Software developed by Agriculture Canada calculates the value of carbon management under various production systems
Shathi Akhter wants to add hard numbers to an issue that has often relied on altruism.
“We all know wetlands are good, shelterbelts are good, but how good are they, where’s the dollar value?”
Akhter is an agroecosystems scientist with Agriculture Canada at its Indian Head Research Farm near Indian Head, Sask. She specializes in what is often termed unproductive land: wetlands, sloughs, shelterbelts, and road allowances.
She said there are many benefits of preserving and even expanding such areas. Shelterbelts have a yield cost in bordering areas, where the crop competes with the trees, but a yield gain further out from better moisture from captured winter snow and reduced evaporation from wind. The net result: better net yields on fields with shelterbelts.
Likewise, Akhter said sloughs and wetlands act as “buckets” to capture spring moisture, slowly giving up their contents over the growing season to benefit crops. Their willows can be harvested too, for bioenergy or biochar. They also act as habitat for beneficial wildlife, such as insects that pollinate crops and birds and amphibians that help to control pests.
Without the buckets, local crops are prone to drought, and a valuable resource is lost downstream, where it becomes a problem.
“So we can’t grow crops here, while our friends down in Manitoba are all flooded,” Akhter said.
Akhter concedes these arguments aren’t always convincing to a farmer who must deal with a field broken up by numerous sloughs and bluffs, something made more challenging by the growing size of farm equipment over the past decades.
One argument that does resonate is dollars. Is that shelterbelt, that wetland or slough, worth more as-is, or better converted to cropland? Akhter and her colleagues wondered if climate change, and government policies around carbon, might make “unproductive” land productive, albeit in a different way.
Calculating the value of carbon management under various production systems is the purpose of the Holos computer modelling software program developed by Agriculture Canada. Free to producers, Holos “estimates greenhouse gas emissions based on information entered for individual farms.” This allows producers to run different scenarios to guide their management decisions.
Holos uses data from Akhter and other researchers across Canada as its foundation. It is regularly updated as new information comes in. One of the modellers is Agriculture Canada Lethbridge researcher Roland Kröbel, who has used his own work to develop models for beef and forage.
Silvipasture, or bush pasture, is another of Akhter’s research interests. Livestock producers must make decisions whether their land would better suit grazing with more trees and less grass or vice-versa.
It’s an issue put forward by Pincher Creek rancher Malcolm Main in a recent issue of The Western Producer. He argued producers should expect credit for choosing practices — in this case, more trees — that sequester more carbon.
Akhter points to the federal government’s plan to plant two billion trees to help sequester carbon. These trees won’t be planted in the North, which is already covered by boreal forest, but in the south, on farmland. This means producers must see the payback for planting trees.
This can be through direct government incentives, but Akhter advocates making the trees and shrubs such as walnut and hazelnut pay for themselves. For example, farmers could plant seabuckthorn or buffalo berry, both of which fix nitrogen, on marginal, degraded or saline lands. While such trees take time to produce a marketable crop, in the meantime they capture moisture, reduce salinity, and increase microbial activity.
“In 10 or 15 years, you’ll have different land than what you started with,” she said.
The strength of trees, willows, or any plant is that they sequester carbon for free as they grow. For instance carbon accounts for about half the dry weight of wood, but it’s released as it decays. Titan Green Energy Projects in Craik, Sask., permanently captures it and turns it into value-added products.
Titan produces biochar, which is almost pure carbon created from any biomass, be it oat hulls, hemp and flax straw from farmers and food processors or waste wood from construction. The company has also worked with Indian Head researchers on projects to produce biochar from slough willows and cattails harvested from Lake Winnipeg. The company was the first to produce a pelleted biochar, a proof-of-concept product designed for use in air seeders.
Biochar is not new. Jamie Bakos, president at Titan, explained the product was used in the Amazon basin in South America to enhance agriculture. Called terra preta, these soils are easily identified as a dark, even black, layer.
“We can physically see charcoal has lasted 1,500 years in soils and those soils are some of the most productive today,” Bakos said.
While the product is ancient, the Titan process is new. Biochar is produced by heating biomass in an oxygen-free environment at somewhere between 350 C and 1,000 C (the sweet spot seems to be 550C for the best yield). This cooks off any liquids and gases. These include carbon monoxide, methane, and hydrogen, collectively known as synthesis gas or syngas.
“We have the only autothermal process,” Bakos said, explaining Titan uses biofuel to bring the process up to operating temperature, then uses the syngas.
“We don’t need any outside electricity or natural gas or fossil fuel to keep the process going. It’s fully operated by the heat generated by the biomass.”
Bakos said every tonne of biochar produced by Titan is the equivalent of pulling two and a half tonnes of carbon out of the atmosphere.
“It’s a fully carbon-negative process that’s recognized by the Intergovernmental Panel on Climate Change now, as of 2018,” he said. “I don’t think there’s any more cost-effective way to remove carbon from the atmosphere. In fact, it’s profitable to do so.”
Where there is profit, there is incentive. Bakos advocates producers getting their slice of the carbon pie, whether it’s directly from providing biomass to produce biochar and generating carbon credits, or indirectly by using products such as biochar products.
An example is feed supplements that reduce methane and odour from cattle and end up as carbon-rich manure for soil amendments. Another is using biochar to replace peat moss, a non-renewable resource, as a carrier for pulse crop inoculants.
“I think that’s something that needs to be fleshed out a lot more,” Bakos said. “We have a carbon tax and there’s value associated with carbon reduction from the atmosphere, but how does everybody get paid for that?”
He argued that farm practices that sequester carbon are a public good that should be recognized.
“If there’s value associated with those carbon reductions, then those benefits should go to farmers.”