Evaluating the global warming potential of harvested wood due to the carbon stock changes under different forest management practices

Abstract

The European forests are essential in achieving the land use and land-use change (LULUC) related CO2 removal targets. Adoption of various harvesting practices significantly influences the overall LULUC emissions and removals of forests. In this study, we used the life cycle assessment (LCA) approach to systematically evaluate the land use and land use change-related emissions and removals (GWPLULUC) of harvested wood raw material. We applied different case study scenarios with different forest management practices in Finland in comparison to the business as usual scenario (one pre-commercial thinning and two commercial thinnings): i) a scenario with no pre-commercial thinning, ii) a scenario with reduced thinning with longer rotation cycle, and iii) a scenario with collection of logging residues. We also explored the effect of management on land occupation. We modeled various scenarios using the MOTTI stand simulation for birch, spruce, and pine, encompassing different vegetation types across various regions of Finland. This was followed by soil carbon modelling using the Yasso07 model to assess the effect of residue collection for spruce. Our analysis indicated that the management effects on GWPLULUC emissions and removals vary across regions, vegetation types, and management practices. Especially, reduced thinning with longer rotation cycles results in significant carbon removals and lowest land occupation due to the longest rotation cycle (except for birch). The collection of residues leads to small losses of soil organic carbon, but the effect was a negligible factor in the overall GWP of wood raw material. These findings underscore the intricate interplay between regional, species-specific, and management-related factors in shaping the GWPLULUC of forest-based products.