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Farmers to be recognised for sequestering carbon – Expert Reaction

The Government has today announced plans to work with the primary sector on developing a carbon sequestration strategy.

The Government is committed to sequestration being recognised from 2025. Transitional arrangements in place from 2025 with entry into the Emissions Trading Scheme will follow later. Climate Change Minister James Shaw said there is still more technical work to be done.

The SMC asked experts what we still need to learn about on-farm sequestration. 

Professor Dr Sebastian Leuzinger, Department of Environmental Science, School of Science, Auckland University of Technology, comments: 

What technical questions need to be answered before this can move forward?

“In terms of re- and afforestation, most of the tools are there, and while the methods to assess Carbon sequestration, particularly in the soil, are still improving, they have not been the bottleneck holding back the inclusion of Carbon sequestration processes into the ETS. Tree growth is reasonably easily measurable, but tracking Carbon sources and sinks following other agricultural practices is harder and will require more research.”

What kinds of vegetation in what places should a strategy like this incentivise?

“In terms of rapid Carbon sequestration, exotics are better (faster) than natives, but we need a combination of both, in order to achieve other goals, e.g. biodiversity targets. A promising method is to establish pine stands but manage those so that a rapid transition to native forests can happen. The government’s decision will also incentivise roadside and berm plantings. The solution to the climate crisis is incremental, there is no single solution that will rescue mankind. Planting trees in areas that are not otherwise used will buy us time and this is critical. The ‘right tree in the right place’ research is pretty well developed, and sometimes this means exotic trees if the palette of natives is exhausted, particularly where biodiversity considerations may be secondary.”

What forms of emissions removal that also enhance biodiversity could be included?

“Apart from the protection of remnant native forests, reforestation with natives. This is expensive and Carbon sequestration rates are much slower, but we can and should afford this in strategically meaningful places, e.g. to create biodiversity corridors. Protecting wetlands from draining might be another easy and highly efficient way, one that also protects and fosters biodiversity.

“Overall, the government’s announcement is a step in the right direction. Only an evidence-based ETS that includes all measurable Carbon sinks and sources is fair and makes sense. The artificial exclusion of certain industries/locations/processes interferes with the idea of a free and self-adjusting carbon market and is thus not desirable. The ultimate solution will come from both Carbon sequestration efforts and the prevention of Carbon emissions. This is what the idea of a functioning ETS is. There is no reason to exclude any scientifically understood Carbon sink/source processes, other than the powerful lobbying by the private sector.”

No conflict of interest declared

Dr Lucy Stewart, Senior Scientist, Toha Foundry, comments:

“The move towards a more dynamic ETS that can recognise a broader category of sequestration activities is welcome. The focus on forestry has been detrimental both to the environment and rural communities. The ETS needs to move with the science to avoid these perverse outcomes.

“Allowing on-farm sequestration will also allow for greater dynamism in land-use. Farms that under current settings would be retired for plantation pine once agricultural emissions pricing is introduced may be able to diversify land-use to take advantage of sequestration opportunities. This will have many environmental and social co-benefits.

“The science community will need to get in behind this work to help farmers adopt credible approaches to sequestration that can deliver these co-benefits.”

Conflicts of interest statement: Toha is working with researchers and landowners to reliably measure and prove regenerative environmental outcomes, including methods of carbon sequestration currently sitting outside the ETS. 

Honorary Professor Troy Baisden, Motu Affiliate, Te Pūnaha Matatini Principal Investigator, and University of Auckland School of Environment, comments:

“Today, the government has made three press releases related to agriculture, forestry and climate change mitigation. The most interesting announces a plan to enable farms to claim credit for carbon sequestration under the Emissions Trading Scheme (ETS). The announcement means that from 2025–2030, 100% credit will be given to carbon sequestration, in contrast to the only 5% charging for emissions of nitrous oxide and methane emissions from farms.

“It is important to acknowledge that commitment represents a path forward on an issue where trust has eroded between the government and the farming industry representatives who contributed to the He Wake Eke Noa process. Transitions toward incorporating emissions reductions in the economy will require trust between the farming industry and government and in the science.

“The path forward acknowledges that it is scientifically possible to measure and give credit for carbon sequestration on farms. The problem is that the costs of measurement may exceed the value of the carbon sequestered. If the problem is solved, that will happen through improving methods and technology. It may also help farmers fund their pathway forward under climate change regulations.

“But earlier this year, the Climate Change Commission (CCC) evaluated whether it had confidence of getting methods in place by 2025 when agricultural emissions begin to enter the ETS. The CCC wasn’t confident that robust methods could be in place farm-scale carbon sequestration by 2025. Today’s announcement allows for arrangements that are still transitional in 2025.

“The process of getting high-quality scientific methods in place through transitional and final arrangements will be important because of the high level of scrutiny on emissions reductions that are bought and sold, particularly in national ETS. Decades of research have developed trustworthy methods that work at larger scales, such as large forest estates and give confidence in New Zealand’s international reporting and ETS. The Parliamentary Commissioner for the Environment has recently used the reporting of emissions as one of the few examples of research investment yielding clear outcomes. It can be contrasted with the much lower confidence in accounting for whether nitrogen and phosphorus losses from farms can be matched to catchment scale water quality outcomes.

“Today’s high carbon prices ($86 per tCO2e today) and further rises may spur some technology development. Some may result from new technology, such as satellite remote sensing, or bringing the LIDAR sensors mounted on drones to bear on measuring small forests and plantings. These sensors have advanced rapidly, recognising faces on iPhones, and contributing to progress on self-driving cars. Other advances may depend on models, which are increasingly used in voluntary carbon markets but aren’t trusted unless verified with measurements. Restoring wetlands is an important opportunity that lacks well developed methods applicable across the entire country.

“There will also be at least a few vexing science issues to work through at pace. For example, converting eroding pasture land to forest certainly represents a carbon sink in the trees. But it can turn off sequestration due to burial or eroded soil carbon in valleys, wetlands or coastal estuaries, matched with ongoing replacement of soil carbon in the pastoral upland. The erosion-deposition accounting issue has been recognised for over two decades and there remain a lack of methods to account for the problem at the farm scale. Some of the science will still be challenging in 2025.”

Conflicts of interest statement: I have some work related to developing methods for agricultural emissions accounting.

NOTE: The Office of the Prime Minister has issued a correction to its announcement, where it previously incorrectly said sequestration will be in the ETS starting from 2025. The corrected announcement says, “Government is committed to sequestration being recognised from 2025” and “Transitional arrangements in place from 2025 with entry into the ETS to follow later. The comments collated by the SMC were written in response to the initial media release, which has resulted in some inconsistency between the expert commentary and the corrected release.