Portail HAL du CIHEAM Montpellier
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An operational framework for mapping irrigated areas at plot scale using Sentinel-1 and Sentinel-2 data
No full textInternational audienceIn this study, we present an operational methodology for mapping irrigated areas at plot scale, which overcomes the limitation of terrain data availability, using Sentinel-1 (S1) C-band SAR (synthetic-aperture radar) and Sentinel-2 (S2) optical time series. The method was performed over a study site located near Orléans city of north-central France for four years (2017 until 2020). First, training data of irrigated and non-irrigated plots were selected using predefined selection criteria to obtain sufficient samples of irrigated and non-irrigated plots each year. The training data selection criteria is based on two irrigation metrics; the first one is a SAR-based metric derived from the S1 time series and the second is an optical-based metric derived from the NDVI (normalized difference vegetation index) time series of the S2 data. Using the newly developed irrigation event detection model (IEDM) applied for all S1 time series in VV (Vertical-Vertical) and VH (Vertical-Horizontal) polarizations, an irrigation weight metric was calculated for each plot. Using the NDVI time series, the maximum NDVI value achieved in the crop cycle was considered as a second selection metric. By fixing threshold values for both metrics, a dataset of irrigated and non-irrigated samples was constructed each year. Later, a random forest classifier (RF) was built for each year in order to map the summer agricultural plots into irrigated/non-irrigated. The irrigation classification model uses the S1 and NDVI time series calculated over the selected training plots. Finally, the proposed irrigation classifier was validated using real in situ data collected each year. The results show that, using the proposed classification procedure, the overall accuracy for the irrigation classification reaches 84.3%, 93.0%, 81.8%, and 72.8% for the years 2020, 2019, 2018, and 2017, respectively. The comparison between our proposed classification approach and the RF classifier built directly from in situ data showed that our approach reaches an accuracy nearly similar to that obtained using in situ RF classifiers with a difference in overall accuracy not exceeding 6.2%. The analysis of the obtained classification accuracies of the proposed method with precipitation data revealed that years with higher rainfall amounts during the summer crop-growing season (irrigation period) had lower overall accuracy (72.8% for 2017) whereas years encountering a drier summer had very good accuracy (93.0% for 2019)
Assessing the resilience of farming systems on the Saïs plain, Morocco
No full textInternational audienceHighlights:• A participatory approach was used to study farm resilience after a shock.• Shocks differed according to farm type, but were all related to water.• Mental models were used with local actors to design future farming systems.• Performance was assessed according to eight complementary indicators.• According to local actors, all farm types would adapt, suggesting a good resilience.Abstract:The Mediterranean region is expected to be a hotspot for climate change, making the resilience of farming systems a major challenge. Some studies have used quantitative models at the farm scale to analyze the resilience of farming systems but with little involvement of stakeholders. We used a participatory approach with local actors on the Saïs plain of Morocco to design possible future states and qualitatively assess the resilience of typical farm types (FTs) experiencing major change. Our approach combined individual interviews of farmers and local actors, mainly public, with participatory collective meetings to identify representative FTs and their performance, project their evolutions and future performance in the face of change, and evaluate their resilience. Performance, defined according to literature, interviews and meetings, included different types of capital, income, yields, markets, support of public policies, and water access. Four FTs were considered: highly irrigated horticulture (FT1), rainfed cereals (FT2), partly irrigated cereal-legumes (FT3), and mostly irrigated fruit-tree/horticulture (FT4). The primary driver for FT2 and FT3 was climate change; for FT1 and FT4, it was limiting access to water resources. Participants designed more diversified systems for all FTs in relation to those changes. Rankings of FT performance did not change between current and future states. Performance did not evolve significantly, but FT4 was seen as the most resilient and FT2 the least. These qualitative results differ somewhat from other studies mobilizing quantitative approaches, but they highlight the potential of local adaptation to limit the impacts of global change on vulnerable agriculture
Detecting irrigation events using Sentinel-1 data
No full textInternational audienceBetter management of water consumption in irrigated agriculture is essential in order to save water resources. The objective of this study is to propose a new model capable of detecting the irrigation events using the Sentinel-1 (S1) Cband SAR (synthetic-aperture radar) in a near real-time approach. The proposed irrigation detection model relies on the change detection in the S1 backscattering coefficients at plot scale. A tree-based approach has been constructed to detect irrigation events by studying the behavior of the S1 backscattering coefficients following irrigation events at plot scale over three study sites located in Montpellier (southeast France), Tarbes (southwest France) and Catalonia (northeast Spain). Auxiliary data such as the NDVI (Normalized Difference Vegetation Index) and the soil moisture estimations were integrated as additional filters to reduce ambiguities related to vegetation growth and surface roughness. The results shows that the proposed model was capable of detecting 84% of the irrigation events over Montpellier. Over Catalonia site, 90.2% of the non-irrigated plots had no detected irrigation events whereas 72.4% of the irrigated plots had one and more detected irrigation events. In Tarbes, the analysis shows that irrigation events could still be detected even in the presence of abundant rainfall events during the summer season
Evaluation des déterminants de la compétitivité du secteur agricole libanais : étude de la filière pommes
No full textThe main objective of this study is to analyze and assess the competitiveness of the Lebanese agriculturalsector, taking into consideration the apple sector as a case study. In order to meet the objectives of thestudy, the method used was based on the « Filière » analysis approach combined with the transactioncosts approach, Porter's 5 forces in a global vision of strategic management. The search for a new modeladapting to the environmental mutation is becoming essential, given the current situation of the sector andspecifically the apple sector and changes at national and international level. Consequently, an adapted andcoherent strategy is essential to develop the competitiveness and the position of Lebanese products onforeign markets, especially the Egyptian one. In this context, and according to the growing apple markets,evolving under restricted sanitary standards, the change from mass production to differentiatingproduction is fundamental. This presupposes a shift from competition based on cost dominance tocompetition based on quality, service and costs. This development must be accompanied by a movementof concentration of producers as well large scale distributions. On the export side, Lebanese exportingcompanies are facing the deterioration of their competitive position in regional markets and specificallyEgypt; we believe that they are unable to export elsewhere. However, at the national level, the marketingof apples is guided by wholesalers. Producers fail to reference themselves at the supermarkets althoughthe physical attributes are considered trivial, and due to a lack of services associated with horticulturalproducts, reliability and speed. In parallel, demand for imported apples by supermarkets is increasingdespite the barriers imposed by the Lebanese government, while the Lebanese consumer becomes moredemanding as much for the quality as for the assortment. Furthermore, the modes of coordination betweenthe current players and the dysfunctions observed in the organization of the offer constitute majorobstacles to the implementation of adapted strategies. Accordingly, we believe that the problem lies inthese modes of coordination. The latter favors the domination of market mechanisms in a context ofuncertainty, and weakly minimizes transaction costs by encouraging short-term strategies, henceindicating low investment for quality production. This would result in an inappropriate offer anddifficulty in controlling marketing costs, in particular in terms of logistics and marketing costs. Thisadaptation process calls for deep restructuring for the Lebanese apple” filière”. However, in a competitivemarket where demand is evolving and segmented, the ability to create value and obtain the benefits whilereducing costs requires relevant strategic choices. As a result, we can observe the eruption of strategiesthat go in this direction, but their success depends on the involvement of all the players in the sector. Twocase studies will be analyzed to sketch a mode of governance that can be adapted to the strategies oflarge-scale retailers, which generate intensified competition at producer-supplier level. Indeed, the playersand the decision-makers must support the development of this new model to differentiate themselves fromcompeting countries. In order to achieve this objective, the implementation of technical development, achange in mentalities and values, is essential to ensure the sustainability of arboreal territories in a contextof increased global, regional and local economic competition.La présente étude a pour objectif principal d'analyser et d'évaluer la compétitivité du secteur agricole libanais, prenant comme étude de cas la filière pommes. En vue de répondre aux objectifs de l'étude, la méthode utilisée s'est basée sur l'approche d'analyse de filière conjuguée avec l'approche des coûts de transaction et le diamant de Porter dans la vision globale du management stratégique. La recherche d'un nouveau modèle devient primordiale vue la conjoncture actuelle du secteur agricole et spécifiquement de la filière pommes, devant faire face à des mutations au niveau national et international. Ainsi, une stratégie adaptée et cohérente s'impose pour développer la compétitivité et la position des produits libanais sur les marchés étrangers, surtout le marché égyptien. Dans ce cadre, au niveau international et sur les marchés croissants des pommes, évoluant selon des normes sanitaires restreintes, le changement d'une production de masse à une production de différenciation est une nécessité. Ceci suppose le passage d'une concurrence qui repose sur la domination par les coûts à une concurrence qui porte à la fois sur la qualité, le service et les coûts. Cette évolution doit s'accompagner d'un mouvement de concentration des producteurs et de la grande distribution. Du côté exportation,les entreprises exportatrices libanaises sont confrontées à la détérioration de leur position concurrentielle sur les marchés régionaux et spécifiquement sur le marché égyptien. De surcroît,nous pensons qu'ils n'arrivent pas à exporter ailleurs. Or, sur le marché libanais, la commercialisation des pommes est pilotée par les grossistes. Les fournisseurs n'arrivent pas à se référencer dans la grande distribution, en raison des attributs physiques peu différenciés, et à une absence des services associés aux produits horticoles, la fiabilité et la rapidité. En outre, la demande des pommes importées par la grande distribution augmente malgré l'entrave du gouvernement libanais, alors que le consommateur libanais devient plus exigeant autant pour la qualité que pour l'assortiment. Par ailleurs, les modes de coordination entre les acteurs et les dysfonctionnements dans l'organisation de l'offre constituent des freins importants pour la mise en œuvre de stratégies d'adaptation. Compte tenu des résultats, nous pensons que le problème réside dans ces modes de coordination. Ces derniers laissent place aux seuls mécanismes du marché dans un contexte d'incertitude, et minimisent faiblement les coûts de transaction en encouragent des stratégies de court terme marquant un faible investissement pour une production de qualité. Il en résulte une offre peu adaptée et une difficulté dans la maîtrise des coûts de mise en marché, en particulier au niveau des coûts logistiques et de commercialisation. Ce processus d'adaptation appelle des restructurations profondes pour la filière pommes libanaise. Or, sur un marché compétitif où la demande se segmente, la capacité de créer de la valeur et d'en retirer les avantages tout en diminuant les coûts imposent des choix stratégiques pertinents. De ce fait, on observe l'éruption de stratégies qui vont dans ce sens, mais leur succès repose sur l'implication de tous les acteurs de la filière. Dans ce cadre, deux études de cas seront analysées pour esquisser un mode de gouvernance adaptable aux stratégies de la grandes distribution, génératrices d'une concurrence exacerbée au niveau des producteurs-fournisseurs. Dans cette optique, les acteurs et les responsables des décisions doivent soutenir le développement de ce nouveau modèle pour se différencier des pays concurrents. Afin d'aboutir à cet objectif, la mise en place d'une évolution technique, d'un changement dans les mentalités et les valeurs, est indispensable pour pérenniser les territoires arboricoles dans un contexte de concurrence économique mondiale et régionale accru
Do small food businesses enable small farms to connect to regional food systems? Evidence from 9 European regions
No full textInternational audienceFor small farms across Europe, connecting to small food businesses offers a significant route to market. We analyse survey data from 85 small food businesses in nine European regions and explore the enabling and limiting conditions around this connectivity. We show how connectivity depends on context-based interrelationships among food system actors and consider the effects of these relations on small farm integration. Results show stronger connections when small food businesses are themselves farm-based. Weaker linkages are also apparent in the absence of public and social support. We argue that regional food systems can be enhanced by increasing small food businesses’ capacity to source from small farms, with the added benefit of increasing the viability of these small businesses
Consumer knowledge and perceptions of circular economy in the olive oil sector: a study of Tunisians consumers
No full textInternational audienc
How to adapt the education offer to job market needs–A case study of territory reform in Albania
No full textInternational audienceHigher Education Institutions (HEIs) in developing countries are faced with new and updated demands from the job market and must adapt their offering accordingly. This paper provides a methodological framework to adapt study and training programmes to address labour market needs. The case of territory administrative reform in Albania and the identification of the new skills required will be an illustrative example of that methodological framework.Albania has undertaken important reform that has completely modified its territory planning process from the traditional urban planning approach to a more holistic one referred to as territorial planning and development. However, a successful reform application must be focused on well-trained professionals. The main objective of this research is to address changing job market needs to be induced by new and forthcoming Albanian public policies on sustainable territory administration. Open interviews and structured questionnaires have been used to identify the required skills and competencies. Three skill clusters have been identified: 1) territory management skills, 2) environmental management skills, and 3) rural development policy skills with some specificities related to the scale of activity (central vs local). The results show that a corpus of skills appears to be transversal and useful for a large range of job descriptions at a local and central level
Economically and environmentally resilient farming systems in the Mediterranean Basin. A case study of the importance of pollination services in French arable crop farms
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Ecological-economic modeling of pollination complexity and pesticide use in agricultural crops
No full textInternational audienceRecent years have witnessed a substantial decline of both managed and wild bees in Europe due to the increase of pesticides use. Hence, many European agricultural systems depend on the buy/rental of managed bees in order to maintain sufficient levels of pollination services. However, this substitution of wild bees by managed ones apart from costly may be also ineffective as managed bees are not perfect substitutes for wild ones. In fact, a plethora of ecological studies showed that the presence of both bee species in the field and their complementarity effect generates an enhanced pollination activity which optimizes production. This study tries to evaluate this effect by developing an analytical ecological-economic model displaying farmer’s decisions between two agricultural inputs, pollination services and pesticides. Our results highlight that the economic value of this complementarity may offer to farmers an alternative optimum management strategy. This strategy lies on the production range where managed bees are working together with wild ones, offering an enhanced pollination to the crop production. Moreover, we showed that the adoption of a less toxic pesticide or better application methods by the farmers should increase the wild bees’ productivity and consequently, the total economic value of pollinators