An expert system for integrating biodiversity into agricultural life-cycle assessment

Decision-making for nature-friendly land use in farming landscapes requires methods and indicators for assessing effects on biodiversity. We developed an expert system for including biodiversity (i.e., organismal diversity) as a life-cycle assessment (LCA) impact category in agricultural production. The method developed is valid for grasslands, arable crops and semi-natural habitats (SNHs) of the farming landscape, and allows us to estimate the impact of management systems on biodiversity. Eleven indicator-species groups or ISGs (flora of crops and grasslands, birds, mammals, amphibians, snails, spiders, carabids, butterflies, wild bees, and grasshoppers) were selected on the basis of ecological and life-cycle assessment criteria. Inventory data on crops, SNHs and agricultural practices with detailed management options were specified. A scoring system estimating the suitability of the farmland crops and SNHs as habitats as well as the reaction of each indicator-species group to the management options was developed. A case study calculated biodiversity scores for grassland along an intensity gradient, as well as those for winter wheat in the case of various cropping systems. The results allowed us to identify management options expected to have a major impact on biodiversity. The number of species observed during a plant and grasshopper survey showed high correlations with the scores derived from the detailed management activities. The use of 11 indicator-species groups allowed a differential, comparatively comprehensive assessment of the impacts of the agricultural practices on biodiversity. Production systems can be compared in terms of their potential impact on biodiversity, which may in turn enable us to make recommendations for good practice. We conclude that the expert system can also be used to investigate land-use scenarios at farm level, as well as on a regional scale.