Modelling multiple objectives of land use for sustainable development

Sustainability is a human-centred concept that comprises multiple aspects and objectives of different interest groups. Sustainable development is not readily measurable, except as a compromise between different parts of society, of which some may try to represent future generations of mankind. To determine a sustainable development path in the relationship between agriculture and its natural environment, a profound knowledge of this complex system and its behaviour under different socio-economic conditions is necessary. We present a modelling system which consists of a set of hierarchically linked modules. These modules describe production activities in a way that allows an economic and ecological analysis of these techniques. The heart of the modelling system is a multiple goal linear programming model, which is generated by data base modules. Simulation of single farm models as well as regional models based on simultaneously optimised farm types is possible. The modelling system appears to be a highly flexible tool with respect to the number and type of farms, sites and production techniques. Environmental objectives can easily be included and different levels of goal achievement can be simulated. It is well suited for single farm analysis as well as for regional models, for static as well as dynamic approaches. It allows rapid adoption of the model and rapid calculation of scenarios. Therefore, it is suited for use in interactive environments with users who are interested in repeated runs with little changes in the goal function, prices, subsidies or technical coefficients. The results can be used for policy decisions as well as the strategic planning of individual farmers. Applications of the modelling system will be presented in following papers. In this paper the kind of information the model can generate and the circumstances of their usage are shown.