A recent research paper by Dr Sofia Biffa (co-authors Pippa J. Chapman, Richard P. Grayson & Guy Ziv) has brought to light the potential of hedgerows to sequester soil carbon within agricultural landscapes. Quantifying the amount of CO2 emissions hedgerows could potentially sequester is crucial in the fight against climate change. The study conducted is the first to quantify the soil organic carbon (SOC) sequestration rate associated with hedgerows. The study took place in Cumbria on five dairy farms, where twenty-six hedgerows were chosen based on their time of planting.

Soil measurements were taken from the hedgerows and adjacent fields. SOC was on average 31.3% higher under hedgerows than in the adjacent fields!

The age of the hedgerow played a role in the amount of carbon sequestered:

  • 3.3% for 2–4-year-old
  • 14.4% for 10-year-old
  • 45.2% for 37-year-old
  • 57.2% for older ones

The rate of SOC sequestration was found to be 1.48 Mg Carbon (per hectare, per year) beneath the 37-year-old hedgerow. The Climate Change Committee wants to see a 40% increase in hedgerow length to meet the Net-Zero Targets. Authors found that if England reaches its goal, over 40 years, hedgerows could offset 4.7%–6.4% of present-day agricultural CO2 emissions.

There needs to be more investment from the government, as the current rate of planting funded by agri-environment schemes is too slow, which could be attributed to the low payment rates for hedgerow creation and restoration in current schemes.

Hedgerows are already undervalued landscape features and habitats, highlighting the carbon sequestration potential of hedgerows may increase their conservation and general perceptions of hedgerows.

As agri-environmental schemes move into ELMs the agricultural community may see more emphasis on carbon and may even see payments for carbon sequestration. Making hedgerow conservation and restoration a priority, with benefits for the agricultural sector, nature and the planet.

The full paper can be found here...