Hybrid gravimetry to map water storage dynamics in a mountain watershed

Mountain hydrosystems contribute significantly to the water supply of populations and constitute ecosystems with a rich biodiversity. They are identified as sentinels of climate change, in the sense that they are particularly vulnerable to small perturbations of climate variables. It is therefore necessary to determine their current hydrological functioning, in order to assess their vulnerability to climate change and to propose adaptation measures.

However, due to the high variability of water stocks in space and time, monitoring the dynamics of water stocks in mountain watersheds is complex. The deployment of in situ measurement networks is therefore essential. Among the different in situ observation methods available, gravimetry is an adequate method because it allows direct monitoring of water stock variations at an intermediate measurement scale (i.e., within a radius of a hundred meters around the stations). We have implemented such a gravimetric monitoring on a network of 16 stations with a step of 1-2 months and over a period covering more than two hydrological cycles on the small (80 ha) Strengbach watershed (Vosges, France).

From an observational point of view, the study shows the contribution of hybrid gravimetry to the understanding of the dynamics of water stocks in mountainous areas.

This news is an extract of an article published in the last issue of the Résif Newsletter (in french only).

To know more

Lettre d’information Résif n°20, décembre 2021

Dispositif de suivi gravimétrique hybride du bassin versant du Strengbach. A) Carte d’instrumentation. B) Intérieur de la station de mesure avec l’emplacement de l’iGrav#30 et de la station de référence pour les mesures relatives. C) Une station de mesure du réseau micro-gravimétrique.

Hybrid gravity monitoring of the Strengbach catchment. A) Instrumentation map. B) Interior of the measuring station with the location of the iGrav#30 and the reference station for relative measurements. C) A measuring station of the micro-gravimetric network. © Chaffaut, Q., Lesparre, N., Masson, F., Hinderer, J., Viville, D., Bernard, J.D.,Ferhat, G., Cotel, S. (2021b). Hybrid gravimetry to map Water Storage Dynamics in a mountain catchment, Frontiers in Water. Accepted for publication ( 2021).