Hydrological dynamics of a Northern cultivated peatland and implications for management

Cultivated peatlands play a significant role in grass and dairy production, particularly in Northern regions. However, agricultural activities on these organic soils often lead to undesirable environmental effects, namely increased nutrient leaching and greenhouse gas (GHG) emissions. The hydrological characteristics and dynamics of cultivated peatlands significantly influence the formation of leachable nutrients and GHGs. Currently, there is a gap in the comprehensive understanding of hydrological responses in these cultivated areas. To address this gap, the NorPeat research platform at Ruukki research station, managed by the Natural Resources Institute Finland (Luke), has been established in Northern Ostrobothnia, Finland. The site features varying peat thickness (10-80 cm) over a mineral subsoil and a subsurface drainage system consisting of perforated pipes installed within the mineral layer at a depth of 120-130 cm from the surface. Continuous hydrological monitoring of key parameters such as groundwater table, soil moisture, drainage discharge, precipitation, and soil temperature has been ongoing on the platform since 2016. In this study, we focus on the dynamics of the groundwater table and soil moisture in response to seasonal variations, soil structure, and land management; to establish a comprehensive water balance quantifying water fluxes (evapotranspiration, drain flow, overland flow) to the adjacent stream; and to develop a hydrological conceptual model of the field. The outcomes of this research are expected to improve our understanding of cultivated peatland hydrology, inform future studies on environmental impacts, and provide valuable data for both farmers and policymakers.