Land use impact assessment of margarine

PURPOSE: This paper presents a case study of margarine, demonstrating the application of new characterisation factors (CF) for land use and a number of land use change impacts relating to biodiversity and ecosystem services. The objectives of this study were to generate insights as to the ease of applying these new factors and to assess their value in describing a number of environmental impacts from land use and land use change relating to the margarine product system. METHODS: This case study is a partial descriptive life cycle assessment (LCA) of margarine. The functional unit of the study is 500 g of packaged margarine used as a spread in the UK and Germany. The life cycle stages included were: agricultural production, oil processing, margarine manufacture and transportation to regional European distribution centres. Essential for the application of the new CF was the identification and quantification of the inventory flows for land occupation (land use) and land transformation (land use change) flows. A variety of methods have been applied to determine the inventory flows for the agricultural and industrial stages in the life cycle. These flows were then assessed using the new CF and land use-related environmental impact categories recommended in this special issue. RESULTS AND DISCUSSION: Land occupation was the major determinant for all the new impact categories with the exception of the water purification potential. Many of the impact categories followed a similar pattern and therefore, the inventory result for land occupation in this case study explains a large share of most of the impacts. Where land occupation alone is not a suitable proxy for environmental impacts (i.e. for freshwater regulation potential), differentiation at the level of biomes has proven relevant. In addition, the land use types distinguished so far were found to be useful in highlighting likely hotspots in the life cycle, although further differentiation of ‘agricultural land’ is suggested to account for the differences between annual and permanent crops. CONCLUSIONS: The new land use impact assessment methods applied help to identify hotspots in the life cycle of margarines, with different proportions and sources of vegetable oils. The specific impacts of each vegetable oil are determined mainly by the yield (and thus land occupation), but also by the type of agriculture (annual vs. permanent crops) and the sourcing location (and thus the sensitivity of biomes and occurrence of land use change). More research is needed to understand the usefulness of the various impact categories. For land use types, further refinement is required to describe different agricultural systems consistently across impact categories (e.g. annual vs. permanent cropping). In addition, the conceptual basis for the CFs applied in this case study (i.e. use of a potential reference for occupation and transformation) has limitations for some types of decisions normally supported by LCA.