scholarly journals Microbial assemblages and methanogenesis pathways impact methane production and foaming in manure deep-pit storages

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0254730
Author(s):  
Fan Yang ◽  
Daniel S. Andersen ◽  
Steven Trabue ◽  
Angela D. Kent ◽  
Laura M. Pepple ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Methane Production ◽  
Swine Manure ◽  
Strongly Correlated ◽  
Strong Correlations ◽  
Community Assemblage ◽  
Hydrogenotrophic Methanogenesis ◽  
Deep Pit ◽  
Methane Production Rate ◽  
Deep Pits

Foam accumulation in swine manure deep-pits has been linked to explosions and flash fires that pose devastating threats to humans and livestock. It is clear that methane accumulation within these pits is the fuel for the fire; it is not understood what microbial drivers cause the accumulation and stabilization of methane. Here, we conducted a 13-month field study to survey the physical, chemical, and biological changes of pit-manure across 46 farms in Iowa. Our results showed that an increased methane production rate was associated with less digestible feed ingredients, suggesting that diet influences the storage pit’s microbiome. Targeted sequencing of the bacterial 16S rRNA and archaeal mcrA genes was used to identify microbial communities’ role and influence. We found that microbial communities in foaming and non-foaming manure were significantly different, and that the bacterial communities of foaming manure were more stable than those of non-foaming manure. Foaming manure methanogen communities were enriched with uncharacterized methanogens whose presence strongly correlated with high methane production rates. We also observed strong correlations between feed ration, manure characteristics, and the relative abundance of specific taxa, suggesting that manure foaming is linked to microbial community assemblage driven by efficient free long-chain fatty acid degradation by hydrogenotrophic methanogenesis.

scholarly journals Narasin as a Manure Additive to Reduce Methane Production from Swine Manure

2018 ◽  
Vol 61 (3) ◽  
pp. 943-953
Author(s):  
Daniel S. Andersen ◽  
Fan Yang ◽  
Steven L. Trabue ◽  
Brian J. Kerr ◽  
Adina Howe
Keyword(s):  
Methane Production ◽  
Biogas Production ◽  
Safety Concern ◽  
Swine Manure ◽  
Inhibitory Effect ◽  
Gas Production ◽  
Dose Rates ◽  
Deep Pit ◽  
Sugar Addition ◽  
Swine Operations

Abstract. High levels of methane production from swine operations have been associated with foam accumulation in deep-pit manure storage systems. This foam poses both a safety concern (i.e., flash fires) and operational challenges in managing stored manure. Mitigating methane production is one approach to controlling foam accumulation. In this study, swine manures obtained from three deep-pit storage barns in central Iowa were dosed with narasin to evaluate its inhibitory effects on methane and biogas production. Dose rates ranged from 0 to 3.0 mg narasin kg-1 manure. Overall, methane rates were reduced by 9% for each mg of narasin added per kg of manure, and this reduction was effective for up to 25 days. However, the inhibitory effect weakened with time such that no statistical difference in cumulative methane production between samples dosed with narasin and undosed controls could be detected after 120 days of incubation. In addition to methane rates, narasin addition reduced the degradation of total and volatile solids in the manure by 1.9% and 2.6%, respectively, for each mg of narasin added per kg of manure. Additional study treatments included sugar (10 g kg-1 manure) with and without narasin (1.5 mg narasin kg-1 manure). Results from this treatment showed that methane production was initially increased by the sugar addition, but the effect lasted less than six days, at which point cumulative methane production was similar to the control. When treated with both narasin and sugar, the inhibitory effect did not impact gas production during the sugar digestion phase but did reduce methane and biogas production thereafter. The addition of sugar and the rate of narasin addition caused changes to the microbial community as compared to the control. Overall, the results indicated that narasin can be an effective additive for reducing methane emission from swine manure, but further study is needed to recommend dosing frequency and to evaluate how continuous addition of manure impacts narasin effectiveness. Keywords: Biogas, Manure management, Manure treatment, Methane, Narasin, Swine manure, Swine production.

Can rumen methane production be predicted from volatile fatty acid concentrations?

2010 ◽  
Vol 50 (6) ◽  
pp. 630 ◽  
Author(s):  
D. L. Robinson ◽  
J. Goopy ◽  
R. S. Hegarty
Keyword(s):  
Fatty Acid ◽  
Feed Intake ◽  
Methane Production ◽  
Volatile Fatty Acid ◽  
Open Circuit ◽  
Strongly Correlated ◽  
Feeding Level ◽  
Poor Predictor ◽  
Feeding Cycle ◽  
Methane Production Rate

Rumen cannulated sheep (n = 12) were tested at each of three feeding levels: 0.8, 1.24 and 1.6 times maintenance. The ration (lucerne chaff) was provided in eight equal portions to emulate morning and afternoon grazing. After at least 10 days adaptation to each feeding level, methane production was measured in an open circuit calorimeter for 22 h using the same feeding regime. During measurement, 10 rumen samples were taken for volatile fatty acid (VFA) analysis by an indwelling rumen probe with a sampling tube that passed outside the calorimeter. Feed intake was strongly correlated with daily methane production (DMP, r = 0.87). Both methane production and VFA concentrations showed bimodal patterns related to the feeding cycle, but feed intake had a much smaller effect on VFA concentrations than on methane production rate. Average VFA concentration was a poor predictor of DMP. The best predictor, propionate concentration, explained 26% of the variance in DMP. The weakness of the association between VFA concentrations and methane production could be a consequence of differences in rumen volume and differences in VFA absorption associated with feeding level, although the possibility of accumulation of alternate fermentation end products or re-fermentation of VFA cannot be excluded. It is concluded that none of the suite of VFA parameters assessed offers a useful tool to predict daily methane production in grazing sheep.

scholarly journals Evaluation of acidogenesis products’ effect on biogas production performed with metagenomics and isotopic approaches

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Anna Detman ◽  
Michał Bucha ◽  
Laura Treu ◽  
Aleksandra Chojnacka ◽  
Łukasz Pleśniak ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Methane Production ◽  
Bacterial Species ◽  
Stable Carbon Isotope ◽  
Anaerobic Sludge ◽  
Methane Formation ◽  
Microbial Composition ◽  
Fermentation Products ◽  
Core Microbiome ◽  
Specific Species

Abstract Background During the acetogenic step of anaerobic digestion, the products of acidogenesis are oxidized to substrates for methanogenesis: hydrogen, carbon dioxide and acetate. Acetogenesis and methanogenesis are highly interconnected processes due to the syntrophic associations between acetogenic bacteria and hydrogenotrophic methanogens, allowing the whole process to become thermodynamically favorable. The aim of this study is to determine the influence of the dominant acidic products on the metabolic pathways of methane formation and to find a core microbiome and substrate-specific species in a mixed biogas-producing system. Results Four methane-producing microbial communities were fed with artificial media having one dominant component, respectively, lactate, butyrate, propionate and acetate, for 896 days in 3.5-L Up-flow Anaerobic Sludge Blanket (UASB) bioreactors. All the microbial communities showed moderately different methane production and utilization of the substrates. Analyses of stable carbon isotope composition of the fermentation gas and the substrates showed differences in average values of δ13C(CH4) and δ13C(CO2) revealing that acetate and lactate strongly favored the acetotrophic pathway, while butyrate and propionate favored the hydrogenotrophic pathway of methane formation. Genome-centric metagenomic analysis recovered 234 Metagenome Assembled Genomes (MAGs), including 31 archaeal and 203 bacterial species, mostly unknown and uncultivable. MAGs accounted for 54%–67% of the entire microbial community (depending on the bioreactor) and evidenced that the microbiome is extremely complex in terms of the number of species. The core microbiome was composed of Methanothrix soehngenii (the most abundant), Methanoculleus sp., unknown Bacteroidales and Spirochaetaceae. Relative abundance analysis of all the samples revealed microbes having substrate preferences. Substrate-specific species were mostly unknown and not predominant in the microbial communities. Conclusions In this experimental system, the dominant fermentation products subjected to methanogenesis moderately modified the final effect of bioreactor performance. At the molecular level, a different contribution of acetotrophic and hydrogenotrophic pathways for methane production, a very high level of new species recovered, and a moderate variability in microbial composition depending on substrate availability were evidenced. Propionate was not a factor ceasing methane production. All these findings are relevant because lactate, acetate, propionate and butyrate are the universal products of acidogenesis, regardless of feedstock.

scholarly journals Development of the Psychological Insight Questionnaire among a sample of people who have consumed psilocybin or LSD

2021 ◽  
pp. 026988112096787
Author(s):  
Alan K Davis ◽  
Frederick S Barrett ◽  
Sara So ◽  
Natalie Gukasyan ◽  
Thomas C Swift ◽  
...  
Keyword(s):  
Life Satisfaction ◽  
Longitudinal Research ◽  
Psychological Flexibility ◽  
Well Being ◽  
Survey Study ◽  
Strongly Correlated ◽  
Strong Correlations ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Therapeutic Outcomes

Background: Several measures have been developed to examine acute psychedelic effects (e.g. mystical-type and challenging experiences), but no measure assesses acute psychologically insightful experiences that may occur during psychedelic experiences. Aim: The purpose of this study was to develop and examine the psychometric properties of the Psychological Insight Questionnaire. Method: A cross-sectional survey study among psilocybin and LSD users. Respondents ( n=1661; Mage=22.9, standard deviation=8.5; Caucasian/White=83%; non-Hispanic=91%; men=72%; United States resident=66%) completed an Internet-based survey. Results: The Psychological Insight Questionnaire consists of 23 items with two subscales: (a) Avoidance and Maladaptive Patterns Insights and (b) Goals and Adaptive Patterns Insights. Construct validity of the Psychological Insight Questionnaire was supported by strong correlations of the Psychological Insight Questionnaire (and Avoidance and Maladaptive Patterns Insights and Goals and Adaptive Patterns Insights subscales) scores with the insight subscale of the Session Impacts Scale, and weak-to-moderate correlations with the Mystical Experiences and Challenging Experiences Questionnaires. Furthermore, Psychological Insight Questionnaire (and Avoidance and Maladaptive Patterns Insights and Goals and Adaptive Patterns Insights subscales) scores were moderately-to-strongly correlated with retrospectively reported increases in psychological flexibility, and well-being/life satisfaction that were attributed to a memorable psychedelic experience. Lastly, incremental validity was established showing that the Psychological Insight Questionnaire (and Avoidance and Maladaptive Patterns Insights subscale) scores predict unique variance in changes in psychological flexibility, and Psychological Insight Questionnaire (and Avoidance and Maladaptive Patterns Insights and Goals and Adaptive Patterns Insights subscales) scores predict changes in well-being and life satisfaction, beyond measures of acute mystical-type and challenging effects. Conclusions: The Psychological Insight Questionnaire has the potential to extend the understanding of the acute and enduring effects of psychedelics. Further longitudinal research is necessary to determine the long-term predictive validity of the Psychological Insight Questionnaire and to examine the role of psychological insight in predicting therapeutic outcomes.

scholarly journals Lab-assay for estimating methane emissions from deep-pit swine manure storages

2015 ◽  
Vol 159 ◽  
pp. 18-26 ◽  
Author(s):  
D.S. Andersen ◽  
M.B. Van Weelden ◽  
S.L. Trabue ◽  
L.M. Pepple
Keyword(s):  
Swine Manure ◽  
Methane Emissions ◽  
Deep Pit

Effects of thermochemical pretreatment on the anaerobic digestion of waste activated sludge

1997 ◽  
Vol 35 (8) ◽  
pp. 209-215 ◽  
Author(s):  
Shuzo Tanaka ◽  
Toshio Kobayashi ◽  
Ken-ichi Kamiyama ◽  
Ma. Lolita N. Signey Bildan
Keyword(s):  
Anaerobic Digestion ◽  
Activated Sludge ◽  
Production Rate ◽  
Methane Production ◽  
Waste Activated Sludge ◽  
Batch Experiments ◽  
Industrial Wastewaters ◽  
Thermochemical Pretreatment ◽  
Chemical Heating ◽  
Methane Production Rate

Effects of pretreatment on the anaerobic digestion of waste activated sludge (WAS) were investigated in terms of VSS solubilization and methane production by batch experiments. The methods of pretreatment studied are NaOH addition (chemical), heating (thermal) and heating with NaOH addition (thermochemical) to the domestic WAS and to the combined WAS from domestic, commercial and industrial wastewaters. The thermochemical pretreatment gave the best result among three methods in the combined WAS, i.e., the VSS was solubilized by 40-50% and the methane production increased by more than 200% over the control when the WAS was heated at 130°C for 5 minutes with the dose 0.3 g NaOH/g VSS. In the domestic WAS, the VSS solubilization rate was 70-80% but the increase of the methane production was about 30% after thermochemically pretreated. The domestic WAS consists of 41% protein, 25% lipid and 14% carbohydrate on COD basis, and the solubilization rate of protein, which is the largest constituent of the WAS, was 63% in the thermochemical pretreatment. Although the effect of the thermochemical pretreatment on the methane production was higher to the combined WAS than to the domestic WAS, the methane production rate was 21.9 ml CH4/g VSSWAS·day in the domestic WAS and 12.8 ml CH4/g VSSWAS·day in the combined WAS.

Survey on foaming deep-pit swine manure

2013 ◽  
Author(s):  
Neslihan Akdeniz ◽  
Larry D Jacobson ◽  
Charles J Clanton ◽  
Brian P Hetchler
Keyword(s):  
Swine Manure ◽  
Deep Pit

Sludge accumulation and methanogenic activity in an anaerobic lagoon

2000 ◽  
Vol 42 (10-11) ◽  
pp. 247-255 ◽  
Author(s):  
J. Paing ◽  
B. Picot ◽  
J. P. Sambuco ◽  
A. Rambaud
Keyword(s):  
Anaerobic Digestion ◽  
Methane Production ◽  
Anaerobic Degradation ◽  
Volatile Fatty Acids ◽  
Anaerobic Fermentation ◽  
Methanogenic Activity ◽  
Start Up ◽  
Anaerobic Lagoon ◽  
Methane Production Rate ◽  
Sludge Accumulation

Sludge accumulation and the characteristics of anaerobic digestion in sludge had been investigated in a primary anaerobic lagoon. Methanogenic potential of sludge was evaluated by an anaerobic digestion test which measured the methane production rate. Sludge was sampled at several points in the lagoon to determine spatial variations and with a monthly frequency from the start-up of the lagoon to observe the development of anaerobic degradation. Maximum amounts of sludge accumulated near the inlet. The mean methane production of sludge was 2.9 ml gVS–1 d–1. Sludge near the outlet presented a greater methanogenic activity and a lesser concentration of volatile fatty acids than near the inlet. The different stages of anaerobic degradation were spatially separated, acidogenesis near the inlet and methanogenesis near the outlet. This staged distribution seemed to increase efficiency of anaerobic fermentation compared with septic tanks. Methane release at the surface of the lagoon was estimated to be very heterogeneous with a mean of 25 l m–2 d–1. The development of performance and sludge characteristics showed the rapid beginning of methanogenesis, three months after the start-up of the anaerobic lagoon. Considering the volume of accumulated sludge, it could however be expected that methanogenic activity would further increase.

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