Key Findings of the Canadian 4R Research Network
After a three year independent research project engaging nine leading researchers from across Canada, the 4R Research Network has provided much needed scientific evidence to support the efficacy of the best management practices (BMPs) associated with 4R Nutrient Stewardship (Right Source @ Right Rate, Right Time, Right Place®). These BMPs enable Canadian growers from coast to coast to increase the productivity of their farms while improving their environmental sustainability by reducing losses to air, water and soil.
The interactive map below offers insights into the researchers’ projects and their findings.
Dr. Claudia Wagner-Riddle
University of Guelph
Can application of enhanced efficiency fertilizers at planting reduce nitrogen losses from grain corn production in Ontario?
Nitrogen (N) is a key nutrient input for sustaining high crop yields, but fertilizer N uptake efficiency in crops is relatively low. Part of the applied N that is not taken up by crops is vulnerable to losses such as nitrate leaching and nitrous oxide emissions. The overall goal of this project is to determine how Right Time and Right Source practices for N fertilizer management affect N losses, specifically in grain corn in Ontario.
Dr. Craig Drury
Agriculture and Agri-Food Canada
Can the combined effects of nitrogen fertilizer placement and enhanced efficiency fertilizers reduce nitrogen losses from grain corn production in Ontario?
Corn producers often apply nitrogen (N) fertilizer by either streaming urea-ammonium nitrate (UAN) or broadcasting urea. They are considering adding inhibitors to reduce losses of applied N. Compared to other N sources, urea and UAN fertilizers have higher risks of ammonia loss. As with other N sources, denitrification and nitrous oxide (N2O) losses can also be substantial. The objectives of this project are to measure the impact of these N sources, including their timing and placement, on yields, ammonia loss and nitrous oxide emissions.
Dr. David Burton
Can the use of in-season foliar urea increase the efficiency of nitrogen use and reduce nitrous oxide emissions and nitrate leaching in potato production in Atlantic Canada?
In recent years it has become increasingly popular for potato producers in Atlantic Canada to include urea in the foliar applications of fungicides. Producers believe this practice sustains their potato crop through periods of water stress and allows for more rapid recovery following a precipitation event.
This urea application is not considered as part of their nitrogen (N) fertility program and is applied in addition to the recommended rates of N fertilizer at planting. This project examined the potential to reduce the amount of N fertilizer added at planting in situations where foliar urea will be applied to the crop. It evaluated whether using in-season foliar urea in combination with reduced N fertilizer rates at planting is an effective practice for sustaining potato yields and improving N use efficiency while reducing nitrous oxide emissions and nitrate leaching.
Dr. Mario Tenuta
University of Manitoba
Enhanced efficiency fertilizer technologies to reduce nitrous oxide emissions from cropped soils in Prairie Canada
This prairie province-wide project seeks to assess the environmental and agronomic benefits achieved through grower adoption of enhanced efficiency nitrogen (N) fertilizer technologies, applied in the fall or spring. The application of N fertilizers to agricultural land, and resulting emissions of nitrous oxide (N2O), have been identified as a major driver impeding greenhouse gas reductions for the agriculture sector.
It is important to develop methods to reduce N2O emissions from cropped land after N fertilizer applications. This project is evaluating the benefit of timing of N fertilizer application (fall vs. spring), and use of enhanced efficiency fertilizer (EEF) products for urea and anhydrous ammonia N fertilizers for reduced N2O emissions.
Dr. Miles Dyck
University of Alberta
Nitrogen stabilizers to enhance nitrogen use efficiency and reduce greenhouse gas emissions
Nitrogen (N) is a very reactive element in the environment once it is fixed from di-nitrogen gas (N2) into a hydrogenated form, i.e. ammonia (NH3), or oxidized forms such as nitrite (NO2-) or nitrate (NO3-). Part of the reactive properties included affect N fertilizers applied to agricultural soils. There are loss mechanisms such as volatilization into the air of NH3 after applications of urea fertilizers, leaching of NO3- down through soils into groundwater or into tile drain systems, and or denitrification of NO2- or NO3- into the atmosphere as N2 or nitrous oxide (N2O) gases. This later denitrification product, N2O, being one of the greenhouse gasses.
The main objective of this project is to assess the effect of various commercially available forms of stabilized N on nitrous oxide (N2O) emissions, leaching, nutrient use efficiency (NUE), and crop yield response in cereal and oilseed crops.
Dr. Miles Dyck (Lethbridge)
University of Alberta
Coordinated nitrogen and sulphur management in Sulphur-deficient soils
Approximately, 60 per cent of the current increase in atmospheric nitrous oxide (N2O) emanates from agricultural soils. There is significant evidence that N2O emissions increase in direct proportion to the sum of fertilizer and non-fertilizer nitrogen (N) inputs in agricultural and non-agricultural ecosystems, but other factors such as soil moisture and temperature, fertilizer N type/placement, accompanying fertilizer applications, crop type/rotation, inclusion of legumes, lime applications, microbial community diversity and tillage also contribute to the variability of N2O emissions. It has been shown that long-term N plus sulphur (S) fertilization increased soil organic matter content compared to N fertilization without additional S fertilization in the S-deficient soils at the Breton Plots in west-central Alberta. There are few examples of long-term management effects or management legacy effect on current annual or growing season N2O emissions. This research activity will underpin farming flexibility as it will examine the agronomic and environmental impacts of a wide range of N and S management options.
Dr. Jeff Schoenau
University of Saskatchewan
Effect of broadcast versus banded phosphorus application on fate of applied P in soil and in snowmelt water flow
Phosphorus (P) moves very slowly in soil and is often called immobile. In soils that are somewhat deficient in P, it is important to place the P so that the roots of the crops grow into the area where the P fertilizer is placed.
The objective of this study is to compare various placement methods of P fertilizer in relation to the seed row. These treatments included pre-plant banding below the seed row, seed row placement during the planting operation, pre-plant broadcast and incorporation, and pre-plant broadcast without incorporation.
Dr. Ivan O’Halloran
University of Guelph
Impact of degree of fertilizer and manure incorporation and timing of first runoff event on phosphorous losses in surface runoff
Traditional teaching on phosphorus (P) behavior in soil emphasized its retention, and therefore conservation programs to reduce P loss from agricultural soils focused on reducing soil erosion. More recent observations in the Great Lakes watershed suggest that losses of dissolved forms of P are increasing. Combined trends in tillage practices, along with timing and placement of fertilizer and manure, may drive this increase in loss of soluble P.
This project aims to assess the effect of timing and placement on losses of dissolved and particulate forms of P. The project has three major objectives: i) controlled runoff studies assessing fertilizer and manure P placement/incorporation; ii) controlled runoff studies assessing commercial fertilizer placement and timing to first runoff event; and iii) a field study relating runoff and incorporation methods on P losses from fertilizer and manure.
Dr. Nicolas Tremblay
Agriculture and Agri-Food Canada
Development of decision support mechanisms for 4R optimization of nitrogen fertilization placement, rate and timing based on the integrated use of soil, weather and market data
Nitrogen (N) fertilization provides essential benefits for food production, but its optimal management is subject to a high level of complexity. The fertilizer industry, agronomists, consultants, and farmers recognize the 4Rs as the basis for optimum fertilization, but their implementation is knowledge-intensive and site-specific. For a full implementation of the 4R strategy for N, it is necessary to address the risks and opportunities at the field-scale with respect to weather and its interactions with soils and other management factors.
Dr. Alison Eagle
How does 4R Nutrient Stewardship affect social, environmental, and economic outcomes?
The goal of this project was to review resources and define a suitable framework for determining the social, environmental, and economic outcomes of 4R Nutrient Stewardship in Canada. Four major sets of guidelines were reviewed: 1) Integrated Environmental Assessment, United Nations Environment Program (2009); 2) the Canadian Cost Benefit Analysis Guide, Treasury Board of Canada Secretariat (2007); 3) Sustainability Reporting Guidelines, Global Reporting Initiative (2011); and 4) Framework for Assessing Effects of the Food System, Institute of Medicine and National Research Council (2015).
We concluded that the key ingredients for assessment are: 1) establishing boundaries, possibly with multiple scales; 2) establishing baseline and possible scenarios; and 3) comparison of scenarios, quantifying economic, environmental and social impacts in terms of costs and benefits, expressed in dollars per unit of nitrogen or phosphorus.