Evaluating the Impact of Blanket Peatland Restoration on Carbon Dynamics using 3D X-ray Micro-Computed Tomography

Peatlands are the second largest global store of carbon and represent the most efficient terrestrial carbon store on the planet. ~13% of the world’s blanket peatlands are located in the UK, and they play a potentially crucial role in regulating climate. It is estimated that they store ~3.12 billion tonnes and sequester ~5.5 million tonnes of carbon per year, equivalent to ~1% of the UK’s total annual greenhouse gas emissions. However, unsustainable anthropogenic exploitation of blanket peatlands has resulted in ~90% of the known extent in the UK categorised as being in poor condition under the Joint Nature Conservation Committee standards. This is a consequence of these peatlands experiencing cutting, overgrazing, burning, drainage, and erosion. Due to these anthropogenic disturbances, UK blanket peatlands are suggested to emit ~10 million tonnes of carbon per year, representative of ~2% of the UK’s total annual greenhouse gas emissions. In response, the UK Government has incorporated peatlands in national level policy through the setting of restoration targets under climate change commitments. However, restoration targets are not being met and there are no ‘hard’ policies for blanket peatland restoration specifically. This is partly due to a lack of primary research into the effectiveness of peatland restoration.

This study explores the interactions between peat structure and peat function, which is indicative of carbon sequestration and storage (carbon dynamics), in restored blanket peatlands under different treatments and timescales in Cumbria, England. 3D X-ray Micro-Computed Tomography (µCT) is applied to peat core samples from natural, degraded, and restored blanket peatlands to visualise and quantify the internal structure of peat soils at a 0.51µm resolution. Structures include; 1) air filled and water filled pore networks; 2) air filled and water filled root networks; 3) peat matrix density; and 4) other organic matter developments which regulate the carbon dynamic function of peat soils. For the first time, this study will identify and evaluate the impact of blanket peatland restoration on peat structure and function. The investigation is also reinforced with bulk chemical and field monitoring datasets. These are integrated with the µCT outputs to understand the response of carbon dioxide and methane dynamics to blanket peatland restoration.