Storing carbon in farmland isn’t quite as straightforward as it might seem. Paying farmers properly for doing it is even more complex.
That’s what governments appear to believe but before any payment plan is formed, we need agreed ground rules about western Canadian soil.
Depending on who is asked, 15 to 20 percent of all earth-stored carbon, the terrestrial-contained stuff, is in farmland or pastures. Well-managed pastures get a lot of credit for carbon storage. Land used for crop production gets pretty good marks too if tillage is kept to a minimum. Most players agree on those two points.
Then the views of governments, some scientists, non-governmental organizations and farmers diverge.
Who owns the sequestered carbon in the field? It seems obvious it belongs to the farmers who put it there. Carbon storage isn’t unlike grain storage. Farmers produce it. The more they invest in their crops’ nutrients and the technology and techniques to grow food, the more successful those crops are and the more root mass they create.
Longer-term rotational strategies and cover crops, where moisture is sufficient, can enhance the process. It results in improved levels of soil organic matter, measured as soil organic carbon, and that means more carbon stored under boot.
While it isn’t quite that simple, it is nearly so.
Some credible American researchers suggest there are limits to the amount of carbon a field can reasonably store. According to the American National Academy of Sciences, another three billion tonnes of carbon could be stored in soil if all farmed land avoided cultivation and was well cropped. After that, the academy believes carbon sink supplies are limited. But demand for sequestration continues to expand.
Research has shown that prairie farmers have, between 1985 and 2010, reduced greenhouse gas emissions and have sequestered carbon for the Canadian public benefit to the tune of more than $10 billion, if carbon is valued at $50 per tonne.
Farmers didn’t do this to bank the carbon. They did it to survive economically. In that 25-year span it is estimated producers improved their farming returns through reduced tillage and continuous cropping to the tune of $23.4 billion.
Farmers invested heavily in new technology, crop development and inputs to accommodate this transition. Prairie carbon storage has been a slowly building bank account since the early 1990s.
Producers who haven’t been storing carbon this way will expect government and market incentives to encourage the change and underwrite their investments in reduced tillage and cover cropping. Why shouldn’t they? After all, a price is being put on it.
Governments would like to set a fixed date, a recent date, that declares the level of carbon stored as zero. Any improvements would then have a price attached to them.
But this tells producers who have been improving their land and filling their carbon banks for years that they won’t be compensated for their efforts and investments. The state will effectively confiscate the carbon. Will those who have not saved carbon be rewarded for changing their ways? It appears so.
Setting a day-one carbon date in 1995 would be more appropriate for Western Canada. Otherwise, it could encourage massive tillage so that a subsequent halt to cultivation would garner dividends. If farmers are paid to fill their soil “bins” with carbon, at some point they might have to empty them so they can harvest another crop. And that will be detrimental to the environment and the soil.
Paying farmers to sequester carbon is a good idea but a start date for sequestration calculations must be considered carefully.
Karen Briere, Bruce Dyck, Barb Glen and Mike Raine collaborate in the writing of Western Producer editorials.
