The federal government’s targets for greenhouse gas emissions currently include a 30 per cent reduction in nitrous oxide emissions by 2030, which the government called both “ambitious, and achievable.”
However, Canadian farmers and agriculture organizations across the country have doubts about this target. Western Canada already ranks fairly high on the global nitrogen use efficiency scale, according to Rob Saik, founder and CEO of AGvisorPRO, but there are always reasons to keep improving. Saik and other industry leaders all agree there are already some extensively researched best practices that farmers can introduce on their operation, but more needs to change for adoption incentives and cost sharing.
Basic Agronomics
For Saik, the first step in adopting efficiency practices are farmers knowing the basic agronomics of their field. While there are a lot of blanket approaches or recommendations, each region – even every field – has its own soil makeup, nutrient levels, hydrodynamic needs, etc. Moving from one field to another could mean drastic changes in what practices would be the most effective.
The majority of Western Canada soils have not been soil tested, but if this became common practice, individual farmers would have vast amounts of information on what is in their field, from the level of organic matter to nutrients; including nitrogen and other essential nutrients like phosphorus, potassium and sulphur that are also vital for plant growth. This can be used to formulate an efficiency plan for the growing season with agronomic recommendations also being used to demonstrate and measure emission reductions and efficiencies, says Saik.
Saik also notes that volatilization, nitrification and leaching cause the biggest losses of nitrogen, one through evaporation and the other two through water movement. These losses can be significant.
“They can be anywhere from five to 15 per cent, and in high pH soil conditions, that volatilization can be as high as 30 per cent,” says Saik. “So, think about at 100 pounds of nitrogen per acre, and losing 10 per cent of that nitrogen to the atmosphere as free ammonia to the volatilization.”
Knowing the agronomics of their field can help farmers take action to reduce these losses, he notes, but more incentive policies could be put in place to help farmers. “Can we get some sort of an incentive for adopting technologies that would reduce volatilization and leaching, thus resulting in a reduction of nitrous oxide emissions?”
4R Stewardship
4R nutrient stewardship – right source, right rate, right time, right place – has become a mainstream practice over the last few years, and research institutions have been working on it for the last decade, according to Mario Tenuta, senior industrial research chair of 4R nutrient stewardship at the University of Manitoba. The program itself is done in partnership with Natural Sciences and Engineering Research Council of Canada, Western Grain Research Foundation and Fertilizer Canada with the sole purpose of finding ways of reducing nitrous oxide emissions in Canadian farming practice through extensive field research.
Farmers have always practiced 4R stewardship in some form, Tenuta says, but now they are working on tracking the full extent of these practices and the difference they are making in nitrous oxide emissions reduction.
Through their research, they are seeing more reductions when fertilizer is applied at the very end of October or beginning of November, even early spring. However, through split applications of fertilizer applications being included in the growing season, Tenuta says they are finding upwards of a 60 per cent reduction of nitrous oxide emissions when, for example, application is done to knee-high grain corn in Manitoba.
“We’re primarily looking at more early growing season applications in the nitrogen rather than later in the season,” he says, “which is a bit riskier, especially as you get more and more arid to the west and southwest.”
Wetter conditions make for higher emission rates through those nitrification and leaching processes, so Tenuta admits this is a balancing act for finding the right time.
Nitrification Inhibitor
The simplest practice that Tom Bruulsema, chief scientist with Plant Nutrition Canada, notes for farmers to adopt is a nitrification inhibitor. There are a number of products available that will slow down nitrification and therefore reduce emissions from anywhere between 20-50 per cent. However, there are some difficulties in measuring the absolute effect since reduction levels are dependent on a few factors.
“In Western Canada, emissions are smaller, so the emissions reductions are smaller, as compared to Ontario, and Quebec,” says Bruulsema. “And then, specifics of the farm – the soil texture, the landscape and the drainage of the soil – also has effects.”
There is also value to the grower in investing in inhibitor products since it will increase fertilizer efficiency which will increase yields by a small amount without much cost savings.
Reliable information informs policy and is valuable to researchers who are trying to measure practice efficiencies. Bruulsema knows this can be controversial for farmers, but more data needs to be collected and shared, even just with a trusted aggregate rather than a government organization.
“Someone needs to know what’s been done where, so that the science-based models used to estimate greenhouse gas emission have reliable information on what’s been done so that they can predict what the benefit of those practices is in terms of mitigating environmental problems.”
Policy Needs
Federal nitrogen reduction policy has been keeping Bruulsema busy for the last few years. The government announcement in December 2020 was the first anyone in the fertilizer industry heard about plans to set a reduction target, and collaboration with the industry evolved rather slowly.
“We’ve successfully had some good meetings where we exchanged perspectives on how realistic that target was to achieve and what were the obstacles in reaching that target,” he says.
The government has already recognized the cost-sharing potential of nitrogen inhibitors since there are large reductions of emissions without the direct benefit to farmers.
“Nitrous oxide doesn’t have any negative effects directly, specifically on that farm, so it’s really a societal benefit by reducing nitrous oxide emissions. Those are products that are worthy of cost sharing,” says Bruulsema.
Further discussion is happening on which nitrogen inhibitors would be chosen for a cost-sharing program. “Not every product on the market that has the claim to be a nitrification inhibitor is necessarily as efficacious as another. So, there’s a lot of work to be done to sort out some of those questions.”
If farmers are going to reduce their nitrogen inputs, it must be done without “jeopardizing product productivity and profitability of farmers,” says Tenuta. They are working at the University of Manitoba to understand how these costs become barriers to adoption.
Another barrier to adoption is government mandates. This does not sit well with farmers, he says, but if adopting a practice will help farmers save money on their fertilizer bill, that becomes more of an incentive for adoption.
Other Emission Factors
While fertilizer reduction practices have been important to profitability and minimizing losses, Bruulsema also encourages other indirect emission reduction practices, like planting timing, controlling weeds, nitrogen-fixing plants in the crop rotation and avoiding soil compaction.
One other point Bruulsema stresses is that the industry itself is focused on sustainable and environmentally friendly fertilizer production. Development of green and blue ammonia products have become a focus of the industry, with the production process getting its own carbon footprint overhaul through renewable energy sources. There is no clear date for their release into Canadian markets, but Bruulsema is expecting new products in the next three to five years. However, availability and effective pricing has already been a challenge for the industry.
“We need to be prepared for a future where we’re not just simply using the same products that we are used to using now, particularly urea.”