A comparison of two different biodiversity assessment methods in LCA—a case study of Swedish spruce forest

Lately, there has been a growing interest in how to include biodiversity in life cycle assessment (LCA). The aim of this study was to compare two impact assessment methods, with regard to their applicability on a regional level and their feasibility in terms of data availability, through applying them to a case study.

The methods tested were those developed by de Baan et al. (2013a), based on species richness, and Lindner et al. (2014), based on ecosystem indicators. These were applied to commercially managed spruce forest in the south of Sweden. For the species-based method, characterization factors (CFs) were based on species richness of vascular plants in the region, calculated for two different stages in the production cycle, before and after felling, and using two different types of semi-natural reference situations. The key feature in the ecosystem approach was a set of indicators of prerequisites for biodiversity, based on expert knowledge, and the reference situation applied was the hypothetic maximum biodiversity quality in the region.

The results showed that both methods were applicable for biodiversity assessment at regional level. All methodological requirements, such as species data and expert opinion, were available. To obtain enough data for the species richness method, data on vascular plants from two administrative regions was needed. When biodiversity was assessed before felling and using the spruce reference situation, the conventional spruce forestry studied was shown to have positive impact on biodiversity. All other results showed negative impacts on biodiversity. The positive impact indicated by the species richness method was probably due to the small difference in species richness between the mature spruce forest assessed and the available spruce forest reference situation.

The study shows that the two methods are applicable on a regional level, although data availability was a constraint in the species richness method by de Baan et al. (2013a). The choice of reference situation, and when in the production cycle assessment was made, led to considerable differences in the characterization factors generated.