Discovering the optimal rate of a dual-inhibitor N-fertilizer for maximum N2O emissions reduction

Term: 3 years, ending March 2025
Status: Ongoing
Researcher(s): Reynald Lemke, Agriculture and Agri-Food Canada; Richard Farrell and Kate Congreves, University of Saskatchewan
SaskCanola Investment: $27,605
Total Project Cost: $276,050
Funding Partners: Agriculture Development Fund, Western Grains Research Foundation, Sask Wheat

Project Description

Consumers are increasingly concerned about the safety and sustainability of agricultural production practices. In response, many corporations now require suppliers to demonstrate the sustainability of their products and practices. In view of the urgent need to limit greenhouse gas emissions to the atmosphere in an effort to avoid dangerous climate change, greenhouse gas (GHG) emissions have become a key sustainability metric for agricultural products and an important consideration in the marketplace. This is of particular importance for the agricultural industry in Saskatchewan which contributes more than 80% of the province’s total N2O emissions. The great majority (~88% ) of these emissions are directly related to the use of N fertilizers (Environment Canada, 2018). Thus, there is an ever increasing need to identify practical tools that Saskatchewan producers can employ to help them to maintain or improve yields while simultaneously reducing N2O emissions; and to be able to quantify those benefits in a credible, verifiable manner.

Purpose

Producers are coming under increasing societal, market, and regulatory pressures to reduce N2O emissions from the use of N fertilizers. Determining optimal combinations of rate and a dual-inhibitor product will provide a pathway for producers to respond to these pressures without jeopardizing yield. Data generated by this research will yield experimentally-based N2O emission modifiers that are appropriate for incorporation into Nitrous Oxide Emissions Reduction Protocols and the National Inventory Report which will be critical in order to comply with potential regulatory requirements and/or participate in carbon off-set protocols.

Goal

This project is intended to address the following questions:

1. Can a DI N-fertilizer product be applied at a reduced N-rate as compared to urea while maintaining equivalent yield?

2. How much can the N application rate of an DI N-fertilizer product be reduced before negatively impacting yield relative to a standard application rate of urea?

3. What is the maximum N2O reduction that can be achieved with an DI N-fertilizer product while maintaining crop yields equivalent to a standard application rate of urea?

Objectives

1. Determine the maximum N2O emissions-reduction that can be achieved with a dual-inhibitor N-fertilizer as compared to urea.

2. Determine maximum N-rate reduction possible with dual-inhibitor N-fertilizer that maintains optimal yields of canola and wheat.

3. Determine the agri-environmental optimum N rate for urea and a dual-inhibitor N-fertilizer as an N source for canola.