Session: Impact Assessment

An improved method to calculate Land Use effects on endpoint level
An De Schryver,^*   PRe Consultants
Mark Goedkoop,   PRe Consultants

For several years, the impacts of land cover changes on ecosystems are a topic of wide interest in LCA. Unfortunately, until now, no ultimate desirable method has been found and different limited methods are used next to each other. Within the framework of the ReCiPe Project (a cooperation between Radboud University of Nijmegen, Centrum voor Milieukunde Leiden-CML and PRé Consultants), a new method is developed to calculate the damage to ecosystems caused by the effects of occupation and transformation of land.

The goal of this project is to link midpoints (CML) and endpoints characterisation factors (Eco-indicator 99) and to update the underlying methods and data used in the methodologies. For this impact category, we have not yet been able to make a link from midpoints to endpoints. As a result, only the calculation of endpoint characterisation factors will be discussed in this paper. The endpoint indicator for land use describes the loss of species diversity, expressed in Potentially Disappeared Fraction (PDF) of species, due to occupation or transformation. Because the PDF is influenced by the species-area relationship (S=cAz) we took a closer look at the c and z factors to be used in this relation and implemented a different z for each different land use type and area size. Furthermore, special attention is paid at agricultural areas. The fact that the main species richness of an arable field is relatively independent of what grows on the field, but is determined by the edges, made us decide to use the species richness in the boundary of the agricultural area to calculate the PDF of the total field. As a result, three archetypes of land use intensiveness are distinguished: monocultures, intensive and extensive areas. For the calculations, the work of Koellner (2006), the Countryside Survey 2000 (UK), and Crawley and Harral (2001) is used. The resulting method is transparent and novel to its kind because of the inclusion of both midpoint and endpoint characterisation factors and three archetypes of land use intensiveness.

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