Increasing the quantity of carbon stored in agricultural soils has the potential to offset emissions of greenhouse gases to the atmosphere, while soil carbon losses would further add to those emissions.
However, realising this mitigation potential is technically challenging when soil carbon stocks are already high (as they are in New Zealand), potential changes in soil carbon are small and spatial variability is high.
The current NZAGRC programme has three distinct components:
(1) testing specific management practices that may increase the long term soil carbon store in field situations;
(2) developing and using models to predict how a range of management practices may influence long and short tem soil carbon storage; and
(3) identifying those factors that influence the stability of current or newly added soil carbon.
We have also supported international work to map on farm soil carbon and will participate in the international research programme CIRCASA.
Dr David Whitehead, Manaaki Whenua - Landcare Research (2010-present)
Professor Frank Kelliher, AgResearch (2010-2017)
Principal Investigator - Dr David Whitehead
Funding Brings Clarity to Soil Carbon Research
NZAGRC funding over the last decade has improved clarity about soil carbon research and provided a structure for building a knowledge base both in New Zealand and the international scientific community, says Dr David Whitehead.
David, of Manaaki Whenua – Landcare Research, is one of four Principal Investigators leading the Plants and GHGs (greenhouse gases) research programme for the NZAGRC.
Asked what the research programme has delivered since the NZAGRC began its work, David points to the progress made in science knowledge. "It has provided the opportunity to start new programmes and approaches and we have gained so much knowledge about carbon stocks in New Zealand soils and how they are changing in relation to management.”
David’s role has been to review progress, identify and prioritise research gaps and co-ordinate integrated research programmes.
After specialising in science at school he went to the University of York to study biology then did his PhD at the UK Government organisation Rothamsted Research and his Post Doc research at the University of Edinburgh where his perspectives were transformed by working on water use by Scotland’s forests.
David’s training in carbon uptake and water use led him to explore management options to increase productivity when he began working at the New Zealand Forest Research Institute (now Scion) in Rotorua. The focus developed to improve wood quantity rather than quantity and this in turn led to studying opportunities to increase carbon storage in vegetation and soils to offset greenhouse gas emissions.
David says that in New Zealand, interest is growing in ‘regenerative agriculture’ but much of the evidence for success is anecdotal and lacks scientific credibility. “While I am not suggesting that we revolutionise our agricultural practices, I do feel that we need to be more willing to address opportunities provided by, for example, changes to grazing intensity and frequency, multi-species mixed cropping, soil amendments, etc. There is growing evidence that increasing diversity leads to more sustainable, resilient farming systems.”
Back to News