期刊名称：Science et changements planétaires / Sécheresse
印刷版ISSN：1147-7806
电子版ISSN：1777-5922
出版年度：2010
卷号：21
期号：2
页码：97-104
DOI：10.1684/sec.2010.0237
出版社：John Libbey Eurotext
摘要：Figures See all figures Authors Lazar AA Aguiar , Michelle Garneau , Anne-Marie Lézine , Pascal Maugis Université du Québec à Montréal GEOTOP-UQAM-Mc Gill 201 Président-Kennedy H2X 3Y7 Montréal Canada, CNRS-LSCECEA-Orme des Merisiers Bâtiment 701 91191 Gif-sur-Yvette France Key words: anthropic factor, climate, ground water, hydrogeology, rainfall, Senegal DOI : 10.1684/sec.2010.0237 Page(s) : 97-104 Published in: 2010 The main objective of this study is to examine the variability of groundwater level over the past 50 years in the Niayes region of Senegal and identify possible links with the climate and human activities. The analysis of the water table morphology from multi-temporal piezometric maps shows that the biggest piezometric depletions were recorded in the 1970's and 1980's with a gradual decline averaging almost −0.51m every ten years. At the intra-annual scale, the piezometric variations are more substantial at the end of the rainy season. The 1974 water balance analysis suggests that natural causes are the main water withdrawal factors with over 96% of water outlet among which 90% is lost through evapotranspiration. The water extracted for human activities represents no more than 4% of all water leaving the Niayes' water system. However, the evolution of the groundwater level is also controlled by human activities, mainly through hydraulic infrastructures (dams) in the northern sector of the Niayes where the water level fell by only 0.11 mm between 1984 and 1994, despite the continuing rainfall deficits of the 1980's and 1990's.
