The environmental impact of land-use can be expressed in terms of a change in biodiversity of flora. We present two models that characterize the negative effects of land-use: a model on the basis of species richness; a model on the basis of the rarity of ecosystems and their vascular plants. Each of those models may serve in the EIA (environmental impact assessment) of the urban and rural planning of expanding cities, industrial areas, road infrastructure, etc. Moreover, these models might be applied by Life Cycle Analysis (LCA) practitioners to incorporate the aspect of land-use in the environmental assessment of a specific product design. The results of both models have been applied in practice. Maps of The Netherlands are provided for both models. The map based on the rarity of ecosystems differentiates the best of what experts (biologists and ecologists) define as botanical quality of nature; the methodology is operational in The Netherlands and might be applied to other countries as well, however, detailed botanical information is required. The map based on species richness has a weaker compliance with the botanical quality of nature, however, the model can more easily be applied to a wider area of the world, since indicative data about species richness is available on a global scale. The so called 'eco-costs of land conversion' is proposed as a single indicator, being the marginal costs of prevention (or compensation) of the negative environmental effects on biodiversity caused by change of land-use. These 'eco-costs of land conversion' for the botanical aspects are part of the much broader model of the eco-costs/value ratio, which has recently been published in this journal [Vogtlander et al., Journal of Cleaner Production 2002; 10:57-671]. (C) 2003 Elsevier Science Ltd. All rights reserved.