Climate Change

Farming for greenhouse gas mitigation

Shifting to a more sustainable system of agriculture

We need to shift to a more sustainable system of agriculture based on livestock and perennial plants said Dr. E. Ann Clark. She has worked with grass and grazing systems for 40 years  as an academic and now a custom grazer for beef cattle. She spoke at the Cap and Trade workshop put on by Hastings Stewardship, as part of the Local Wood Initiative, in Campbellford on March 28.

One can look at greenhouse gas (GHG) mitigation as a service that both farmers and foresters can provide. I am not going to talk about foresters. What I say pertains to both farmers and foresters. The service that farmers are being asked to supply to society as a whole is  GHG mitigation. They are no longer being asked just to provide or produce food, feed, and fibre but also to sequester carbon. What is the link between GHGs and agriculture?  The amount of carbon in the soil underground is greater that the total amount of carbon in the air and living plants above ground parts of plants globally. The amount of carbon is more than the sum you can see above ground, and it is all in managed forests and agriculture. Obviously, agriculture and forestry can be a really useful tool to pull carbon out of the sky and put it in the soil.  You should think this could be a win-win situation because farmers strive and benefit from storing carbon in the soil regardless of GHG mitigation. There are very good reasons for services from organic matter in the soil. Society saying do to farmers continue to do what you do and also store carbon 
There are three different GHGs to consider. Carbon dioxide, nitrous oxide, and methane. The goal to get carbon into the soil faster than it was before. It is about trying to do something you weren't doing before and slowing down the rate of decomposition to increase soil organic matter.  Carbon is 58 per cent or organic matter. Here is the kicker. It is OK to store more carbon at the expense of creating more of these other GHGs, but what you want is a net reduction in GHGs in the atmosphere. If you have to apply nitrogen to increase yield of your cash crop and you are releasing nitrous oxide even if you are storing more carbon in the soil you are not going in the right direction. One molecule of nitrous oxide is equivalent to one molecule of carbon dioxide regarding the impact in the atmosphere.
Of the total GHG emissions in Canada: three-quarters come from the energy sector, the industrial sector is second, and agriculture produces only eight per cent.  Fifty-six metric tonnes of carbon dioxide are the next net emissions from Canadian agriculture. This amount needs to be topped up with an additional 19.4 metric tonnes of carbon dioxide on the farm fuel, and manufacture of machinery and fertilizer,  Fifty-five per cent of emissions relate to livestock farming, because of the methane produced from fermentation in the rumen and manure.
What is the logistics of reducing emissions and increasing carbon sequestration?
Soil sustainability and water management are important and are linked to increasing soil organic matter. It is not just carbon sequestration that is a benefit.
 Agriculture is both a source and a sink for carbon.  A lot of carbon in the atmosphere used to be in the soil and has been released because of agricultural practices. Agriculture can be a source of carbon and a sink for carbon.
 One can argue if we are only eight per cent of emissions one can get a bigger bang for its buck if we spend money on something else. That is a reasonable argument, except there are so many other benefits that come from storing carbon in the soil.
The notion of society asking agriculture to change it isn't the first time this has happened. Society has always informed farmers.
 Carbon mitigation is the latest in a series of directives farming is receiving from society. When society tells farmers to do things they don’t always ask them to do things for free. They do pay. The USDA pays the farmers to do things that conserve water.  In the EU  they have green payments to avoid externalities. It is cheaper to get farmers not to pollute the water than to pay for cleaning up the water.
 There are lots of precedents of society paying farmers when they are asking them to absorb new tasks. It is not unreasonable that this could apply to GHG mitigation.
"Design is the first sign of intention."
If you go to Lethbridge, you see a  million cattle on feed lots. They are planning to ship them somewhere. Design in reflective of the intention.  So what is the intention of paying in agriculture. I am going to suggest to you that this started in the  1800s.  In the 1800s we were colonies, and the role of colonies is to feed the mother country, which ever mother country it is. What you do is ship stuff back to the mother country and what we did with wheat and other products.  We are still shipping it, and it is just that we have changed the recipient. We don't ship to a country we ship to a corporation Cargill, ADM or Greenfield. What we have is bulk, homogeneous,  export-orientated agriculture.
 We have large tracts of land with very few crops that industry wants and with fewer and fewer farmers. The crops are managed and bred for homogeneity with a narrow genetic base specifically to facilitate export-orientated agriculture. I wanted to set the stage this is what we started. This is the design of agriculture today, within which we are being asked to sequester carbon to mitigate GHGs. Can this new task, this new design priority, can it be accommodated within this pre-existing design of export-orientated agriculture.
What are we actually growing in Ontario?  There are essentially three crops, winter wheat, corn and soybeans,  and some small grains, barley, oats, rye and mixed grains. Fruits and vegetables are grown on only two per cent of the arable land. Two per cent is the same number in Canada as a whole and US. Only a remarkable small part of the land is used for growing directly consumable stuff. Also, it is extraordinary how little there is of pasture and improved pastures  37 per cent. 
The Export oriented paradigm.  59 per cent of soybeans 75  per cent of corn and 33 per cent of wheat. Soybeans both feed and food grade.  Food grade all leaves the province and some of the feed grade stays here and is crushed into oil. Everything we are growing is largely livestock feed, processing for industrial ethanol or for export. There is very little grown that we eat.
 Export-orientated agriculture is not designed for greenhouse gas mitigation or sustainability. Agriculture was never designed to be sustainable. It was designed to ship grain to the mother country. If it were sustainable, it would be a co-incidence of miraculous proportions. Ontario and Quebec are losing soil carbon. The Prairies are not gaining soil carbon, but have stable amounts. The west of Canada has many more perennial grasslands and pasture. 
What are the options? We keep messing around doing stuff trying to make it sustainable  But it was never meant to be sustainable.  We just moved on to the next patch of land, we never worry about being here in 100 years from now.  Now we are very worried, but it is a little late.
 The question is can we do GHG mitigation and be sustainable within this export-oriented paradigm. How well have we done in sequestering carbon and reducing GHG in Canada? There is a new document out which one can't download, but one can order it. It is about the current status of soil organic carbon (SOC) and GHG emissions in Canada. The first point is agriculture in Canada is polarized. The  Prairies have five times as much cropland as Ontario and Quebec.
The Prairies have 29 million hectares of farmland and Ontario, and Quebec has 5.6 million hectares. The Prairies have five times as much cropland as we do, ten times as much sown pasture and 17 times as much native pasture.  There are a lot more perennial grown cover in the west. The Prairies produce 75 per cent of the beef in Canada and Ontario and Quebec 75 per cent of the dairy. The Prairies produce 90 per cent of wheat whereas Ontario and Quebec produce 90-95 per cent of corn and soy and 60 per cent of pork and poultry. In Ontario and Quebec, we are minor players regarding beef and canola.
Ontario and Quebec are not doing well regarding maintaining soil organic matter. There is a big difference between the east and the west. They are not gaining soil organic matter in the Prairies,  at best they are staying even In the west there is a larger proportion in perennial sod. Nowhere in Canada are we increasing soil organic carbon, no matter how we are managing it. In central Ontario losing organic matter.
What about GHG emissions?. There is less emission in the Prairies. Nitrogen fertilizers are used on the corn soy and canola grown in Ontario and Quebec. There does not take much to release of nitrous oxide, which is 300 times as bad as carbon dioxide in the atmosphere and thus nullify the impact of sequestering carbon.
There is scant evidence that export-orientated agriculture can sequester carbon or mitigate GHSGs. The Prairies are doing a much better job  in that they are at least sustaining the soil carbon
What can we learn from why the Prairies and Ontario are so different that can help us drive the direction of agriculture in the future. The big difference is no-till in the Prairies and the loss of perennials in East and the use of high nitrogen on corn in the East.
 No-till has been adopted in the Prairies with between 60- 78 per cent farmers using it. It is a lot less in Ontario and very little in Quebec. We do have no-till in Ontario but a lot less of it. The lack of no-till is due to economics,  and soil type. There are heavier soils in Ontario and Quebec. No-till doesn't work on wet soils and can cause nitrous oxide emissions, and pathogens build up.
There are lots of argument for no-till regarding the soil surface, but the bigger question is the impact is the what happens when annuals replace perennials. For centuries in Canada, everything was perennial. There are only a few places where it is so dry that only native annuals can survive. 
 What if the design drivers were to lower GHG emission and improve soil sustainability rather than crop yield. Who will pay for it?
Do we just make it less bad or should we bit the bullet and make it good? What would agriculture look like if designed not just food, feed and fibre?
Soil sustainability would need a perennial based landscape with grass being used for grazers. Don't sell hay as this reduces the amount of plant material that can go back into the soil on the farm.
It is important to remember that “what can be made by policy can be unmade by policy.” 
We are facing a number of issues such as an annual water deficit. The  Prairies are a very fragile environment.  We need about think to the future. There is an impending water crisis in the prairies.   Beef cattle, dairy cattle, sheep, and pigs can all eat grass.
The best way to increase soil organic matter and to sequester carbon is by minimizing soil disturbance, covering the soil at all times, stimulating microbes by crop rotation and reducing tillage. No-till is not enough; one needs to bring perennials into the rotation.
Grazing and livestock need to be brought in if we are to achieve a reduction in GHG emissions and if we want to sustain soils.
The manufacture of nitrogen fertilizers releases GHGs and uses fossil fuels. Nitrogen applications have doubled over the 30 years between 1981 and 2011. Nitrogen can over stimulates the microbes in the soil, which promotes the breakdown of SOM and the loss of carbon. Heavy reliance on nitrogen for export crops is clearly at variance with goals of GHG abatement. Nitrogen stimulates yield and also the breakdown of SOM and the release of GHG.
Zero till is a poor fit in eastern Ontario with our soils and moisture. At present, cropping and livestock production are polarized. We need to bring perennials and animals back into the system. We need precision farming with a low release of nitrogen and the use of cover crops. We also need new crops designed with improved nitrogen efficiency.
We need to consider policy as well as biology. We need grass and grass needs grazers. We need to redesign agriculture and incorporate livestock as livestock are the bridge to environmental sustainability. You can't go with annual crops year after year. There needs to be perennials and grazing.  We need champions because it is the right thing to do.
As well as changing agriculture there is potential for improving forests and getting funding for healthy forests.
Read her full transcript.


April 7, 2017 - 19:00