Tufa
springs: The role of algae for bio-calcification (2006-2012)
Research
questions
Limestone-depositing
springs are mostly characterized by ground waters oversaturated in CO2
and calcium carbonate / hydro-carbonate fractions what leads to precipitation
of calcite, or more rarely of aragonite and magnesian calcite. We hypothesize
that these environments are unfavourable for the majority of benthic organisms
except a few taxa from variable evolutionary affiliations which have developed
strategies to cope with this situation. It remains unclear to which extent
biotic interaction by algae influences the quality of the deposited
calcification product and which specific adaptive strategies are effective for
individual organisms. Within the actual approach the details of the specific
morphological and ultrastructural characters of biocalcifiers are studied
including temporal and spatial variability of the organisms. The focus is on limestone-tufa
springs and related spring-streams of the Alps.
The specific character of “cool” (non-thermal) limestone-depositing springs is
supplemented by comparative studies of calcifying biota of thermal springs.
Funding LBV (Landesbund für Vogelschutz, Bayern) Natural
Science Museum Trento (Italy)
