Net-Zero Agriculture: How Regenerative Farming Practices are Leading the Way

By Dr Dawn Teverson, Technical Manager, LEAF, UK

The agriculture sector in the UK contributes 10% of total greenhouse gas emissions, which means that it has a crucial part to play in the race to net zero. Farmers are in the unique position that they own and manage 70% of the land in the UK and, therefore, can make a huge difference. Many of these changes towards net zero involve adopting regenerative practices and the mindset of Integrated Farm Management. Regenerative agriculture focuses on building soil health, increasing biodiversity, and reducing carbon emissions. By implementing regenerative practices such as cover cropping, reduced tillage, and rotational grazing, farmers can sequester carbon in the soil, promote healthy ecosystems, and reduce their overall carbon footprint. This makes regenerative agriculture a key component in the fight against climate change and achieving net-zero emissions.

Looking into the increasing range of possibilities for reducing greenhouse gas (GHG) emissions at an individual farm level is the first step towards net zero. Using a carbon benchmarking tool to understand GHG emissions and identify areas for improvement is the start of the journey. Soil carbon is the basis of healthy and productive soils, critical for food production and sustaining all biodiversity and landscapes. Soil carbon sequestration is the process by which CO2 is removed from the atmosphere and stored in the soil carbon pool. This process is primarily mediated by plants through photosynthesis, with carbon stored in the form of soil organic matter (Lal 2008).

Improving soil health is central to Regenerative farming, and other net zero benefits follow as a result. So, what does this improvement look like? One of the obvious advantages is higher levels of soil organic matter, resulting in improved water retention and, thus, greater resilience to extremes in weather that are likely to be caused by climate change. Anyone who needs to be convinced of this only needs to ask a farmer who has had to deal with the recent droughts. Andy Neal at Rothamsted Research states that for a silty-clay loam, ‘every 1% increase in soil organic carbon equates to a water holding capacity increase of 354,000 litres a hectare to a depth of 30cm’. Increases in soil organic matter improve yields, soil workability and therefore reduced cultivations, resulting in reduced diesel usage and a reduction in both input costs and carbon footprint. And it’s not just anecdotal evidence, Rothamsted Research has been conducting long-term experiments since 1843 on the effect of soil, crop, manuring, and management on changes in organic matter under temperate climatic conditions.

Production of artificial fertilisers is an energy-intensive process, on its own, estimated to be responsible for almost 1.5% of total global emissions. So, reducing additions of these fertilisers whilst maintaining soil fertility is a key step towards achieving net zero. Soil organic matter helps to retain the valuable nutrients in the soil that are critical to crop growth. By measuring the residual nutrients in the soil and applying the right amount of additional fertiliser, matched to the needs of the crop being grown, expensive inputs aren’t wasted. Once applied, nutrient loss needs to be minimised. Not only are they expensive, but once they’ve entered the watercourse, nutrients are a pollutant and can severely reduce biodiversity. Using fertiliser efficiently is a win-win outcome for both farmers and the planet.

Keeping the soil covered – the second principle of Regenerative Agriculture – protects the soil from erosion caused by heavy rain, thus minimising the loss of dissolved nutrients into the nearest watercourse. Many species are suitable for cover crops, and selection will depend on the farming system and objectives. Legumes such as clovers and beans leave residual nitrogen, which benefits the following crop and improves soil fertility through their symbiotic association with rhizobia, which fixes atmospheric nitrogen. This reduces the need for artificial nitrogen fertiliser in the following crop, thus lowering greenhouse emissions.

Including livestock in arable rotations provides a range of benefits to the soil. The addition of nutrients is the obvious one, but others include improvements in soil structure and plant and microbial diversity, leading to overall improvements in soil biology. Cover crops can be destroyed by grazing before the following cash crop and lush growth of autumn cereals are controlled. Combining several regenerative principles whilst simultaneously reducing the need for artificial fertilisers, which are expensive both in terms of cash and carbon cost, is the increasingly popular practice of using multi-species swards for feeding cattle and sheep. As with cover crops, the mixture of rooting structures provides nitrogen-fixing by legumes and improves soil structure from deeply rooted species. Increased water retention is also advantageous in drought conditions when forage availability is crucial. Some species of herbs even have the potential for parasite control in grazing animals, thus reducing the need for wormers, another step towards self-sufficiency and net zero.

By adopting regenerative practices, farmers can reduce their carbon footprint, improve soil health, and enhance the resilience of their farms in the face of climate change. Opportunities for such learning are becoming increasingly available as regenerative practices are shown working in the field. Our goal within AgriCaptureCO2 is to help them on that journey.