A comparison of three methods to assess land use impacts on biodiversity in a case study of forestry plantations in New Zealand

Journal article, 2014

Purpose: The aim of this study is apply available methods to assess impacts on biodiversity from the land use caused by plantation grown radiata pine in New Zealand in a life cycle assessment framework. This is done both to quantify the impact as well as compare the results obtained by different methods. Methods: Data on location and productivity for wood supply regions in New Zealand was assessed using three methods identified as relevant for the purpose. All data were related to a functional unit of 1 m3 of timber production. Results and discussion: The results show both a significant difference in impact on biodiversity from land use in the different wood supply regions and a significant difference in the results from the three applied methods. Although some of the results obtained from the three methods were correlated, this was not consistent through all the results. The methodological variation emanates from the treatment of the characteristics of the wood supply regions and underlying assumptions, e.g. reference vegetation. Compared to a case study in Norway, the impact on biodiversity from plantation forestry in New Zealand is found to be relatively low following the applied methods and assumptions taken. Conclusions: The study shows a significant variation in how impacts on biodiversity are assessed following different approaches. Research to harmonize methods to quantify impact on biodiversity is recommended, as well as exploring effects of different weighting of crucial aspects of biodiversity, such as rarity, abundance and species richness.