I recently tweeted about a Blog Entry from another site that discussed organic food production in the context of Global Warming. If you don't like that term, use Climate Change.
The entry provides a data based position vs. emotional. I am all for that. My signature on personal emails ends with this quote by Roger Brenner (economist), The sum of anecdotes is not data. Here, here Mr. Brenner.
A twitter friend of mine, Joya (@kubileya) read that entry and replied back as follows:
@natejtaylor Of course you like the article. Seems flawed to me. Proper aerobic composting does not produce methane, tmk. Anaerobic does. ??
@natejtaylor Ah, I see. IPCC study cited by Savage looks @ swine&dairy CAFO manure emissions. That, my friend, is *conventional* ag problem
@kubileya why would you say" of course you like the article?" Why do you think I like it?
@natejtaylor B/c you like to be contrary and argumentative. And you like to poke ProFood. :-)
@natejtaylor It bothers me that his data for assessing organic emissions is founded on a study on CAFO manure systems. That aint sustainable
@natejtaylor And it aint true organic- not one ProFood advocate I know wd consider that acceptable, no matter what USDuh regs say
@natejtaylor Seems he's setting up a straw man argument. Do you have data on methane from aerobic v. anaerobic composting?
I place the above interaction (yes I am aware of the redundancy, but just in case non-twitter users read this...wait is there such a thing?..I digress). in this post for 3 reasons:
1.) To say thanks to Joya for taking the time to not only read the blog, but actually provide some feedback. I truly appreciate that. We must continue our interactions.
2.) So the readers will have a little background
3.) To acknowledge Joys'a point about poking Profood. I may be a tad guilty of that. But hey, it gets us talking about agriculture!
Now, as for the IPCC study. I read through it also and it actually breaks out the classes of livestock by region. Almost all regions had grazing with North America having more livestock finished in a feedlot. And certainly CAFO's were included in the study.
What I would like is to open this up to a discussion, specifically around composting and fertilization of cropland.
Let's talk a little bit about composting; I say little because I am a neophyte when it comes to the chemistry and science involved. There are two types of compost as mentioned in the above tweets, aerobic and anaerobic. Each has positives and negatives.
Aerobic:
Aerobic compost creatures gets its name for the Greek word for air, meaning these little creatures need air to carry on their work. While they are busy working, heat is generated. This heat is what kills off the weed seeds and germs in the pile. Since they need air, the compost pile requires a great deal of work to keep the process moving. This means that it is labor intensive. Depending on how quickly the compost is needed will determine how many times you have to turn the pile over, re-wet it, and cover it up again for decomposition to continue. You will know when the compost can be left to mature when after returning the pile little heat is generated. This means the carbon has been converted to CO2 and the nitrogen into nitrates and ammonia. One of the biggest benefits to this type of composting method is that no methane is produced, IF handled "properly". As we all know, this is beneficial to the environment as methane is a GHG.
Anaerobic:
Anaerobic compost creatures do not like air. Once you wet the pile and cover it, you just let it sit. At first the aerobic organisms will go to town; however, once they use all the available air, they die and the anaerobic organisms are formed and begin their work. This type is less labor intensive. Anaerobic composting takes a bit longer to "mature" before it can be used as a fertilizer so this usually requires more space as the piles need to sit longer. This type of compost will usually have an overabundance of Nitrogen, thus causing that awesome smell we all know and love. A big drawback to this type of composting is the methane gas that is created. Consequently, this impacts the climate negatively as methane is a GHG.
As the author of the blog post stated, methane gas was created with all composting methods. The data he provided was based on composting with 8 "turns" in a 99 day composting period. Does this mean that "proper" aerobic composting procedures were not followed? If so, what should be done?
Joya made a good point in terms of CAFO's. Not all are sustainable when the practices are BAD. My counterparts in the #ag industry will not stand for such practices. It gives us all a bad rap and further works to alienate consumers and producers.
Crop production needs fertilizer, and the data shows that compost alone does not provide the amount needed, thus crop rotation with Legumes or other Nitrogen producing crops. Do we forgo any synthetic fertilizer or just create more compost? Can the issue be solved with better crop rotation? How about a bio-dynamic system?
So where does this leave us? I don't rightly know actually. If #organic food production, as one of my other twitter friends stated, "requires allot of shit", where are we going to get it from? Fish? Cows? Chickens? Do we have enough land/pasture to "house" all these animals to create enough manure? How about the infrastructure? And is it truly sustainable in the context of climate change to transport all this compost? Maybe we need more commercial composting businesses opening up and creating a regional based supply chain? I would be in favor of that.
In the mean time, "conventional" agriculture is going to continue to progress. Science, technology, and advanced communications are going to leveraged to the hilt to further reduce the dependence and usage of fossil fuel based inputs. If you think agriculture has changed over the last 20 years, you ain't seen nothing yet!
I open the floor to ideas, points/counterpoints about composting, anything really. There is no 1 right answer. So let me know and stay tuned for a deeper dive into manure handling and management.
Although I still take issue with Mr. Savage's article and the study it is based on, I'll dig into the composting bit a little. Handled properly, an aerobic composting process will not produce methane since, as you have pointed out, the microorganisms that produce the gas can not survive or thrive in an oxygenated environment. Keeping the pile in proper balance requires an excellent understanding of the biology behind the process and careful monitoring of moisture, a balance of carboniferous materials and proper aeration. Methane production can only occur in an otherwise aerobically handled compost pile if it is not properly managed. It is obvious that the Canadian company had just such a problem.
Which brings up a good point. As in most things, there are good practices and bad. Certainly, methane production from improperly composted materials should be addressed when it occurs and composting should be treated as the biological science that it is, not as some haphazard voodoo mumbo-jumbo. But, it is falacy to apply the practices of one company in Canada to all composting operations and assume that compost is going to drive us deeper into climate change (what is it y'all always say about a 'broad brush?'). We should seek to make sure that all composting operations are using the best possible practices, but we certainly should not abandon it or abandon organic agriculture as Mr. Savage seems to suggest.
To put compost methane emissions into perspective, here's the EPA's take on the largest anthropomorphic producers http://www.epa.gov/methane/sources.html
You'll notice that composting is quite far down the list. Manure management is pretty high up there, and this is another issue I took with Mr. Savage's article-- he included manure storage before composting as part of his calculation of methane emissions from organic agriculture. The lagoons and where this CAFO manure is stored is *not* a problem associated with organic agriculture. It is a direct result of the industrialization of animal production and would simply not exist or proponents of organic agriculture had their way.