Ground-penetrating radar to map peatland subsurface and the impacts of forest-to-bog restoration

Despite the global surge in efforts to restore afforested and drained peatlands, forest-to-bog restoration remains poorly understood and rarely evidenced. In this study we employ Ground-Penetrating Radar (GPR) to survey the subsurface of peatlands in three different condition states: near-intact, afforested, and restored. Exploring the capabilities of GPR applications in peatland settings beyond basic peat depth surveying, data obtained using 250MHz antennae show the penetration depth of tree roots at the afforested site. In addition, patterns of subsurface reflections gained using higher frequency (500MHz) antennae were compared between sites to interpret the impacts of forestry and subsequent restoration interventions. Through a trial-and-error process of obtaining and processing the data, our research contributes to the emerging field of ‘agrogeophysics’ by addressing the challenges associated with surveying manipulated and afforested peatland environments. The outputs of this study offer insights into degree and spatial variability of subsurface degradation and the effectiveness of restoration, helping to inform operational best-practice and policy of peatland restoration. Ongoing research will ground-truth findings by integrating direct hydrogeophysical measurements and develop a quantitative index to identify and interpret different reflection patterns.