Bengt Olsson

My research focuses on the environmental impacts of harvesting forest biomass for energy production, in particular how the extraction of stumps and logging residues (i.e., whole-tree harvesting) influence stocks of carbon and nutrients in soil and tree biomass of the following stand. Soil acidification caused by biomass harvesting, and the compensation by weathering and nutrient recycling with wood ash is studied in some projects. Studies are mainly performed in long-term field experiments where the oldest ones were established in the mid-1970s. I have also participated in several synthesis studies on how increased use of forest biomass for energy affects ecosystem services, and how it affects our ability to achieve national environmental quality goals, especially those related to acidification, eutrophication, climate, biodiversity and toxic substances in the environmental. Another research theme has been about tree species affects on carbon stocks in soil and tree biomass, both here in Sweden and in Mozambique.

I mainly teach in basic ecology, in particular ecosystems ecology, at undergraduate level for education programmes in biology, environmental science, economy and technology.

Major ongoing and recently finalised projects:

·      Effects of whole-tree harvesting at thinning and nutrient compensation with nitrogen and ash on carbon balances. 

·      Effects of stump harvesting, and site preparation with disc trenching or patch scarification on vegetation biomass and performance of planted spruce and pine saplings.

·      The role of weathering for sustainable forest production: Reducing uncertainties in estimating base cation weathering of Swedish forest soils (completed, part of the QWARTS project).

Activities in other projects:

·      A spatially explicit decision support model for stump harvesting. A multicriteria analysis including economic costs and revenue versus impacts on GHG emissions, and protection of biodiversity, soil and waters. (Swedish strategic research programme STand-Up for Energy.)

·      Chemistry of phosphorus in soils of managed forests. (Prof. J-P Gustavsson, Dept. of Soil and Water, SLU.)

·      Forest bioenergy harvest impact on soil nutrient and acdity status simuated with HD-MINTEQ. (Prof. Stefan Löfgren, Dept of Environmental Assessment, SLU.)

Background: Biology degree with specialisation in plant ecology from the University of Gothenburg. PhD in 1996 at SLU in Ecology and Environmental Sciences.

Principal supervisor for PhD students: Karna Hansson (2011), Benard Guedes (2017), Sophie Casetou-Gustafson (2019). Assistant supervisor for Therese Zetterberg (2015) and Marius Tuyishime (running).