Tufa and Cascades

Tufa makes the Una so beautiful

Throughout its almost entire flow the Una is the river of cascades. Tufa formations such as cascades, river aits, white-water passages, rapids and (combined with tectonic movements) waterfalls represent the most prominent features of this unique river. Waterfalls of different sizes and forms attract numerous visitors, inspire artists but are also of great interest to scientists from different fields of study.

Emergence of tufa

Precipitation of tufa in clear natural waters is caused by a combination of different physical, chemical and biological processes in which carbonate mineral - calcite, dissolved in waters of karst landscaped, is deposited. The process of tufa creation is rigidly conditioned by diverse biotope features which encompass pH, temperature, calcite saturation, concentration of calcium and magnesium.  Tufa emerges from solvable calcium-carbonate of the waters of this karts region, in a process in which, through turbulences of clean and cold water and its evaporation, calcium-bicarbonate releases carbon-dioxide and precipitates calcium-carbonate.


Precipitation of tufa is hastened by phytogenic processes, mostly by carbon-dioxide consuming algae. Thus the algae stimulate the precipitation of calcium-carbonate which is deposited on them, as well as on moss, leaves and tree branches. Due to its specific biological features tufa biotope is considered to be one of the most distinctive and unique forms of freshwater biotope. Excluded the higher plants and diatomeas, the cascades of the river Una are home to 42 species of different plants, 25 of which are algae and 17 moss variations. Due to its importance in tufa creation, the mosses are often regarded as tufa-creators.

Protection of Tufa

Being a process which is highly dependable on natural balance, we must protect and preserve tufa formation from the decrease in river water levels, water pollution, climatic changes and other forms of misbalance which can thwart and even completely block natural process of tufa precipitation and formation in the river Una. In order to protect and preserve the Una and its tufa formations we must insure that the tufa creation processes are maintained and undisturbed.