The 1,040ha CAFRE hill farm at Glenwherry in Co Antrim currently has significantly higher carbon emissions than the lowland dairy or beef and sheep farms based at Greenmount campus, CAFRE technologist Aleathea Brown has confirmed.
Shown in Table 1 are the total emissions expressed as tonnes of carbon dioxide equivalent (t CO2e) to allow for the fact that the three main greenhouse gases related to agriculture (CO2, nitrous oxide and methane) all have different warming effects.
While the hill farm does have the most livestock, with 100 suckler cows and 1,100 ewes, when spread across 1,040ha it has a very low stocking rate.
The dairy farm at Greenmount covers 190ha, of which 50ha is cropped annually. Itsupports 180 cows plus followers.
The beef and sheep centre at Greenmount has 90 sucklers plus finishing cattle, and 110 ewes on 120ha.
The data in Table 1 were produced using a carbon calculator developed by Scotland’s Rural College (SRUC), and also include estimates of the carbon taken in by hedges, trees and the soil.
“The biggest surprise for us was the fact that our Hill Farm was actually emitting a lot more greenhouse gases than we thought. We had 1,000ha of land that we thought was sequestering carbon. In fact, some of the peatland is in degraded condition and is releasing greenhouse gas,” said Brown.
She explained that work has begun to reduce the additional 3,072t coming from land use at the hill farm, by restoring/rewetting peatland so that it will sequester rather than emit carbon in the future.
Across all the CAFRE farms, a range of technologies are being used to reduce carbon emissions said Brown, to include planting hedges and trees, use of legumes such as clover, lowering age at slaughter, improving silage quality and use of homegrown feeds.
However, she acknowledged that not all these technologies will be accounted for in the various carbon calculators now available to farmers.
“None of them cover every area of the farm, including sequestration. There is still a long way to go,” she said, adding that the SRUC Agrecalc version is “the best one out there currently”.
Agrecalc has also been used by the seven farmers participating in the ARC Zero project.
One of the main issues is gathering together all the information to calculate a carbon footprint in the first year. “It needs to be more streamlined. At the minute, there are a lot of farmers that would not take it on. It is onerous,” suggested ARC Zero participant John Egerton.
The initial findings from a European Innovation Partnership (EIP) project involving seven farms across NI indicates that there is significant potential to sequester and store more carbon in soils.
Explaining the concept behind the ARC Zero initiative at last Wednesday’s climate change conference, project leader Dr John Gilliland said the aim was to produce an accurate whole-farm carbon balance sheet by measuring all on-farm carbon stocks.
“We have a lot of knowledge around GHG emissions. We have very little knowledge around carbon sequestration,” he told attendees.
As well as undertaking carbon benchmarking using the SRUC Agrecalc tool, each farm has measured soil carbon in 2ha blocks, and also participated in a LiDAR survey to assess the amount of hedges and trees, and the overland flow of water to sheughs and rivers, etc.
During his presentation, Gilliland highlighted two main findings from soil data obtained from the farm of Ian McClelland outside Banbridge. A 60ha farm, milking 88 cows, most of the land is in grass, with a small area of trees.
The first point is that while all fields on the farm receive slurry, those fields regularly grazed by cattle generally have more carbon than those cut and grazed, which in turn have more carbon than fields continually cut for silage.
The second main finding is that across the McClelland farm, soil type is consistent, yet the work has found a range in carbon stocks from 96t/ha to 193t/ha.
The highest carbon stocks were found in an area of deciduous woodland.
“If he wanted to change his management practices, and if the right policies were there, and he was rewarded for it, he [Ian McClelland] could hold 11,500t which is roughly 5,000t more than he holds today,” suggested Gilliland.
The Ulster Farmers’ Union (UFU) is opposed to a forced reduction in livestock numbers in NI as part of a policy to meet climate change targets, the organisation’s president Victor Chestnutt has said.
In concluding remarks at the UFU/DAERA climate change event, Chestnutt maintained that removing the ability of local farmers to produce high-quality food would be irresponsible at a time when global demand for food is rising.
He said that the UFU wanted to see climate change legislation in NI by next spring, ahead of a Stormont election, but that it “must be the right legislation”. He hit out at the private member’s climate bill which would set a target for NI to have net zero emissions by 2045, describing it as “completely unacceptable”. The alternative DAERA-led bill, which includes a target to reduce emissions by at least 82% by 2050, “is not perfect either, but it has evidence behind it,” he said.
Chestnutt was also critical of the UK government around recently announced trade deals with Australia and New Zealand.
A member of the UK Trade and Agriculture Commission (TAC), the body set up to advise on trade policy, Chestnutt said that he and others had put a lot of work into producing a report to government in March 2021.
“It was a balanced and compromise report. Eight months later, government has come back with a few warm words, while in the meantime they have forged ahead in doing the very opposite of what was in that report. That will not cut it. I feel used and abused,” said Chestnutt.