On February 1, 1959 the Academy of Sciences of the German Democratic
Republic founded the 'Forschungsstelle fUr Limnologie' (now Abteilung
Lim- nologie des Zentralinstitutes fUr Mikrobiologie und Experimentelle
Therapie der Akademie der Wissenschaften der DDR) in Jena and a research
laboratory at Lake Stechlin at Neuglobsow near Rheinsberg used as field
experimental station. The foundation followed the building of the first
nuclear power plant in the G D R ('Kernkraftwerk I der DDR') in the
period 1956-66 between Rheinsberg and Furstenberg (Havel). The nuclear
power plant is situated between two stratified lakes - Lake Stechlin and
Lake Nehmitz - far from any industrialized area in the midst of
extensive woodland. The cooling water is taken from Lake Nehmitz and led
away into Lake Stechlin, having passed through the cooling system of the
plant. The temperature is on average 10° C above the ordinary level.
From Lake Stechlin the water is led back to Lake Nehmitz (Schrader
1962). It was expected that the deep, oligotrophic Lake Stechlin would
be loaded thermally and materially by the cooling water circuit, meaning
that it would be 'eutrophized', while the slightly eutrophic Lake
Nehmitz would be 'oligotrophized'. Thus there would be a solid basis for
a research programme on fundamental limnological problems, the solution
of which could facilitate problems associated with improvement of
conditions in water resources.