Climate change plan must reward sequestered carbon

When it’s observed that current agricultural practices such as preserving grassland and zero- or minimal-tillage for crops help to sequester carbon — essentially turning farmland land into a carbon sink — the current climate-change policy response is: thank you for your service; now, what have you done for us lately?

Canada’s climate-change plans do not recognize responsible agricultural practices that make an important contribution to carbon sequestration before 2005. Prime Minister Justin Trudeau’s government has adopted the previous Conservative government’s plans to reduce carbon emissions by 30 percent of 2005 emissions by 2030. Carbon sequestering practices in Canadian agriculture had largely been adopted before 2005, so they are not recognized in climate-change programs that provide carbon credits, which can be sold on a carbon market or recognized through tax breaks.

Agricultural policy on carbon sequestration needs to adapt or farmers will quite naturally do what’s best for them financially and convert underused pasture and grassland into cultivated crops, making the land more profitable.

The problem is that practice releases up to 60 percent of the carbon sequestered in the land back into the atmosphere. It takes decades to recover that much carbon in the soil, even if the land is switched back to grassland.

As well, following the law of unintended consequences with government policies, farmers who switch grassland to cultivated crops and then use zero-tillage practices — or even turn it back into grassland — are then eligible for carbon credits, even though there is less carbon sequestered in the soil. As a result, there is more carbon in the atmosphere, leading to a more intensive greenhouse effect.

That grassland loss is happening. It’s thought that Canada has lost two million acres of grassland in a recent 25-year period. Only about 28 million acres of the original 151 million acres in Canada remain as grassland since modern agricultural practices began.

One can understand why governments have been slow to move on this: there is no reliable database on how much carbon has been sequestered in agricultural land. Much depends on the soil. Moist soil sequesters more carbon than arid soil. So painstaking research is needed to establish accurate data.

And a lot of money is at stake.

When Alberta adopted its climate-change strategy, for example, it was thought that the $15 per tonne cost of carbon for the estimated 140 million tonnes sequestered was worth about $8 billion. Alberta’s carbon tax is now $30 per tonne.

And when the federal government structure kicks in at $50 per tonne, there would be lot of money tied up in carbon that would require billions in carbon credits.

But that won’t happen without accurate data.

There are also other benefits to consider: studies suggest that grazed pastureland creates more diversity and stronger vegetation, which is better at retaining carbon and another nasty greenhouse gas — methane — than native grassland. Recognizing this with carbon credits would entice farmers to retain pastureland because grazing is currently the only revenue stream for that land. Switching to cultivated crops would be less enticing.

Worldwide, some 50 percent of organic carbon is tied up in soils. It’s thought that up to 50 percent of carbon is being lost into the atmosphere due to land conversion.

There needs to be leadership on this issue. Canadian carbon plans must assume that leadership by recognizing sequestered carbon on agricultural lands in climate-change programs.

Karen Briere, Bruce Dyck, Barb Glen, Brian MacLeod and Michael Raine collaborate in the writing of Western Producer editorials.


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