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Hydrogeology Journal

, Volume 27, Issue 3, pp 929–943 | Cite as

Review: Groundwater recharge estimation in arid and semi-arid southern Africa

  • Yongxin XuEmail author
  • Hans E. Beekman
Paper
  • 721 Downloads

Abstract

Groundwater recharge estimation in arid and semi-arid southern Africa is reviewed based on four decades of recharge investigation in the region. This paper updates an earlier review by incorporating emerging and grey literature from a wide range of research sectors in southern Africa, collected during the past decade. For ease of comparison, methods commonly used are critically reviewed with a rating provided in terms of accuracy, application and costs. These include, but are not limited to, the methods of chloride mass balance (CMB), rainfall infiltration breakthrough (RIB), Extended model for Aquifer Recharge and moisture Transport through unsaturated Hardrock (EARTH), water-table fluctuation (WTF), water balance in the saturated zone (including equal volume spring flow (EVSF) and saturated volume fluctuation (SVF)), and groundwater modelling (GM). As the methods based on mass balance and relationships between rainfall, water-level fluctuations and abstraction are proven to have the potential to simulate and forecast groundwater recharge, the EVSF and CMB methods are highly recommended for use in the southern African region according to this review. Caution on the uncertainty associated with error input and propagation for all the methods is advised, based on a case study in South Africa. The review provides an updated source of references related to recharge estimation in arid and semi-arid regions of Sub-Saharan Africa in general and to ongoing projects for the implementation for Resource Directed Measures (part of the National Water Resources Strategy) in South Africa in particular.

Keywords

Arid regions Groundwater recharge/water budget Estimation methods South Africa Sub-Saharan Africa 

Revue: Évaluation de la recharge drecharge des eaux souterraines en Afrique australe aride et semi-aride

Résumé

L’évaluation de la recharge des eaux souterraines en Afrique australe aride et semi-aride est. passée en revue sur la base de quatre décennies de recherche sur la recharge dans la région. Cet article met à jour une revue précédente en incorporant de la littérature émergente et de la littérature grise provenant d’une large gamme de travaux de recherches en Afrique australe, rassemblés pendant la décennie passée. Pour faciliter la comparaison, les méthodes généralement utilisées sont passées en revue de manière critique à l’aide d’une estimation produite en termes d’exactitude, application et coûts. Celles-ci incluent, sans s’y limiter, le bilan des chlorures (CMB), le développement Pluie-Infiltration (RIB), le modèle étendu pour la recharge de l’aquifère et le transport de l’humidité à travers la zone non saturée des roches de socle (EARTH), l’analyse des fluctuations de nappe (WTF), le bilan hydrologique dans la zone saturée (y compris l’équivalence volumique au débit des sources (EVSF), la fluctuation du volume saturé (SVF), ainsi que la modélisation des eaux souterraines (GM). Comme il s’avère que les méthodes basées sur le bilan massique et les rapports entre les précipitations, les fluctuations de niveau d’eau et les prélèvements ont le potentiel de simuler et de prévoir la recharge d’eaux souterraines, les méthodes d’EVSF et de CMB sont fortement recommandées pour être utilisées dans la région de l’Afrique australe, selon cette revue. La prudence sur l’incertitude liée à l’entrée et à la propagation d’erreur pour toutes les méthodes est. conseillée, selon une étude de cas en Afrique du Sud. La revue fournit une source actualisée de références concernant l’évaluation de la recharge dans des régions arides et semi-arides de l’Afrique sub-saharienne en général et, les projets en cours pour l’exécution du programme Mesures Axées sur la Ressource (élément de la stratégie nationale des ressources en eau) en Afrique du Sud en particulier.

Revisión: Estimación de la recarga de agua subterránea en el África austral árida y semiáridaárida

Resumen

Se analiza la estimación de la recarga de agua subterránea en el África austral árida y semiárida sobre la base de cuatro décadas de investigación en la región. Este documento actualiza una revisión anterior incorporando literatura emergente e inédita de una amplia gama de sectores de investigación en el sur de África, recopilados durante la última década. Para facilitar la comparación, los métodos comúnmente utilizados se analizar críticamente con una calificación proporcionada en términos de precisión, aplicación y costos. Estos incluyen, pero no se limitan a, los métodos de Balance de Masa de Cloruro (CMB), de infiltración de la precipitación (RIB), del modelo EARTHH (modelo extendido para recarga de acuífero y transporte de humedad a través de la zona no saturada, de la fluctuación de niveles freáticos (WTF), del equilibrio de agua en la zona saturada (incluido el flujo de manantiales de igual volumen (EVSF) y de la fluctuación de volumen saturado (SVF)) y del modelado de aguas subterráneas (GM). Como los métodos basados ​​en el balance de masa y las relaciones entre lluvia, fluctuaciones del nivel del agua y extracción han demostrado tener el potencial de simular y pronosticar la recarga de aguas subterráneas, los métodos EVSF y CMB son altamente recomendables para su uso en la región del sur de África según esta revisión. Se recomienda precaución sobre la incertidumbre asociada con la entrada de error y la propagación para todos los métodos, según un estudio de caso en Sudáfrica. La revisión proporciona una fuente actualizada de referencias relacionadas con la estimación de la recarga en regiones áridas y semiáridas del África subsahariana en general y con proyectos en curso para la implementación de medidas dirigidas a los recursos (parte de la estrategia nacional de recursos hídricos) en especial en Sudáfrica.

综述:非洲南部干旱半干旱地区地下水补给量估算

摘要

根据四十年的补给调查,论述了非洲南部干旱半干旱地区地下水补给量估算情况。本文通过把过去十年在非洲南部各个部门收集到的新和老的文献结合在一起,对早先的综述进行了更新。为便于比较,根据准确性、应用情况和成本提供的等级对常用的方法进行了详尽的论述。这些方法包括、但不限于,氯化物质量平衡法、降雨入渗突破法、通过非饱和硬岩的含水层补给和水分运移的扩展模型法、水位波动法、饱和带水平衡法(等量容积泉水流法和饱和容积波动法)以及地下水模拟。由于这些基于质量平衡及降雨、水位波动和抽水之间的相互关系的方法证明具有模拟和预测地下水补给的潜力,因此,本文综述强烈建议在非洲南部采用等量容积泉水流法和氯化物质量平衡法。根据南非一个研究案例,特别提醒在所有方法中,要谨慎对待与错误输入和传播相关的不确定性。综述提供了与非洲撒哈拉以南干旱半干旱地区补给量估算有关的以及与南非正在进行的资源指导措施实施项目相关的最新参考源。

Revisão: Estimativa de recarga de águas subterrâneas na África austral árida e semiárida

Resumo

A estimativa de recarga de águas subterrâneas na África austral árida e semiárida é revisada com base em quatro décadas de investigação de recarga na região. Este artigo atualiza uma revisão anterior, incorporando literatura recente e passada de uma ampla gama de setores de pesquisa na África austral, coletados durante a última década. Para facilitar a comparação, os métodos comumente usados são revisados criticamente com uma classificação baseada em termos de precisão, aplicação e custos. Estes incluem, mas não estão limitados a, os métodos de Balanço de Massa de Cloreto (BMC/CBM), Ruptura da Infiltração da Precipitação (RIP/RIB), Modelo Estendido para Recarga de Aquífero e Transporte de Umidade através de Rocha Insaturada (EARTH), Variação da Superfície Livre (VSL/WTF), Balanço Hídrico na Zona Saturada (incluindo Fluxo de Fonte de Volume Igual (FFVI/EVSF) e Flutuação do Volume Saturado (FVS/SVF)) e Modelagem de Águas Subterrâneas (MAS). Como os métodos baseados em balanço de massa e relações entre chuvas, flutuações no nível da água e captação têm o potencial de simular e prever a recarga das águas subterrâneas, os métodos FFVI e BMC são altamente recomendados para uso na região da África austral de acordo com esta revisão. É aconselhável ter cuidado com a incerteza associada à entrada e propagação de erros para todos os métodos, com base em um estudo de caso na África do Sul. A revisão fornece uma fonte atualizada de referências relacionadas à estimativa de recarga em regiões áridas e semiáridas da África Subsaariana em geral e a projetos em andamento para a implementação de Medidas Dirigidas à Recursos (parte da Estratégia Nacional de Recursos Hídricos) na África do Sul em especial.

Notes

Acknowledgements

This paper builds upon a UNESCO publication by Beekman and Xu (2003). Grey literature, including reports, were provided by many groundwater practitioners including Diganta Sarma, Eddie van Wyk, Phil Hobbs and others. The College of Water Resources Science and Engineering at Taiyuan University of Technology in China is acknowledged for providing support.

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Earth SciencesUniversity of the Western CapeCape TownSouth Africa
  2. 2.Institute of Africa Water Resources and EnvironmentHebei University of EngineeringHandanChina
  3. 3.Water Resources Management ConsultantHoutbaySouth Africa

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