GHGMP News Releases
Nutrient balance makes good economic and environmental sense
Indian Head, Sask. October 19, 2004
While the production of nitrous oxide from routine farming practices isn't routine kitchen-table conversation on most farms, the greenhouse gas does factor into both economic and environmental considerations for producers.
If farmers across the country can minimize production of nitrous oxide, it means they're likely maximizing the benefits of their fertilizer dollar, say soil and environmental specialists. Nitrous oxide, one of the most harmful of the greenhouse gases, can develop when surplus nitrogen is left in the soil.
While the amount of gas released varies with the climate across the country, it's most commonly associated with surplus nitrogen under waterlogged soil conditions, explains Doug McKell, executive director of the Soil Conservation Council of Canada (SCCC). That combination can develop in any region of the country depending on the season or the particular moisture patterns in a year. Nutrient balancing which means using management practices which better match the amount of available nutrients with crop requirements is a key tool in reducing the greenhouse gas.
For a more detailed look at management techniques that can reduce nitrous oxide production, visit the SCCC Website at www.soilcc.ca and check out articles under the Greenhouse Gas Mitigation Program for Canadian Agriculture (GHGMP). The three-year federal program launched in 2003 has established dozens of on-farm demonstrations across the country to promote practical and environmentally sound production practices.
High moisture conditions found in parts of Manitoba and through to the East Coast, not only increase the risk of leaching nitrogen and other nutrients from the soil, but under high water content conditions, the fertilizer also releases nitrogen to the atmosphere. The process known as denitrification creates a direct economic loss of fertilizer dollars. As well, part of the nitrogen is lost in the form of nitrous oxide, which is one of the most serious greenhouse gases.
Denitrification is the conversion of soil nitrate to nitrogen gases, whether the soil nitrate comes from commercial fertilizer, manure, or fixed by legumes. While not unheard of, denitrification is a lesser known issue over the extensive grain and oilseed growing regions of Alberta and Saskatchewan through to B.C.'s Peace River Region.
In many growing seasons, Prairie producers worry whether there's adequate moisture to make nutrients available to growing crops. Crop fertility strategies not only consider the nutrient needs during the growing season, but often look for ways to bank surplus nitrogen for next year's crop.
Producers in higher moisture areas, on the other hand, worry about too much moisture, and in many parts of Eastern Canada with milder winter temperatures, consider residual nitrogen a disadvantage. The challenge is to use all available soil nitrogen during the growing season and avoid surplus nutrients, which would likely be lost through leaching due to runoff or heavy rainfall events. Similar challenges face B.C.'s Lower Mainland producers.
For producers, dentrification represents an economic loss of as much as two to four pounds of nitrate per acre per day while the soil is in the saturated state. Nitrous oxide emissions can range from 0.5 to four pounds of nitrogen per acre per year depending on moisture and temperature. This range applies to non-manured fields and is likely higher on manured fields.
However, denitrification can be managed, say soil fertility specialists. While farmers can't control the weather they can use management techniques to protect nitrogen and reduce production of nitrous oxide.
The GHGMP supports a broad range of projects across Canada with the goal to promote awareness of agricultural practices that reduce greenhouse gas emissions. Soil Conservation Council of Canada (SCCC) administers the delivery of the soil and nutrient management sector component of the program. For more information on activities, visit the SCCC's Web site at www.soilcc.ca.
For more information, contact:
Doug McKell, Executive Director
Soil Conservation Council of Canada
Indian Head, Sask.
Phone: (306) 695-4212
Jerome Damboise, Program Co-ordinator
Eastern Canada Soil and Water Conservation Centre
Grand Falls, New Brunswick
Phone: (506) 475-4040