Assessing greenhouse gas (GHG) emissions from beef production using the Holos software was the focus of a third annual Holos workshop, held recently in Airdrie, Alta.
GHG emissions and carbon footprints are a major focus within the industry today as consumers demand information about how their food is produced. A concern that this growing pressure may push producers into ill-informed decisions that would have an impact on long-term environmental and economic performance is why Agriculture and Agri-Food Canada (AAFC) developed the Holos GHG software 10 years ago.
The beef cattle industry is important to the Canadian economy contributing $13 billion in 2011 to the gross domestic product. It also contributes about 72 per cent of livestock emissions, according to Environment Canada.
Producers are in need of tools to provide the management information being demanded by the food industry. “Holos is a software program addressing that need. It is both a model and a tool,” says Dr. Roland Krobel, the AAFC scientist in charge of program development. “Holos views the farm as a system and models the current known science of GHGs.”
Two major challenges run through the Holos work. One is the need to keep current and accurate with the science supporting the equations that make the model work. To that end Holos is based on data from the Intergovernmental Panel on Climate Change modified for Canadian conditions when possible.
A second challenge is to make sure it meets producer needs and is user friendly. “It goes beyond the accounting question of what are the farm’s emissions. It answers the question of what will the emissions be if management is modified,” says Krobel.
Holos algorithms have been utilized recently by Dairy Farmers of Canada in a proAction initiative to improve on-farm excellence by Serecon with the Canadian Field Print Initiative, and by Deloitte in a life cycle assessment of the Canadian beef supply chain. The Holos development team is currently looking for partners to turn it into a viable commercial product.
Matthew Wiens of Manitoba Agriculture, Food and Rural Development, and Drs. K. Keriyapperuma and G. Dias of the University of Guelph used Holos to determine soil carbon sequestration in a six-year stand of alfalfa/grass hay. Holos provides the opportunity to choose an appropriate ecodistrict with soil texture and type to model the carbon when fields were switched from annual crops to perennial alfalfa and grass hay.
“We found that kilograms of carbon dioxide (CO2) sequestered per tonne of hay ranged from a little over 74 in the first year to just over 67 in the final year resulting in a total of about 350 kilogram CO2 equivalent/tonne. Although this estimate is subject to uncertainty (+/- 40 per cent), but is still more conservative than recent Manitoba studies which found 400 and 600 kg CO2eq sequestered per tonne of hay,” said Wiens.
“The Holos tool shows farmers where opportunities for carbon sequestration exist, and where GHG emission hot spots are found. GHG emissions are often directly connected to farm inputs, so managing for reduced emissions often means managing for reduced input costs,” said Wiens. For example, Holos calculator results include estimates of GHG emissions from fertilizer manufacture.
“Additional software facilitated our larger life cycle analysis of alfalfa/grass hay production identifying the mowing and baling operations as high energy users, in other words high fuel users. Diesel fuel represented 59 per cent of energy consumption with the actual mowing and baling consuming the most, about 15 per cent each of the total energy consumed. Fertilizer manufacture contributed about 34 per cent of the total energy consumption. Seed production, establishment tillage, seeding and application of fertilizer/herbicide contributed minimally to the total energy use.
Diesel fuel use represented about 59 per cent of energy consumption with total diesel fuel use amounting to 4.3 litres/bale. Nitrous oxide emissions dominated the GHG emissions (70 per cent) during hay production with the majority coming from dry lot manure application.
Potential areas for improved fuel efficiency may be practising optimum tractor maintenance, considering less power-intensive mower types, (e.g. cutter bar mower conditioners), using net wrap instead of twine to reduce wrapping time, using a skid steer to load bales instead of a tractor, collecting bales with a round bale mover, and considering large square balers combined with bale accumulators, said Wiens.
A group of Canadian scientists used Holos to estimate the variability of GHG emission intensities among Canadian cow-calf production systems using actual farm data collected in 2012 from a structured survey of 1,009 farms across Canada. The survey gathered data about various aspects of individual beef operations including feed production, grazing management (warm and cold seasons), seasonal feeding areas, feeding in barns or feedlots, manure handling, storage and application, use of shelterbelts, and factors influencing adoption of new technology. The results have been published in the Canadian Journal of Animal Science (Sheppard et al. 2015).
With the aim of assessing the environmental impacts (GHGs) of beef farms, Drs. A. Alemu, B. Amiro, S. Bittman, D. MacDonald, and K. Ominski are conducting total farm simulations based on the actual farm data obtained from the survey using the Holos model. Alemu and his collaborators selected 295 cow-calf producers who reported sufficient information to estimate GHG intensity. Farms have been categorized based on emission intensity estimates and they are now examining differences in management practices between high- and low-emitting farms. Management practices examined include live weight sold, calving date, calving and weaning weights, replacement rate, and manure management strategies.
“Our study demonstrates a whole-farm analysis, considering the diversity of beef production systems, is required in developing and implementing farm-level GHG mitigation programs and policies,” says Alemu.
Dr. Getahun Legesse and colleagues at the University of Manitoba and Lethbridge Research Centre (AAFC) are assessing the impact of improvements in the efficiency of Canadian beef production over the past 30 years based on the environmental footprint of beef. This project, led by Dr. Tim McAllister (AAFC Lethbridge), is using the Holos model to evaluate greenhouse gas production including methane emissions from cattle and manure, nitrous oxide from manure and soils, and carbon dioxide emissions.
The second phase of the work will identify the important ecosystem services sustained or impacted by beef production and formulate an approach for evaluating them jointly for whole systems.
This whole-systems approach facilitated by the Holos model ensures a management change in one area doesn’t inadvertently cause a negative GHG impact in another area of the farm.