Restoring peatlands for carbon storage – when will we see results?

The upland peatlands of the UK have been severely eroded because of industrial pollution, overgrazing, drainage and other human actions. Research from The University of Manchester is helping to understand how they can be restored to assist the fight against climate change, and how long it will take to see results.

In collaboration with Moors for the Future Partnership who are restoring blanket peat in the South Pennines, Manchester researchers collected a large-scale dataset over a ten-year period, allowing them to study the rate of change in the peatland ecosystem after their restoration.

Controlling the peatland carbon balance

The team looked at the key ecosystem responses to restoration including: vegetation cover, water runoff and water quality. Findings indicated that different functions of the peatland responded at very different rates.

These findings provide invaluable insight into how we can control the peatland carbon balance. They underpin the approach to monitoring peatland restoration success in the Natural England and Department for Environment, Food and Rural Affairs (Defra) Nature for Climate Peatland Grant Scheme, which aims to reduce carbon emissions from peatlands in the UK by nine megatonnes of carbon dioxide equivalent by 2050 — while also delivering co-benefits such as flood risk mitigation and biodiversity gains.

Understanding restoration processes

Peatlands are the world's largest natural terrestrial carbon store, holding more than 20% of soil carbon. However, in the UK at least 80% of peatlands have been damaged by human activity. Widespread erosion of peatlands means tonnes of CO2 being released into the atmosphere every year, a decline in natural habitats for wildlife, and increased flood risk.

The restoration of peatlands is vital for combatting climate change, and over several decades extensive efforts have been made to revegetate and restore upland peatlands in the UK. During this work, there has been limited understanding of how long it will take to see change; making it difficult to plan timescales for restoration projects, and measure levels of success.

For example, in our research, efforts to revegetate the bare peat worked quickly, reducing both the amount of carbon lost through erosion, and water runoff — helping to reduce flood risk. The return of biodiversity and recovery in water levels were much more gradual throughout the period.

Understanding the restoration processes, and how quickly change takes place, provides an opportunity to develop 'soft-geoengineering' approaches, where interventions are made in natural systems to counteract climate change.

The Manchester team is now working as part of the Biotechnology and Biological Sciences Research Council's Greenhouse Gas Reduction programme, exploring ways to optimise restoration approaches to maximise carbon storage by peatlands.