Knol, Onno M.Rautenstrauch, ClausSchenk, Michael2019-09-162019-09-161999https://dl.gi.de/handle/20.500.12116/26590Agriculture in the Netherlands produces high emissions of minerals to soil and ammonia to air, which cause environmental problems. The CLEAN model is a tool to evaluate policy options to reduce these problems. An overview of the model is presented and the difficulties in calculating manure surpluses and manure destinations are highlighted. To fulfil its purpose the model needs to be rather detailed, use large amounts of data, be fast, and produce reliable results. The model concepts and information technology that were chosen to meet these requirements are discussed. Special attention is paid to the position of the model in a larger information system and the use of a relational database. The development of this environmental information system will be evaluated and based on this experience, some remarks will be made on model integration.Text/Conference Paper