1982; TUNDISI 1990). Therefore a modified nutrient loading
concept was developed for tropical South American lakes by
the Centro Panamerican de Ingenieria Sanitaria y Ciencias
del Ambiente (CEPIS 1990). However the application of this
model to tropical high mountain lakes is questionable, and
nothing has been learned about eutrophication processes in
this type of lake.
Investigations are carried out at Lake San Pablo, Ecuador,
in the high Andes. The aim of this study is to describe the
limnological processes of this type of lakes under considera-
tion of the eutrophication processes. This includes the turn
over of the nutrientes, the limitation of primary production as
well as the succession of phyto- and zooplankton.