MORE EFFICIENT CANADIAN BEEF PRODUCTION EQUALS LOWER WATER USE INTENSITY
Canadian beef producers have reduced water use by 17% per unit of beef over the past three decades.
This simple statement reflects two years of rigorous, detailed study involving an entire team of well-respected Canadian modellers and beef production scientists from the University of Manitoba and Agriculture and Agri-Food Canada Lethbridge Research and Development Centre. Two years spent combing countless reference sources and cross-Canada datasets on hundreds of model parameters to first, critically evaluate existing water footprint methodologies, and second, build a Canada-specific water use intensity calculator to arrive at this single number.
This water use intensity calculation is part of a larger project to define the environmental footprint of Canadian beef production and the change in this footprint over a thirty-year period. In earlier research the team showed a 15% reduction in greenhouse gas emissions and a 20% reduction in ammonia emissions per unit of beef over the same period, between 1981 and 2011.
Getahun Legesse from the University of Manitoba led the development of the beef production component of the water use model, as well as the review of water assessment methodologies that preceded the water footprint calculation effort.
A recent scientific review paper published in the Journal of Animal Science by a team of international researchers that included Getahun Legesse, Kim Ominski and Emma McGeough with the National Centre for Livestock and the Environment at the University of Manitoba and Tim McAllister, Karen Beauchemin, Roland Kroebel and Marcos Cordeiro of AAFC-Lethbridge shows that the size of the beef footprint really depends on how it was calculated.
Why 1981 to 2011?
The thirty-year period of 1981 to 2011 was selected for variety of reasons. According to Legesse, the Canadian beef cattle inventory has not seen a notable change since the 1980’s. Growth in cattle inventory during 1981-2011 was only 1%, compared to 60% in the previous 30-year period. Therefore, any changes observed during this period would likely not be as a result of changes in cattle numbers. Access to sufficient quality data was also an important factor in selecting these start and end periods. Both 1981 and 2011 were Statistics Canada Census of Agriculture years for crops and livestock, plus other published Canadian studies have used 1981 as a historical reference year. Thirty years has also been deemed an adequate time period to capture potential differences, having been used as the basis for studies in both the U.S and Australia.
What did they do?
To determine the appropriate approach for calculating water use for Canada’s beef herd, they first conducted an extensive review of the benefits and drawbacks of the various water footprint assessment methodologies published in scientific literature. “Water models are still evolving, so rather than using a single tool, we used a mix of methodologies based on the availability of data and the strength of the individual models,” says Legesse. “We decided to focus on water use intensity, defined as the amount of water used to produce a kilogram of beef.”
Following animals throughout the entire production cycle from cradle to farm gate, they accounted for temporal and regional differences in cattle categories, feed types and management systems, average daily gains and carcass weights. Altogether they accounted for close to 50 different feeding scenarios for each time period. Water input sources included precipitation, surface water and ground water.
In addition to the agriculture census data, they drew from Canadian Beef Grading Agency carcass data, obtained water use coefficients from FAO (Food and Agriculture Organization of the United Nations), consulted provincial bodies for irrigation water use, used national surveys of beef operations, and consulted published scientific sources.
Marcos Cordeiro with AAFC-Lethbridge led the development of the crop production component, using different models to capture water demand and to determine water use for producing crops and pastures used as cattle feed. Cordeiro ran crop water simulations using evapotranspiration data from 679 meteorological stations distributed across Canada.
What did they find?
“Overall we found that total water use per kilogram of beef was 17% less in 2011 than it was 1981,” says Legesse. When precipitation was included in the analysis, 99% of the water use in cattle production was related to feed production. When precipitation was left out, drinking water accounted for 22% of water use.
Why did water use intensity decrease?
A number of reasons lie behind the reduced water footprint. These include the prominent gains in cattle production efficiency over the past three decades, resulting in a significant increase in the amount of beef produced per animal. Reproductive efficiency, average daily gains and body weights have increased between 15 and 45%. Over the same period there have also been significant improvements in yields of barley and corn, the main feed crops.
Why care about water use?
“Generally Canada is referred to as a water rich nation due to its freshwater resources, yet more than half of this water is retained in lakes, underground aquifers, and glaciers. The distribution and availability of water also vary considerably across the nation,” notes Legesse. “Just as in other regions of the world, water in Canada can be depleted both in terms of quantity and quality.”
In light of increasing pressure on water resources associated with increased food demand, Legesse believes that taking into consideration all parameters of water use is very important for agriculture as a whole, and the beef industry in particular. “Hopefully in the future we will build on what we have already done to look at specific regional impacts of water use and the implication of beef production on water quality. Having this volumetric data that this study provides was an important step in that direction.”
Research team: University of Manitoba - Getahun Legesse, Kim Ominski and Emma McGeough. AAFC-Lethbridge - Tim McAllister (overall project lead), Marcos Cordeiro, Karen Beauchemin, Roland Kroebel and Sarah Pogue
Financial support for this project provided by the Beef Cattle Research Council and Agriculture and Agri-Food Canada through the Beef Cluster Project.
Legesse, G., M.R.C. Cordeiro, K.H. Ominski, K.A. Beauchemin, R. Kroebel, E.J. McGeough, S. Pogue, T.A. McAllister. 2017.Water use intensity of Canadian beef production in 1981 as compared to 2011. Science of The Total Environment. 619–620: 1030-1039. doi.org/10.1016/j.scitotenv.2017.11.194
Legesse, G., K.H. Ominski, K.A. Beauchemin, S. Pfister, M. Martel, E. McGeough, A.Y. Hoekstra, R. Kroebel, M.R.C. Cordeiro and T. McAllister. 2017. Quantifying water use in ruminant production. J. Anim. Sci. 95:2001–2018 doi:10.2527/jas2017.1439
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We examined changes in the water use intensity of Canadian beef production over a 30-year period.
Water use intensity declined by 17% despite an increase in total water use.
Feed production accounted for 99% of water use in beef production
More improvement is possible by increasing feed production and feed efficiency
Photo: B. Fisher