Comparing thermal conditions inside and outside lactating dairy cattle barns in Canada.

The health, longevity, and performance of dairy cattle can be adversely affected by heat stress. This study evaluated the in-barn condition [i.e.

Perspectives on peak liquid manure temperature with implications for methane emissions.

Methane emissions from liquid manure storage are currently estimated with a methane conversion factor (MCF) based on manure temperature inputs or air temperatures as a substitute in the 2019 IPCC Tier 2 method. However, differences between peak manure temperature and peak air temperature (T ) in warm seasons are likely to occur and result in poor estimates of MCF and methane emissions. To address this concern, this study aims to investigate the relationship between the T and ratio of manure surface area to manure volume (R ) using a mechanistic model and by analyzing farm-scale measurement studies across Canada.

Distribution of livestock sectors in Canada: Implications for manureshed management.

Canada's livestock production and human populations are concentrated in southern regions. Understanding spatial and temporal distributions of animals and excreted nutrients is key to optimizing manure resources and minimizing impact of livestock. Here, we identify manureshed concerns and opportunities by reconciling nitrogen supply and demand on a regional and national scale.

Fugitive methane emissions from two agricultural biogas plants.

This study quantified fugitive methane (CH) losses from multiple sources (open digestate storages, digesters and flare) at two biogas facilities over one year, providing a much needed dataset integrating all major loss pathways and changes over time. Losses of CH from Facility A were primarily from digestate storage (5.8% of biogas CH), followed by leakage/venting (5.

Evaluating the 2019 IPCC refinement for estimating methane conversion factors in Canada.

Methane emissions from liquid manure management in Canada are an important greenhouse gas source. A wide range of seasonal temperatures, distribution of livestock farms, and various management practices in Canada means that regional methane conversion factors (MCF) that account for spatially discrete climate and management should be used. This study explores the impacts of using the 2019 IPCC Refinement methodology on estimates of MCFs across Canada.

A mechanistic model of methane emission from animal slurry with a focus on microbial groups.

Liquid manure (slurry) from livestock releases methane (CH4) that contributes significantly to global warming. Existing models for slurry CH4 production-used for mitigation and inventories-include effects of organic matter loading, temperature, and retention time but cannot predict important effects of management, or adequately capture essential temperature-driven dynamics. Here we present a new model that includes multiple methanogenic groups whose relative abundance shifts in response to changes in temperature or other environmental conditions.

Understanding methane emission from stored animal manure: A review to guide model development.

National inventories of methane (CH ) emission from manure management are based on guidelines from the Intergovernmental Panel on Climate Change using country-specific emission factors. These calculations must be simple and, consequently, the effects of management practices and environmental conditions are only crudely represented in the calculations. The intention of this review is to develop a detailed understanding necessary for developing accurate models for calculating CH emission from liquid manure, with particular focus on the microbiological conversion of organic matter to CH .

Regional climate influences manure temperature and methane emissions - A pan-Canadian modelling assessment.

This study explores the variation of liquid manure temperature (T) and CH emissions associated with contrasting regional climates, inter-annual weather variation, and manure storage emptying. As a case-study, six regions across Canada were used, spanning 11°32' latitude and 58°30' longitude. Annual average air temperatures ranged from 3.

Does overwintering change the inoculum effect on methane emissions from stored liquid manure?

Greenhouse gas (GHG) emissions, especially methane (CH ), from manure storage facilities can be substantial. Methane production requires adapted microbial communities ("inoculum") to be present in the manure. Complete removal of liquid dairy manure (thus removing all inoculum) from storage tanks in the spring has been shown to significantly reduce CH emissions over the following warm season.

Increased dairy farm methane concentrations linked to anaerobic digester in a five-year study.

Organic waste materials are sources of anthropogenic methane (CH ) emissions. Anaerobic digestion (AD) is a technology that produces biogas from organic waste materials, and CH is the primary component of biogas. Unintended emission of CH from biogas facilities could undercut the environmental benefits of this technology.

Towards an improved methodology for modelling climate change impacts on cropping systems in cool climates.

Assessment of the impact of climate change on agricultural sustainability requires a robust full system estimation of the interdependent soil-plant-atmospheric processes coupled with dynamic farm management. The simplification or exclusion of major feedback mechanisms in modelling approaches can significantly affect model outcomes. Using a biogeochemical model, DNDCv.

Effects of Two Manure Additives on Methane Emissions from Dairy Manure.

Liquid manure is a significant source of methane (CH), a greenhouse gas. Many livestock farms use manure additives for practical and agronomic purposes, but the effect on CH emissions is unknown. To address this gap, two lab studies were conducted, evaluating the CH produced from liquid dairy manure with Penergetic-g (12 mg/L, 42 mg/L, and 420 mg/L) or AgrimestMix (30.

Dairy manure acidification reduces CH4 emissions over short and long-term.

Acidification with sulphuric acid and cleaning residual manure in tanks are promising practices for reducing methane (CH), which is a potent greenhouse gas. To date, no data are available on CH reductions from acidifying only residual manure (rather than all manure). Moreover, long-term effects of manure acidification (i.

Greenhouse Gas Mitigation through Dairy Manure Acidification.

Liquid dairy manure storages are sources of methane (CH), nitrous oxide (NO), and ammonia (NH) emissions. Both CH and NO are greenhouse gases (GHGs), whereas NH is an indirect source of NO emissions. Manure acidification is a strategy used to reduce NH emissions from swine manure; however, limited research has expanded this strategy to reducing CH and NO emissions by acidifying dairy manure.

Assessing the Impacts of Climate Variability on Fertilizer Management Decisions for Reducing Nitrogen Losses from Corn Silage Production.

There is an incentive for dairy farmers to maximize crop production while minimizing costs and environmental impacts. In cold climates, farmers have limited opportunity to balance field activities and manure storage requirements while limiting nutrient losses. A revised DeNitrification DeComposition (DNDC) model for simulating tile drainage was used to investigate fertilizer scenarios when applying dairy slurry or urea on silage corn ( L.

Intermittent agitation of liquid manure: effects on methane, microbial activity, and temperature in a farm-scale study.

Liquid manure storages are a significant source of methane (CH) emissions. Farmers commonly agitate (stir) liquid manure prior to field application to homogenize nutrients and solids. During agitation, manure undergoes mechanical stress and is exposed to the air, disrupting anaerobic conditions.

Reduction in Methane Emissions From Acidified Dairy Slurry Is Related to Inhibition of Species.

Liquid dairy manure treated with sulfuric acid was stored in duplicate pilot-scale storage tanks for 120 days with continuous monitoring of CH emissions and concurrent examination of changes in the structure of bacterial and methanogenic communities. Methane emissions were monitored at the site using laser-based Trace Gas Analyzer whereas quantitative real-time polymerase chain reaction and massively parallel sequencing were employed to study bacterial and methanogenic communities using 16S rRNA and methyl-coenzyme M Reductase A () genes/transcripts, respectively. When compared with untreated slurries, acidification resulted in 69-84% reductions of cumulative CH emissions.

Sodium Persulfate and Potassium Permanganate Inhibit Methanogens and Methanogenesis in Stored Liquid Dairy Manure.

Stored liquid dairy manure is a hotspot for methane (CH) emission, thus effective mitigation strategies are required. We assessed sodium persulfate (NaSO), potassium permanganate (KMnO), and sodium hypochlorite (NaOCl) for impacts on the abundance of microbial communities and CH production in liquid dairy manure. Liquid dairy manure treated with different rates (1, 3, 6, and 9 g or mL L slurry) of these chemicals or their combinations were incubated under anoxic conditions at 22.

Long-term Trends in Corn Yields and Soil Carbon under Diversified Crop Rotations.

Agricultural practices such as including perennial alfalfa ( L.), winter wheat ( L.), or red clover ( L.

Quantifying greenhouse gas emissions from municipal solid waste dumpsites in Cameroon.

Open dumpsites that receive municipal solid waste are potentially significant sources of greenhouse gas (GHG) emissions into the atmosphere. There is little data available on emissions from these sources, especially in the unique climate and management of central Africa. This research aimed at quantifying CH, NO and CO emissions from two open dumpsites in Cameroon, located in Mussaka-Buea, regional headquarters of the South West Region and in Mbellewa-Bamenda, regional headquarters of the North West Region.

On the systematic underestimation of methane conversion factors in IPCC guidance.

This paper documents a systematic underestimation in how the Tier 2 methane conversion factors (MCF) are calculated in IPCC (2006) guidelines for liquid manure management. The first issue is the use of annual average temperature as an input to a non-linear function describing methane production. As expected based on Jensen's inequality, the MCF calculated based on annual average temperature is always an underestimate.

Targeting Bacteria and Methanogens To Understand the Role of Residual Slurry as an Inoculant in Stored Liquid Dairy Manure.

Microbial communities in residual slurry left after removal of stored liquid dairy manure have been presumed to increase methane emission during new storage, but these microbes have not been studied. While actual manure storage tanks are filled gradually, pilot- and farm-scale studies on methane emissions from such systems often use a batch approach. In this study, six pilot-scale outdoor storage tanks with (10% and 20%) and without residual slurry were filled (gradually or in batch) with fresh dairy manure, and methane and methanogenic and bacterial communities were studied during 120 days of storage.

Characterizing the Performance of Gas-Permeable Membranes as an Ammonia Recovery Strategy from Anaerobically Digested Dairy Manure.

Capturing ammonia from anaerobically digested manure could simultaneously decrease the adverse effects of ammonia inhibition on biogas production, reduce reactive nitrogen (N) loss to the environment, and produce mineral N fertilizer as a by-product. In this study, gas permeable membranes (GPM) were used to capture ammonia from dairy manure and digestate by the diffusion of gaseous ammonia across the membrane where ammonia is captured by diluted acid, forming an aqueous ammonium salt. A lab-scale prototype using tubular expanded polytetrafluoroethylene (ePTFE) GPM was used to (1) characterize the effect of total ammonium nitrogen (TAN) concentration, temperature, and pH on the ammonia capture rate using GPM, and (2) to evaluate the performance of a GPM system in conditions similar to a mesophilic anaerobic digester.

Potential methane emission reductions for two manure treatment technologies.

The effect of two dairy manure treatments, solid-liquid separation (SLS) and anaerobic digestion (AD), on methane potential and the speed of production was evaluated. Assays were performed in the lab to measure methane (CH) production over 202 d from dairy manure samples taken before and after each treatment. Compared to raw manure, CH emissions on a per-L basis were reduced 81% by SLS and 59% by AD, on average.