FWF Project: Microbial Community Dynamics in Alpine Karst Aquifers

Project outline
Collaborators: NIOZ, Netherlands Institute for Sea Research, Texel, The Netherlands, Dept. Microbial Ecology, Technical University of Berlin, Germany

Karst aquifers are particular types of groundwater ecosystems, showing unique characteristics in terms of hydrogeology, biogeochemistry and vulnerability. In contrast to porous media aquifers, karst aquifers with their discrete rock fractures and large conduits exhibits distinct and very dynamic discharge characteristics from their respective catchment areas. Karst aquifers are thus particular susceptible to environmental impacts and changes. A lot of effort is put into the development of protection strategies in order to maintain high water quality; but thorough understanding of karst-aquatic environments is a complex subject and demands for multiple scientific disciplines. In alpine areas like Austria, groundwater resources from alpine karst aquifers play a fundamental role for high quality public water supply. So far, investigations on microbial communities in alpine karst ecosystems have focused almost exclusively on a small fraction of microbes, namely on microbial fecal indicators. This lack of of knowledge is sharply contrasting the general considered importance of microbes for ecosystem prossesses such as energy- and matter flux. The proposed research project will bridge those gaps by addressing the following issues: i) The general characterisation of the abundance and dynamics of total prokaryotic-, protozoan-, and viral number direct counts from spring water of representative alpine karst aquifers, ii) the determination of the genetic eubacterial community structure and dynamics of the dominant spring water populations, iii) the assessment of the discrimination ability between the eubacterial autochthonous- and transient microbial endokarst communities, iv) and the comparative analysis between the genetic community structure of the attached- (i.e. the biofilm) versus the suspended eubacterial communities. In the proposed study it is hypothesized that knowledge based on autochthonous microbial communities (AMEC) and transient microbial endokarst communitis (TMEC) will help to i) brigde the gap between different karst compartments and the catchment area and thus extending the concept of carst systems, ii) to sumplement exisitng vulnerabilty assessment approaches, and iii) to provide the scientific basis for a total microbial community based spring water quality assessment for drinking water such as for bottled water production.