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Accueil du site → Doctorat → Espagne → 2012 → Diagnóstico comparativo del funcionamiento y la productividad del regadío en el Valle del rio Senegal en mauritania.Opciones de mejora

Universidad de Córdoba (2012)

Diagnóstico comparativo del funcionamiento y la productividad del regadío en el Valle del rio Senegal en mauritania.Opciones de mejora

Borgia, Cecilia

Titre : Diagnóstico comparativo del funcionamiento y la productividad del regadío en el Valle del rio Senegal en mauritania.Opciones de mejora

Comparative diagnosis of irrigation performance and productivity along the Senegal Valley in Mauritania.Opportunities for improvement

Auteur : Borgia, Cecilia

Université de soutenance : Universidad de Córdoba

Grade : Doctor of Philosophy (PhD) 2012

Résumé partiel
In the last fifty years, concerted efforts have been spent on improving irrigation technology and management, both in academic and professional circles. Despite all this, irrigation has failed to keep up with projected results. Understanding of causes and processes behind this poor performance is needed, especially in regions like the Sahel, where irrigation could play a fundamental role for food security and livelihoods. This research deepens into the causes of low productivity and abandonment of rice-based irrigated agriculture in the Senegal River valley in Mauritania. Performance assessment and benchmarking are means by which it is possible to analyse and compare water management practices within and across irrigation schemes while identifying measures to improve irrigation delivery service and resources use. Four were the specific objectives of this study. First, to evaluate the performance and variability in productivity and input use of a number of small- and large-scale irrigation schemes. Second, to study patterns of spatial variability of land productivity and water use in large irrigation schemes. Third, to establish benchmarks for productivity and performance that shall serve as reference for the improvement of irrigation schemes. Fourth, to draft concrete and fundamental propositions on what irrigation models are most appropriate for the conditions in Mauritania and how to steer future policy actions consequently. Rapid appraisal process (RAP) and benchmarking techniques allowed systematic compilation of technical, organisational, institutional, and financial information. Data collected during repetitious field visits, semi-structured interviews, and direct measurements constituted the basis for the calculation of external and internal irrigation performance indicators used in the comparative analysis of the irrigation schemes. The indicators used were : irrigation intensity, water delivery capacity, relative irrigation supply, land productivity, water productivity, energy productivity, equity, reliability, flexibility, adequacy, and efficiency. Rice production was measured in a representative sample of plots in each studied irrigation scheme. Water use was quantified based on flow rate measurements and records of pumping time. Benchmarking was based on hierarchical cluster (HCA) and data envelopment (DEA) analyses that allowed, respectively, grouping and ranking of irrigation schemes according to a set of indicators previously obtained from the performance assessment. Benchmarking of small and large schemes showed that land productivity and technical efficiency were highly variable in irrigation schemes along the Senegal valley in Mauritania ; however, both DEA and HCA showed that there were some productive and efficient schemes. DEA also identified the particular efficient schemes that should be taken as reference for improvement of each inefficient scheme. Performance assessment indicated that the state of the infrastructure and irrigation management are key factors in determining the variability of productivity and efficiency. Drainage turned out to have a greater influence than irrigation in determining intra-scheme spatial variability of yield and irrigation intensity in large schemes. Comparison of small- and large-scale irrigation schemes showed that, on a pure technical basis, large schemes did not perform worse than small schemes. However, small schemes showed greater variability, which may indicate a larger margin for improvement and also existence of successful schemes. The analysis of strengths and weaknesses of alternative irrigation models in Mauritania and their future perspectives for food security indicated that both large- and small-scale rice schemes are caught in a process known as “rehabilitation followed by deterioration trap” which must be reversed through the development of management capacity and physical upgrading of the irrigation infrastructure. Complete transfer of large schemes can only be pursued after extensive training, physical upgrading, and improved yields. The contribution of horticulture-based irrigation models to food security, poverty alleviation, and gender-equitable wealth creation lies in the development of a supportive environment of institutions and services for the autonomous replication of these systems. More research on the potential of private irrigation and agribusinesses, and related threats, is needed. Finally, sound policy planning and implementation requires updated national statistics that today are not available.

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Page publiée le 24 juin 2013, mise à jour le 8 février 2019