Qualitative or quantitative description of the future by developing scenarios is a key method when taking a long-term view, e.g., up to 2050. Previously the time frames covered by the scenarios have usually been no more than 20 years. This period can be too short for achieving long-term goals when, for example, testing watershed management plans. This paper is an attempt to introduce and illustrate the potential of the Story-and-Simulation methodology and Fuzzy Cognitive Mapping when drawing up qualitative and semi-quantitative scenarios and the future of Lake Peipsi, one of the largest surface water bodies in Europe. The lake is shared between Estonia and Russia and consists of three unequal parts with different natural conditions and socio-economic problems in the catchment. The scenarios developed in cooperation by the stakeholders and experts were used for assessment of the importance of the major socio-economic and political drivers on water resources and water quality in the area. The results indicate that a stakeholders' panel could provide comprehensive expertise to develop scenarios. However, a participatory scenario development is likely to produce varying results depending on the composition of the stakeholders' panel.
Keywords: fuzzy cognitive map, large lake, public participation, socio-economic and political drivers, story-and-simulation approach