%0 Articles %T Maximizing peatland forest regeneration success at lowest cost to the atmosphere: Effects of soil preparation on Scots pine seedling vitality and GHG emissions %A Pearson, Meeri %D 2013 %J Dissertationes Forestales %V 2013 %N 159 %R doi:10.14214/df.159 %U http://dissertationesforestales.fi/article/1942 %X This dissertation investigated the impacts of soil preparation after clearcutting Scots pine (Pinus sylvestris L.) forest on thick-peated soil from silvicultural and climatic standpoints. Three growing seasons after outplanting, mounding most effectively secured seedling survival, growth, and vitality through improved soil aeration of the planting spot. However, other presumed benefits of mounding to seedlings such as warmer soil temperatures and faster organic matter decomposition were not confirmed here. Regeneration in scalps was unsuccessful due to waterlogged soil. Importantly when scalping, only the humus layer should be scraped off without creating depressions in the peat. Seedling tolerance to desiccated as well as waterlogged peat soil over one growing season was remarkable in controlled conditions as mortality remained low. Drought stress was, however, plainly evident in seedlings as root and shoot growth, fractional colonization of ectomycorrhizal fungi, and root hydraulic conductance were all reduced. Nevertheless, maintenance of rather high photochemical efficiency (Fv/Fm) especially in current-year needles despite harsh drought seemed to indicate a potential for seedling recovery. Polyamine analysis also revealed that new needles are preferred in protecting the different parts of the seedlings against drought stress. Conversely, wet-stressed seedlings exhibited few signs of suffering. It was also demonstrated how the experimental environment—a controlled versus field setting—influences seedling tolerance to stress. The differing moisture levels within comparable microsites—dry vs. wet scalps and ditch vs. inverted mounds—had little influence on seedling growth and condition although physiological upset (i.e., Fv/Fm) was evident within scalps. Namely, the wetter the soil was, the lower Fv/Fm was. The fear of soil preparation accelerating GHG emissions, particularly CO2, from peat into the atmosphere appears unwarranted at least on nutrient-poor, boreal forestry-drained peatland sites. The overall climatic impacts of mounding and scalping three years after application were neutral compared to leaving soil unprepared.