Project Details
Microorganisms in the capillary fringe, rapidly changing environment
Applicant
Professorin Dr. Claudia Gallert
Subject Area
Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
Term
from 2007 to 2015
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 31352921
The influence of suspended or immobilized, biofilms forming microorganisms in capillary fringes (CF´s) on the physical behaviour (e.g. changes of hydraulic parameters, extent of the CF, water content) and changes of bio- or geochemistry in the soil-water-gas-interphase will be investigated in cooperation with water chemists (Frimmel/Abbt-Braun), geologists (Grathwohl), (soil) physicists (Vogel/Geistlinger) and mathematicians (Bastian/Ippisch) for modeling of experimental data. The lab work will include short term and long term experiments to elucidate pore size changes (bioclogging) by biofilm formation, capillary suction at mineralic/organic surfaces, changes in soil water content in the presence/absence of extracellular polymeric substances (EPS) or biosurfactants and bacterial movement. A technique to visualize and estimate (quantify) the bacterial distribution, activity and biofilm formation in a variably saturated porous medium (CF) by utilization of fluorescent substrates and natural or modified fluorescent bacteria with non-invasive techniques will be developed. The influence of suspended or immobilized bacteria in the CF on transport processes of oxygen coupled with biochemical reactions will be investigated and data will be used to model and predict the fate of a pollutant at fluctuating water tables and under different nutrition levels. When nitrate is used as electron acceptor subsequent nitrogen gas formation occurs during denitrification and the influence of gas bubble formation and disappearance on transport processes will be investigated.
DFG Programme
Research Units
Participating Person
Professor Dr. Josef U. Winter