Farming with trees across arable and grassland is key to the farming sector achieving net zero, new research shows.
A new report from the Woodland Trust shows how a major increase in agroforestry – farming with trees – in England, is essential if the country is to meet nature and climate targets, whilst at the same time securing long term food production.
The report draws on new analysis commissioned from Cranfield University and reveals arable farms which adopt silvoarable systems (integrating trees into arable farming which is one type of agroforestry) could lock up eight tonnes of CO2 per hectare per year over 30 years – eight tonnes of CO2 is equivalent to the annual emissions of an UK citizen.
It explains that agriculture is responsible for 10 per cent of UK territorial greenhouse gas emissions with the net effect of “land use, land use change and forestry” responsible for another one per cent. Establishing agroforestry on 10 per cent of arable land and 30 per cent of grassland could enable agriculture-related emissions to reach net zero by 2050 whilst maintaining high levels of food production. Integrating trees into farming systems will enable farms to become more resilient both economically as well as environmentally.
The report also shows that agroforestry would help address the biodiversity crisis by increasing the abundance and richness of farmland species, and birds and invertebrates in particular. It is estimated that the total number of breeding birds in the UK fell by 44 million between 1967 and 2009, and many once-common farmland birds are continuing to decline (references below).
Agroforestry is not only good for supporting wildlife but enhances soil health by improving soil structure and microbial diversity. It may also lead to passive benefits in other ecosystems services such as pollination, pest control, nutrient cycling and decomposition, all of which are essential for long-term sustainable food production.
The report, a culmination of ten months’ work, is timely given the Government is anticipated to outline its plans for the future of farming and land management policy on November 7. Speculation has arisen in recent weeks on the future of its post-EU policy, Environmental Land Management Scheme (ELMS), which is designed to pay farmers and landowners for public goods such as carbon mitigation and habitat restoration. This is essential as it provides the payments and support needed to implement agroforestry and support long term investment and wide scale implementation.
Scientists, a former environment minister, and environmental charities have voiced alarm at any plans to abandon or dilute support for farmers helping nature.
The report shows data which provides evidence for the necessity for the widescale uptake of agroforestry.
Key findings include:
Over 30 years arable farms which adopt agroforestry could lock up, on average, eight tonnes of CO2 per hectare per year – equivalent to the average annual carbon footprint of a UK citizen. This contrasts with typical emissions from arable land, of nearly two tonnes of carbon dioxide equivalent per hectare per year. Establishing agroforestry on 10% of the UK arable area over 30 years (i.e. 484,000 ha; 16,000 ha per year), and assuming a halving of arable GHG emissions per hectare, would enable the arable sector to reach net zero by 2050.
Meanwhile silvopastoral agroforestry can sequester the equivalent of sixteen tonnes of CO2 per hectare per year over 40 years compared to a mean emission for UK grassland with livestock of about four tonnes of carbon dioxide equivalent per hectare per year. Establishing agroforestry on 30% of UK grassland over 40 years (i.e. 3.35 million hectares; 84,000 ha per year), and assuming no other changes, would enable the livestock sector to reach net zero by 2050.
Allowing existing hedges to increase in height from two to three metres can store an additional seven tonnes of carbon per hectare.
Abi Bunker, Director of Conservation and External Affairs at the Woodland Trust said:
”This new research shows just how much good that having many more trees within our farmed landscapes could bring, not just in terms of making important contribution to tackling climate change and helping reverse biodiversity declines, but also in supporting farm businesses to adapt to climate change and become more resilient to the types of financial, social and environmental shocks that are likely to be a part of the future.
“This is about making trees work for farm businesses and the local environment that they operate within and rely on. As a land use it will make farms more resilient both economically as well as environmentally – maintaining food production while providing public goods that are not supplied by many intensive farming systems. It is a sign of hope that there are solutions to grasp – if we take them.
“We urge the Government to commit to ELM with schemes that reflect the long-term investment required to establish and manage trees and set a series of new targets. This report shows how upping agroforestry can help the country meet our climate targets, while maintaining effective farming production.”
