In this paper, different aspects of species richness (inventory and differentiation diversity) are integrated from site-specific to landscape level, based on the land-use pattern. The partition of total species richness into additive components within and among communities is used as a unifying framework with which to measure richness at different levels. of. Based on the mosaic concept (Duelli, 1992), species richness in an agricultural landscape is decomposed into the contributions of the different types of land-use (habitat variability), the different patches within each type of land-use (habitat heterogeneity) and patch-specific species richness. An extensive data set was collected to derive components of species richness. The case study indicated clear differences between types of land-use, which results in scale effects when comparing typespecific species richness. By the partitioning of landscape species richness into additive components, the contribution of a landscape element can be compared within or between scale levels and interpreted individually in terms of scale-specific factors and processes. This may lead to a scientifically based evaluation of the potential for increasing biodiversity by appropriate landscape management.