Management practices directly related to synthetic fertilizer application continue to be adapted by industry to lower risk loss and reduce greenhouse gas (GHG) emissions.
On this page, we cover these suggestions for nutrient management practices that can enhance fertilizer use efficiency and limit GHG creation.
Band your fertilizer
The best method for applying N fertilizer to a crop is banding. Banding in or near the seed row ensures that the fertilizer is accessible to the crop roots when they need it most. When applied in a concentrated band, less fertilizer surface area is accessible to soil microorganisms, preserving the fertilizer in ammonium (NH4+) form for a longer. This reduces leaching and denitrification potential.
When banding is not possible, fertilizer should be incorporated into the soil shortly after application.
In the case of perennial crops or winter wheat, where incorporated or injection is not an option, N fertilizer is best broadcast shortly before a rainfall.(1)
Use slow-release nitrogen fertilizer
Slow release fertilizers do just that – release nutrients slowly over time, making N available to the crop when it is most needed. Crop roots develop slowly after seeding and slow-release fertilizers gradually break down, supplying nutrients in synchrony with crop growth. Fertilizer loss is lowered due to less leaching or denitrification risk because growing roots consume almost all N.
Slow-release fertilizers are more expensive, so economics may limit their use to high value crops.(2)
Use urease inhibitors and nitrification inhibitors
Urease and nitrification inhibitors reduce the risk of N losses from a variety of paths, including N2O emissions from denitrification. Inhibitors are an affordable solution for farmers to improve the efficiency of N uptake when broadcast applications are necessary.(3)
- Urease inhibitors prevent volatilization of surface-applied area or UAN solutions.
- A nitrification inhibitor slows the conversion of ammonia-N to nitrate-N, keeping the fertilizer in an inaccessible form for a longer period of time.
For more information, download our publication “Farming in a Changing Climate in Manitoba – Crop Edition (2013)“