Rapid evolution of water resources in the Senegal delta

Autor: Jean-Luc Saos, Raymond Malou, Marc Leblanc, Christian Leduc, Fatou Diop Ngom, Sarah Tweed, Jean-Claude Bader
Přispěvatelé: Faculty of Sciences and Technique, Department of Geology, Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD), Gestion de l'Eau, Acteurs, Usages (UMR G-EAU), Institut de Recherche pour le Développement (IRD)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-AgroParisTech-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), AgroParisTech, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Centre for TropicalWater and Aquatic Ecosystem Research (TropWATER), School of Earth and Environmental Sciences [Australia], James Cook University (JCU)-James Cook University (JCU), Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Agence Nationale de la Recherche in France [ANR CHEX TERRA 12-007], Australian Research Council [DP110103364], Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)
Jazyk: angličtina
Rok vydání: 2016
Předmět:
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences
010504 meteorology & atmospheric sciences
Hydrological change
river
0208 environmental biotechnology
semi-arid
Water supply
Aquifer
02 engineering and technology
fonctionnement hydrologique
Environmental change
Oceanography
01 natural sciences
groundwater retroaction
irrigation
aménagement hydraulique
Senegal river
Semi-arid
River mouth
Groundwater retroaction
Water cycle
Irrigation
River regime
0105 earth and related environmental sciences
2. Zero hunger
Hydrology
Global and Planetary Change
geography
geography.geographical_feature_category
business.industry
Tidal irrigation
sénégal
environmental change
zone semi aride
Water development
semi-arid zone
6. Clean water
020801 environmental engineering
Water level
Water resources
13. Climate action
mauritanie
hydrological change
water development
Environmental science
business
management
fleuve sénégal
Zdroj: Global and Planetary Change
Global and Planetary Change, Elsevier, 2016, 144, pp.34-47. ⟨10.1016/j.gloplacha.2016.07.002⟩
ISSN: 0921-8181
Popis: In recent decades major water developments have led to an agricultural transformation of the Senegal delta both in Senegal and Mauritania. This otherwise, semi-arid region of the Sahel band now has an abundant supply of freshwater all year round mostly used for irrigation and urban water supply, including for the capital cities of the two countries. Archives from the Landsat satellites and in-situ hydrographs were used in this paper to retrace and analyse the hydrological changes that have taken place in the region since the middle of the 20th century. The satellite archives indicate that the area covered by irrigation increased by one order of magnitude from 73 km(2) in 1973 to similar to 770 km(2) in 2010. The observed hydrological changes are complex, multi-faceted and often of great magnitude. If the water cycle was representative of natural conditions in the early 1980s, it is now representative of a heavily modified system controlled and impacted by human activities. The first hydraulic infrastructure was installed in 1947 to enable the Lake of Guiers to become the main water supply for Dakar. Two large dams were built on the Senegal River in the mid-1980s that modified the hydrological regime of the river by 1) preventing seawater intrusion, 2) raising the stage of the river and-of Lake of Guiers and 3) moderating floods. Another recent hydrological change in the delta was the opening of river mouth in 2003, which has led to a reduction of the average water level while increasing the semi-diurnal tidal wave between the river mouth and Diama. Each phase of these river regime changes and each step of the irrigation expansion are expressed in localised changes in the physical groundwater system. Increasingly, the retroaction from the shallow aquifer systems is observed as a rise of the saline water table. This poses a threat to the environmental and agricultural value of the region, and the salinization of the soils. Mitigating actions for this threat are currently being envisaged by the authorities.
Databáze: OpenAIRE
Externí odkaz: