Location: Montreal, QC mostly. Developing in Southern New Brunswick, Canada.
posted 1 year ago
Dear Permies Mega Brain,
I’ve done some googling and some permies.com searching and come out with precious little solid info and so I’m hoping to crowdsource some decent, non anecdotal data from you all as I know you to be an incredibly diverse and intelligent bunch. Excuse me if this thread already exists and I failed at google. Also... moderators : this may be a cider press subject..
**bias alert** my bias is clearly on the side of what I imagine being the traditional permaculture view of this subject : Responsibly raising animals, ruminants in particular has a net benefit and is in fact GHG negative in at least a whole systems context.
For this exercise let’s forget about the myriad ecosystem services grazing animals provides in a whole systems approach.
background/ context :
I have always, since beginning reading on permaculture been very excited about the prospect of carbon capture using permaculture principles including through soil building with ruminants and other animals.
There is however a strong movement on the rise that postulates that ruminants are a key cause of climate change, and removing them from our diets, and thus our agricultural systems could help us meet certain emissions targets.
I’ve disagreed with this position up to now as many of our permaculture thought leaders have asserted or implied the opposite. However, the cows are bad movement is now backed by scientific studies that appear to support the claim. In my revision of some of the key numbers they seem to be poorly contextualized, and not qualifying between industrial CAFO / grain fed animals and 100% or even 40 % grass fed animals. (40% is the requirement to be able to call an animal product ‘grass fed’ I understand.)
What I know/have found :
AFAICT the numbers floating around about total GHG generated by livestock are as follows:
14.5 % of all GHG are generated by livestock (Édit) globally. Unclear if this includes processing, feed production, and direct (aka cow gas). Includes all forms of livestock. Not sure the source of this number but it’s been quoted quite a bit and shows up as a first hit on google.
1.5-2% of all GHG are directly generated by livestock (again... cow gas, again not qualified ). This number is from the EPA and can be found on their website.
** my understanding is that these GHG % are weighted by potency eg. methane greater than carbon, nitrous oxide (from the application of ammonia to crops) greater again..
I don’t refute these numbers but I’m not here to talk about them primarily.
The question :
I’m not finding the hard evidence that backs the claims of our thought leaders that suggests grazing animals sequesters carbon through soil building. How much carbon ? Using which practices ? Peer reviewed ?
I would like to see numbers/ scientific studies from credible on anecdotal sources that specifically refer to the ability of ruminants in particular to sequester carbon through grazing, using best practices and including definitions of these practices.
If that number is clear, then we can compare against the average direct GHG released by a cow (cow gas again) and get an answer that’s better qualified for grazed animals, with respect to the assertions floating around these days about what role these animals may play in causing, or repairing climate damage.
Thanks all !
Companion Planting Guide by World Permaculture Association