Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

Greenhouse gases

Output 3: Improved measurement and mitigation of greenhouse gas emissions from the terrestrial biosphere


New Zealand must meet its international greenhouse gas reporting obligations and decrease net emissions of greenhouse gases from terrestrial systems to below ‘business as usual’ levels. To achieve this, it is necessary to have (1) a robust inventory of net emissions and carbon storage and (2) effective mitigation options for reducing net emissions. Changes in emissions and carbon storage as a consequence of management, land use and global change can then be forecasted and appraised. New Zealand is required to produce an annual inventory of greenhouse gas emissions under the UNFCCC (United Nations Framework Convention on Climate Change).

While there has been a lot of research effort to estimate changes in above-ground carbon storage in vegetation with land-use management, much less is known about the effects on soil carbon storage. Although New Zealand’s commitment to reduce net greenhouse gas emissions does not include changes in soil carbon storage, we are required to report such changes annually in relation to land management and land-use change.

Research is needed to develop new methodology for measuring soil carbon storage and for reducing uncertainty for estimating and scaling emissions, and quantifying changes in emissions as a consequence of key land-use and management change. This will allow mitigation strategies to be developed and approaches for increasing carbon storage to be identified and adopted. This is an area in which the science challenges are substantial and we are developing new national and international collaborations to address them. We have a significant role to play and are acknowledged internationally for our expertise in carbon and nitrous oxide science.

Impact 1 : Terrestrial greenhouse gas emissions and removals are understood and quantified so that changes in relation to management strategies, land-use policies and global change can be predicted.



MPI and MfE are using verified estimates of greenhouse gas emissions and carbon storage to reduce uncertainty in national inventories.
  • Afforestation was greater than deforestation (579 000 ha ± 2% and 75 000 ha ± 6% respectively) in New Zealand between 1990 and 2008. The difference gave MPI an estimate of carbon emissions due to forest changes
  • Modelling the growth of pine forest and kanuka/manuka stands is providing MPI with carbon sequestration rates and data on how these vary regionally and temporally
  • The uncertainty in estimating soil carbon for perennial croplands in MfE’s Soil Carbon Monitoring System has been significantly reduced

Impact 2 : Strategies for land use and asset management increase carbon storage, mitigate greenhouse gas emissions and balance environmental, economic and social benefits.



Agricultural land managers and DOC are, where appropriate, using validated methodologies and land-use practices to mitigate greenhouse gas emissions and increase carbon storage and adapt to likely climate change effects.
  • The effectiveness of the nitrification inhibitor DCD in reducing nitrous oxide emissions from stock effluent can now be optimised for use by agricultural land managers
  • Land managers have an improved basis for incorporating variability in carbon stocks when planning emissions management for natural forests