Land clearing, climate variability, and water resources increase in semiarid southwest Niger: A review
Guillaume Favreau,B. Cappelaere,Sylvain Massuel,Marc Leblanc,Marie Boucher,Nicolas Boulain,Christian Leduc +6 more
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TLDR
In this article, a physically-based, distributed hydrological model showed that land clearing increased runoff threefold, whereas the rainfall deficit decreased runoff by a factor of 2, and that the indirect impacts of land use change on water quantity and quality are much greater than the direct influence of climate variability.Abstract:
increases aquifer recharge. At the local scale (2 km 2 ), a physically based, distributed hydrological model showed that land clearing increased runoff threefold, whereas the rainfall deficit decreased runoff by a factor of 2. At a larger scale (500 km 2 , 1950–1992 period), historical aerial photographs showed a 2.5-fold increase in the density of gullies, in response to an 80% decrease in perennial vegetation. At the scale of the entire study area (5000 km 2 ), analytical modeling of groundwater radioisotope data ( 3 H and 14 C) showed that the recharge rate prior to land clearing (1950s) was about 2 mm a � 1 ; postclearing recharge, estimated from groundwater level fluctuations and constrained by subsurface geophysical surveys, was estimated to be 25 ± 7 mm a � 1 . This order of magnitude increase in groundwater fluxes has also impacted groundwater quality near ponds, as shown by a rising trend in groundwater nitrate concentrations of natural origin (75% of d 15 N values in the range +4 to +8%). In this well-documented region of semiarid Africa, the indirect impacts of land use change on water quantity and quality are much greater than the direct influence of climate variability.read more
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Journal ArticleDOI
Ground water and climate change
Richard G. Taylor,Bridget R. Scanlon,Petra Döll,Matthew Rodell,Rens van Beek,Yoshihide Wada,Laurent Longuevergne,Marc Leblanc,James S. Famiglietti,Mike Edmunds,Leonard F. Konikow,Timothy R. Green,Jianyao Chen,Makoto Taniguchi,Marc F. P. Bierkens,Alan MacDonald,Ying Fan,Reed M. Maxwell,Yossi Yechieli,Jason J. Gurdak,Diana M. Allen,Mohammad Shamsudduha,Kevin M. Hiscock,Pat J.-F. Yeh,Ian P. Holman,Holger Treidel +25 more
TL;DR: In this paper, the authors critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system, and highlight the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies.
MonographDOI
Estimating groundwater recharge
TL;DR: In this article, a critical evaluation of the theory and assumptions that underlie methods for estimating rates of groundwater recharge is provided, with detailed explanations of the methods provided - allowing readers to apply many of the techniques themselves without needing to consult additional references.
Book ChapterDOI
Woody Plant Encroachment: Causes and Consequences
Steven R. Archer,Erik M. Andersen,Katharine I. Predick,Susanne Schwinning,Robert J. Steidl,Steven R. Woods +5 more
TL;DR: In this article, the authors review the process of woody plant encroachment and its causes, the consequences for ecosystem function and the provision of services, and the effectiveness of management interventions aimed at reducing woody cover.
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Evidence of the dependence of groundwater resources on extreme rainfall in East Africa
Richard G. Taylor,Martin C. Todd,Lister Kongola,Louise Maurice,Emmanuel Nahozya,Hosea Sanga,Alan MacDonald +6 more
TL;DR: A 55-year record of groundwater-level observations in an aquifer in central Tanzania reveals the highly episodic occurrence of recharge resulting from anomalously intense seasonal rainfall as discussed by the authors, suggesting it may be a viable adaptation water source in the future.
Journal ArticleDOI
A review of historic and future hydrological changes in the Murray-Darling Basin
TL;DR: In this paper, a long-term time series of climate, hydrological and environmental data are used to analyze how compounding stresses have gradually affected the hydrologogical system and its services.
References
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