Gustaf Egnell, Researcher, Swedish University of Agricultural Sciences
My research, teaching and extension falls within the field of bioenergy from conventional forestry, with main focus on effects of more intensive biomass harvest regimes – i.e. harvest of small diameter trees, logging residues, and stumps for energy purposes – on long-term site productivity. Part of that story includes the potential need to compensate for nutrient losses (soil buffering capacity loss) following more intense harvest regimes as recommended by the Swedish Forest Agency, that recommends ash recycling after harvest of the nutrient rich branches and tops. My approach is applied and I follow the development of the stand in a number of long-term field experiments where small diameter trees, logging residues, and stumps have been removed and/or where the nutrient loss has been compensated for with wood-ash or NPK-fertilizers. Recently I have focused more on the potential of the young, nitrogen limited soils in boreal and temperate Sweden, to compensate for loss of mineral nutrients and buffering capacity through weathering, and the carbon balance (greenhouse gas benefits), when biomass from long-rotation forestry is used for energy purposes.