Seasonal Variations of the Depletion Factor during Recession Periods in the Senegal, Gambia and Niger Watersheds
Author:
Bader Jean-Claude,Dacosta Honoré,Pouget Jean-Christophe
Abstract
The daily depletion factor K describes the discharge decrease of rivers only fed by groundwater in the absence of rainfall. In the Senegal, Gambia and Niger river basins in West Africa, the flow recession can exceed 6 months and the precise knowledge of K thus allows discharge forecasts to be made over several months, and is hence potentially interesting for hydraulic structure managers. Seasonal flow recession observed at 54 gauging stations in these basins from 1950 to 2016 is represented by empirical and usual conceptual models that express K. Compared to conventional conceptual models, an empirical model representing K as a polynomial of the decimal logarithm of discharge Q gives better representations of K and better discharge forecasting at horizons from 1 to 120 days for most stations. The relationship between specific discharge Qs and K, not monotonous, is highly homogeneous in some sub-basins but differs significantly between the Senegal and Gambia basins on the one hand and the Niger basin on the other. The relationship K(Q) evolves slightly between three successive periods, with values of K generally lower (meaning faster discharge decrease) in the intermediate period centered on the years 1970–1980. These climate-related interannual variations are much smaller than the seasonal variations of K.
Subject
Water Science and Technology,Aquatic Science,Geography, Planning and Development,Biochemistry
Reference49 articles.
1. Hydrologie de Surface;Roche,1963
2. Base-Flow Recessions-A Review
3. A review of baseflow recession analysis
4. Recherches théoriques sur l’écoulement des nappes d’eau infiltrées dans le sol et sur le débit des sources;Boussinesq;J. Math. Pure Appl.,1904
5. Etiages et Tarissements: Vers Quelles Modélisations ? L’approche Conceptuelle et L’analyse Statistique en Réponse à la Diversité Spatiale des Ecoulements en Etiage des Cours d’eau de l’Est Français;Lang,2007
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