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Topical - Geoheritage
geologists, geographers, chemists, physicists
and others.
The Croatian Geological Institute, with
collaborators, was responsible for the geological
mapping and the Faculty of Science,
University of Zagreb is continuously present
with various teams studying geological and
ecological factors.
The Veterinary Faculty, the Faculty of
Forestry and the Faculty of Agronomy in
Zagreb are also involved. Research teams
from the Croatian Academy of Science
are monitoring the biota. Scientists from
the Institute Ruđer Bošković introduced
radiometric and isotope analyses, and this
team is permanently studying and publishing
on the area (e.g. Horvatinčić et al.,
2006; Obelić et al., 2006; Obelić 2011). The
Plitvice Lakes have several times been the
subject of dissertations (e.g. Barešić, 2009),
and the research process is ongoing.
Evidence of natural and anthropogenic
processes
Natural processes
Lakes in general are very sensitive environments,
due to their close interactions
with surrounding areas. Complex processes
of sedimentation and dissolution of limestone
require specific climatic preconditions.
Weather and temperature factors are
of great importance, as well as the water
quality and other natural factors. For precipitation
of calcium carbonate the water
saturation level needs to be higher than 3,
and the pH value of water must be above
8.0. In modern times the deposition rates
(average 13 mm per year) have exceeded
the dissolution rates (0.001-4 mm per year),
enabling the accretion of tufa barriers and
the formation of new lakes, but at the same
time resulting in lake-level rise in the Upper
lakes and fall in the Lower lakes (Figs 3,
5, 6). Plants indirectly contribute to tufa
formation. Mosses, algae and cyanobacteria
Figure 1: Position and topographic map of the Plitvice National Park (Basic topographic map of
Croatia, sheet Bihać 420-1).
Figure 2: Forests cover 75 % of the Park. Čorkova
uvala with Čorkovo vrilo spring is a locality with
protected virgin forest, July, 2012.
Figure 3: Cross section of the Plitvice Lake System with simplified water cycle (based upon: Petrik, 1958;
Polšak et al., 1976; Božićević, 1994).
European Geologist 34 | November 2012
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