Original paper

Composition of groundwater nanoprotist communities in different aquifers based on aliquot cultivation and genotype assessment of cercomonads

Loquay, Nina; Wylezich, Claudia; Arndt, Hartmut


Investigations into the protistan fauna of groundwater habitats are still underrepresented. We investigated 14 aquifers comprising studies in lowlands around Cologne, the Eifel Mountains and the Alps (depths ranging from 6 to 400 metres) with different abiotic conditions. 21 heterotrophic flagellate taxa, five ciliate, four amoeba taxa and one centrohelid heliozoan were recorded. There was no clear relationship between protozoan communities and abiotic parameters at the different sampling sites with the exception of bicosoecids and euglenids that were more abundant at higher nitrate/chloride concentrations. The abundance of cultivable protists in free aquifer water ranged between 0.1 and 3 ind/ml. At one sampling site, abundances in free and sediment-associated water were compared revealing a ten-times higher abundance in the latter. The diversity of genotypes was investigated for cercomonads. Studies of Cercomonas and Paracercomonas D3-D5 LSU rRNA sequences indicated that groundwater may be a habitat with a relatively large diversity of species. A high number of species is probably not yet discovered.


groundwaterpollutionnanofaunaheterotrophic flagellatesprotozoacercomonasdiversityd3-d5 domain of lsu rrna