Current Research

The Applied Soil Ecology Lab has highly productive and impactful research programs with several important agricultural foci: soil ecology, nematology, and the relationship between nutrient management and greenhouse gas emissions. Research projects are carried out under the leadership of Mario by our graduate students and expert technicians, with the help of undergraduate summer research students. Our research programs benefit from collaborations with many individuals from the academic community, private industry, and government agencies.

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Industrial Research Chair 
Long Term Field Sites
4R Nutrient Stewardship

4R Nutrient Stewardship Industrial Research Chair Program

The Industrial Research Chair in 4R Nutrient Stewardship is a 5-year research program that aims to fill important gaps in knowledge, training, and adoption of 4R practices by:

  1. Evaluating how nitrification inhibitors stabilize fertilizers and reduce N2O emissions and N losses;
  2. Initiating long-term studies to contrast the benefit of 4R practices on direct N2O emissions and indirect emissions as NH3 and leaching N losses on different soils;
  3. Improving models of N2O emissions to include 4R practices;
  4. Summarizing farm survey information to gauge current use of 4R practices; and
  5. Synthesizing findings of this IRC and other studies to forecast the extent by which the adoption of 4R practices can help Canada achieve greenhouse emission reduction commitments.

Read more about the IRC program and projects here.

Long Term Field Sites

Trace Gas Manitoba

Established in 2005, TGAS-MAN is a long-term site that tests farming practices and their impact on greenhouse gas emissions, with the goal of providing empirical data to guide best management practices to lower emissions without compromising profitability. Which farming practices are tested have changed over time to address current questions as technology and farming practices evolved. These include tillage intensity, annual vs perennial cropping, fall vs spring application of anhydrous ammonia, cover cropping, and applying fertilizers with and without nitrification inhibitors. Read more about TGAS-MAN here.

Trace Gas Harvest Moon

TGAS-HM was established in 2022 and is operated in parallel with TGAS-MAN with the key difference of being located on lighter well-draining soils more typical of the Canadian Prairies than the poorly draining clay soils of TGAS-MAN. These lighter soils have opened the opportunity to study indirect losses of nitrogen through nitrate leaching. The first project taking place at TGAS-HM is a study of the effect of nitrification inhibition on whole-year direct and indirect N2O emissions. Read more about TGAS-HM here.

NCLE Long Term Field Site

Since 2007, a multidisciplinary team has used this site to compare how annual and mixed cropping systems respond to different types of manure and manure management practices. The goal is to reveal how these responses change over time, and how the interplay of crops and manure can be optimized for best crop growth and minimal loss of nutrients.

From 2007 to 2015, the team compared outcomes when manure is applied either annually, at rates to meet crop N requirements, or intermittently, at rates to match crop P removal over several years. In the second phase, the scope expanded to measure the capacity of the manured soil to continue to release plant-available nitrogen, phosphorus and other essential nutrients after manure applications stop and how this affects crop yield. In the third phase, now underway, research at the site has moved into the realm of soil health improvement. The team is exploring how a suite of soil-building practices can improve nitrogen uptake, phosphorus draw-down, carbon retention and additional soil health indicators while also reducing greenhouse gas emissions. Read more about the NCLE Long Term field site here.

4R Nutrient Stewardship Projects

Can Nitrification Inhibitors and Reduced Fertilizer Nitrogen Rates be Practical Means to Reduce GHG Emissions from Field Crop Production in Manitoba?

Years: 2023 – 2026
Principle Investigator: Mario Tenuta (U of Manitoba)
Co-Applicants: Manasah Mkhabela (Manitoba Agriculture), Katherine Stanley (Manitoba Crop Alliance)
Funding Program: Discovery Grant (Individual) Program
Funding Sources: NSERC

4R N Management Practice: Rate and Source
Summary: Manitoba farmers would benefit from implementing practical and economical ways to reduce N2O emissions from field crop production. This study will investigate two such approaches: reducing nitrogen (N) application rates and including nitrification inhibitors with fertilizer N. Field trials comparing agronomics and N2O emissions will take place during three growing seasons at four Crop Diversification Centres in Manitoba, for a total of 12 site-years. Experimental treatments include sustained additions of 100, 90 and 70% of recommended N, and 100% N application with and without the dual nitrification and urease inhibitor SuperU®.

Positioning Manitoba’s Fresh Potato Industry for Improved Sustainable Production

Years: 2023 – 2026
Principle Investigator: Tracy Shinners-Carnelley (Peak of the Market Ltd.)
Co-Applicant: Mario Tenuta (U of Manitoba)
Funding Sources: Manitoba Agriculture, Peak of the Market Ltd., and Gaia Consulting

4R N Management Practice: Rate and Time
Summary: Combining potato genetics and 4R practices should position the Manitoba potato industry to experience improved sustainable production and reduced environmental impact. This project aims to quantify reductions in nitrous oxide emissions achievable by planting an improved nitrogen use efficient fresh market potato cultivar in concert with implementing 4R nitrogen management practices, without sacrificing yield or potato quality.

A field trial will be conducted during three growing seasons at the Peak of the Market Research Site (Winkler, MB). Experimental treatments include additions of 100, 85, 70, and 50% of recommended N, applied as urea alone by incorporation at pre-plant or with a nitrification inhibitor by split application at pre-plant and hilling.

Precision 4R Management: Improving Nitrogen Use Efficiency, Greenhouse Gas Emissions and Production Economics of Canola

Years: 2023 – 2026
Principle Investigator: Mario Tenuta (U of Manitoba)
Co-Applicants: Richard Farrell (U of Saskatchewan), Chris Holzapfel (Indian Head Agricultural Research Foundation), and Cory Willness (Croptimistic Technoclogy Inc. and CropPro Consulting)
Funding Program: AAFC Sustainable Canadian Agricultural Partnership (SCAP) – Canola Cluster

4R N Management Practice: Rate and Source
Summary: Commercial farm fields are heterogeneous in terms of landscape position and soil properties, two factors which influence yield response to and nitrous oxide emissions from nitrogen fertilizer additions. To address this spatial variability, Precision Agriculture was developed to improve nutrient use efficiency by matching N addition-induced yield response to landscape position and soil properties within a field. For example, management zones for specific nitrogen fertilizer rates in a field based on soil properties, water regime, and topography is the basis of SWAT MAPS. This project proposes to determine the extent to which N2O emissions reductions and improved profitability of canola farms can be achieved by combining the Precision Agriculture practice of tailoring N rates to management zones with the 4R Management practice of using a nitrification inhibitor.

Three field trials will take place over three growing seasons on commercial fields in the Thick Black, Thin Black, and Dark Brown soil regions of Manitoba and Saskatchewan. Experimental treatments include application of conventional urea at a conventional rate, variable application rates of conventional urea, variable application rates of a variable source (conventional urea vs urea with a nitrification inhibitor), and applying a variable source at reduced application rates to compensate for the additional cost of using an inhibitor. Treatment management zones will be determined using management zones identified by SWAT MAPS.

Cover Crops and 4R Strategies to Mitigate Greenhouse Gas Emissions

Years: 2023 – 2028
Principle Investigator: Craig Drury (AAFC Harrow)
Collaborators: Mario Tenuta (U of Manitoba), Claudia Wagner-Riddle (U of Guelph), Joann Whalen (McGill U), Ikechukwu Agomoh (AAFC Fredericton), David Pelster (AAFC Québec), Ward Smith (AAFC Ottawa), Lori Phillips (AAFC Harrow), Xueming Yang (AAFC Harrow), Alfons Weersink (U of Guelph)
Funding Program: AAFC Sustainable Canadian Agricultural Partnership (SCAP) – Canadian Field Crop Research Alliance (CFCRA) Cluster
Funding Sources: CFCRA (including Atlantic Grains Counctil, Producteurs de Grains du Québec, Grain Farmers of Ontario, Manitoba Crop Alliance, Manitoba Pulse & Soybean Growers, Saskatchewan Pulse Growers, Prairie Oat Growers Association, SeCan, and FP Genetics), Grain Farmers of Ontario, Fertilizer Canada, MAPAQ-PALCCA, NSERC Alliance, NSERC Discovery Grant, and AAFC[MP1] 

4R N Management Practice: Source
Summary: Two major environmental issues facing Canadian agriculture are (1) reduced carbon inputs associated with annual cropping, increased planting of soybean, and less frequent growing of cereal and perennial forage, and (2) environmental losses of nitrogen, including nitrous oxide emissions, nitrate leaching, and ammonia volatilization, associated with N fertilization. Cover cropping can increase soil organic C by increasing annual primary production, and implementing 4R nutrient management strategies can reduce N2O emissions from fertilizer use. This project will investigate both these practices in major corn growing regions in Canada. Corn was chosen because it requires high nitrogen inputs relative to other crops and is a major agricultural commodity in Canada with recent increases in area planted.

Field trials will include 8 core treatments evaluated in 6 regions (South Central Manitoba; Elora, ON; Woodslee, ON; Ste. Anne de Bellevue, QC; Quebec City, QC; and Fredericton, NB) during 4 growing seasons. These treatments include using cereal rye as a fall over-winter non-legume cover crop and a side-dress injected urea ammonium nitrate (UAN) fertilizer solution with combined urease and nitrification inhibitors under no tillage and conservation tillage.

There are four main objectives: (1) determine the impact of cover crops and combined urease & nitrification inhibitors under no-tillage and conservation tillage treatments from 6 sites (4 Provinces) on growing-season N2O & CO2 emissions over 4 years and on agronomic parameters (e.g. nitrogen uptake and corn yields) and economics over 5 years, (2) increase carbon stocks and the labile C fractions using cover crop and inhibitor treatments, (3) model the 24 site-years of data using the Canada DeNitrification-DeComposition (Canada DNDC) model to understand integrated agronomic and environmental impacts and scale up to the provincial levels in MB, ON, PQ and NB, and (4) evaluate how the microbially-mediated carbon and nitrogen cycling processes that underpin soil health are altered by combined cover crop and inhibitor treatments.

A Prairie Assessment of Nitrogen Stabilizers and Split Fertilizer Application in Sustaining Spring Wheat Yield, Protein, and Production Economics While Reducing Nitrous Oxide Emissions

Years: 2023 – 2028
Principle Investigator: Mario Tenuta (U of Manitoba)
Co-Applicant(s): Mervin St. Luce (AAFC Swift Current), Xiying Hao (AAFC Lethbridge), Brian Beres (AAFC Lethbridge)
Collaborators: Hiroshi Kubota (AAFC Lacombe), Guillermo Hernandez-Ramirez, (U of Alberta), Bill May (AAFC Indian Head), Tristan Skolrud (U of Saskatchewan)
Funding Program: AAFC Sustainable Canadian Agricultural Partnership (SCAP) – Wheat Cluster

4R N Management Practice: Rate, Source, Time
Summary: Past research with spring wheat and other crops has observed that nitrification inhibitors and urease inhibitors can significantly decrease direct N2O emissions from soil and indirect emissions from ammonia volatilization, respectively. This research is so far limited to a few areas of the Prairies. Research has also shown that split application of N can decrease emissions compared to addition at seeding for corn and potato; similar research has not been conducted for wheat. This project will carry out a pan-Prairie field study to determine the benefit of combinations of split application, inhibitor-treated urea, and reduced rate urea addition to agronomic performance and the reduction in N2O emissions from Canadian Western Red Spring Wheat, the largest class of spring wheat produced in the Prairies.

The specific objectives are to determine if (1) split application of urea (60% banded at planting and 40% top-dressed in-season) can reduce emissions without compromising grain yield and protein content, (2) urease and nitrification inhibitors can reduce emissions and N losses without compromising timely nitrogen availability to the crop, and (3) increased nitrogen use efficiency allows for reduced fertilizer N application rates, thereby compensating for the incremental costs of split application and inhibitor usage. The study will be conducted at five locations across the Canadian Prairies during four growing seasons. The sites encompass the diverse agroecological conditions of the Prairies and four major soil zones. Field trials will be a factorial combination of the following 4R management practices: Timing (at plant vs split application), Source (inhibitor vs none), and Rate (70, 90, 100%).

Nitrification Inhibition on Greenhouse Gas Emissions, Soil Health, and Barley Performance

Years: 2023 – 2028
Principle Investigator: Linda Gorim (U of Alberta)
Co-Applicant(s): Malinda Thilakarathna (U of Alberta), Ludovic Capo-Chichi (U of Alberta), Scott Change (U of Alberta)
Collaborators: Mario Tenuta (U of Manitoba), Richard Farrell (U of Saskatchewan)
Funding Program: AAFC Sustainable Canadian Agricultural Partnership (SCAP) – Barley Cluster

4R N Management Practice: Source
Summary: Nitrification inhibitors (NIs) are available to producers to reduce nitrogen (N) losses with applied granular urea. However, producers lack information on whether the use of NIs result in lower required N application rates for popular current and upcoming feed and malting barley varieties, negative effects on soil microbiomes and reduce nitrous oxide (N2O) emission, as well as improved agronomic performance and net return for barley production. Therefore, the objectives of this project are to evaluate the effects of untreated urea vs urea treated with an NI, specifically eNtrench, applied at recommended and reduced rates on (1) agronomic performance of feed and malting barley varieties, (2) soil health under feed and malting barley cropping systems, and (3) GHG emissions under feed and malting barley cropping systems.

Field trials will be carried out at four sites for three growing seasons across the Prairies to achieve the stated objectives. The sites are in Manitoba, Saskatchewan, and Alberta on Black, Brown, Dark Brown Chernozem, and Vertisol soil zones, each with different agro-climatic environments and soil properties. This research will provide critical information for developing best management practices for reducing GHG greenhouse gas emissions and improving nitrogen use efficiency (NUE) in Western Canadian cropping systems.


Protecting Manitoba’s Soybean Industry from Soybean Cyst Nematode

Years: 2023 – 2026
Principle Investigator: Mario Tenuta (U of Manitoba)
Co-Applicant(s): Daryl Domitruk (Manitoba Pulse & Soybean Growers)
Collaborators: Dennis Lange (Manitoba Agriculture), Elisabeth Harms (Manitoba Pulse & Soybean Growers), Jason Voogt (Field2Field Consulting)
Funding Program: AAFC Sustainable Canadian Agricultural Partnership (SCAP)
Funding Source: Manitoba Pulse & Soybean Growers

Summary: This study aims to protect the growth of the Manitoba soybean industry against a detrimental new pest, soybean cyst nematode (SCN), which is the most economically damaging pest and disease of soybean in North America. In Manitoba, it is relatively new. We propose to limit the risk to soybean production in Manitoba from SCN by determining its present distribution, effectiveness of control products, if it is a threat to edible beans, and if it is resistant to current soybean varieties.

Last Updated: September 21, 2023

Welcome to the Applied Soil Ecology Lab at the University of Manitoba