Lake Ringsjon: its catchment area, its history and its importance

The aim of this chapter is to present a general description of Lake Ringsjon and its catchment area, serving as a background for the following, more specific chapters. We briefly describe human activities and land use, as well as the human demographics in the catchment area. Moreover, we present important historical events behind the development and present status of Lake Ringsjon. Finally, we describe the importance of the lake as a production unit for 'ecological services', including not only production of fish and drinking water, but also in terms of recreational value, such as swimming, fishing and bird-watching. Although these 'services' are nowadays of less importance in Lake Ringsjon than 40 years ago, due to the eutrophication problems, the lake has the potential to once again become a centre for human activities.