The NZIAHS forum in Wellington on September 14 addressed agriculture and its place in the Emissions Trading Scheme (ETS) and examined how science can help farmers respond to the challenge of reducing greenhouse gas emissions.
Seventeen speakers dealt with four key themes during the day:
- What political parties are proposing for agriculture;
- The entry of agriculture into the emissions trading scheme;
- Finding agricultural solutions to enable farmers to reduce their greenhouse gas emissions; * Considering how agricultural industries can mitigate emissions.
In his introductory remarks, forum co-chairman Dr Jim Salinger summarised recent modelling studies and noted that many climate change scenarios are based on science from the Intergovernmental Panel on Climate Change 2013 reports five years ago. To reach the Paris Agreement target of keeping global warming less than 2 degrees centigrade will require a reduction of more than 50% in anthropogenic methane emissions.
Agriculture makes up more than 50% of New Zealand’s greenhouse gas profile and meat production makes up 50% of agriculture emissions. This calls for a major change to production and biogenic processes. Methane offsets will be critical to this reduction – it is a short-term warming agent and reductions will rapidly reduce the contribution of agriculture to further warming. Globally given the amount of greenhouse gas emissions from meat production there could well be a trend away from meat protein towards plant based protein diets
Gareth Hughes (Green Party MP).
Mr Hughes noted that 12% of global emissions are sourced from agriculture and this is the sector most at risk from climate change impacts. Mitigations to focus on for farmers include feed choice, standoff pads, decrease stock numbers and decreased nitrogen fertiliser use.
Nathan Guy (National spokesman on agriculture).
National, which endorses a pragmatic, science-based approach to tackling climate change, supports the idea of treating gases differently in the ETS and says the incentives need to drive long-term changes rather than comprise short-term shocks. Mr Guy noted that only 2% of farmers know their emissions. A farm plan to deal with climate change “is probably a good initiative” but it needs to be folded into the several farm plans already in operation.
In his summing up remarks, co-chairman Rod Oram said a political consensus is taking shape, although it’s consensus is at a very high level. As more work is done on the science, policy and practicalities he foresaw “intense debates about keeping that consensus together”.
Entry of agriculture to the Emissions Trading Scheme –
How and when should agriculture enter the ETS
Simon Upton (Parliamentary Commissioner for the Environment).
There is no single best way to bring agriculture into the ETS and before New Zealand can mitigate emissions we need to know more about the biological sources and sinks in New Zealand. With a goal of no additional warming, methane would need to be reduced 10-22%; this means that holding methane levels steady will not be enough to reduce warming.
Methane and nitrous oxide, which are short-lived gases, react differently than carbon dioxide in the atmosphere. Hence there are discussions about whether they should be managed differently in climate-change policy by separating agricultural emissions from fossil emissions.
A key issue is how forestry should be addressed because forests are not permanent and land conversion must be economically viable. If forestry is to be used for mitigation, the sources and sinks should be connected.
Mr Upton is to release a report on Overseer before late December 2018. It will examine (1) whether Overseer is fit for purpose to be used in a regulatory context; (2) how it can be connected to catchment scale models, because currently it considers only flows to the bottom of the root zone; (3) whether the ownership of Overseer is appropriate.
Penny Nelson (deputy director general policy and trade at the Ministry of Primary Industries).
Ms Nelson outlined the ministry’s role in shaping and managing climate change policy-and in giving advice to the government based on evidence for decision making. Within the policy process, there needs to be early consultation with a range of different perspectives.
Dr Phillip Wiles (from the Biological Emissions Reference Group).
BERG’s job is to increase understanding across industry, government and the public regarding current and future drivers of biological emissions and mitigation potentials. The costs of and opportunities for mitigating GHG must be investigated. The group can only advise and not develop policies and recommendations.
BERG has commissioned research on mitigation potentials including once-a-day milking, supplementary feed, a shift from dairy to beef farming, and the impact of small tree lots on farms for mitigating greenhouse gases. Research has also been undertaken to understand what drives farmers’ decision-making in relation to climate change. A report on potential mitigations will be released over the next month or so.
Dr Kennedy Graham (founding director and a trustee of the New Zealand Centre for Global Studies).
Scenario modelling has shown NZ food production can be maintained and net zero emissions achieved by 2050.
Dr Kennedy referenced two reports, from Vivid Economics and the Productivity Commission, both of which concluded that meeting Paris Agreement obligations requires steep reductions in all greenhouse gas emissions: Vivid Economics concluded this calls for a 50% reduction in methane while the Productivity Commission concludes a 25% reduction is needed to achieve Paris targets.
Finding agricultural solutions
How can farmers reduce their greenhouse gas emissions
Mark Aspin (general manager of the Pastoral Greenhouse Gas Research Consortium). –
The consortium’s mission is to provide knowledge and tools to farmers to mitigate greenhouse gases (GHG) for all livestock. Research has focused on four key areas: animal genetics; low GHG feeds; a methane vaccine; and methane inhibitors.
Research has found no pasture-based plants consistently reducing methane, and the methane content does not vary seasonally. Maize silage and palm kernel extract have no methane, but brassicas reduce emissions by up to 30% although their nitrous oxide effects remain to be determined. Fodder beet shows some promise at high diet levels.
New Zealand soils have high levels of carbon compared to other countries. Research is ongoing but there is agreement that while maintaining soil carbon for soil health and production is important, the value of managing carbon for greenhouse gas purposes has yet to be proved.
Dr Robyn Dynes (science impact leader at AgResearch). – Agricultural emissions are 80% methane and 20% nitrous oxide, 46% of them coming from the dairy industry. To mitigate these two gases farmers will need to manage dry matter intake (methane) and nitrogen surplus (nitrous oxide). Dr Dynes outlined work being done at the Lincoln University Dairy Farm, where the low input system reduced nitrogen loss by 25% and greenhouse gases by 20% while maintaining production.
Andrew Hoggard (national vice-president, Federated Farmers
New Zealand farmers are world leaders at producing food (per kg of product) with a low-emission footprint: 1kg of New Zealand beef generates 22kg of carbon dioxide-equivalent whereas the global average is 26.6kg.
To mitigate greenhouse gases farmers need to better understand where they are starting from – only 2% of farmers know their GHG level, 97% underestimate their farm emissions and 42% are unaware of mitigation strategies other than to plant trees. This knowledge is an urgent priority.
How can agricultural industries mitigate emissions
Dr David Burger (DairyNZ strategy and investment leader for Responsible Dairy)
Of the 46% of agricultural emissions from the dairy industry, 85% is sourced from on-farm operations, 10% from processing and 5% from transport. The dairy industry has already made big steps to reduce its emission profile with a 29% decrease in emission intensity through pasture and genetic management.
DairyNZ has established ten greenhouse gas partnership farms to demonstrate the potential reductions in biological emissions through farm system changes and their impacts on production. These mitigations are: improve farmer practices related to effluent and irrigation management; use off-paddock facilities; intensify farming over a long period; on-farm investment in standoff facilities and effluent management; retire land to forestry.
Victoria Lamb (environment policy manager Wellington, Beef+Lamb NZ).
The goal of the sheep and beef sector (which has 27.37 million sheep and 3.61 million cattle) is to become carbon neutral by 2050. Total emissions are already 30% below 1990 levels. Sheep and beef farms have 2.5 million ha of native biodiversity with 1.4 million ha of woody forest type trees. This means 53% of the native forest needed to offset all emissions and 34% of the necessary pine forest is already on farm.
Management changes required to offset emissions are (1) replace breeding cows with dairy-bred animals; (2) alter the sheep/cattle ratio; (3) reduce nitrogen fertiliser use and/or replace it with legumes.
Tools to estimate and mitigate emissions must be integrated with other management systems to provide a holistic approach with other services, such as water quality and biodiversity.
Dr Alison Stewart (chief executive of the Foundation for Arable Research).
The arable sector feeds 6 million dairy cows and 30 million sheep every day. Critical issues are capability development and the right to farm while meeting the challenges of water, soil erosion, greenhouse gas emissions, nitrogen and phosphorus.
Greenhouse gas emissions from wheat production are 32% from field emissions of nitrogen fertiliser and 26% from nitrogen fertiliser manufacturers. Mitigations include the reduction of nitrogen fertiliser use (target of 30-50% reduction); the timing of fertiliser applications; better crop rotations (25-40% uptake of minimum tillage practices); and the reduction of soil compaction.
Richard Palmer (deputy chief executive of Horticulture New Zealand).
Horticulture contributes a small percentage of New Zealand’s greenhouse gases but reductions are still necessary. There is no single solution because the emissions profile varies significantly among different crops. Key innovations are required around breeding and plant-based proteins and adaptation.
Research into the fertiliser needs of crops is ongoing through deploying real-time wireless nitrogen, phosphorous and potassium probes to optimise fertiliser use.
Carolyn Mortland (director social responsibility, Fonterra).
Fonterra’s carbon footprint stems from land use (90%); processing and packaging (9%); and distribution (1%). One third of the company’s plants are still coal-powered but there is a shift to electricity. New Zealand is the world’s most efficient producer of milk due to year-round pasture grazing, high pasture production per hectare, a low cow replacement rate, and a low use of supplementary feed.
Greater diversification of land use will be required to reduce emissions but the economic and social impacts of change need to be understood. Reducing operations emissions by 30% by 2030 to become net zero by 2050 will require technology advances and new funding mechanisms.
Caroline Read (chief executive of Overseer, who was invited to address the forum in response to many references to Overseer during the day).
Overseer recently released new software designed to reach farmers much more easily and increase their engagement in using Overseer to make on-farm changes.
A calibration programme is under way to recalibrate the Overseer engine against farmer information.
Staff have been talking with the Parliamentary Commissioner for the Environment while he prepares his report on Overseer and its usefulness for regulatory purposes.