Efficacy of Peatland Restoration in the North York Moors National Park, UK: A Multi-Year Empirical Study on Drought Resilience and Carbon Sequestration

Abstract

Degraded peatlands represent a significant source of global carbon emissions and exhibit poor hydro-ecological function, exacerbating both the climate and biodiversity crises. Peatland restoration through drain blocking and revegetation is championed as a premier Nature-based Solution (NBS) for climate change mitigation and adaptation. However, empirical evidence quantifying the multi-faceted benefits of restoration, particularly its role in enhancing ecosystem resilience to drought, remains limited for many UK upland regions. This study presents a five-year (2018-2023) field-based investigation into the impacts of restoration on a degraded blanket bog in the North York Moors National Park, England. Key hydro-ecological metrics—including water table depth (WTD), dissolved organic carbon (DOC), CO2 and CH4 fluxes—across three distinct treatment areas: drained (degraded), recently restored (2 years post-intervention), and long-term restored (5 years post-intervention) were monitored. Results demonstrate that restoration interventions rapidly initiated recovery. Mean seasonal water table depth significantly increased (i.e., came closer to the surface) in the recently restored (-12.4 cm ± 3.1, p < 0.01) and long-term restored (-16.8 cm ± 2.7, p < 0.001) sites compared to the degraded control (-22.5 cm ± 4.8). Crucially, during the significant summer drought of 2022, the long-term restored site maintained a water table 35% closer to the surface than the degraded site, showcasing superior drought resilience. Concurrently, the restored sites transitioned from significant sources of CO2 (degraded: 2.41 t CO2e ha⁻¹ yr⁻¹) to carbon sinks (long-term restored: -1.82 t CO2e ha⁻¹ yr⁻¹). Methane (CH4) fluxes increased post-restoration but did not offset the carbon sequestration gains from reduced CO2 emissions. DOC concentrations in runoff water decreased by 42% in the long-term restored site, indicating improved water quality and reduced carbon loss. Study concluded that peatland restoration in the North York Moors effectively enhances ecosystem resilience to climatic extremes, significantly reduces atmospheric carbon emissions, and promotes a trajectory towards carbon sequestration, thereby validating its role as a critical NBS for regional climate adaptation strategies.