Improved nitrogen efficiency across biophysical regions of the Eyre Peninsula
Summary
This project measured nitrous oxide (N2O) emission levels from wheat grown in rotation with canola, pulses and legume pastures in key biophysical regions of the Eyre Peninsula (EP); while assessing best management practices that local farmers can adopt to minimize N2O losses from the use of synthetic fertilizers through the use of cost effective alternative nitrogen (N) sources.
Nitrous oxide (N2O) is a greenhouse gas (GHG) which lasts in the atmosphere for 121 years and has a global warming potential (GWP) 265 times that of carbon dioxide over a 100 year timescale (IPCC, 2014). Agriculture accounts for approximately 80% of Australia’s nitrous oxide emissions (Dalal et al., 2003) This is primarily a result of using nitrogen-based fertilisers on crops and pastures, and the mineralisation of soil organic matter, both leading to the accumulation of soil nitrate (NO3–) an important ingredient in N2O production. The N2O losses represent a loss of N from cropping soils which can reduce farmer profits and contribute to increasing GHG emissions and global warming and ozone depletion.
Key findings:
The N2O emission data from both sites show that emission levels in low rainfall farming systems appear to be lower than levels in medium-high rainfall farming systems, and this is consistent with other studies done in dryland low-medium cropping systems (Barton et al, 2008; Officer et al, 2015; Schwenke et al, 2015). One of the objectives of this project was to confirm or oppose current perceptions that farming systems produce low N2O emission from EP soils (Grace pers. comm.), then use that knowledge to develop principles that can be considered in managing N2O losses in low-medium rainfall farming systems.
Wheat yields following canola, a pulse and legume pasture were not significantly different (P<0.05) and ranged from 2.6 – 2.9t/ha at the low rainfall MAC site, but higher (P<0.05) following lupins (2.9t/ha) than following canola (2.7t/ha) at Wanilla (highest N2O flux site). Integrating a legume into cropping systems on the EP did not compromise wheat yields, reducing synthetic N requirements and ultimately reducing N2O emissions.
Downloads:
Share this project:
You Might Also Like
Young Farmer Peer to Peer Learning Lower EP 2025
AIR EP will establish a group comprised of Lower Eyre Peninsula young farmers (~18-35 years). This group will participate in three field events/workshops featuring speakers on topics that build agricultural,…
Learn MoreBuilding resilience – Break Crop Suitability Across Landscapes (Stage 2)
Upper North Farming Systems and AIR EP have worked to bring this common theme across the 3 farming groups and 4 Node regions together into the one project in 2024.…
Learn MoreRisky decisions and addressing soil constraints on EP
This project has two key objectives that address the priorities of the SA Drought Hub 1. Arming farmers and advisors with tools to assist in decision making that considers risk…
Learn MoreGrowing lentils on challenging soils on Eyre Peninsula
A new 3-year project has been funded by GRDC to explore growing lentils on ‘challenging’ soils across EP. The project, led by AIR EP will fund 4 trials per year,…
Learn MoreDe-risking the sowing program on EP in 2025
SA Drought Hub Project Page
Learn MoreUnderstanding herbicide residue on challenging soil types within the southern region
To develop a better understanding of the nature and scope of herbicide residues issues, paddock surveys will be conducted in soil types of concern in SA. To determine phyto-toxicity thresholds,…
Learn MoreEyre Peninsula internship in applied grains research 2026
To improve the capacity of grains research, development and extension in the Eyre Peninsula region through the employment of an annual intern within local research organisations in 2026. Hosted by…
Learn MoreSustainable Agriculture: Driving growth through innovation and climate responsive practices.
The Eyre Peninsula Sustainable Agriculture Program brings together Agricultural Innovation & Research Eyre Peninsula (AIR EP), the EP Landscape Board, key researchers, industry specialists, and local organisations to deliver a…
Learn MoreImproving crop phosphorus supply on highly calcareous soils using novel sources
This project will develop integrated solutions to improve the delivery of P in challenging calcareous soils with multiple constraints. Those solutions will be developed in a farming systems context so…
Learn MoreCarbon Outreach Project
The Eyre Peninsula Landscape Board (EPLB) is one of eight regional Boards collaborating to deliver the overarching project titled SA Carbon Outreach: Trusted advisors empower all SA land managers. The…
Learn More