Water and agriculture documentary base

The development of intensive irrigated agriculture in arid California has inspired many governments and people around the world. In the paper, we show how 'California' as a social imaginary influenced North Africa’s irrigation policies. We trace the influence of this imaginary at two very different and critical junctures: in Morocco under the French Protectorate from the 1930s to the 1950s and in the contemporary Algerian Sahara. We argue that the influence of the 'California' imaginary persisted because of how it appeared to be the perfect embodiment of capitalist modernity while at the same time exhibiting two crucial sociopolitical ambiguities; the first ambiguity concerned the proper role of the state and the second had to do with the California imaginary’s overall implications in terms of social equity. These ambiguities enabled governing actors to naturalise and routinise this imported imaginary even as they used it to forge distinct types of political settlements that were in line with local historical circumstances. We thus argue that the notion of imaginary, inherently visual and polysemic, is usefully distinguished from alternative notions such as paradigms, narratives and frames. We also contend that imaginaries do not function independently from other social forces, but rather that they are embedded in the wider political economy. This leads us to conclude that any transformation of agricultural policies in North Africa will require the diffusion of an alternative imaginary that is as effective in forging powerful social coalitions as the Californian dream proved to be.

Groundwater is essential for early-season agriculture in many arid regions. In such regions, however,
groundwater recharge is generally low, leading to groundwater degradation. State responses are seldom effective in addressing this issue, which leads to fatalist narratives of the unsustainability of profitable agricultural growth and the collapse of aquifers. We argue that such narratives make it difficult to recognise more promising instances in which communities find solutions to groundwater degradation. We call for a fine-grained analysis of the social practices around the use of groundwater, which, we argue, represent a process of commoning. We do so while recognising that the collective action of communities is embedded in an intricate set of relations with other stakeholders including the state, and that the positive environmental and transformative social change that is often associated with commoning cannot be taken for granted at the outset. Building on the case of the arid Drâa Valley in Morocco where watermelon production has expanded rapidly, we illustrate how the process of commoning evolves through different social practices, including: 1) the use of new farming practices that reveal the potential of the aquifer; 2) the representation of the aquifer as severely degraded and the development of a narrative around
it being a collective good to be protected against outsiders; 3) the defining and negotiating of rules to control groundwater access and use; and 4) the engagement in negotiations and the resolving of conflicts. Our analysis shows that commoning, as performed by young local farmers, is about extending the lifespan of the aquifer for agricultural production rather than preserving it indefinitely; however, an examination of commoning practices also reveals the capacity of the community to change the course of the future.

Immergés en hiver, les marais saisonniers (merjas) de la plaine du Gharb au Maroc étaient traditionnellement exploités pour le pâturage en été, à côté d’autres usages productifs. Pourtant, ils étaient considérés par l’administration coloniale comme des milieux insalubres et peu valorisés, malgré leur abondance en ressources naturelles. Au cours du XXe siècle, la plaine a fait l’objet d’un aménagement hydro-agricole, incorporant les merjas, pour contribuer aux objectifs nationaux de sécurité alimentaire et d’exportation de produits agricoles. Cet article interroge le regard porté par les acteurs locaux et institutionnels sur les merjas et les bénéfices qu’elles procurent, à travers une analyse des services écosystémiques. Si les institutions les considèrent comme des terres vierges à aménager et des zones tampon
de régulation des crues pour protéger les secteurs aménagés et les villes, les collectivités riveraines les considèrent comme des espaces productifs, défavorisés par les crues. L’étude montre des visions contrastées des services écosystémiques, où chaque acteur a une vision utilitariste des merjas. Malgré le débat international sur la biodiversité et le stockage de carbone dans les zones humides, les dimensions
écologiques sont peu citées. L’approche par les services écosystémiques dévoile les antagonismes entre acteurs, mais peut être un moyen de négociation sur le devenir des merjas dans une vision territoriale

El cambio de uso de suelo en las cuencas tiene implicaciones en la pérdida de suelo y en el incremento de la escorrentía superficial. El objetivo del presente estudio fue evaluar los efectos en la erosión hídrica y el hidrograma de crecidas por del cambio del uso del suelo en la microcuenca del río Puca. Se aplico el modelo RUSLE con el uso de SIG para la estimación de la erosión hídrica y el modelo hidrológico HEC-HMS para la generación de hidrogramas de crecida para periodos de retorno de 25, 50 y 100 años. Para conocer el comportamiento de la escorrentía por el cambio del uso del suelo se establecieron tres escenarios con diferentes periodos de retorno (TR). De acuerdo con el uso de suelo del año 2016, el 17, 33, 34 y 16% de la superficie total (224.06 km2) de la microcuenca, presenta un nivel de erosión normal, ligero, moderado y severo, respectivamente. La pérdida promedio de suelo es de 7.4 t ha-1año-1 y la cantidad de sedimentos que llega al cauce del río Puca es de 0.8 t ha-1año-1. Los hidrogramas de crecida para periodos de retorno de 25, 50 y 100 años genera caudales máximos de 364.9, 422.2, y 531.5 m3/s, respectivamente. Los tres escenarios para TR de 25, 50 y 100 años generaron nueve hidrogramas de crecida, los máximos caudales fueron incrementándose según el progresivo cambio de uso del suelo. En el escenario 2 para un TR de 50 años se genera el desbordamiento del río Puca en el punto de salida de la microcuenca. El cambio de uso de suelo genera la pérdida del suelo (erosión hídrica), sedimentación del río Puca y cambios en la respuesta hidrológica (hidrogramas de crecida) de la microcuenca.

As in many tropical deltas globally, annual floods shape the livelihoods of the largely rural population in the Cambodian Mekong delta. Agricultural cycles are keyed to the flood arrival, peak, and recession, and fish populations depend on inundated floodplains for their regeneration. However, as factors like climate change and hydropower infrastructure development are altering the Mekong’s hydrology, the inundation dynamics of its deltaic floodplains are shifting as well. Several studies have assessed the general changes of river discharge and
flood extent on a basin- or delta-wide scale. Yet the sustainable development of this region is relying on dynamics at more local and specific scales, which have not been addressed so far. This paper presents a methodology to track the evolution of hydrological regimes and associated inundations in tropical deltas such as the upper Mekong delta in Cambodia, where it is applied over the past 30 years. Data
scarcity and heterogeneity of the environment in this region necessitated the use of combined approaches. We established a link between water levels measured in situ and flood maps derived from optical and radar satellite images (Sentinel-1 and − 2).The robustness of the link was assessed using Sentinel, Landsat imagery and the TanDEM-X (12 m) elevation model. This water level-flood link (WAFL) was then used to reconstruct a daily time series of inundation extents reaching back to the beginning of hydrological measurements in 1991 (30 years). On
this basis, changes in the incidence, duration, and spatial distribution of floods were analysed. The results indicated that WAFL can be used to reconstruct inundation maps with an overall robustness of 87% in comparison to historical inundation maps derived from remote sensing imagery. Comparisons of WAFLderived flood extents with Landsat images further underscored the significant role of local infrastructure, sedimentation dynamics, and land cover to explain changes in inundation dynamics. WAFL-based analyses revealed that inundation durations have decreased by an average of 19 days when comparing the periods before and after 2008, which was identified as a break point in the hydrological time series. Furthermore, a drastic decrease in inundation the annual frequency with which individual pixels are flooded can be detected during the first half of the traditional flood season, with an average of − 21% in early August, negatively impacting water-based livelihoods, from agriculture to fisheries.