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Considering groundwater use to improve the assessment of groundwater pumping for irrigation in North Africa | Prendre en compte l’utilisation des eaux souterraines pour améliorer l’évaluation des pompages d’eaux souterraines pour l’irrigation dans le Nord de l’Afrique Consideraciones del uso del agua subterránea para mejorar la evaluación del bombeo de agua subterránea para el riego en el norte de África 考虑地下水的利用情况来提高北非地区抽取地下水用于灌溉的评价水平 Considerando o uso das águas subterrâneas para melhorar a avaliação do bombeamento de água subterrânea para irrigação no Norte de África Texte intégral
2017
Massuel, Sylvain | Amichi, Farida | Ameur, Fatah | Calvez, Roger | Jenhaoui, Zakia | Bouarfa, Sami | Kuper, Marcel | Habaieb, Hamadi | Hartani, Tarik | Hammani, Ali
Groundwater resources in semi-arid areas and especially in the Mediterranean face a growing demand for irrigated agriculture and, to a lesser extent, for domestic uses. Consequently, groundwater reserves are affected and water-table drops are widely observed. This leads to strong constraints on groundwater access for farmers, while managers worry about the future evolution of the water resources. A common problem for building proper groundwater management plans is the difficulty in assessing individual groundwater withdrawals at regional scale. Predicting future trends of these groundwater withdrawals is even more challenging. The basic question is how to assess the water budget variables and their evolution when they are deeply linked to human activities, themselves driven by countless factors (access to natural resources, public policies, market, etc.). This study provides some possible answers by focusing on the assessment of groundwater withdrawals for irrigated agriculture at three sites in North Africa (Morocco, Tunisia and Algeria). Efforts were made to understand the different features that influence irrigation practices, and an adaptive user-oriented methodology was used to monitor groundwater withdrawals. For each site, different key factors affecting the regional groundwater abstraction and its past evolution were identified by involving farmers’ knowledge. Factors such as farmer access to land and groundwater or development of public infrastructures (electrical distribution network) are crucial to decode the results of well inventories and assess the regional groundwater abstraction and its future trend. This leads one to look with caution at the number of wells cited in the literature, which could be oversimplified.
Afficher plus [+] Moins [-]Specifying the differentiated contribution of farmers to groundwater depletion in two irrigated areas in North Africa | Caractérisation de la contribution différentiée des agriculteurs à l’épuisement des eaux souterraines dans deux zones irriguées en Afrique du Nord Especificación de la contribución diferenciada de los agricultores en el agotamiento del agua subterránea en dos zonas de riego en el norte de África 具体说明北非两个灌溉区农民对地下水消耗的分化型分布 Especificando a contribuição diferenciada de agricultores para a depleção das águas subterrâneas em duas áreas irrigadas no Norte da África Texte intégral
2017
Ameur, Fatah | Amichi, Hichem | Kuper, Marcel | Hammani, Ali
Much attention has been paid to the issue of groundwater depletion linked to intensive groundwater-based agriculture in (semi-)arid areas. Often referred to as the “overexploitation” of aquifers, groundwater depletion is generally attributed to the entire agricultural sector without distinguishing between different uses and users. Although it expresses a general concern for future users, the ambiguous term of “overexploitation” does not acknowledge the contested nature of groundwater use and emerging inequalities. Also, the impact of inequality on groundwater depletion is rarely questioned. The aim of this article is to investigate how and by whom groundwater is depleted, and in turn, how unequal access to groundwater fuels the socioeconomic differentiation of farms and groundwater depletion. Based on a detailed analysis of groundwater use from a user perspective in two irrigated areas in North Africa (Morocco and Algeria), this study shows how the context of groundwater depletion exacerbates—and is exacerbated by—existing inequalities. The paper concludes that knowing how much is withdrawn, where, and by whom provides helpful information for more informed groundwater management by a better understanding of the response of users to declining groundwater conditions and the interests and incentives of different social categories of famers to contribute to groundwater management.
Afficher plus [+] Moins [-]Can agricultural groundwater economies collapse? An inquiry into the pathways of four groundwater economies under threat | Les économies agricoles reposant sur l’eau souterraine peuvent-elles s’effondrer ? Une enquête sur les trajectoires de quatre économies basées sur l’eau souterraine menacées ¿Pueden colapsar las economías agrícolas a base de aguas subterráneas? Una investigación sobre las trayectorias bajo amenaza de cuatro economías de agua subterránea 农业地下水经济体能崩溃吗?处于威胁之下的四种地下水经济途径探究 A economia agrícola baseada nas águas subterrâneas pode colapsar? Uma investigação nos caminhos de quatro casos sob ameaça Texte intégral
2017
Petit, Olivier | Kuper, Marcel | López-Gunn, Elena | Rinaudo, Jean-Daniel | Daoudi, Ali | Lejars, Caroline
The aim of this paper is to investigate the notion of collapse of agricultural groundwater economies using the adaptive-cycle analytical framework. This framework was applied to four case studies in southern Europe and North Africa to question and discuss the dynamics of agricultural groundwater economies. In two case studies (Saiss in Morocco and Clain basin in France), the imminent physical or socio-economic collapse was a major concern for stakeholders and the early signs of collapse led to re-organization of the groundwater economy. In the other two cases (Biskra in Algeria and Almeria in Spain), collapse was either not yet a concern or had been temporarily resolved through increased efficiency and access to additional water resources. This comparative analysis shows the importance of taking the early signs of collapse into account. These signs can be either related to resource depletion or to environmental and socio-economic impacts. Beyond these four case studies, the large number of groundwater economies under threat in (semi-)arid areas should present a warning regarding their possible collapse. Collapse can have severe and irreversible consequences in some cases, but it can also mean new opportunities and changes.
Afficher plus [+] Moins [-]Impact of groundwater flow across tectonic aquifer compartments in a Miocene sandstone aquifer: three-dimensional hydrogeological modeling of the Kasserine aquifer system in central Tunisia and northeastern Algeria | Impact de l’écoulement des eaux souterraines dans les compartiments tectoniques aquifères de l’aquifère gréseux du Miocène: modélisation hydrogéologique en 3D du système aquifère de Kasserine dans la partie centrale de la Tunisie et du nord-est de l’Algérie Impacto del flujo de agua subterránea a través de compartimientos tectónicos en un acuífero de arenisca del Mioceno: modelado hidrogeológico tridimensional del Sistema de Acuíferos Kasserine en el centro de Túnez y el noreste de Argelia 中新世砂岩含水层中穿过构造含水层隔间的地下水流影响:突尼斯中部和阿尔及利亚东北部Kasserine含水层三维水文地质建模 Impacto do fluxo das águas subterrâneas através de compartimentos tectônicos de um aquífero arenítico miocênico: modelagem hidrogeológica tridimensional do Sistema Aquífero Kasserine na Tunísia central e nordeste da Argélia Texte intégral
2019
Hassen, Imen | Milnes, Ellen | Gibson, Helen | Bouhlila, Rachida
The Kasserine Aquifer System (KAS) is a transboundary aquifer, located in an arid region in central Tunisia and extending into northeastern Algeria. The system consists of four compartments: Oum Ali-Thelepte, Feriana-Skhirat, and the Plateau and the Plaine of Kasserine. The challenge of this study was to evaluate the influence of regional faults on groundwater flow in the different compartments of the KAS and to estimate the regional impact of current and future groundwater use. A three-dimensional saturated regional groundwater flow model for the steady state and transient conditions (1980–2015) was created and calibrated. This work was achieved using numerical flow modelling, coupled with geological modelling, using FEFLOW and GeoModeller software. The significance of regional faults as potential barriers or conduits to groundwater flow in the different aquifer compartments was evaluated by considering the different recharge rates. Two connectivity hypotheses were proposed at each major fault, and the general hydraulic relationship of units that are juxtaposed by each fault were considered. This study contributes rigorous estimates for the diffuse and concentrated recharge in the arid study region, and evaluates the groundwater behavior that shows a gradual decline in the water table over time, using a regional model. Different predicted outcomes for the KAS based on variable potential groundwater extraction scenarios for the period 2015–2050 have been developed. The results of numerical simulation provide useful information regarding the behavior of the KAS aquifers, and contribute significant knowledge to guide sustainable practice for present and future groundwater management.
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