Lysimeter platform

Context

The lysimeter is a multi-scale study site made of two parts: a cultivated field and a large scale (about 10 m3) lysimeter built around an undisturbed soil volume. Both parts are equipped with permanent measurement devices for the continuous monitoring of ground- and soil water. This platform is designed for the quantification of water flows in soil (infiltration, slow and fast drainage, root uptake, groundwater recharge) at different scales. This facility is also used so as to test geophysical methods when applied in the unsaturated soil (electrical tomography, self potential, impedance spectroscopy, groundradar). Finally, it is a support for practical teaching in the framework of the master entitled “Fluxes in the groundwater-soil continuum” of the University of Avignon (UAPV).

Scientific objectives

Water flow and solute fluxes in structured soils are still far from being fully understood. Validation of predictive models including preferential flows or spatial variability of hydraulic properties is not yet acquired. This specific facility allows to address this issue. The lysimeter platform represents a major experimental support. Scientific programs related to the multi scale quantification and prediction of water balance (from the laboratory to plot) relies on this facility. A number of variables of interest, hydrological (rain, water profiles) and hydrogeological (water to water quality and piezometric level), have been continuously measured for several years. Spatial variability of the field is estimated through the use of geophysical methods and various soil sampling.

© EMMAH

The equipment of the site is
 

at the Field scale (6400 m²): presence of an alluvial ground water between 4 and 6 m depth, device for irrigation and crops.

• 3 sites for water balance characterization (tensiometry and soil moisture profiles, rainfall amount).
• sampling of soil water at two plots for the analysis of solutes profiles.
• 28 access points to the groundwater layer

at the Lysimetescale (~ 5 m² section, ~ 2.5m depth): continuous recording of tensiometry, soil moisture (capacitance probes) and rainfall, 2 automatic flow meters measuring the drainage flows at two depths (slow drainage and rapid flow). Equipments for the monitoring are complemented by specific equipments according to the conducted researches (rain simulator to analyse runoff/infiltration processes, stereophotography to estimate soil surface characteristics, electrical resistivity tomography and water extraction of plants...).

Scientific leaders

Stéphane Ruy, researcher

04 32 72 22 37, ruy@avignon.inra.fr
Claude Doussan, researcher

04 32 72 22 38, doussan@avignon.inra.fr
Technical Manager :

Franck Tison, engineer assistant

04 32 72 22 39,  franck.tison@avignon.inra.fr