Significant Boost for Nitrification Inhibitor Research Announced

5 August 2009

A new partnership between the Ministry of Agriculture and Forestry (MAF), the dairy and fertiliser industries is making a significant investment in researching nitrification inhibitors, new technology that supports farmers to reduce the environmental impact of their farming operations.

MAF and Fonterra today announced a three-year research agreement with DairyNZ, Ballance Agri-Nutrients, Ravensdown Fertiliser Cooperative, New Zealand Fertiliser Manufacturers' Research Association and the Pastoral Greenhouse Gas Research Consortium (PGgRc).

The partners are investing up to $10 million in a research programme aimed at measuring the effectiveness of nitrification inhibitors in reducing nitrous oxide emissions and nitrate leaching while enhancing pasture growth.

MAF Director, Natural Resources Policy, Mike Jebson says previous research conducted by the fertiliser industry has already highlighted the ability of nitrification inhibitors to enhance pasture growth while reducing emissions and nitrate leaching.

"The aim of the new research programme is to improve our understanding of the effectiveness and performance variations which may occur between farms and across regions, due to physical and climatic conditions," he says.

MAF will provide 50 per cent of the required funding with the other 50 per cent coming from Fonterra, DairyNZ and the fertiliser industry. PGgRC will manage the research programme.

Fonterra's Sustainable Production Manager John Hutchings says reducing on-farm greenhouse gas emissions while maintaining global competitiveness is critical for both the agricultural sector and the entire economy.

"By committing to this programme, the dairy industry, fertiliser industry and MAF are taking significant steps toward providing practical tools that support farmers to make positive environmental changes on-farm," he says.

"New technologies such as nitrification inhibitors are key tools for meeting the sustainability challenges the industry faces, including those related to water quality and New Zealand's greenhouse gas emissions from agriculture."

Research will initially involve a series of replicated trials in four dairying regions - Waikato, Manawatu, Canterbury, and Southland. The introduction of two more regions is planned for year two of the programme.

Key variables to be measured include: nitrogen inputs, pasture growth under grazing, nitrous oxide emissions, soil type and temperature, rainfall and drainage.

Media contact:

  • Deborah Gray, Senior Communications Advisor, MAF Policy
    Phone: 64-4-894 0715, Mobile: 029 894 0715, Email:

About the research

1. What are nitrification inhibitors?

Nitrification inhibitors are a new technology that has shown significant promise in reducing nitrous oxide emissions and nitrate leaching, and in enhancing pasture growth in research trials.

Nitrification inhibitors slow down the conversion of ammonium in the soil to nitrate. The ammonium comes from animal urine and nitrogen fertiliser applied to pasture. Once ammonium is converted to nitrate, the nitrate is less strongly held by the soil and can leach into waterways and be converted to the greenhouse gas nitrous oxide, which contributes to global warming.

Nitrification inhibitors slow down this process and are therefore beneficial both to the farmer and the environment, as they:

  • reduce nitrate leaching;
  • reduce the production of the greenhouse gas nitrous oxide, and
  • have the added benefit of improving pasture growth in spring by retaining more available nitrogen in the soil, for grass growth.

2. What form will the research programme take?

The three-year programme will include a comprehensive set of research trials, including the use of controls. In year one, there will be a series of replicated mowing and grazing trials in four dairying regions - Waikato, Manawatu, Canterbury and Southland.

In year two, the intention is to expand the trial to another two regions.

Measurements of key variables over the three years will include:

  • nitrogen inputs,
  • nitrate leaching,
  • nitrous oxide emissions,
  • pasture growth,
  • soil type and temperature,
  • rainfall, and
  • inhibitor effects on cattle dung greenhouse gas emissions.

3. What will the outputs of the research be?

Desired outcomes include:

  • The development of a standard approach for the evaluation of nitrification inhibitors in New Zealand grazing systems.
  • The ability to position the dairy sector to better meet a broader range of sustainability challenges including those related to water quality.
  • Achieving accelerated nitrous oxide emissions reductions
  • The delivery of key information requirements to support farmer uptake.

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