Greenhouse gas emissions from agroecosystems in Western Canada

How we can reduce losses from beef cattle production systems

How we can reduce losses through land and nitrogen fertilizer management


Background - the main greenhouse gases in agriculture

The three major greenhouse gases are carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Agricultural practices can also create carbon dioxide sinks and store carbon. On a national scale, agriculture currently contributes about 8% (60Mt CO2 eq.) of our total greenhouse gas emissions, according to Environment Canada’s 2015 National Inventory Report. Both cropland and livestock generate all three gases in varying amounts, depending on operation type, production environment (e.g. soil type, climate, weather) and management practices. Cropland agriculture contributes 40% and livestock agriculture about 60% of the total agriculture-related emissions in Canada. In Manitoba, the relative contribution from each sector is similar at 49% and 51% of total agriculture emissions (6.7 Mt CO2 eq.) for livestock and cropland, respectively.

Like throwing money into the air - Greenhouse gas losses from agriculture equate to money lost. Enteric methane is energy that could have been converted to milk or muscle in cattle. Nitrous oxide is the loss of nitrogen originating from soils, manures, and fertilizers, making it no longer available for plant uptake. Nitrogen is an essential protein building block in plants and animals, and photosynthesis would not be possible without it. Feed and fertilizer are two of the biggest input costs in agriculture. Management practices that retain feed for animal energy and nitrogen as fertilizer for plant uptake, rather than expelling them as methane or nitrous oxide equates to money spent on increased productivity rather than contributing to climate change. In addition, loss of soil carbon increases atmospheric carbon dioxide concentrations, which causes global warming, and reduces the fertility, soil water holding ability, and health of the soil.

Key Messages from Research

Cropping Systems

  • Enhanced efficiency urea can decrease nitrous oxide emissions by about 50% compared to conventionally broadcasted urea for early season wet and warm eastern Prairie conditions, indicating that changing the fertilizer source can decrease greenhouse gas emissions
  • Late-fall application of anhydrous ammonia prior to freeze-up can reduce N2O emissions from clay soil in cold climates compared to spring application.
  • Annual crops cause a carbon loss (carbon dioxide emissions) whereas perennial crops are usually carbon sinks (carbon dioxide uptake) in the eastern Prairies.
  • Perennial forages like alfalfa can decrease nitrous oxide emissions by 75% compared to annual crops.
  • Beef Cattle Systems

  • Cattle can lose up to 1 in 10 bales worth of feed energy as methane when digesting low quality hay and are less efficient
  • Feeding cattle forages harvested at optimum maturity maximizes digestible energy content and has the potential to reduce methane emissions by 8% (when crude protein is increased from 6.9 to 13.6%)
  • Covering or shedding hay can reduce dry matter losses of between 5 and 35%, depending on the amount of precipitation, storage site and original bale condition
  • Well managed perennial grasslands remove carbon from the air and store it in soil as root material (carbon sequestration)
  • Culling the breeding herd based on breeding soundness of bulls and cows will maintain a fertile and high producing herd, improving production efficiency and reducing feed costs
  • Development of a sound ration program to deliver required nutrients based on age and weight of animals will maintain a healthy and productive calf crop
  • Resources for producers - Beneficial Management Practices Factsheets

    Land and crop rotation management

  • Preservation of Perennial Forage Lands In The Eastern Prairies 
  • Nitrogen fertilizer management

  • Reduction of Nitrous Oxide (N2O) Emissions In Irrigated Potato In Manitoba
  • Selecting The Right Placement Of Fertilizer N In Manitoba
  • Selecting The Right Source Of Fertilizer N In Manitoba
  • Cattle production management

  • Optimizing Feed and Forage Quality
  • Decreasing Emissions and Increasing Production Efficiency of Beef Cattle
  • Resources for Student Educators

  • Learning materials and programming on GHG emissions in agroecosystems and mitigation
  • Agricultural Greenhouse Gases Research Publications

  • Land and crop rotation management
  • Nitrogen fertilizer management (synthetic and manure)
  • Cattle production management
  • Modelling greenhouse gas emissions from agroecosystems
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    Funding for this research was provided in part by the Government of Canada through the Agricultural Greenhouse Gases Program of Agriculture and Agri-Food Canada.

     

     

    AGGP 1 - Project Duration: 2011-2016.

    Research Program Overview

     Quick link to GHG BMP Factsheets:

     

  • Optimizing Feed and Forage Quality
  • Decreasing Emissions and Increasing Production Efficiency of Beef Cattle
  • Preservation of Perennial Forage Lands In The Eastern Prairies 

  • Reduction of Nitrous Oxide (N2O) Emissions In Irrigated Potato In Manitoba
  • Selecting The Right Placement Of Fertilizer N In Manitoba
  • Selecting The Right Source Of Fertilizer N In Manitoba
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     AGGP 2 - Project Duration: 2016 - 2021

    Research Program Overview