New research data by Jude L. Capper, expert on the environmental impact of beef at Washington State University, comes to the conclusion that improvements in U.S. beef industry productivity have reduced the carbon footprint of beef production.
The study titled “Comparing the environmental impact of the US beef industry in 1977 to 2007” at first analyses the historical situation. Historical livestock production is commonly perceived to be inherently more environmentally sustainable than modern agricultural practices. This study modeled the environmental impact of the 1977 US beef industry, which produced 10.6 billion kg beef from 38.7 million head slaughtered, compared with that of 2007 (11.9 billion kg beef produced from 33.7 million head).
The deterministic environmental impact model integrated resource inputs and waste outputs from animal nutrition and metabolism, herd population dynamics and cropping parameters using a life cycle assessment approach. Rations were formulated according to NRC for growing animals (steers, heifers) at breed-appropriate bodyweights and growth rates; and for the supporting population (cows, bulls, herd replacements). System boundaries extended from the cow-calf operation to arrival at the slaughter plant, thus all operations and transport within these limits were included. Resource inputs included feedstuffs, water, land, fertilizers and fossil fuels. Waste outputs included manure and greenhouse gas emissions. The total animal population required to produce one billion kg of beef in 2007 was reduced by 27% compared with 1977.
The decrease in population size conferred reductions in total feed energy, feedstuffs and land use of 10%, 17% and 27% respectively. Water use per billion kg beef was reduced by 15% between 1977 and 2007. Compared with the 1977 beef industry, fossil fuel energy for beef production was reduced by 11% per unit in 2007. Methane and nitrous oxide emissions per billion kg beef produced in 2007 were reduced by 17% and 13% respectively.
The total carbon footprint (expressed as CO2-equivalents per billion kg beef) was therefore reduced by 14% in 2007 compared with 1977. This analysis clearly demonstrates that improvements in US beef industry productivity conferred by advances in slaughter weight, growth rate, nutrition and management have considerably reduced the environmental impact of modern beef production, thus improving the sustainability of livestock production.
Source: Washington State University