FERTILIZER REDUCTION TARGETS A TOPIC OF DISCUSSION FOR CANADIAN FARMERS

BY BECKY ZIMMER

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 kneehigh 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.