Supporting farmers to reduce greenhouse gas emissions

Supporting farmers to reduce greenhouse gas emissions

1 April 2021

Nick Tait, DairyNZ Senior Solutions and Development Specialist, on how understanding, managing and reducing greenhouse gas (GHG) emissions will be a significant focus for dairy farming businesses in the coming years.

Recent research commissioned by DairyNZ and undertaken by AgResearch shows New Zealand’s dairy farmers are the world’s lowest emissions producer of dairy products in the world. However, we know that globally, other dairy producers are focused on improving efficiency and reducing their environmental footprint.

To stay ahead of competitors and play our part to reduce emissions, we all need to continue to innovate and adapt practices while maintaining viable businesses. All sectors and New Zealanders will need to play their part to address climate change.

Establishment of partner farms and modelling

To help our farmers along this journey, we established 12 partnership dairy farms as part of the Dairy Action for Climate Change in 2017.

The Dairy Action for Climate Change is a commitment to support dairy farmers and the wider sector to address on-farm methane and nitrogen (N) emissions long-term.

Modelling work was carried out on the 12 partnership farms, which cover a range of farm systems across New Zealand. The aim of the work was to identify options for farmers to reduce GHG emissions and N leaching. The modelling work included looking at how these options would affect farm profitability and productivity.

Mitigation options

Three categories of mitigation options were modelled: farm management changes to the current farm system, infrastructure investment and changes, and retiring lower productive areas of the farm and planting in trees.

The reductions in methane generally came from reducing dry matter (DM) intake per hectare (ha), as this is the driver of methane in OverseerFM. Reduction in nitrous oxide emissions mainly came from reducing N surplus, such as reducing N fertiliser and feed inputs.

Learnings from the project

The project identified key learnings about reducing environmental footprint while documenting the effect on profitability and productivity. The key learnings include:

  1. The importance of understanding your farm system and goals at the start, as well as involving the farm’s key rural professionals to support the process.
  2. The importance of good data for modelling farm system options that will reduce both N loss from the root zone and GHG emissions. Good information is required to represent the farm system accuracy.
  3. The opportunities that are currently available on some farms to improve both profit and reduce emissions through good management practices. However, there is no ‘one-size-fits-all’ package of mitigations that every farmer can implement. Mitigations need to be farm-specific, as some may not be relevant or do not align with the specific farm’s goals.
  4. The relationship between reducing N loss and nitrous oxide emissions. To reduce both, there needs to be a focus on reducing N surplus. Currently, options to reduce methane are limited to reducing the farm’s total DM intake.
  5. Options for some farms that offer lower footprint and high profit. For already efficient farms, footprint gains tended to come at a cost to profitability. This confirms that mitigation options need to be farm-specific. The farm’s starting position will also determine the magnitude of any reductions.

The future

DairyNZ will continue to work closely with the farmers involved in the partnership farms to identify how successful any options implemented have been. The work will also identify further opportunities to reduce environmental footprint while maintaining or increasing profit.

DairyNZ’s Step Change programme is helping dairy farmers understand their GHG emissions footprint and how to reduce emissions while contributing to better water quality and improving profitability. The project is designed to help farmers understand the options best suited to their farm.

Farmers interested in learning more about improving their environmental performance and profitability can find out more at dairynz.co.nz/stepchange

Information on the partnership farms is also available on the DairyNZ website, which includes case studies on six of the partnership farms. The case studies outline options for farms to reduce both N loss and greenhouse gas emissions and looks at the effect on profitability.

dairynz.co.nz/GHGfarms

Article supplied by Dairy NZ.