Leduc Christian, Bromley J., Schroeter P. (1997). Water table fluctuation and recharge in semi-arid climate : some results of the HAPEX-Sahel hydrodynamic survey (Niger). In :
Goutorbe J.P. (ed.), Dolman A.J. (ed.), Gash J.H.C. (ed.), Kerr Y.H. (ed.), Lebel Thierry (ed.), Prince S.D. (ed.), Stricker J.N.M. (ed.). HAPEX-Sahel. Journal of Hydrology, 188/189, p. 123-138. ISSN 0022-1694.
Titre du document
Water table fluctuation and recharge in semi-arid climate : some results of the HAPEX-Sahel hydrodynamic survey (Niger)
Année de publication
1997
Auteurs
Leduc Christian, Bromley J., Schroeter P.
In
Goutorbe J.P. (ed.), Dolman A.J. (ed.), Gash J.H.C. (ed.), Kerr Y.H. (ed.), Lebel Thierry (ed.), Prince S.D. (ed.), Stricker J.N.M. (ed.) HAPEX-Sahel
Source
Journal of Hydrology, 1997,
188/189, p. 123-138 ISSN 0022-1694
Groundwater level measurements taken over a 4-year period from an extensive network of wells and boreholes within the HAPEX-Sahel (Hydrologic Atmospheric Pilot Experiment in the Sahel) degree square (south Niger), together with existing data, have provided an insight into infiltration and recharge processes taking place in the porous phreatic aquifer of the Continental Terminal formation. Despite high spatial and temporal variability of aquifer response to rainfall (rises of between 0 and 9 m are recorded), a pattern of recharge can be recognised. Aquifer responses vary from site to site, but the type of response at any single point tends to be consistent from year to year. Recharge is dominated by infiltration from temporary drainage networks (pools and streams) and aquifer response depends to a large extent on aquifer hydraulic characteristics and distance from the nearest infiltrating zone. In many wells, for which data extending back to 1987 is available, water levels show a consistent year by year rise. This is interpreted as a process of aquifer recovery following the severe drought of the 1970s and early 1980s, though part may also be attributable to changing patterns of land management (e.g. woodland clearance). Initial estimates of regional recharge are from 50-60 mm/y, or in other words about 10% of annual rainfall. The figure is supported by other methods of investigation (hydrochemical analyses ; water budgets of pools). (Résumé d'auteur)
Plan de classement
Dynamique de l'eau à l'interface sol-plante-atmosphère [062MECEAU02]
Descripteurs
BILAN HYDROLOGIQUE ; AQUIFERE ; ECOULEMENT SOUTERRAIN ; INFILTRATION ; VARIATION SPATIALE ; VARIATION TEMPORELLE
Description Géographique
NIGER ; ZONE SEMIARIDE
Localisation
Fonds IRD [F B010010997]
Identifiant IRD
fdi:010010997
