Mass transfer of oxygen across the capillary fringe [Elektronische Ressource] / vorgelegt von Sanheng Liu

Mass Transfer of Oxygen across the Capillary Fringe Dissertation zur Erlangung des Grades eines Doktors der Naturwissenschaften der Geowissenschaftlichen Fakultät der Eberhard Karls Universität Tübingen vorgelegt von Sanheng Liu aus China 2008 Tag der mündlichen Prüfung: 30, 05, 2008 Dekan: Prof. Dr. Peter Grathwohl 1. Berichterstatter: Prof. Dr. Peter Grathwohl 2. Berichterstatter: Prof. Dr. Ulrich Mayer Abstract Mass transfer of oxygen from soil air across the capillary fringe affects the fates of many contaminants in groundwater. The processes involved in mass transfer include aqueous and gas phase molecular diffusion, mechanical dispersion, reaction and partitioning between the aqueous and gas phases. The extent to which each of these processes contributes to mass transfer between the saturated and unsaturated zone depends on both the properties of the solute and the conditions within the subsurface. It is generally believed that transversal mixing controls the flux of electron acceptors such as oxygen across the capillary fringe into groundwater. The objective of this work is to investigate the transfer of oxygen between soil gas and groundwater.