scholarly journals Methanogenesis from forages fed to sheep

2002 ◽  
pp. 167-171 ◽  
Author(s):  
G.C. Waghorn ◽  
M.H. Tavendale ◽  
D.R. Woodfield
Keyword(s):  
Greenhouse Gas ◽  
Methane Production ◽  
Condensed Tannin ◽  
Ghg Emissions ◽  
Red Clover ◽  
Methane Emissions ◽  
Future Research ◽  
Feeding Value ◽  
Metabolisable Energy ◽  
Lotus Pedunculatus

Methane production has been measured from lambs fed contrasting forages. This work has been driven by the need to reduce greenhouse gas emissions from agriculture and to determine energy losses to methane from contrasting diets. Young ram lambs were fed either fresh ryegrass/white clover pasture, lucerne (also pelleted lucerne), sulla, chicory, red clover, Lotus pedunculatus (lotus) and mixtures of sulla and lucerne, sulla and chicory and chicory with red clover. The effects of condensed tannin (CT) in lotus on methane production were also measured. The trials were carried out indoors with sheep held in metabolism crates to enable an accurate measurement of intake and digestibility as well as methane production. Principal findings were a two-fold range in emissions from 11.5g CH4/kg dry matter intake (DMI) with lotus to 25.7g CH4/kg DMI with pasture and a 16% reduction in methane production due to the CT in lotus. This range in emissions from good quality forages represents a loss of about 7-11% of metabolisable energy and presents a clear direction for future research to better utilise the feeding value of pastures and reduce greenhouse gas (GHG) emissions from agriculture. High quality perennial forages should be used where practical, and researchers need to identify plant parameters responsible for the variation in methane emissions. Research must focus on rapid passage of digesta through the rumen of grazing animals and will involve manipulation of the fibre content of grasses. Introduction of CT into diets is a likely target to reduce methane production. Improving the rapidly digestible constituents of forages is another opportunity, but difficult to target. Keywords: condensed tannins, forage quality, forages, greenhouse gases, methane emissions, sheep

Effect of low and high forage diet on enteric and manure pack greenhouse gas emissions from a feedlot

2004 ◽  
Vol 84 (3) ◽  
pp. 445-453 ◽  
Author(s):  
D. A. Boadi ◽  
K. M. Wittenberg ◽  
S. L. Scott ◽  
D. Burton ◽  
K. Buckley ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Methane Production ◽  
Sulfur Hexafluoride ◽  
Ghg Emissions ◽  
Sampling Period ◽  
Beef Steers ◽  
Enteric Fermentation ◽  
Gross Energy ◽  
Isocaloric Diets ◽  
Dietary Treatments

The objectives of this study were to assess enteric methane (CH4) production by beef steers fed one of two isocaloric diets with different forage:grain ratios and to quantify greenhouse gas (GHG) emissions from bedded manure packs in the eight feedlot pens holding these steers (14 head pen-1). Five animals (252 ± 20 kg) in each pen were randomly selected for measurement of CH4 emissions over the course of the 126-d feeding trial. Two 24-h gas collections were completed for each steer in each of three collection periods using the sulfur hexafluoride tracer gas technique. The fluxes of nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) from bedding packs were measured using vented static chambers in each sampling period. Methane production (L d-1) was 42% higher (P < 0.05) from steers fed the low forage:grain ratio than from steers fed the high forage:grain ratio. Overall, methane production (% of gross energy intake) ranged from 0.9 to 6.9% on the low forage:grain diet and from 0.7 to 4.9% on the high forage:grain diet. Daily CH4 emissions were similar in the first two periods and increased during the third sampling period. There was no effect of diet on manure pack temperature during sampling, however, the manure pack was deeper (P < 0.05) in pens holding animals fed the high forage:grain diet. Furthermore, diet had no effect on the manure pack fluxes. Total daily non-CO2 emissions from enteric and manure pack sources (CO2 equivalent) were different (P < 0.05) between dietary treatments and averaged 1931 ± 81 g head-1 d-1 for the low forage:grain and 1394 ± 81 g head-1 d-1 for the high forage:grain diet. Key words: Feedlot steers, greenhouse gases, enteric fermentation, manure packs

Decrease in methane emissions in dairy cows with increase in dietary linseed content

2009 ◽  
Vol 2009 ◽  
pp. 21-21 ◽  
Author(s):  
C Martin ◽  
A Ferlay ◽  
Y Chilliard ◽  
M Doreau
Keyword(s):  
Dairy Cows ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Dietary Fat ◽  
Methane Production ◽  
Significant Contribution ◽  
Methane Emissions ◽  
Dietary Manipulation ◽  
Maize Silage ◽  
Promising Solution

Because ruminants make a significant contribution to greenhouse gas emissions, attempts are being made by dietary manipulation, to mitigate methane emissions without altering animal performance. Dietary fat supply may be a promising solution (Martin et al., 2008a). A first experiment has shown that increasing extruded linseed supply in a hay-based diet resulted in a decrease in methane production (Martin et al., 2007). A second experiment has been carried out using a maize silage-based diet and the same linseed supply. The present abstract summarises the results of both experiments.

scholarly journals Integrating BIM with greenhouse-gas emissions in AEC: A scientometric review

2020 ◽  
Vol 143 ◽  
pp. 01008
Author(s):  
Mengyun Li ◽  
Kun Lu ◽  
Hongyu Wang ◽  
Sai Wang
Keyword(s):  
Greenhouse Gas ◽  
Ghg Emissions ◽  
Development Trend ◽  
Status Quo ◽  
Information Modeling ◽  
Future Research ◽  
Systematic Analysis ◽  
Building Information ◽  
The Development Trend ◽  
Calculation Analysis

More and more attention has been paid to the application of Building Information Modeling (BIM) in the field of greenhouse-gas (GHG) emissions in Architecture, Engineering and Construction (AEC). However, systematic analysis and visualization of its development trend have not been carried out. This paper combined digital statistical method and scientometrics to analyse major documents published in the Scopus database from 2008 to September 2019 and discussed the development trend, the main journals co-citation and keywords co-occurrence of this field. And then main challenges and future research were summarized by content analysis. The results show that: (1) the number of articles related to integrating BIM with GHG emissions has increased significantly in AEC, which deserves more and more scholars to study in this field; (2) top cited journals mainly focus on built environment, BIM and clean technology; (3) BIM and Life Cycle Assessment (LCA) are the mainstream issues in the calculation, analysis and decisionmaking of GHG emissions. This review provides status quo and existing main challenges of knowledge system of BIM applied to GHG emissions in AEC, and also offers inspiration for future research.

Temporal and Spatial Variability of Methane Emissions from Texas Open-Lot Beef Cattle Feedyard Pens

2021 ◽  
Vol 64 (6) ◽  
pp. 1781-1794
Author(s):  
David B. Parker ◽  
Kenneth D. Casey ◽  
Heidi Maria Waldrip ◽  
Byeng Min ◽  
Bryan L. Woodbury ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Greenhouse Gas ◽  
Pore Space ◽  
Ghg Emissions ◽  
Warm Season ◽  
Methane Emissions ◽  
Cool Season ◽  
Ch4 Flux ◽  
Before And After ◽  
Temporal And Spatial

HighlightsOpen-lot beef cattle feedyards are a source of greenhouse gas emissions.Pen surface methane emissions were quantified during the cool and warm seasons.Methane was generated in the lower anaerobic layers of the manure pack.Methane emissions decreased after rainfall due to methane oxidation or blocking of pore space.Pen surface methane emissions accounted for &lt;1% of overall feedyard GHG as CO2eq.Abstract. Texas is one of the top beef-producing states, where annually more than five million beef cattle are finished in large feedyards on earthen-surfaced pens. Manure deposited on open-lot pen surfaces can contribute to greenhouse gas (GHG) emissions such as methane (CH4). Two week-long sampling campaigns were conducted in April (cool season) and August (warm season) to quantify CH4 emissions from the feedyard pen surface. Emissions were monitored before and after 12.7 mm simulated rainfall events. Temporal and spatial variabilities in emissions were quantified using automated recirculating flux chambers, a multiplexer system, and a real-time CH4 analyzer. During the cool season, mean CH4 flux was 1.09 (SD ±2.39) and 0.12 (±0.25) g animal-1 d-1 before and after rainfall, respectively. During the warm season, mean CH4 flux was 0.65 (±1.01) and 0.26 (±0.44) g animal-1 d-1 before and after rainfall, respectively. This suggested that CH4 was produced in the lower, anaerobic layer of the manure pack and CH4 emissions were inhibited following rainfall, most likely due to microbial oxidation of CH4 in the upper layers through methanotrophy or from slowing of diffusion by blocking the manure pore space. The overall mean pen surface CH4 flux was 0.53 g animal-1 d-1. This flux accounted for a small percentage (&lt;1%) of the overall estimated feedyard GHG emissions expressed as CO2eq. Thus, efforts to mitigate GHG from open-lot beef cattle feedyards in the Texas Panhandle should focus on sources with higher percentages of overall GHG, such as enteric methane, pen surface nitrous oxide, and nitrous oxide from fertilized cropland. Keywords: Beef cattle, Flux chamber, Greenhouse gas, Manure, Methane, Rainfall.

scholarly journals Water level, vegetation composition, and plant productivity explain greenhouse gas fluxes in temperate cutover fens after inundation

2016 ◽  
Vol 13 (13) ◽  
pp. 3945-3970 ◽  
Author(s):  
Merten Minke ◽  
Jürgen Augustin ◽  
Andrei Burlo ◽  
Tatsiana Yarmashuk ◽  
Hanna Chuvashova ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Water Level ◽  
Phragmites Australis ◽  
Land Surface ◽  
Ghg Emissions ◽  
Typha Latifolia ◽  
Methane Emissions ◽  
Co2 Uptake ◽  
Vegetation Composition ◽  
Flooded Areas

Abstract. Peat extraction leaves a land surface with a strong relief of deep cutover areas and higher ridges. Rewetting inundates the deep parts, while less deeply extracted zones remain at or above the water level. In temperate fens the flooded areas are colonized by helophytes such as Eriophorum angustifolium, Carex spp., Typha latifolia or Phragmites australis dependent on water depth. Reeds of Typha and Phragmites are reported as large sources of methane, but data on net CO2 uptake are contradictory for Typha and rare for Phragmites. Here, we analyze the effect of vegetation, water level and nutrient conditions on greenhouse gas (GHG) emissions for representative vegetation types along water level gradients at two rewetted cutover fens (mesotrophic and eutrophic) in Belarus. Greenhouse gas emissions were measured campaign-wise with manual chambers every 2 to 4 weeks for 2 years and interpolated by modelling. All sites had negligible nitrous oxide exchange rates. Most sites were carbon sinks and small GHG sources. Methane emissions generally increased with net ecosystem CO2 uptake. Mesotrophic small sedge reeds with water table around the land surface were small GHG sources in the range of 2.3 to 4.2 t CO2 eq. ha−1 yr−1. Eutrophic tall sedge – Typha latifolia reeds on newly formed floating mats were substantial net GHG emitters in the range of 25.1 to 39.1 t CO2 eq. ha−1 yr. They represent transient vegetation stages. Phragmites reeds ranged between −1.7 to 4.2 t CO2 eq. ha−1 yr−1 with an overall mean GHG emission of 1.3 t CO2 eq. ha−1 yr−1. The annual CO2 balance was best explained by vegetation biomass, which includes the role of vegetation composition and species. Methane emissions were obviously driven by biological activity of vegetation and soil organisms. Shallow flooding of cutover temperate fens is a suitable measure to arrive at low GHG emissions. Phragmites australis establishment should be promoted in deeper flooded areas and will lead to moderate, but variable GHG emissions or even occasional sinks. The risk of large GHG emissions is higher for eutrophic than mesotrophic peatlands. Nevertheless, flooding of eutrophic temperate fens still represents a safe GHG mitigation option because even the hotspot of our study, the floating tall sedge – Typha latifolia reeds, did not exceed the typical range of GHG emissions from drained fen grasslands and the spatially dominant Phragmites australis reed emitted by far less GHG than drained fens.

scholarly journals Greenhouse gas disclosures by Chinese power companies: trends, content and strategies

2017 ◽  
Vol 13 (3) ◽  
pp. 331-358 ◽  
Author(s):  
Mahmood Ahmed Momin ◽  
Deryl Northcott ◽  
Mohammed Hossain
Keyword(s):  
Greenhouse Gas ◽  
Ghg Emissions ◽  
Reputation Management ◽  
Annual Reports ◽  
Future Research ◽  
Chinese Government ◽  
Content Type ◽  
Management Objectives ◽  
Corporate Social ◽  
Practical Implications

Purpose This paper aims to investigate the greenhouse gas (GHG)-related disclosure trends, content and strategies of the eight most high GHG-emitting Chinese power companies, over a period when government pressure to manage GHG emissions increased. Design/methodology/approach Data were collected from the 2000-2009 annual reports, corporate social and environmental responsibility reports and websites of eight Chinese power companies. Content analysis results were supplemented with excerpts from documents written in English or Chinese. Legitimacy theory informed the interpretation of the findings. Findings GHG-related disclosures increased from 2002 when the Chinese Government ratified the Kyoto Protocol and promulgated stringent environmental regulations. However, some expected types of GHG-related disclosure were absent or rare. Disclosure practices were found to be underpinned by reputation management objectives and reflected a symbolic rather than substantive legitimation strategy. Research limitations/implications This study extends the literature on GHG-related disclosures by carbon-intensive firms and points to the need for future research to examine such disclosures in different countries to appreciate the variety in practice. Practical implications While the Chinese Government appears to have driven the emergence of GHG-related disclosure practices, companies can effect improvement by expanding the scope and content of what they disclose. Also, the growing emphasis on website disclosures may present challenges in ensuring the reliability and assurance of GHG disclosures. Originality/value This is the first study to examine GHG-related disclosure practices by Chinese power-generating companies, a sector crucial to managing the GHG effects of China’s significant economic growth.

scholarly journals Overview of nutritional strategies to lower enteric methane emissions in ruminants

2012 ◽  
pp. 1-7 ◽  
Author(s):  
Alireza Bayat ◽  
Kevin J. Shingfield
Keyword(s):  
Organic Acids ◽  
Milk Production ◽  
Methane Production ◽  
Ghg Emissions ◽  
Methane Emissions ◽  
Enteric Methane ◽  
Reducing Bacteria ◽  
Enteric Methane Emissions

Since ruminants are capable of utilizing fibrous feeds not digested by mono-gastrics, they represent a valuable natural resource for meeting future increases in global food supply. Ruminants have both local (nitrogen and phosphorus pollutions) and global (greenhouse gases, GHG) environmental footprints. It is estimated that the livestock sector is responsible for 18% of global anthropogenic GHG emissions. Losses of methane represent 30 to 50% of total GHG from livestock production, with the contribution from ruminants accounting for about 80%. Due to the concerns of increases in GHG emissions into the environment and potential effects on global warming, there is a need to develop strategies to lower methane emissions from ruminants as part of an overall requirement to improve the sustainability of ruminant food production systems. Methane is produced as a by-product of anaerobic fermentation in the reticulo-rumen, largely due to the activity of methanogenic archaea. Recent research has focused on the potential of novel feed ingredients (probiotics, ionophores, acetogen-based inoculants, bacteriocins, organic acids and plant extracts) or vaccines to lower hydrogen production and/or increase the transfer and utilization of metabolic hydrogen in the production of end-products other than methane in the rumen. Research to date has provided evidence that dietary supplements of plant or marine oils, oilseeds, specific fatty acids and condensed tannins, as well as defaunation, increases in production level or decreases in the proportion of forage in the diet may lower enteric methane production. Even though dietary lipid supplements can be used to lower methane output, in high amounts a decrease in intake and milk production can be expected. While further investigations have demonstrated the efficacy of specific agents on methanogenesis in vitro, the effects have not been substantiated in vivo. Altering the ratio of H2 /non-H2 producing fibrolytic bacteria to lower methanogenesis without altering fibre digestion has been demonstrated under experimental conditions. Furthermore, non-H2 producing communities have been characterized in the digesta of certain ruminant species. In contrast, stimulating acetogenesis by inoculation with rumen acetogens or non-rumen acetogens have met with limited success in vitro and in vivo. Research has also concentrated on stimulating the ultilisation of metabolic hydrogen by sulphate reducing bacteria, but there remains concern over the toxicity of H2S in the host ruminant. Investigations of nitrate reducing bacteria which produce more NH3 and less toxic nitrite, have indicated promising results. Increasing the number of capnophilic bacteria which use CO2 and H2 to produce organic acids, succinic acid in particular, may decrease methane production. In isolation, several approaches have been shown to decrease enteric methane emissions, but often part of the changes observed are related to lowered organic matter digestion in the rumen. However, lowering methane production per unit product over the lifetime of an animal should be regarded as the central goal to decrease GHG from ruminant livestock systems. This highlights the need for integrated solutions to improve digestive efficiency, as well as fertility and health. In conclusion, any prospective solution to lower on-farm GHG emissions must be practical, cost effective and have no adverse effect on the profitability of ruminant meat and milk production. Recent research has indicated significant potential, but none of the strategies tested thus far satisfy all of the necessary criteria for immediate implementation.

Methylotrophic methanogens everywhere — physiology and ecology of novel players in global methane cycling

2019 ◽  
Vol 47 (6) ◽  
pp. 1895-1907 ◽  
Author(s):  
Andrea Söllinger ◽  
Tim Urich
Keyword(s):  
Greenhouse Gas ◽  
Methanogenic Archaea ◽  
Methane Emissions ◽  
Model System ◽  
Anthropogenic Sources ◽  
Future Research ◽  
Ecological Studies ◽  
Methane Cycling ◽  
Ruminant Animals

Research on methanogenic Archaea has experienced a revival, with many novel lineages of methanogens recently being found through cultivation and suggested via metagenomics approaches, respectively. Most of these lineages comprise Archaea (potentially) capable of methanogenesis from methylated compounds, a pathway that had previously received comparably little attention. In this review, we provide an overview of these new lineages with a focus on the Methanomassiliicoccales. These lack the Wood–Ljungdahl pathway and employ a hydrogen-dependent methylotrophic methanogenesis pathway fundamentally different from traditional methylotrophic methanogens. Several archaeal candidate lineages identified through metagenomics, such as the Ca. Verstraetearchaeota and Ca. Methanofastidiosa, encode genes for a methylotrophic methanogenesis pathway similar to the Methanomassiliicoccales. Thus, the latter are emerging as a model system for physiological, biochemical and ecological studies of hydrogen-dependent methylotrophic methanogens. Methanomassiliicoccales occur in a large variety of anoxic habitats including wetlands and animal intestinal tracts, i.e. in the major natural and anthropogenic sources of methane emissions, respectively. Especially in ruminant animals, they likely are among the major methane producers. Taken together, (hydrogen-dependent) methylotrophic methanogens are much more diverse and widespread than previously thought. Considering the role of methane as potent greenhouse gas, resolving the methanogenic nature of a broad range of putative novel methylotrophic methanogens and assessing their role in methane emitting environments are pressing issues for future research on methanogens.

Determinants of greenhouse gas assurance provider choice

2017 ◽  
Vol 25 (1) ◽  
pp. 114-135 ◽  
Author(s):  
Wendy Green ◽  
Stuart Taylor ◽  
Jennifer Wu
Keyword(s):  
Greenhouse Gas ◽  
Design Methodology ◽  
Ghg Emissions ◽  
Future Research ◽  
Relative Importance ◽  
Accounting Firms ◽  
Content Type ◽  
Provider Choice ◽  
Geographical Dispersion ◽  
Practical Implications

Purpose This paper surveys corporate officers responsible for greenhouse gas (GHG) reporting and assurance to determine the attributes that influence their choice between an accounting and a non-accounting GHG assurance provider. Differences in the relative importance of these attributes between those selecting accounting and non-accounting assurers are also explored. Design/methodology/approach A survey questionnaire was completed by 25 corporate officers responsible for reporting and voluntarily assurance of GHG emissions in Australia. The questionnaire asked the respondents to indicate the relative importance of 41 company and assurer attributes in influencing their assurance provider choice. Findings Results indicate that attributes related to the assurance provider, such as team and team leader assurance knowledge, reputation, objectivity and independence, are more influential than attributes related to the nature of the company or the nature of the GHG emissions. Attributes such as geographical dispersion of operations were found to be differently important to this decision between companies purchasing assurance from accounting and non-accounting firms. Research limitations/implications The study’s main limitation is the small number of participants. Future research may extend this study by exploring the conditions under which companies voluntarily assure GHG emissions as well the motivations of responsible officers in their assurer choice. Practical implications This paper provides valuable insights to GHG assurers to assist their understanding of the attributes that are important to potential GHG assurance clients. Originality/value The study makes unique contributions to the assurer choice literature by not only addressing this issue in the context of the dichotomous GHG assurance market but also by addressing it from the perspective of the assurance purchaser.

scholarly journals Technology choices in scaling up sanitation can significantly affect greenhouse gas emissions and the fertiliser gap in India

2017 ◽  
Vol 7 (3) ◽  
pp. 466-476 ◽  
Author(s):  
Michal Kulak ◽  
Nimish Shah ◽  
Niteen Sawant ◽  
Nicole Unger ◽  
Henry King
Keyword(s):  
Greenhouse Gas ◽  
Source Separation ◽  
Ghg Emissions ◽  
Scaling Up ◽  
Future Research ◽  
Batch Reactors ◽  
Nitrogen And Phosphorus ◽  
Available Nitrogen ◽  
Large Variability ◽  
Country Level

Nearly 800 million people in India lack access to adequate sanitation. The choice of technology for addressing this need may have important sustainability implications. In this study, we used life cycle assessment to compare environmental impacts and nutrient recovery potentials of four different options for providing everyone in India with access to improved sanitation: (i) centralised wastewater treatment with sequential batch reactors (SBR), (ii) twin-pit latrines, (iii) latrines with source separation only and (iv) latrines with source-separation of urine and faeces connected to biogas plants. Results revealed large variability. Closing the sanitation gap through pit latrines would be expected to cause large increases of India's annual greenhouse gas (GHG) emissions, equivalent to 7% of current levels. Source separation only and centralised plants with SBR will be associated with lower GHG emissions, while the biogas scenario shows a potential to provide net emission reduction. The study revealed that source separating systems can provide significant quantities of plant available nitrogen and phosphorus at the country level. Future research should include more technological options and regions. Methodology piloted in this study can be integrated into the planning and design processes for scaling up sanitation in India and other countries.

Sign in / Sign up

Export Citation Format

Share Document