A fixed-wing aircraft is used to drop fertiliser on a field. Photo: New Zealand Agricultural Aviation Association
There is much still to know about nitrogen, especially when it comes to nitrate loss and water quality.
"We need to have better discussions and confront the issues and we need to do it more regularly, if we're going to solve the problems that we face," said Professor John Hickford, from Lincoln University's Department of Agricultural Sciences, who organised a recent event unpacking nitrogen's role in the primary sector.
The Nitrogen: Friend of Foe? Forum was put on by the New Zealand Institute of Agricultural and Horticultural Scientists and held at Lincoln University.
Professor John Hickford on the podium at the Nitrogen: Friend of Foe? Forum Photo: Supplied
The discussion was opened by Emeritus Professor Keith Cameron from Lincoln University's Department of Soil & Physical Sciences.
He illustrated the flow of nitrogen from the atmosphere into the soil, through different organisms and oxidation states and onwards through different farming and natural systems.
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"The evidence tells us clearly that nitrogen is absolutely essential for all plants and all animals; without nitrogen we wouldn't be alive.
"Nitrogen can be added to the system in organic forms or mineral fertiliser forms and really it's about the management of those inputs to reduce the leakage from the system," he said.
Photo: Cosmo Kentish-Barnes
Most of the speakers pivoted between agricultural and environmental science, but Professor Jackie Keenan, a researcher in Otago University's Department of Surgery, focused on human health.
She talked about the known risk factors for colorectal (colon) cancer and what might be driving the increased risk of early onset of the disease in Canterbury.
Before Keenan took to the lectern, she said nitrates may be a risk factor but they were "one of many".
"You could get rid of all the nitrate in the drinking water in Canterbury and you will still have people developing colorectal cancer," she said. "There's a whole lot that we need to understand about the different pathways that are involved."
Photo: Cosmo Kentish-Barnes
Professor Jacqui Keenan from the Department of Surgery at Otago University & Warwick Cato from Ballance Agri-Nutrients Photo: Supplied
Tom Lambie, a former commissioner for Environment Canterbury, was in the audience. He said the forum was highly engaging, but stressed the need to balance environmental improvements with financial well-being.
"I'm a practising dairy farmer and nitrates and environmental improvement are extremely important but also we've got to remain productive.
"We need to make sure that we're doing our catchment work and making individual farming decisions that look for best value for money to make the best outcomes."
Speaking from a fertiliser industry perspective was Warwick Cato, the science strategy manager at farmer-owned cooperative Ballance Agri-Nutrients.
His perspective around nitrogen fertiliser and whether it's a friend or a foe was clear.
"My conclusion is nitrogen is not a friend or a foe. It's the man or the humans that use it and so the focus should be on practices and the people component, because that's what really determines the context in which you see nitrogen."
Photo: Cosmo Kentish-Barnes
Learn more:
- Learn more about the conference here
