Time: 13:30-14:30, 22nd November (Thursday)
Venue: Lecture Hall 221, ISESS (Building No. 16), Tianjin University
Speaker: Professor Francois Chabaux from the University of Strasbourg
Abstract:Modeling the variability of the water geochemical composition at a watershed scale requires the development of modeling codes able to cross hydrological and geochemical processes. The aim of the presentation is to show the hydro-geochemical modeling approaches developed at LHyGeS, Strasbourg, France, to study the origin of spatial and temporal variations in the chemical composition of surface waters at the scale of an elementary watershed, the Strengbach Critical zone Observatory (OHGE). Will be presented 1- the application of the 1D thermo-kinetic code KIRMAT (KInetic Reactions and MAss Transport) for simulating the geochemical variations of the Strengbach spring waters over the last 25 years (Ackerer et al, 2018) and 2- the recent results obtained by combining a hydrological depth-integrated and spatially distributed model (NIHM) with the reactive-transport model (KIRMAT). This coupling allows for modeling the spatial and temporal simulation of the flow trajectories, the flow rates, the weathering reactions and the evolution of the water chemistry within the watershed. One of the consequences of these recent studies is to demonstrate that the chemostatic behavior of the spring chemistry in the Strengbach catchment is a direct consequence of the strong hydrological control of the water transit times within the catchment.