Do Cows Emit a Lot of Greenhouse Gases?

Once upon a time in the USA there used to be a vast area of prairie (pasture) called the Great Plains. This story can be replicated on any of the world’s grasslands. This vast grassland was a giant ‘carbon sink’ with deep soils of up to 15% organic matter and was a rich habitat for thousands of different species of flora and fauna. Even through severe droughts the plains supported somewhere in the region of 110 million wild ruminants. 50-70 million of those were the giant one tonne bison – the equivalent to about 2 small beef steers. We now, in the USA, have roughly the same number of domestic ruminants (sheep, cows, and goats).

Wild animals burp and fart too you know! So how come pre-industrialization these ‘evil’ ruminant beasts didn’t wreck our climate?

Healthy soils contain soil microbes called methanotrophs that reduce atmospheric methane. So the grassland on which the cattle are grazing can absorb a large amount of the methane they produce. The highest methane oxidation rate recorded in soil to date has been 13.7 mg/m2/day (Dunfield 2007) which, over one hectare, equates to the absorption of the methane produced by approximately 100 head of cattle.

‘Methane sinks’ bank up to 15% of the earth’s methane. Converting pasture into arable production reduces the soil’s capacity to bank methane and releases carbon into the atmosphere. Fertilizing and arable cropping reduce the soil’s methane oxidation capacity by 6 to 8 times compared to the undisturbed soils of pasture. The use of fertilizers makes it even worse, reducing the soil’s ability to take up methane even further.

So to convert pasture to arable land in a ‘quick fix’ to try and grow more plant-based foods considerably accelerates the climate change situation.

And anyway let’s put enteric methane (cow burping methane) into context. According to the 2014 UN Climate Change Convention held in December in Lima, Peru, the analysis of GHG’s (greenhouse gases) when converting other gases to CO2 equivalents found that in the US and EU enteric fermentation accounted for 2.17% of GHG emissions. (26.79% of agriculture emissions with all agricultural emissions in total being 8% of total GHG emissions).

Have you looked into the methane output of rice paddies recently?

The largest increases in methane levels occurred in the 1960’s when we started using nearly ten times the natural gas.8 And contrary to common belief, cattle numbers have not increased. Even in the US they are the same as they were in the 1950’s (Source USDA), while globally they have been static since the 1970’s (Beef 2 Live). Our meat consumption has increased because we eat more intensively farmed poultry and farmed fish, but we don’t NEED to eat this much meat.

Eating beef can actually be a very sustainable option. In many cases pasture reared beef actually shows a carbon-equivalent net gain when carbon sequestration is taken into account.

So why are we focusing all of the attention onto farting cows instead of looking at how we can cut out the 73% of agricultural emissions that are created by farming that uses grains and fertilizers? Because there are a lot of people making a lot of money from their finger in this enormous agri-pie! They want you to believe that the answer is bigger more efficient farms and GMO!

The above is excerpted from an article on Primal Meats. Read the rest of the article here: The superfood that could save the world.

References from the article:
  • Hristov, A. (2011). Wild Ruminants Burp Methane, too. In PennState Extension. Retrieved from http://extension.psu.edu/animals/dairy/news/2011/wild-ruminants-burp-methane-too
  • Jones, C (2014). Ruminants and Methane. In The Natural Farmer, Summer 2014. Retrieved from http://www.nofamass.org/sites/default/files/2014_Summer_TNF_Jones_on_Ruminants_and_Methane.pdf
  • Jones, C. (2010). Soil carbon – can it save agriculture’s bacon?. In www.amazingcarbon.com. Retrieved from http://www.amazingcarbon.com/PDF/JONES-SoilCarbon&Agriculture%2818May10%29.pdf
  • Singh, J.S. (2011). Methanotrophs: the potential biological sink to mitigate the global methane load. In Scientific Correspondence, Current Science, VoL. 100, no. 1, 10 January 2011. Retrieved from http://www.researchgate.net/publication/259079734_Methanotrophs_the_potential_biological_sink_to_mitigate_the_global_methane_load
  • Singh, J., Shashank, T., Singh, D. P. (2015). Methanotrophs and CH4 sink: Effect of human activity and ecological perturbations. In Climate Change and Environmental Sustainability (April 2015) 3(1): 35-50. Retrieved from http://www.researchgate.net/publication/274573824_Methanotrophs_and_CH4_sink_Effect_of_human_activity_and_ecological_perturbations
  • Kremer, R.J., Means, N.E. (2009). Glyphosate and glyphosate-resistant crop interactions with rhizosphere microorganisms. In European Journal of Agronomy Europ. J. Agronomy 31 (2009) 153–16. Retrieved from http://naldc.nal.usda.gov/download/35795/PDF
  • (Anonymous). (2014.) Summary of GHG Emissions for United States of America. In United Nations: Climate Change Secretariat. Retrieved from https://unfccc.int/files/ghg_emissions_data/application/pdf/usa_ghg_profile.pdf
  • (Anonymous). (2013). Grass-fed beef is best. In National Trust. Retrieved from http://www.nationaltrust.org.uk/article-1356398465642/
  • Allan Savory: How to green the world’s deserts and reverse climate change [Video]. (n.d.). Retrieved from https://youtu.be/vpTHi7O66pI

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