PosterPDF Available

Seasonal variation in chemical exchanges between a river and a meander floodplain

August 2018

DOI:10.13140/RG.2.2.20436.65929

Conference: Goldschmidt con2018

Authors:

Antoine Biehler

Observatoire global du Saint-Laurent - Réseau Québec maritime

Gwénaëlle Chaillou

Université du Québec à Rimouski UQAR

Thomas Buffin-Bélanger

Université du Québec à Rimouski UQAR

Institute of Research for Development

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Understanding the extent and the nature of groundwater-surface water connectivity is crucial for sustainable management of water resources. This connectivity implies a mixing zone between water located above and below the surface that corresponds to the hyporheic corridor. The direction and magnitude of water exchanges within the hyporheic corridor are mainly controlled by the fluctuating river flow stages and the changing hydraulic gradient of the water table in response to seasonal hydrological conditions. However, the impact of river stage on aquifer geochemistry in the hyporheic corridor is still not well known. The objectives of the poster are to determine the spatiotemporal variability of the mixing zone and to determine the mixing rate in the floodplain.

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