Hydrology of the unsaturated zone

A better understanding of water transfer processes in the unsaturated zone (UZ) of soil is essential, whether for estimating runoff/infiltration partitioning in hydrological models or quantifying groundwater recharge in hydrodynamic models used in hydrogeology.
This course will focus on practical work on soil columns in the laboratory. After a reminder of the equations governing the transfer of matter in the NSA, an introduction to the modeling of transfers in the NSA will be given, using HYDRUS 1D software.
The practical exercises in this course involve experimenting under controlled conditions (known rainfall intensity and duration, known drought period, imposed surface load, column of sand or reworked soil with known particle size) with water transfer in an unsaturated medium, and continuously monitoring temporal changes in water content and water potential at various depths.

This course will focus on practical work on soil columns in the laboratory. After a reminder of the equations governing the transfer of water and
solutes in the ZNS, an introduction to the modeling of transfers in the ZNS will be given, using HYDRUS 1D software.

The practical work in this unit consists of experimenting under controlled conditions (known rain intensity and duration, known drought period, imposed surface load, sand column or
of reworked soil with known granulometry) with water transfer in an unsaturated medium and continuously monitoring the temporal evolution of water content and water potential at several depths.

The objectives of these practical exercises are multiple:

• Gain a qualitative understanding of the notion of capillarity in soil and its impact on infiltration processes.
• Understand the notion of water potential and water content in an unsaturated environment and how it changes following a rainy episode or a period of drought. 
• Understand the relationship between water content and water potential, 
• Estimate the volume of water infiltrated and the useful reserve based on water profiles before and after infiltration.
• Provide a complete dataset to calibrate a simple 1D hydrodynamic flow model in the NSA (using HYDRUS 1D).

EU "Water cycle"; EU "Functioning of hydrosystems".

• Written exam (final test): 60%.
• Oral (TP CR): 40