carte webLocation of the coastal merjas of the Gharb plain (© Choukrani, 2018)




The development of the Gharb plain began at the beginning of the last century. In 1917, the engineer of Public Works Séjournet undertook sanitation works to dry up several wetlands (merjas) in order to alleviate catastrophic floods, and irrigation to produce in times of drought on these fertile swampy lands.






image1 web Merjas soil encroachments (© Choukrani, 2018)




Subsequently, the Sebou project contributed to the agricultural development of the Gharb plain through the construction of a system of flood protection dikes, dams regulating flows, and drainage for the sanitation of irrigated lands. However, floods continue to damage large areas of agricultural land and endanger human lives, as witnessed by the 100-year flood of 2010.


image3 web Gravity irrigation of sunflower in merjas (© Choukrani, 2018)


This flooding revealed the dual role of merjas: a protective role of farming and urban areas during floods through their ability to regulate water level variations, and a productive role when they are cropped by local populations or grazed as pasture after floodwater recedes.


image2 web Removal of Merja soils (© Choukrani, 2018)








This work aims to answer three main questions:

  • What are the ecosystem services provided by the merjas in the Gharb Plain?
  • What are the hydraulic and agricultural links and interactions between these merjas and all the components of their environment (the hydrographic network, the sanitation and drainage network, the groundwater table, the hydroagricultural zones developed (e. g. dune ranges, inland dunes, etc.))?
  • To what extent could the development of merjas adapt to their very nature (e.g. "nature-based solution") and to the context of the Gharb plain subject to global change (i.e. climate, demographic, economic)?



image4 web   image5 web
Merja Ras Daoura (coastal merja) - (© Choukrani, 2018)
Merja Sidi Mohammed Benmansour (coastal merja) - (© Choukrani, 2018)


Key words: Merja, floodplains, wetlands, ecosystem services, Nature-based solutions, ecological engineering

Drip irrigation is considered the best technique to save water in agriculture. However clogging of drippers is the main cause of loss of water efficiency, especially for small farmers involved in a modernization process. This can be caused by physical, chemical or biological factors, individually or combined. These phenomena will be increased when treated wastewater is reused in irrigation. On agricultural field, with the exception of visible symptoms on crops, the decrease of the dripper efficiency is a challenge to detect. This becomes impossible in the case of buried installations in the soil. The thesis project aims to enhance our knowledge of fouling mechanisms and the development of innovative detection methodology for the dripper clogging using spectrometry method.

The first step will concern the quantification (kinetics) and qualification (composition) of physical, chemical and biological fouling by optical methods according to the irrigation water qualities (particle concentration or treated wastewater). In the second step, the method which presents the best opportunities will retained in order to develop the proof concept of fouling sensor adapted to the irrigation context.





There is no translation available.

Le projet d’économie et de valorisation de l’eau d’irrigation dans le périmètre du Gharb s’inscrit dans le cadre du Plan Maroc Vert et notamment sa composante relative au Programme National d’Économie l’Eau en Irrigation (PNEEI). Il est mis en œuvre par l’Office Régional de Mise en Valeur Agricole du Gharb (ORMVAG). Il vise l’économie et la valorisation de l’eau en irrigation sur une surface de 81700 ha dont 42300 ha en projet de reconversion collective.

Au Gharb, le choix s’est prioritairement porté sur la reconversion du système par aspersion en irrigation localisée dont les avantages en termes d’économie d’eau, d’intrants et de forces de travail sont largement reconnus, mais qui présentent des exigences techniques et financières importantes et ce à plusieurs niveaux de leur utilisation.


Les projets de reconversion collective, en comparaison avec les projets de reconversion individuelle, nécessitent un investissement énorme et impliquent un certain nombre de défis à relever pour garantir leur réussite, notamment quant à l’adaptation des agriculteurs ayant affaire à une nouvelle technique d’irrigation qui nécessite un changement important des pratiques d’irrigation et des systèmes de cultures pratiqués.


La transition entre l’aspersion et le GàG prendra du temps et le réseau d’irrigation fonctionnera sous les deux systèmes pendant une certaine période.


Ce travail portera sur l’analyse du fonctionnement simultané d’un système collectif sous irrigation à la demande par aspersion et irrigation localisée, et cela à travers d’enquêtes de terrain, d’expertise, d’expérimentation sur le terrain dans le contexte réel des agriculteurs et de modélisation.


IMG 20180604 kettani 
 © KASHI Fouzia : Mesure de pression au niveau d’une rampe sous irrigation en goutte à goutte






The aim of the SmartFertiReuse project is to develop a complete and innovative service to support both the agricultural world and local authorities in the recovery of treated wastewater and the optimal management of fertilisers. The service will range from the design of an operational system to its deployment and management at the plot scale, i.e. from the production and distribution of water, the adjustment of irrigation to the needs of the plants, to monitoring and quality control of the irrigation water).

The other objective of the project is to develop and implement  an industrial scale steering tool for the irrigation of agricultural plots. This will be an intelligent tool dedicated to sprinkler irrigation of field crops to deliver water of controlled quality that meets the nutrient requirements (mainly nitrogen) of the target crop, depending on the quality of the water leaving the wastewater treatment plant. The sectors developed and run by this intelligent fertilization management system will make it possible to supplement irrigation water with missing mineral nutrients, depending on the composition of the treated wastewater and the needs of the particular. The system will be automated and will include innovative interconnected sensors and will be driven by calibrated algorithms sold with the system.




There is no translation available.

L’irrigation agricole mobilise plus de 70% des ressources en eau douce à travers le monde : l’usage parcimonieux de cette eau constitue un enjeu majeur en France et à l’international. Le modèle Optirrig développé par Irstea vise à la génération, l'analyse et l'optimisation de scénarios d'irrigation des cultures. Il s'appuie sur une description simplifiée de la croissance des plantes en fonction de l'évolution des ressources en eau et en azote du sol, avec l'idée qu'identifier les bonnes stratégies d'irrigation et de fertilisation importe plus que décrire en détail les processus biophysiques en jeu, pour des objectifs opérationnels à l'échelle de la parcelle, de l'exploitation ou du territoire.

Oases and arid regions of the Maghreb are facing major social changes, e.g., the increase in mobilities. These changes concern also the agricultural sector, as capital-intensive forms of agriculture develop alongside more traditional ones. These changes are source of development opportunities, but also of risks in terms of the sustainability of such development, for instance the non-sustainable use of soils and water, the decrease of biodiversity, and increased social inequalities.

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