The Great Hungarian Plain is characterised by both unique natural values and intensive land-use. The on-going and future land-use changes may considerably affect ecological integrity, thus a further decline in biodiversity can only be avoided if nature conservation and socio-economic priorities are considered together. The overall objective of the proposed research is to assess the relationships between land-use, biodiversity and ecosystem functioning. In a collaboration between leading Hungarian research centers of botany, zoology, soil science, and agro-environmental research we plan (1) to conduct a detailed ecological and socio-economic evaluation of representative sites and (2) to regionalise our results to the whole Great Hungarian Plain based on data from a habitat mapping to be finished in 2005. The major outcome of the project will be an on-line expert sytem on landscape ecology and land-use, which provides recommendations on rural development and sustainable land-use. The expert sytems will integrate hundreds of high-resolution maps, dynamic modells, land management protocols, and thus make scientific results widely available and applicable.