Changes to farm payment systems and satisfying supply chain company requirements may require a closer look at carbon balance in the future. We talked to one carbon neutral farmer and two consultants about how they are developing carbon auditing systems.
With businesses in the supply chain now being challenged to deliver carbon net zero, farmers have a role in helping them do this, says Steve Cann, director of Future Food Solutions and founder of Sustainable Futures.
“Brands are keen to reduce their carbon footprint and set benchmarks to become carbon net zero within a certain time frame.
“They can be innovative around electric vehicles, green energy and recycling, but they do not have direct control of carbon in the agricultural supply chain. There is an opportunity to buy into the front end [farming end] with respect to carbon.”
Graham Potter, who farms near Thirsk, North Yorkshire, is one of four farmers selected by Sustainable Futures to help develop carbon auditing.
He says: “Given we are losing the Basic Payment Scheme and the Government is having to reform what we do and how we are paid, there could be benefits if we can prove we are farming carbon neutrally here.
“If we can sell carbon credits, this would be another income stream.”
The fact Mr Potter has good farm records on Gatekeeper has helped him develop the carbon audit.
Mr Cann says: “We wanted to find out the scale of the carbon issue, set benchmark values and understand how we can influence things at farm level.
“We wanted to look at cropping, the farm and rotation, and put together core information about where carbon is generated and how we can manage this.
“The numbers help us identify where the problems are and what the quick wins are, which could simply be choosing a different type of nitrogen. Then we can look at everything else we may have to do to meet the requirements of the new Agriculture Bill, or the needs of the supply chain.
“We can take a hectare of arable land and convert it to woodland, which captures carbon but will not feed anyone. Graham is showing us it is possible to catch carbon and produce food, by looking at the soil side of things as well as carbon emissions associated with diesel use, fertiliser and ag chem.”
For the carbon audit research, Mr Potter sends digital crop records to independent soil scientist Neil Fuller.
He says: “We analyse the data using IPCC [Intergovernmental Panel on Climate Change] values for carbon, our own field data and information from suppliers, for example carbon certificates from Yara for each of their products.
“The results show us carbon management is more about optimising inputs than simply reducing them. Using less nitrogen and crop protection products may reduce carbon emissions per hectare, but if yield is compromised, carbon emissions per tonne can increase significantly, which affects the entire supply chain.”
Mr Cann says Sustainable Futures has developed a workable system which can generate the necessary numbers and is now taking steps to gain accreditation, so industry partners can incorporate carbon audits into their farm record systems.
“We can fine tune it. We need to make it as quick and easy to use as possible. Results need to be meaningful, valuable and informative.”
Nitrogen fertiliser makes the biggest carbon contribution to arable crop production, says Mr Fuller.
“About half of this relates to nitrous oxide released from the soil after fertiliser has been applied.”
Almost 50% of the total carbon reserve in UK arable soils has been lost in the last 60 years.
Sustainable Futures takes a soil-focused approach to practical carbon management.
When Graham Potter began making changes to his farming system, carbon was not being measured.
He says: “Nine years ago, we were not chopping straw or growing cover crops, but we were ploughing and using lots of diesel. We decided to make the change to precision agriculture and seven years ago started direct drilling. Five or six years ago we started growing cover crops and for the second time around, we have cover cropped everything, even between first and second wheats.”
Soil organic matter has improved by 3-4% over the last six years, a gain of fivr to six tonnes per hectare of carbon a year.
“Straw chopping helped a lot and cover crops boosted it even more,” says Mr Potter.
He only uses fertiliser where it is needed, using the N-Sensor, N-Tester and a drone to monitor crops and variably apply Omex liquid, 24% N and 7.5% S.
Mr Potter says he has seen yield benefits following his conversion to a different system.
“When we started with the Claydon system we saw yield increase in the first year, then it dropped off over three years. Now it has started to rise again. In the last three years it has gone up and up. Last year wheat averaged 12t/ha with some doing 14.5t/ha.”
Also, despite the wet autumn and winter in 2019/2020, surface waterlogging is rare and Mr Potter was able to drill most of his winter wheat.
“The soil is like a sponge – it can absorb more water and hold it without losing structure.”
Mr Fuller says Mr Potter’s cover cropping in 2019 produced 30-40t/ha above ground biomass over 10 weeks.
“That’s a carbon input of 3-4t/ha, but less than 1t/ha is needed for Graham to declare he is carbon neutral. It’s everything else Graham is doing that makes this achievable.”
Graham Potter, W. Potter and Sons, Thirsk, North Yorkshire
200 hectares arable
Siletina oil radish 5kg
Berseem clover 1.25kg
Winter oats 9.75kg