The Importance of Reducing On-Farm Nitrogen Losses

As governments enact carbon-pricing strategies to address climate change, reducing greenhouse gas emissions on-farm becomes more important. Effective use of stabilized nitrogen fertilizers offers tangible environmental benefits.

There is no doubt that the Canadian government’s commitment to reduce greenhouse gas emissions 30 percent by 2030 (from 2005 levels) will impact farmers.
Participation is no longer optional. Ottawa has plans to impose a greenhouse gas reduction strategy on any province that does not design and implement its own. Nationally, the carbon price will be set at $10 per tonne in 2018.
Carbon-pricing programs have already been introduced in Ontario, Quebec and Alberta, and Manitoba is making plans to implement a carbon tax. British Columbia has had a carbon tax since 2008.
Some programs include exemptions on direct costs, and some governments offer credits to farms to offset costs. Regardless, carbon now has a price tag and, while the dollar figure attached may change, the legislation designed to reduce greenhouse gas emissions is likely here to stay.
Variations by province make it hard to estimate how much carbon pricing will cost farmers. So what changes can farmers consider to reduce their emissions and counteract carbon pricing?
One strategy that has shown success in the U.S., with benefits both to farming operations and to the environment, is to maximize the benefit of applied nitrogen fertilizer, reducing greenhouse gas emissions related to fertilizer losses.

Reduce nitrogen losses to reduce emissions

Soil nitrogen losses are part of the Earth’s nitrogen cycle, explains Tom Jensen, fertility expert with International Plant Nutrition. “Natural loss processes of nitrogen from the soil include leaching, ammonia volatilization and denitrification,” he says.
After application, nitrogen fertilizer converts in the soil to the nitrate form, which has the potential to leave the soil either by gassing off (denitrification) or leaching out in to groundwater.
The denitrification process increases greenhouse gas emissions and reduces fertilizer efficiency. “It’s important to manage applications of nitrogen fertilizers and livestock manure to minimize excessive and unwanted losses,” Jensen says.
Without careful management, farmers’ fertilizer investment may, quite literally, blow away. “Growers underestimate the amount of nitrogen they lose,” says Jason Smith, market development specialist with Corteva AgriScience. “Whether they band or surface apply it, their losses are substantially higher than they believe.”

Ways to reduce nitrogen losses

Some ideas governments can support to help reduce nitrogen losses on farms include adopting 4R nutrient management practices, investing in technology that will improve fertilizer efficiency and including crops that fix nitrogen in their rotation.
Policies supporting these strategies would reduce greenhouse gas emissions and increase the amount of food produced per unit of emission.
“A good goal is to ensure as much of the available nitrogen as possible is used to grow crops and maintain soil health, and that the least possible amount is lost to the environment through leaching and denitrification,” says Smith.
Following a nutrient management plan is one way to support effective nitrogen use on-farm. A nutrient management plan will carefully consider the 4Rs of nutrient stewardship: right source, right rate, right time and right place.

  • Right source involves ensuring fertilizer includes a balanced supply of the essential nutrients, considering both naturally available sources and the characteristics of specific products, in plant available forms.
  • Right rate requires an assessment of soil nutrient supply and plant demand to ensure the best amount of fertilizer is applied.
  • Right time considers the dynamics of crop uptake, soil supply, nutrient loss risks and field operation logistics.
  • Right place addresses root-soil dynamics and nutrient movement, and requires the consideration of field variability to meet site-specific crop needs and limit potential losses.
  • Including a nitrogen-fixing crop in the farm’s rotation is also a good option. Nitrogen-fixing crops such as field peas, fava beans and lentils fix nitrogen out of the environment in a plant available form in the soil, reducing the amount of applied nitrogen needed to support healthy crop yields the following year.

Nitrogen stabilizers reduce greenhouse gas emissions

Another way to reduce greenhouse gas emissions and increase fertilizer efficiency is to use a nitrogen stabilizer with fertilizer applications.
Nitrogen stabilizers like N-Serve™ or eNtrench™ keep more nitrogen in the root zone, increasing yield potential for the current crop, supporting environmental stewardship by reducing nitrogen losses to the environment, and ensuring growers get the most out of their fertilizer investment.
“Nitrogen stabilizers inhibit the bacteria that initiates the conversion of nitrogen to the nitrate form that is susceptible to denitrification and leaching,” Smith says.
“Growers who use N-Serve or eNtrench with their fertilizer find there is a greater available nitrogen supply in the soil in June and early July to support plant growth,” says Lorne Thoen, product manager with Corteva AgriScience. “Trial results show, on average, 21 percent more nitrogen is retained in the root zone.”
Having more nitrogen available to crops can result in a significant return on investment. “In field trials we saw an average of eight percent yield increase in canola treated with N-Serve or eNtrench. Wheat yields increased five percent on average,” says Smith.
The ROI goes further than yield increases, though. There is peace of mind for growers who know they are supporting environmental stewardship through their farming practices, and the use of N-Serve and eNtrench reduces greenhouse gas emissions by 51 percent and nitrogen leaching by 16 percent.

US case study: Award-winning chemistry stabilizes nitrogen

In the U.S., the Corteva AgriScience product Instinct® won the EPA Presidential Green Chemistry Award in 2016 because of its proven ability to protect the environment by reducing nitrogen losses and maximizing the benefits of applied nitrogen in the soil.
“Instinct, available in Canada under the trade name eNtrench, is designed to make nitrogen fertilizers work more effectively for farmers and the environment,” says Thoen.
In less than five years, the number of acres treated with stabilized nitrogen has grown more than five-fold. Keeping applied nitrogen in the soil with nitrogen stabilizers has kept as much as 664,000 metric tons of carbon dioxide out of the air.*
In fact, government cost-sharing programs are available through the U.S. Department of Agriculture to help support growers’ use of nitrogen stabilizers.

Stabilizer use begins to take hold in Canada

Nitrogen stabilizer use has become common practice in the U.S. In Canada, it is expected that stabilizing nitrogen will be a broadly adopted practice in coming years as a result of the growing emphasis on reducing greenhouse gas emissions to support a healthy environment.
“By using a nitrogen stabilizer like N-Serve or eNtrench, growers can rest easier knowing their applied nitrogen will be available when their crop needs it most,” Smith says. “They can also have peace of mind knowing they are using the best nitrogen management practices to reduce greenhouse gas emissions.” 

Stabilizers are part of an effective nitrogen management plan

As legislation around carbon pricing continues to take effect in different provinces across the country, one thing is certain: Growers will benefit from introducing effective nitrogen management practices on their farm.
Effective nitrogen management has great potential to reduce negative environmental effects while also maximizing yield.
“Growers value their role as environmental stewards, and effective nitrogen management supports that position. As greenhouse gas emission reduction strategies become the norm, finding ways to increase yields while decreasing emissions will be very important,” says Smith.
There is also the possibility that government legislation will in the future support the use of stabilizers in Canada, as it already does in the U.S.
“Higher input costs as a result of carbon pricing will be a reality. Reducing emissions and seeking higher yields with support from stabilized nitrogen is one positive way growers can respond,” says Thoen.

*Actual reduction of carbon dioxide emissions in 2014, based on data from the U.S. Environmental Protection Agency.

Nitrogen Stabilizers | Corteva Agriscience