Bacterial Colonisation Patterns in Ground Water Simulation Filters under the Influence of Humic Substances

The object of the following examinations was to find an explanation which role humic substances (HS) play within the process of bacterial colonisation in ground water and how their influence it. For long-term investigations a batch-reactor which simulate a ground water biotop was developed. More than 800 strains were isolated as pure cultures and 600 thereof examined according to their morphological, physiological, chemotaxonomical and genomic properties. Transformations of the HS were detected by acid-hydrolysis, LC-DOC-Detection and pyrolysis-fieldionisation-mass-spectrometrie. The scanning-electron-microscopie SEM was used to discribe the formation of the biofilm.In summary the following results were prooved:- The communities of the reactors as well as most of the isolated strains were able to use the HS as a sole carbon and energy source. - The HS led to decline in the diversty patterns.- The the isolated strains of the ground water showed a higher physiological activity than those isolated from the reactors.- Drastic changes occured according to the morphological and physiological properties of the isolated strains.- The influence of the HS on the diversity and colonisation patterns were stronger in the aquatic phase.- The communities were dominated by only a few species.- Bacterial transformations on the HS were proved by acid hydrolysis, LC-DOC and Py-FIMS without clear similarities in the results of this three methods.- REM images showed no differences according to the biofilm in both reactors