 min) on the physicochemical properties of the substrate such as pH, volatile organic acids (VOAs), total inorganic carbonates (TIC), volatile solids (SV), total solids (ST), soluble chemical oxygen demand (CODs) and biochemical methane potential (BMP) were determined. The temperature factor had a higher level of significance compared to the exposure time on the parameters of pH, VOAs, and TIC before and after the biogas generation process. However, the effect was different for CODs, where time was more significant than treatment temperature. As for the parameters of total and volatile solids content (ST and SV), the factors evaluated (temperature and exposure time) did not show significant effect. Also, the pretreatments showed an increase in biochemical methane potential, outperforming the untreated substrate by up to 70.4 % (121.74vs.71.44 mLCH4 gVS-1). The best combination of heating temperature and operating time was 120 °C and 45 min, which promoted the hydrolysis step that was reflected in an increase in CODs and improvement in methane production by 42 % over the untreated substrate. [ABSTRACT FROM AUTHOR]

Purpose: Clean and efficient alternatives for sustainable treatment of pig farming wastes are a priority in suburban areas in Forest Reserves of High Andean ecosystems. Among these technologies are Bokashi Fermentation and composting with added microorganisms (bioaugmentation) or nutrients (biostimulation) as biological activators. Method: In a Colombian rural area located at 3160 m.a.s.l., focused on small-scale swine production, Bokashi fermentation with active dry yeast and in-vessel composting were evaluated using two microbial inoculants and a sterile metabolic stimulant. In addition, these treatments were compared with a non-inoculated composting process used in the study area (control). Results: The biological additives improved the composting process performance and end-product quality by shortening the degradation cycle (19.9−45.9%), higher germination index (> 0.8%), increasing nutrient content (N, P, S, Fe and Cu) and showing suppressive activity against Fusarium oxysporum compared to control. Nevertheless, Bokashi was the only treatment that decreased Enterobacteriaceae concentration below 1E+03 CFU g−1. Conclusion: Bokashi technology complies with Colombia’s environmental regulations for eco-friendly fertilizer production, which allows the sustainable management by-products from swine activities in critical ecological areas such as Forestry Protection Reserves in High Andean ecosystems. [ABSTRACT FROM AUTHOR]

Hydrothermal carbonization (HTC) is a promising technology for wet manure treatment by converting animal manure into valuable fuels, materials, and chemicals. Among other HTC process parameters, the temperature influences HTC products the most. As various animal manures have different compositions, it is not certain how the HTC temperature influences the hydrochar and HTC process liquid. To evaluate the temperature's effect on HTC, three different manures (poultry, swine, and dairy) were hydrothermally carbonized at three different temperatures (180, 220, and 260 °C), and solid and liquid products were characterized for their morphology, elemental compositions, and ions. The carbon contents of the hydrochar reached as high as 38.98 ± 0.36% and 40.05 ± 0.57% for poultry and swine manure, respectively, when these manures were treated at 260 °C. Ammonium showed an around 30% increase in poultry manure hydrochar with the increase in the HTC temperature. In contrast, in swine manure, it decreased by around 80%, and in dairy manure, the HTC temperature did not have any remarkable effect on the ammonium content. The process liquids from HTC of dairy manure at 220 °C showed the most balanced distribution of different ions, with 4970 ± 673 ppm of sodium, 4354 ± 437 ppm of ammonium, 2766 ± 417 ppm of potassium, 978 ± 82 ppm of magnesium, 953 ± 143 ppm of calcium, 3607 ± 16 ppm of chloride, and 39 ± 7 ppm of phosphate. These results emphasize the manure-specific effects of the HTC temperature on both solid and liquid products, indicating the need for optimized strategies to enhance HTC processes for various types of animal manures. [ABSTRACT FROM AUTHOR]

The problem of antibiotic resistance genes (ARGs) caused by heavy metals has attracted extensive attention of human beings. Zn, a widely used feed additive, has a very high residue in swine manure, but the distribution characteristics of ARGs imposed by Zn in anaerobic digestion (AD) products are not clear. In this study, the behaviour of mobile genetic elements (MGEs), bacterial community, and their association with ARGs were determined in the presence of 125 and 1250 mg L–1 Zn in AD system of swine manure. Zn-treated enriched the abundance of ARGs, and produced some new genotypes that were not detected in CK treatment. In addition, low concentration of Zn significantly increased the relative abundance of ARGs, as compared to higher Zn and CK group. Correspondingly, the abundances of most top30 genus were highest in ZnL (125 mg L–1 Zn), followed by CK and ZnH (1250 mg L–1 Zn). Notably, network analysis showed that the relationship between ARGs and MGEs is closer than that ARGs and bacteria, suggesting that ARGs increased in Zn-treated, especially low level Zn, may be due to the amplification transfer of ARGs among varied microorganisms by horizontal transfer with MGEs. Therefore, strengthen the management of in livestock manure is crucial to control the spread of ARGs in organic fertilizers. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigates the impact of iron oxide (Fe3O4) nanoparticles on the anaerobic digestion (AD) of frass, a by-product of black soldier fly (BSF) larvae bioconversion of swine manure, and its co-digestion with corn straw. The aim is to enhance biogas production, particularly during the inoculum-free start-up phase of the AD process. Results indicate that the incorporation of Fe3O4 nanoparticles, especially those of ~184 nm size, significantly boosts average biogas yields, with a notable increase in methane production compared to control groups. The methanogenic analysis reveals that species such as Methanocorpusculum, Methanosarcina, and Methanomassiliicoccus play crucial roles in the AD reactor, with the ~184 nm group demonstrating optimal microbial diversity, potentially accounting for its superior gas output. The findings contribute to the advancement of renewable energy generation, sustainable development, and environmental conservation by providing a scientific basis for improving the efficiency of biogas production from organic waste. With the increasing prominence of the global energy problem, socioeconomic activities have been seriously affected. Biofuels, as a renewable source of energy, are of great significance in promoting sustainable development. In this study, batch anaerobic digestion (AD) of frass (swine manure after bioconversion by black soldier fly larvae) and co-digestion with corn straw after the addition of iron oxide (Fe3O4) nanoparticles is investigated, as well as the start-up period without inoculation. The biochemical methane potential of pure frass was obtained using blank 1 group and after the addition of various sizes of Fe3O4 nanoparticles for 30 days period, and similarly, the digestion of frass with straw (blank 2) and after the addition of various sizes of Fe3O4 nanoparticles for 61 days period. The results showed that the average gas production was 209.43 mL/gVS, 197.68 mL/gVS, 151.85 mL/gVS, and 238.15 mL/gVS for the blank, ~176 nm, ~164 nm, and ~184 nm, respectively. The average gas production of frass with straw (blank 2) was 261.64 mL/gVS, 259.62 mL/gVS, 241.51 mL/gVS, and 285.98 mL/gVS for blank 2, ~176 nm, ~164 nm, and ~184 nm, respectively. Meanwhile, the accumulated methane production of the ~184 nm group was 2312.98 mL and 10,952.96 mL, respectively, which significantly increased the biogas production compared to the other groups. The methanogenic results of the frass (30 days) indicated that Methanocorpusculum, Methanosarcina, and Methanomassiliicoccus are the important methanogenic species in the AD reactor, while the microbial diversity of the ~184 nm group was optimal, which may be the reason for the high gas production of ~184 nm. [ABSTRACT FROM AUTHOR]

Anaerobic digestion of animal manure generates biogas and removes biodegradable organic matter, while most of the nitrogen and phosphorous remains at very high levels after the process. A subsequent microalgae culture in the digestate provides nutrient uptake at very low operational and installation costs. However, the dark color of manure digestate prevents light penetration, reducing the rates of algae growth. Ozonation was researched as a strategy for color removal followed by microalgae culture. Although similar biomass production was achieved in treated and untreated digestates (1.09 vs. 0.99 g L−1), the positive effect of ozonation was evidenced by the significantly higher rates of photosynthetically produced oxygen: 0.804 and 0.18 mg O2 mg−1 TSS min−1, respectively, in ozonated and untreated digestates, revealing a four times higher rate of algae activity. However, this considerable higher activity was not correlated with better performance in nutrient removal since the microalgae treatment was assayed at a considerably reduced scale with a high ratio of illumination per volume. An operational costs analysis revealed that ozonation could be competitive against other strategies of color reduction such as dilution or coagulation/flocculation processes. [ABSTRACT FROM AUTHOR]

Escherichia coli is one of the key bacteria responsible for a variety of diseases in humans and livestock-associated infections around the globe. It is the leading cause of mortality in neonatal and weaned piglets in pig husbandry, causing diarrhea and significant harm to the industry. Furthermore, the frequent and intensive use of antimicrobials for the prevention of diseases, particularly gastrointestinal diseases, may promote the selection of multidrug-resistant (MDR) strains. These resistant genotypes can be transmitted through the excrement of animals, including swine. It is common practice to use porcine manure processed by biodigesters as fertilizer. This study aimed to examine the antimicrobial susceptibility, the presence of virulence genes frequently associated with pathotypes of intestinal pathogenic E. coli (InPEC), and antimicrobial resistance genes (ARGs) of 28 E. coli isolates collected from swine manure fertilizers. In addition, the enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) technique was used to investigate the genetic relationship among the strains. Using disk diffusion, the antimicrobial susceptibility profiles of the strains were determined. Using polymerase chain reaction (PCR), 14 distinct virulence genes associated with the most prevalent diarrhea and intestinal pathogenic E. coli (DEC/InPEC) and five ARGs were analyzed. All isolates tested positive for multidrug resistance. There was no detection of any of the 14 virulence genes associated with InPECs, indicating the presence of an avirulent commensal microbiota. Molecular classification by ERIC-PCR revealed that the majority of isolates (27 isolates) coalesced into a larger cluster with a genetic similarity of 47.7%; only one strain did not cluster in this cluster, indicating a high level of genetic diversity among the analyzed isolates. Thus, it is of the utmost importance to conduct epidemiological surveillance of animal breeding facilities in order to determine their microbiota and formulate plans to reduce the use of antimicrobials and improve animal welfare. [ABSTRACT FROM AUTHOR]

Freshwater environments are primary receiving systems of wastewater and effluents, which carry low concentrations of antibiotics and antimicrobial-resistant (AMR) bacteria and genes. Aquatic microbial communities are thus exposed to environmentally relevant concentrations of antibiotics (ERCA) that presumably influence the acquisition and spread of environmental AMR. Here, we analyzed ERCA exposure with and without the additional presence of municipal wastewater treatment plant effluent (W) and swine manure run-off (M) on aquatic biofilm resistomes. Microscopic analyses revealed decreased taxonomic diversity and biofilm structural integrity, while metagenomic analysis revealed an increased abundance of resistance, virulence, and mobile element-related genes at the highest ERCA exposure levels, with less notable impacts observed when solely exposed to W or M effluents. Microbial function predictions indicated increased gene abundance associated with energy and cell membrane metabolism and heavy metal resistance under ERCA conditions. In silico predictions of increased resistance mechanisms did not correlate with observed phenotypic resistance patterns when whole communities were exposed to antimicrobial susceptibility testing. This reveals important insight into the complexity of whole-community coordination of physical and genetic responses to selective pressures. Lastly, the environmental AMR risk assessment of metagenomic data revealed a higher risk score for biofilms grown at sub-MIC antibiotic conditions. [ABSTRACT FROM AUTHOR]

To predict the mineralization of nitrogen(N) in organic amendments in paddy fields, we applied data obtained from incubation experiments under waterlogged conditions by a hierarchical Bayesian model using acid-detergent-soluble organic N (ADSON) as a model input. Each of 20 organic amendments (6 cattle manure composts, 3 swine manure composts, 3 poultry manure composts, 2 oil cakes, 2 rice brans, 1 fish meal, 1 sludge fertilizer, and 2 mixed commercial organic fertilizers) was mixed with paddy soil, and the N mineralization curves obtained after 1, 2, 4, 8, and 12 weeks of waterlogging were incorporated into the model to obtain values of the model parameters ki, α1, and Q10. All model parameters converged with a mean absolute error (MAE) of 0.044 g N kg−1, a root mean square error (RMSE) of 0.060 g N kg−1, and a model efficiency (EF) of 0.96. These values were comparable to or slightly better than those of a previous model for upland soil conditions. Most of the observed values were within the 95% Bayesian prediction interval, indicating that the model performed well with the observed data. Although it is generally believed that livestock manure composts decompose more slowly than organic fertilizers such as oil cake, the livestock manure composts had a large value of the rate constant ki, presumably because of the initial rapid decomposition of the small amounts of organic N present in them. In paddy fields, the soil conditions are aerobic between the application of organic amendments and water entry. In such a case, we propose the use of the upland field model to predict the mineralization of organic N during the period of aerobic soil conditions and of this study's model during the period of waterlogging, subtracting the amount of already mineralized N from the parameters Nin and ADSON. The model devised here is expected to be useful for fertilization design in organic agriculture and in the reduction of the use of inorganic fertilizer. [ABSTRACT FROM AUTHOR]

To meet Colombia's energy needs by 2050, a total installed capacity of 42 MW across its power generation infrastructure is required. To achieve this, transitioning to cleaner energy sources, such as biomass—a non-conventional renewable energy—is necessary. Biomass is a promising renewable source for thermal and electrical energy production. This study researched the production of biogas from swine manure using a UASB reactor to valorize this waste. Swine manure was collected every 20 days from a pig farm with a capacity of 200 sows, located in Santa Rosa de Osos, Antioquia. The flow rate was increased three times (1.30 L d−1, 1.62 L d−1, and 2.08 L d−1) to reduce the hydraulic retention time (HRT) and enhance biogas production. The volatile and total solids, chemical oxygen demand (COD), alkalinity, and biogas composition were measured over one year. The proposed system achieved 87.40% COD remotion from the feed stream and generated a yield of 507 mLCH4 gVS−1, with an HRT of 19 days and an OLR of 4.27 gCOD L−1 d−1. The reactor produced biogas with a CH4 content of 67.7%, CO2 content of 18.1%, and H2S content of 1413 ppm. This study highlights the effectiveness of the UASB reactor for biogas production using swine manure as a substrate. [ABSTRACT FROM AUTHOR]

The anaerobic digestion process (AD) occurs via series of biochemical reactions, producing biogas as a renewable fuel and digestate, a rich by-product in trace elements (TEs), which has been directly disposed on soils as organic fertilizer. The application of mineral additives can result higher biogas production and CH4 yields in AD process; however, the chronical effects of these additives in digestates have not been reported in the literature. In this way, this research aims to analyze the chronic effects of digestates from swine manure (SD) and swine manure with iron ore tailings as additive (SDIOT) on survival and reproduction of Enchytraeus crypticus. The fresh samples were collected from sequential batch processes conducted at mesophilic conditions. The TEs and pH ranges in feedstock and digestates were determined in fresh matter (mg L−1), including analyses of heavy metals and nutrients, in which ranges concentrations were discussed according to biogas and CH4 productions, and compared with previous data of literature. These analyses were followed by chronic tests of digestates on reproduction of E. crypticus in Oxisols, in which tests performance met the validity criteria stablished according to ISO 16387 standard. The means of treatments were compared using the Holm–Sidak method, and the means of control groups were compared using t test (α = 0.05). The chronic effect on survival and reproduction of organisms might have occurred through synergistic effect of metals in digestates; however, more analyses must be needed to understand the toxicity effect of these products, specially under different climate conditions. Article Highlights: The application of swine manure resulted in a chronic effect to Enchytraeus crypticus. The synergistic effect of metals might have effects on organisms survival. Available fractions of metals and chemical properties of soils must also be evaluated. Climate change might influence on the speciation of metals within the soils. [ABSTRACT FROM AUTHOR]

Aims Understanding the inhibitory effects of natural organic substances on soil-borne pathogenic fungi and the relevant molecular mechanisms are highly important for future development of green prevention and control technology against soil-borne diseases. Our study elucidates the inhibitory effect of the combined application of humic acids (HAs) and chitosan on Alternariasolani and the light on the corresponding mechanism. Methods and Results The effect on A. solani growth by HAs incorporated with chitosan was investigated by plate culture and the corresponding mechanism was revealed using transcriptomics. The colony growth of A. solani was suppressed with the highest inhibition rate 33.33% when swine manure HAs was compounded with chitosan at a ratio of 1:4. Chitosan changed the colony morphology from round to irregularly. RNA-seq in the HAs and chitosan (HC) treatment revealed 239 differentially expressed genes compared with the control. The unigenes associated with enzymes activities related to growth and biological processes closely related to mycelial growth and metabolism were downregulated. RNA-seq also revealed that chitosan altered the expression of genes related to secondary metabolism, fungal cell wall formation and polysaccharide synthesis, and metabolism. Meanwhile, weighted gene co-expression network analysis showed that, genes expression in the module positively correlated with mycelial growth was significantly reduced in the HC treatment; and the results were verified by real-time quantitative polymerase chain reaction. Conclusions The co-inhibition effect of HAs and chitosan on A. solani is associated with downregulated genes expression correlated with mycelial growth. [ABSTRACT FROM AUTHOR]

With increasing global awareness of soil health, attention must be paid to fluorine exposure in soils, which poses a threat to human health. Therefore, this study aimed to study the fluorine adsorption characteristics of swine manure and straw biochars and their impact on fluorine adsorption-desorption in soil with batch experiments. The biochar samples originated from high-temperature anaerobic cracking of swine manure (350°C, 500°C, and 650°C) and straw (500°C). Results indicated that the adsorption of soil fluorine reached adsorption equilibrium at around 4 h after the mixing of swine manure and straw biochar. Fluorine adsorption kinetics using these biochars conformed to the quasi-two-stage kinetic model. The fluorine adsorption kinetics for biochar-treated soils conformed to the double-constant equation and the Elovich equation, and the soil treated with straw biochar showed the fastest fluorine adsorption rate. The adsorption isotherms of fluorine for biochars and biochar-treated soils could be fitted by the isothermal adsorption model of Langmuir and Freundlich. The maximal equilibrium quantity of fluorine was 73.66 mg/g for swine manure biochar. The soil, adding with 2% of swine manure biochar achieved with showed at 650°C had the smallest adsorption. This study also shows that the adsorption of fluorine by biochar gradually decreased with the increase of pH. Comparing with other factors, the mixture pH with biochars added had a significant effect on fluorine adsorption. The decreased fluorine adsorption capacities for soils treated with swine manure and straw biochars were closely related to the increased pH in soils after adding biochars. Considering the fluorine threat in soil, this study provides a theoretical basis for the application of biochars on soil fluorine adsorption. [ABSTRACT FROM AUTHOR]

Livestock manure is one of the most important pools of antibiotic resistance genes (ARGs) in the environment. Aerobic composting can effectively reduce the spread of antibiotic resistance risk in livestock manure. Understanding the effect of aerobic composting process parameters on manure-sourced ARGs is important to control their spreading risk. In this study, the effects of process parameters on ARGs during aerobic composting of pig manure were explored through data mining based on 191 valid data collected from literature. Machine learning (ML) models (XGBoost and Random Forest) were utilized to predict the rate of ARGs changes during pig manure composting. The model evaluation index of the XGBoost model (R2 = 0.651) was higher than that of the Random Forest (R2 = 0.490), indicating that XGBoost had better prediction performance. Feature importance was further calculated for the XGBoost model, and the XGBoost black box model was interpreted by Shapley additive explanations analysis. Results indicated that the influencing factors on the ARGs variation in pig manure were sequentially divided into thermophilic period, total composting period, composting real time, and thermophilic stage average temperature. The findings gave an insight into the application of ML models to predict and decipher the ARG changes during manure composting and provided suggestions for better composting manipulation and optimization of process parameters. [ABSTRACT FROM AUTHOR]

Copyright of BIOAGRO is the property of Revista BIOAGRO 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 return of straw and manure to agricultural fields can impact soil organic carbon (SOC) and biological properties. However, there is a lack of research on how to use swine manure, maize straw, and various conditioners together affects soil bacterial and fungal populations. This study aimed to investigate six treatments, namely, only maize straw (S00), maize straw combined with swine manure (S0Z), maize straw combined with biochar and swine manure (SCZ), maize straw combined with boron slag and swine manure (SBZ), maize straw combined with biological agent and swine manure (SJZ), and maize straw combined with bio-organic fertilizer and swine manure (SFZ). The results showed that after the two-year return, all treatments increased the SOC content in 2023, which was 12.55–26.89% higher than S00. And the SCZ treatment significantly increased the soil organic carbon (SOC), dissolved organic carbon (DOC), easily oxidizable carbon (EOC), particulate organic carbon (POC), and microbial biomass carbon (MBC) content by 26.89%, 25.44%, 56.88%, 16.08%, and 43.54%, compared to S00. A redundancy analysis (RDA) showed that the continuous application of manure, maize straw, and conditioners has a positive impact on the diversity and abundance of soil microbial communities, enhancing the accumulation of soil carbon. Furthermore, our research revealed that soil fungi exhibited higher sensitivity in soil carbon composition following the addition of manure, straw, and conditioners to agricultural fields than bacteria. In conclusion, the addition of different conditioners to the fields is beneficial to biodiversity conservation from the perspective of achieving soil carbon storage and soil protection. Our findings suggested that the combination of maize straw, biochar, and swine manure was been proven to be the most effective treatment for increasing labile organic carbon fractions and enhancing the microbial community. [ABSTRACT FROM AUTHOR]

Using swine manure biochar and biogas slurry in agriculture proves to be an effective strategy for soil improvement and fertilization. In this study, a pot trial on the growth of lotus root was conducted to investigate the persistent effects of applying 350°C swine manure biochar (1% and 2%) and biogas slurry (50% and 100%) on soil nitrogen nutrient and lotus root quality. The results showed that compared to chemical fertilizer alone (A0B0), swine manure biochar significantly increased soil nitrogen content after one year of application. The contents of total nitrogen (TN), alkali-hydrolyzed nitrogen (AHN), ammonium nitrogen (NH4 + −N) increased by 17.96% to 20.73%, 14.05% to 64.71%, 17.76% to 48.68% and 2.22% to 8.47%, respectively, during the rooting period. When swine manure biochar was present, the application of biogas slurry further elevated soil nitrogen content. The co-application of swine manure biochar and biogas slurry significantly increased soil nitrogen content, and the 100% nitrogen replacement with biogas slurry combined with 2% swine manure biochar (A2B2) treatment exhibited the most significant enhancement effect during whole plant growth periods. Soil enzyme activities, including soil protease (NPT), leucine aminopeptidase (LAP), b-glucosidase (β-GC) and dehydrogenase (DHA), showed a tendency to increase and then decrease with the prolongation of lotus root fertility period, reaching the maximum value during the rooting period. Compared to A0B0, the treatment with 2% swine manure biochar had the most significant effect on enzyme activities and increased the lotus root’s protein, soluble sugar, and starch contents. Nitrate content decreased with the application of 2% swine manure biochar as the amount of biogas slurry increased. In conclusion, swine manure biochar effectively improved soil nitrogen content, enzyme activity, and lotus root quality. Even after one year of application, 2% swine manure biochar had the best enhancement effect. [ABSTRACT FROM AUTHOR]3− −N) increased by 17.96% to 20.73%, 14.05% to 64.71%, 17.76% to 48.68% and 2.22% to 8.47%, respectively, during the rooting period. When swine manure biochar was present, the application of biogas slurry further elevated soil nitrogen content. The co-application of swine manure biochar and biogas slurry significantly increased soil nitrogen content, and the 100% nitrogen replacement with biogas slurry combined with 2% swine manure biochar (A2B2) treatment exhibited the most significant enhancement effect during whole plant growth periods. Soil enzyme activities, including soil protease (NPT), leucine aminopeptidase (LAP), b-glucosidase (β-GC) and dehydrogenase (DHA), showed a tendency to increase and then decrease with the prolongation of lotus root fertility period, reaching the maximum value during the rooting period. Compared to A0B0, the treatment with 2% swine manure biochar had the most significant effect on enzyme activities and increased the lotus root’s protein, soluble sugar, and starch contents. Nitrate content decreased with the application of 2% swine manure biochar as the amount of biogas slurry increased. In conclusion, swine manure biochar effectively improved soil nitrogen content, enzyme activity, and lotus root quality. Even after one year of application, 2% swine manure biochar had the best enhancement effect. [ABSTRACT FROM AUTHOR]

Biochar has attracted increasing attention as an additive for enhancing the performance of anaerobic digestion (AD), but the effect of biochar on microbial regulatory mechanisms in enhancing AD performance is unclear. To investigate how biochar modulates the process of AD, different inoculum sources including cellulose–peptone–swine inoculum (CPI) and swine manure inoculum (SMI) were designed to determine the effect of biochar on the performance and microbial communities of anaerobic digestion of the feedstock concentration from 1 to 6%. The results showed that the methane yields of CPI seeds were higher 20.3–38.7% than those of SMI seeds without a biochar addition, whereas the biochar addition reduced 5.3 and 23.1% of the corresponding methane yield of CPI and SMI, respectively. The biochar enhances the accumulation of volatile fatty acids (VFAs) and weakens the potential ammonia inhibition by adsorption, and it can improve the degradation rate of organic content of soluble COD for different inoculum sources. Microbial community analyses showed that the biochar addition could facilitate the growth of Bacteroidetes and Clostridiales, and it enriched the relative abundance of hydrogenotrophic methanogens Methanobrevibacter and Methanobacterium. Overall, although the modulation of biochar possessed different effects on the anaerobic digestion performance, it contributed to the stability and degradation efficiency of the digestion system. The recycling implication of biochar is critical to realizing a low-carbon and renewable treatment system for organic wastes. [ABSTRACT FROM AUTHOR]

The degradation of agricultural residues and their bioconversion to methane is still hampered by the search for pre-treatment strategies due to the lignocellulosic content that limits the process efficiency. Adding an enriched microbial consortium could be an alternative for the biological treatment of lignocellulosic biomass. Therefore, during the degradation process, it is necessary to study the dynamics and structure of the microbial community. The objective of this study was to evaluate the addition of an enriched microbial consortium and its effect on the methane-producing prokaryotic community during the anaerobic co-digestion of rice straw and swine manure. Two 10 L semi-continuous stirred tank reactors were used (control and bioaugmentation), during 70 days at 35 ± 2 °C, increasing organic loading rates up to 1.8 g VS/L/d. The diversity and dynamics of the microbial community were analyzed and taxonomic identification was obtained by Ion Torrent metagenomic technique. A higher production was achieved in the bioaugmented reactor (approx. 344 LN/kgVS) concerning the control reactor, increasing the methane yield by 40% (v/v). The metagenomic method allowed the identification down to the genus and species level of the microbial consortium and the prokaryotic community of the reactors, which enabled the assumption of possible metabolic pathways. In both reactors, species diversity decreased over time, indicating a greater specialization of the microbial community. Cellulolytic and methanogenic acetoclastic microorganisms were favored, which supported the higher methane production obtained. The results demonstrate that the consortium could be used as a bioproduct to treat agricultural wastes for energy purposes. [ABSTRACT FROM AUTHOR]

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office 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 utilization of biochar's as soil amendments for enhancing nutrient retention in subsoils present potential limitations. To address this issue, we conducted a greenhouse experiment to assess the effects of various biochar's derived from animal manures (swine manure, poultry litter, cattle manure) and plant residues (rice straw, soybean straw, corn straw) when applied to surface of an acidic soil. Our study focused on wheat crops under a no-tillage system, with a subsequent evaluation of the residual impacts on soybeans. The experimental design involved the application of biochar's at different rates i.e. 10 and 20 Mg ha−1, followed by the assessment of their influence on NPK levels, pH, and exchangeable Al in stratified soil layers (0–5, 5–10, 10–15, and 15–25 cm). Furthermore, we investigated the interplay between biochar doses and the application of nitrogen (N) in the top 5 cm of soil, specifically examining NO 3 - , NH 4 + , P and K levels. Our findings revealed that in the top 5 cm of soil, biochar doses and N application significantly affected NO 3 - , NH 4 + , P and K concentrations. However, in deeper soil layers, no significant differences were observed among biochar doses with or without N application. Interestingly, K levels were impacted throughout all soil depths, regardless of the presence or absence of N application. Moreover, biochar application up to a 5 cm depth induced favorable changes in soil pH and reduced exchangeable Al. In contrast, deeper layers experienced a decrease in soil pH and an increase in exchangeable Al following biochar treatment. In conclusion, our study demonstrates that biochar's can effectively retain NPK nutrients, enhance soil pH, and decrease exchangeable Al, independent of the type and dosage of application under a no-tillage system. Nonetheless, the efficacy of biochar amendments may vary with soil depth and type of nutrient, warranting careful consideration for maximizing their benefits in sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

A 16-week incubation experiment was conducted to determine the pattern of nitrogen (N), phosphorus (P), and sulphur (S) mineralization in soils treated with poultry manure slurry (PMS), poultry manure with bedding (PMB), cattle manure (CM), horse manure (HM), rabbit manure (RM), swine manure (SM), and goat and sheep manure (GSM) applied at 120 kg N ha−1. The concentrations of nitrate–N (NO3-N), ammonium-N (NH4-N), total mineral nitrogen (TMN), available P, and S were determined fortnightly. Result showed that SM and HM had significantly (p ≤ 0.05) higher C:N, C:P, C:S, N:P and N:S than other manures. The percentage of TMN, P, and S mineralized was in the order of SM > CM > HM > GSM > RM > PMB > PMS. From 8 to 14 weeks, SM, CM, HM, GSM, and RM exhibited net negative ammonification, while net positive nitrification of NO3-N occurred from 6 to 14 weeks of incubation in all manures. Soil treated with SM had a significantly higher proportion of total mineral N, available P, and S by 24, 54, and 45%, respectively. PMS had the highest mineralization and concentration of TMN, P and S; and peak at 10, 8, and 6 weeks, respectively. NO3-N was the dominant form of total mineral N (R2 = 0.99), and positive correlation occurred between TMN and cumulative P (R2 = 0.82) and S (R2 = 0.94). The study concluded that manure quality and properties are good predictors of N, P, and S mineralization. [ABSTRACT FROM AUTHOR]

Simple Summary: The blowfly, Aldrichina grahami, is widely recognized as a highly significant insect in forensic investigations. Despite the pivotal role of gut microbes in various facets of insect biology, limited knowledge exists regarding the gut microbiome of A. grahami. To investigate the gut bacterial community of A. grahami and explore its stability, diet and developmental stage were selected as the two variables. Larvae were reared on bovine liver, swine manure, and chicken manure, and high-throughput sequencing was performed on the 1st, 2nd, and 3rd instar larvae and the newly emerged adults. Our results revealed that the dominant genera Vagococcus, Providencia, Lactobacillus, and Morganella were present in more than 80% of gut samples. The alpha and beta diversity of the gut bacterial community do not vary significantly across different diets and developmental stages. Our results indicated that the bacterial community in the gut of A. grahami exhibits remarkable stability, and the dominant genera Vagococcus, Providencia, Lactobacillus, and Morganella might be potential core microbes in the gut microbial community. The blowfly, Aldrichina grahami (Diptera: Calliphoridae), is a well-known forensically important insect. Basic data related to A. grahami have been well documented; but despite the pivotal role of gut microbes in various facets of insect biology, little is known about its gut microbiome. To investigate the gut bacterial community of A. grahami and explore its stability, diet and developmental stage were selected as the two variables. Larvae were reared on bovine liver, swine manure, and chicken manure, and high-throughput sequencing of the 1st, 2nd, and 3rd instar larvae and the newly emerged adults was performed. According to our results, the alpha diversity of the gut bacterial community did not significantly vary among different diets and developmental stages. Principal coordinate analysis revealed that the gut microbiome of A. grahami clustered together among different diets and developmental stages. The main phyla in the gut microbial community of A. grahami were Firmicutes and Proteobacteria, and the dominant genera were Vagococcus, Providencia, Lactobacillus, and Morganella. These findings characterized the gut microbiome of A. grahami and demonstrated that the gut bacterial community is fairly stable. The dominant genera Vagococcus, Providencia, Lactobacillus, and Morganella have the potential to serve as core microbiomes within the gut microbial community of A. grahami. [ABSTRACT FROM AUTHOR]

North Carolina has a high density of swine farms with nearly half of the commercial operations located in two eastern counties. Lagoon and sprayfield (LS) is the dominant method of swine manure management despite pressure to transition to environmentally superior technologies. LS is an efficient and cost-effective method of waste management but has negatively impacted the environment and local communities from both discreet events (breeches, flooding) and ongoing issues (odor, disease vectors). The Multilevel Perspective Theory (MLP) is a frame for understanding the relationships between a sociotechnical regime, its surrounding landscape, and emerging niches for sustainable technology development to help align these different levels of perspective and support transitioning toward more sustainable practices. Here, a farm level is added to represent the user perspective of regime technology in complex agriculture systems (MLP + F). We demonstrate how change may influence the North Carolina swine waste management (NC SWM) system through alternative scenarios applied to a conceptual model developed with the MLP + F frame in a methodology for analyzing complex agricultural systems with input from a diverse panel of experts. This case study demonstrates how the methodology can be applied through two NC SWM model scenarios analyzed with fuzzy cognitive mapping techniques. The first scenario explores whether panel recommended changes generate a shift toward sustainable manure management. Inference results suggest that experts have a broad understanding of how these goals may be achieved, but strategies are needed to enhance the specificity of proposed changes. Testing scenarios with more targeted interventions within specific subsystems could provide greater guidance with regard to policy, economic factors, farm practices, or societal demands. The second scenario considers the systemic effect of introducing a manure dewatering process on swine operations, with and without landscape support. Results from this scenario indicate that the more landscape support is engaged, the greater the impact on desirable outcomes. However, contradictions emerged between different versions of this scenario such as increased negative public perceptions despite positive community outcomes. This may require further investigation to tease out potential misalignment between perceptions of a complex system and actual system behaviors. [ABSTRACT FROM AUTHOR]

Manure application is a recommended method to improve soil quality and mitigate global warming via soil carbon (C) sequestration. However, such application can significantly increase ammonia (NH3) volatilization loss and cause secondary environmental problems, such as acidification, eutrophication, and particulate matter formation. To investigate the potential of reducing NH3 emissions in flooded rice paddies, three types of stabilized swine manure amendments (fresh, composted, and biochar) were applied at a rate of 12 Mg ha−1 (dry weight) under standard fertilization (N–P2O5–K2O = 90–45–57 kg ha−1), and NH3 emission was characterized using the static chamber method. Regardless of manure management practices, NH3 fluxes increased significantly immediately after application of an inorganic nitrogen (N) fertilizer (urea). The manure was applied completely as the basal fertilizer before rice transplanting, but the NH3 emission rates increased more dramatically following urea application in the manure treatments. Fresh and composted manure applications significantly increased seasonal NH3 volatilization losses compared to the control but the biochar did not. Compost manure significantly increased rice grain productivity owing to the higher N content, while fresh and biochar manures did not increase rice productivity because of fewer panicles per hill and fewer grains per panicle. Consequently, biochar application resulted in lower NH3 flux intensity and seasonal NH3 flux per grain yield, whereas fresh and compost manures substantially increased this intensity. Therefore, biochar manure may be a more reasonable organic amendment than fresh and composted manures for reducing NH3 emission impacts on rice paddies.

Aerobic composting (AC), anaerobic digestion (AD), and anaerobic manure storage tank (AMST) are conventional systems for treating liquid swine manure (LSM). In this study, life cycle assessment (LCA) was used to evaluate environmental impact in both construction and operation phases to compare AC, AD, and AMST systems. The results were obtained using SimaPro® with ReCiPe impact assessment method. The system boundary was from cradle to grave, and the adopted functional unit was 10.0 m3 of LSM. LCA results showed that steel and cement were the inputs with higher environmental impact in construction phase in AC and AD with average percentages of 74.25 and 24.56%, and 57.17 and 17.30%, respectively. For AMST, high-density polyethylene (HDPE) was more significant with average impact of 83.37%. The comparison between the construction and operation phases of each system individually showed that the construction causes the higher impact in AC and AD, while in AMST was the operation phase. The comparison between the construction phases of the systems showed that AC resulted in higher environmental impacts than in AD and AMST in all impact categories. In relation to operation phase, AMST system causes higher impact compared to AD and AC. Finally, the global comparison of systems showed that the AD with energy use has the better environmental performance. The high use of steel and cement in construction phase and methane production in operation phase have a significant impact on the global life cycle. [ABSTRACT FROM AUTHOR]

The global crisis associated with COVID-19 and the Russia-Ukraine conflict has affected progress towards the Sustainable Development Goals (SDGs). Projections for SDG7 (Ensure access to affordable, reliable, sustainable, and modern energy for all) indicate a slowdown in the pace of electrification. Thus, the problem of poverty will persist in many regions as long as access to electricity remains difficult. This work analyzes some solutions to the lack of electricity supply in a rural community using organic waste from its economic activity and the integration of other available renewable sources to make electricity affordable and reliable. A model that minimizes the levelized cost of energy and restricts the proportion of annual energy not supplied to less than 5% of the community's annual demand optimizes the performance of off-grid and on-grid systems. These systems have in common the production of electricity from biogas produced from swine manure, supplemented with wind and solar generation. Batteries and diesel generators support the operation of off-grid systems. As expected, the grid-connected system presented the best performance; however, the result reaffirms the need for governments to ensure the policy and infrastructure conditions that facilitate the grid connection of vulnerable communities to achieve SDG7. [ABSTRACT FROM AUTHOR]

This study demonstrated the feasibility of enhanced biological phosphorus removal coupled with in-situ fermentation (EBPR-F) to improve phosphorus removal from real digested swine wastewater. We used fermentable substrates (casein hydrolysate and glucose) as the external carbon sources to promote in-situ fermentation and enhance biological phosphorus removal. Compared with conventional EBPR dominated by Candidatus Accumulibacter, EBPR-F had significantly better phosphorus removal with enriched polyphosphate-accumulating organisms (PAOs). Under supplementation with 100 mg/L glucose, total phosphorus (TP) removal was over 95% in EBPR-F, with an average TP concentration in the effluent below 1.0 mg/L, satisfying the discharge standard (8 mg P/L) in China. The PAO activity and relative abundance of Candidatus Accumulibacter (44.7% ± 3.1%) and Tetrasphaera (18.1% ± 6.6%) in EBPR-F were much higher than those in EBPR. The improvement in phosphorus removal of EBPR-F was due to the enrichment of Tetrasphaera through the enhanced in-situ fermentation, as Tetrasphaera can efficiently ferment complex organic matter and provide bioavailable organics for phosphorus removal. [ABSTRACT FROM AUTHOR]

Simple Summary: The rise of malodor complaints from residents around swine farms and greenhouse gas (GHG) emissions from manure have become a global concern. Although various technologies have been developed to reduce gas emissions from swine farms, only a few have been successfully applied. In Korea, a bio-liquor circulation system (BCS) that controls odor by diluting slurry pit manure with biologically treated manure (bio-liquor) has been proposed as an odor control technology. However, the successful implementation of BCS has been hindered due to the lack of suitable bioreactor control strategies. Therefore, to effectively use BCS, it is crucial to develop an optimized control technology for bioreactors and system operations. Hence, this study aimed to evaluate the effectiveness of a novel real-time BCS controlled by tracking the time profiles of the oxidation reduction potential (ORP) and pH (mV) within two bioreactors in an experimental swine farm set up to improve manure treatment efficiency and reduce malodor at farm scale. The study's results showed that the real-time BCS successfully controlled and optimized the bioreactor and the entire process, effectively reducing the concentrations of nitrogen and organic matter in the swine manure in the slurry pit, and subsequently the malodor. Recently, circulating biologically treated manure in slurry pits has been used as an odor reduction technology, but few successful results have been reported, due to the lack of proper control strategies for bioreactors. This study was conducted to investigate the performance of the developed real-time controlled bio-liquor circulation system (BCS) at farm scale. The BCS was operated sequentially as per swine manure inflow (anoxic, aerobic, and settling) circulation to the slurry pit. Each operational phase was self-adjusted in real-time using a novel algorithm for detecting the control point on the oxidation reduction potential (ORP) and pH (mV)–time profiles, the nitrogen break point (NBP), and the nitrate knee point (NKP) in the aerobic and anoxic phases, respectively. The NH4-N in the slurry manure was thoroughly removed (100%) in the bioreactor, optimizing the duration of each operational phase by accurately detecting real-time control points. The newly developed real-time BCS decreased the nitrogen and organic matter in the slurry pit by >70%, and the potential ammonia and methane emissions by 75% and 95%, respectively. This study highlights that improved BCS that utilizes ORP tracking and pH (mV)–time profiles can effectively optimize BCS operation, and thereby reduce malodor and GHG emissions from swine farms. [ABSTRACT FROM AUTHOR]

Strobilanthes cusia is a herb species of the Acanthaceae family. This plant is a well-known dye crop. A participatory experiment was conducted regarding S. cusia cultivation under bamboo stands. Strobilanthes cusia seedlings were planted in split plot design consisting of two treatments, with bamboo canopy cover (dense canopy, moderate canopy, sparse canopy, open area) as the main plots and the use of fertiliser (control, swine manure, NPK 16-16-16, NPK plus swine manure) as the sub plots, with each plot being 10 m2. Strobilanthes cusia seedling performance was best under sparse canopy, where on average shoot length was 22.80 cm, the number of leaves was 45.3, and leaf yield at the edge and middle of plot were 1.90 kg/plot and 1.86 kg/plot, respectively. Wet paste yield was best from S. cusia cultivated under the sparse canopy with NPK plus manure (337 g m−2) resulting in dried paste at 0.71 g m−2. Financial feasibility showed that intercropping S. cusia under a natural bamboo stand of Dendrocalamus asper delivered net present value of Indonesian Rupiah 28,951,568 (USD 1,587) with benefit cost ratio of 1.58. [ABSTRACT FROM AUTHOR]

The work focuses on the study of hydrochar upgrading from hydrothermal carbonization (HTC) of swine manure by HCl-assisted HTC or washing with HCl or acetone, as a post-treatment to conventional HTC. Conventional HTC of swine manure yields a low-quality hydrochar (C content ~ 38 wt.%, higher heating value (HHV) ~ 15 MJ kg−1, and ash content up to 32 wt.%). HCl-assisted HTC (0.5 M HCl at 230 ℃) substantially reduced the ash content up to ~10 wt.% in the hydrochar and increased the C content to 58 wt.%, reaching a HHV of 23 MJ kg−1. However, the N and S contents remained at values similar to those of the swine manure. Washing post-treatment of conventional hydrochars with HCl or acetone significantly improved the C content and the HHV in the range 47–58 wt.% and 19–25 MJ kg−1, respectively, as well as the ash removal with values 7-11 wt.%. Washing the hydrochar with acetone significantly reduced the N and S contents, obtaining a carbonaceous material with properties suitable for solid biofuel according to ISO/TS 17225–8, (N < 3 wt.%; S < 0.15 wt.%; HHV > 17 MJ kg−1; and ash < 10 wt.%). Hydrochars obtained by HCl-assisted HTC and HCl/acetone washing post-treatment yielded higher thermal stability, as well as better reactivity and low ash agglomeration indexes than compared to conventional hydrochars. Washing post-treatment with acetone proved to be the best strategy to obtain improved hydrochars from swine manure for industrial use as a solid biofuel. [ABSTRACT FROM AUTHOR]

Recently, there has been a significant focus on the issue of pollution caused by livestock and poultry rearing, which is recognized as a prominent contributor to nonpoint source pollution in the agricultural sector. This study employed the life cycle assessment (LCA) methodology to evaluate the environmental impact of several pig manure processing scenarios with the aim of determining the appropriate solid–liquid separation tool for large-scale pig farms. The findings indicate that the utilization of a screw extruder for solid–liquid separation in Scenario 2 has a lower environmental impact. In contrast to Scenario 1, Scenario 2 exhibits reduced environmental potential in the areas of global warming, human toxicity, acidification, and eutrophication. Specifically, the global warming, human toxicity, acidification, and eutrophication impacts decreased by 56%, 81%, 83%, and 273%, respectively, due to the implementation of solid–liquid separation. The type of solid–liquid separation equipment used during the processing of swine manure, as well as the subsequent treatment, have a significant impact on environmental emissions. Compared to Scenario 2, Scenario 3, which utilizes a centrifugal microfilter for solid–liquid separation, exhibits a lower environmental impact in terms of human toxicity, resulting in a reduction of 0.736 kg DCB-eq. In general, solid–liquid separation is a viable and environmentally friendly method for the disposal of waste from large-scale pig farms. The adoption of this method is highly recommended. During its implementation, careful consideration should be given to factors such as separation efficiency and pollution emissions. It is crucial to select appropriate equipment for solid–liquid separation to effectively process the waste. [ABSTRACT FROM AUTHOR]

The open-air storage and disposal of livestock waste from family-operated livestock farms can be a potential health threat to rural residents. In this study, the occurrence and seasonal distribution of 8 potentially toxic elements, 24 antibiotics, and 4 estrogens were investigated in 44 waste samples from 11 rural farms in North China. The results showed that these micropollutants were ubiquitous in livestock waste, with concentration ranges of 238.9–4555 mg/kg for potentially toxic elements, not detected (ND) to 286,672 μg/kg for antibiotics and ND to 229.5 μg/kg for estrogens. The pollutants in animal wastes showed seasonal variation. Since these wastes are directly applicable to nearby farmland without treatment, the risks those wastes pose to farmland soils were also evaluated. Risk assessment results showed that Zn, Cd, Hg, FF and DC in swine manures were at high risk, while total estrogens in chicken and dairy cattle manures were at high risk. The results will provide important data for the regulation of animal wastes produced by small-scale livestock farms in rural areas of China. [ABSTRACT FROM AUTHOR]

For how long the nutrient supply from long‐term application of manure and swine effluent will last to sustain crop production after applications had ceased is a research gap. We quantified the change in soil chemical properties 12 years after cattle manure and swine effluent applications had ceased. Data were collected in 2008 (termination of applications) and 2020 on a long‐term animal waste study at the Kansas State University, Southwest Research‐Extension Center near Tribune, KS. Treatments were three levels of cattle manure and swine effluent (phosphorus, P; nitrogen, N; and 2N) and an untreated control. Soil profile NO3‐N declined 78%–95%, 70%–82%, and 58% from the initial amount in 2008 compared to the amount remaining in 2020 in the swine effluent, cattle manure, and an untreated check, respectively. Profile NO3‐N levels were greatly elevated by the P‐based swine effluent treatment and the 2N rate of both cattle manure and swine effluent and remained high (>250 kg ha−1) after 12 years. Total nitrogen in the surface soil decreased by 11%–27% for cattle manure treatments with little change in the swine effluent and check treatments. Total carbon concentration in the surface soil decreased from 22% to 31% for cattle manure treatments and from 7% to 14% for swine effluent and check treatments. Mehlich‐3 P decreased significantly for the cattle manure treatments (41%–53%) but still remained very high (>100 mg kg−1). Soil test P levels in the swine treatments were similar to the check treatment. Application of cattle manure and swine effluent has lasting effects on many soil chemical properties long after ceasing applications. Core Ideas: Twelve years after treatment withdrawal, NO3‐N in profile decreased by 70%–82%, 78%–95%, and 58% from cattle manure, swine effluent, and check treatments, respectively.Total carbon concentration decreased 22%–31% for cattle manure and 7%–14% for swine effluent and check treatments.Mehlich‐3 P decreased by 41%–53% for cattle manure, 36%–58% for swine effluent, and 35% for the check.Cattle manure treatments continued to have high levels of soil test P 12 years after the last application.Application of swine effluent based on P requirement resulted in a buildup of NO3‐N which persisted for 12 years. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental 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.)

This study was conducted to examine the operation statuses of on-site swine wastewater treatment facilities through surveys and field surveys on pig farms and to propose effective operation models. Field analyses and surveys of pig farms indicate that technical and financial support systems are required for both farms and on-site swine wastewater treatment facilities. Public environmental services have been proposed as an effective support system, in which private sewage treatment facilities are entrusted to professional environmental management agencies, and the costs are shared by local governments and facility owners. However, securing a stable budget represents a challenge to implementing public environmental services. Thus, this study proposes a collaborative manure management model composed of individual farms, professional environmental management agencies, and local governments to address the shortcomings of public environmental services. To effectively manage pig manure, the flexible application of discharge standards, diversification of pollutant reduction management techniques (e.g., feed management), and periodic review of permits must be considered. Additionally, the reinforcement of discharge standards for individual purification facilities, control of the livestock density and number, and impacts of livestock manure discharge on riverine ecosystems must be considered.

ABSTRACT Excessive phosphorus (P) applications can increase nutrient levels in the soil, facilitating its transference to aquatic environments and causing contamination. Thus, the environmental P threshold (P-threshold) is a tool to establish a sound level of P in the soil, in which P values below the threshold are harmless to the environment. This study aimed to establish a P-threshold equation for the soils of Mato Grosso State, Brazil. Twenty samples of representative soils from the main swine production regions of the State were collected. These samples were characterized chemically and in terms of P adsorption capacity, then incubated with P rates for 30 days. After incubation, the water-soluble P content (P-water) and the available P content were determined by Mehlich-1 method (P-Mehlich-1). The relationship between P-water and P-Mehlich-1 allowed the determination of the P-Mehlich-1 content from which the amount of nutrient in water increases abruptly, establishing this point as the limit P (P-limit). Subsequently, the P-limit values were plotted against the clay content of the soils, and the resulting equation was used to calculate the P-threshold by adding a safety margin of 20 % to the P-limit versus clay equation. The model was tested on 120 soil samples from Mato Grosso State, and it was able to separate them into two groups with low and high P-water, classified as below or above P-threshold, respectively. Based on that, the simplified equation “P-threshold (mg dm-3) = 13 + 0.5 * % clay” was proposed.

Asphalt is an essential material in the construction of asphalt pavements. Due to its high demand and dependence on petroleum, it is crucial to use greener materials that can fully or partially replace petroleum-based binders. The characteristics of asphalt cause the bio-binder obtained through a hydrothermal liquefaction process from swine manure to have great potential to be used as a modifier due to its similarities with asphalt, contributing to the construction of more sustainable roads. Thus, this paper characterizes an asphalt binder modified with a new bio-binder obtained from swine manure at different rates (0%, 10%, and 20%). Several characterization tests were performed, including penetration, ring and ball, Fraass, viscosity, Cleveland open cup, and the UCL method. Furthermore, the possible leaching of the bio-binder was studied, showing no environmental problems. Results from the rheological tests showed that as the content of bio-binder increases, the softening temperature, Fraass breaking point, and viscosity of the bio-modified asphalt binder decrease, indicating the lower consistency of the bio-modified binder and its greater thermal susceptibility. [ABSTRACT FROM AUTHOR]

Novel applications of the closed-vessel conductively heated digestion system (CHDS) are proposed to digest biomass, biochar, oyster shell flour, bone meal and swine manure for the determination of Ca, K, Mg, Na, Cu, Fe, Mn, and Zn by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS). The performance of the digestion method using 14 and 7 mol L−1 HNO3 was checked by analyzing soil, rock, and plant certified reference materials (CRMs). For comparative purposes, all samples were analyzed after microwave-assisted digestion (MW-AD). Results obtained for most analytes by the closed-vessel conductively heated digestion system (CHDS) were in agreement with certified values and those attained by the comparative digestion method. The use of 7 mol L−1 HNO3 furnished lower blanks for most analytes and was effective to prepare challenging samples as biomass, biochar, shell and bone meal, swine manure, plants, soil, phosphate rock, and may be a good alternative for elemental determinations using most analytical techniques that rely on solution-based sample introduction systems. The detection limits (dry basis, mg kg−1) for Ca, Cu, Fe, K, Mg, Mn, Na, and Zn were 3, 0.4, 4, 4, 0.7, 0.4, 3, and 2, respectively. The mean relative standard deviations were close to 4.9% for closed-vessel conductively heated digestion (CHDS) and 5.9% for microwave-assisted digestion (MW-AD). [ABSTRACT FROM AUTHOR]

Tetracycline is frequently found in various environments and poses significant ecological risks. Calcium hydroxide-modified biochar has shown potential as a material for removing multiple classes of pollutants from wastewater streams. The tetracycline-adsorption performance and mechanism of alkali-modified biochars derived from nine wastes (corn straw, rice straw, swine manure, cypress powder, wheat straw, peanut shell, walnut shell powder, soybean straw, and corncobs) were investigated in the study. Among the four alkalis tested, calcium hydroxide exhibited the most effective modification effects at a pyrolysis temperature of 500 °C. Straw biomass was most suitable to be modified by calcium hydroxide, and calcium hydroxide-modified biochar showed the highest adsorption performance for tetracycline. The maximum adsorption capacities were 8.22 mg g−1 for pristine corn straw biochar and 93.46 mg g−1 for calcium hydroxide-modified corn straw biochar. The tetracycline adsorption mechanism by calcium hydroxide-modified corn straw biochar involved hydrogen bonding, oxygen-containing functional groups, Ca2+ metal complexation, and electrostatic attraction. Consequently, calcium hydroxide-modified corn straw biochar emerges as an environment-friendly, cost-effective, and efficient tetracycline adsorbent. [ABSTRACT FROM AUTHOR]

The Quick Wash (QW) treatment extracts phosphorus (P) from manure and municipal sludge (MS), producing an organic acidified by-product with adequate nitrogen (N):P ratio to meet crop N requirements. Yet, data on crop response to N using QW by-products are lacking. We evaluated the response of annual ryegrass (Lolium multiflorum Lam.) and potential N leaching in sandy soil to N applications using raw wastes, their corresponding QW by-products, and ammonium sulfate (AMS) fertilizer. Treatments included a control (no amendment added), raw and acid-washed chicken litter, dairy and swine manure, MS, and AMS at 100, 200, and 400 kg N ha−1. We found no significant differences in annual ryegrass yield and N uptake between the raw and acidified organic QW by-products. However, ryegrass produced 4–30% more biomass with AMS than organic amendments. The total residual soil inorganic N under AMS treatments ranged between 6.3 and 67.9 mg pot−1 and accounted for 5–17% of the total N applied, but it was <1% for all the organic amendments. We found no differences in soil N leaching between raw and acid-washed forms of each organic soil amendment. Our results indicated that acidified organic QW by-products can improve environmental quality by substantially reducing the amount of applied P with no penalties for crop yield losses compared to raw manure and MS. [ABSTRACT FROM AUTHOR]

While the prudent and reasonable use of veterinary antimicrobial agents in food-producing animals is necessary, researchers over the decades have shown that these antimicrobial agents can spread into the environment through livestock manure and wastewater. The analysis of the occurrence of antimicrobial compounds in soil samples is of a great importance to determine potential impacts on human and animal health and the environment. In this study, an affordable, rugged and simple analytical method has been developed for the determination of twenty-nine antimicrobial compounds from five different classes (tetracyclines, fluoro(quinolones), macrolides, sulfonamides and diaminopirimidines). Liquid–liquid extraction (LLE) with extract filtration combined with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was the best strategy for the simultaneous determination of all analytes. The developed method was validated according to the Commission Implementing Regulation (EU) 2021/808. The limit of detections (LODs) ranged from 0.5 to 2.0 µg/kg, while the limit of quantitation (LOQ) was established at 1.0 to 20.0 µg/kg. The developed method was successfully applied for the determination of antimicrobial residues in one hundred and eighteen soil samples obtained from four European countries (Austria, Czech Republic, Estonia and Portugal). Doxycycline in the concentration levels of 9.07 µg/kg–20.6 µg/kg was detected in eight of the analysed samples. Samples were collected from areas where natural fertilizers (swine or cow manure) were applied. Our method can be efficiently used to monitor anti-microbial compounds in soil samples. [ABSTRACT FROM AUTHOR]

This study characterized the solution chemistry of seven swine manure storages in Saskatchewan, Canada. Manure storages are considered a point source for potential contaminant transport studies and modeling. A variety of earthen manure storages at hog production facilities in Saskatchewan were sampled, including two earthen manure storages servicing farrow to finish operations, two servicing farrows to wean operations, and three servicing finishing operations. In terms of manure seepage, the species of most common concern is nitrogen. Ammonium nitrogen is one of the most abundant ions studied in the earthen manure storage effluent. Potassium and sodium may be cations of concern as they will likely compete with ammonium for soil exchange sites, which will affect ammonium's attenuation. Bicarbonate and chloride are the most abundant anions (bicarbonate >> chloride). High bicarbonate concentrations will likely affect the precipitation of carbonaceous minerals and may affect solution pH within seepage plumes. Earthen manure storages contain a solution composed of, as a percentage of total molal concentration, 36% ammonium, 36% bicarbonate, 8% potassium, 6% chloride, 5% sodium plus sulfate, calcium, magnesium, and other nutrients. The solution also contains approximately 6,000 mg/L organic carbon and 9,000 mg/L inorganic carbon and has a near neutral pH. As a result, the solution has low redox (Eh), resulting in nitrogen remaining in the ammonium-N form. [ABSTRACT FROM AUTHOR]