Short Term Effects of Soil Disturbance on Greenhouse Gas Fluxes on a Nutrient‐Rich Peatland After Clearcutting

ABSTRACT Forestry drained peatlands are currently a large source of greenhouse gas (GHG) emissions and expected to lose carbon (C) storage in long‐term. The GHG emissions and soil C stock are affected by management practices. In rotation forestry, soils are prepared with machine for regeneration after clearcutting. However, little is known about how the soil disturbances affect GHG emissions from soil. This study examines the effects of mounding on the soil GHG fluxes in a nutrient‐rich drained peatland forest in southern Finland. Carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) fluxes were measured on disturbed (mounded) soil surfaces and unprepared soil surfaces over three growing seasons after soil preparation. In addition, water table (WT) level and soil temperature were measured to investigate the drivers of the gas fluxes. CO 2 fluxes were not impacted by mounding treatment, while CH 4 and N 2 O fluxes were significantly higher on the mounds compared to the unprepared surfaces. Soil temperature was the major parameter controlling CO 2 fluxes. No significant relationships were found between CH 4 and N 2 O fluxes and the measured environmental factors. This study provided evidence that on peatland soils, disturbance increases CH 4 and N 2 O emissions to the atmosphere and has climate warming effects, highlighting the importance of monitoring all GHG fluxes from varied surfaces after clearcutting and soil preparation to better estimate the climate impacts of rotation forestry on peatlands.