Fig. 4.
Scheme of the distribution of Askenasia chlorelligera, Balanion planctonicum and Urotricha cf. castalia in the alpine lake Gossenköllesee during the ice-free summer period indicating the main factors involved. Drawings modified from Remane et al. (1986), Streble and Krauter (1988) and Foissner et al. (1999). For details see text.