L'économie circulaire (EC) émerge depuis les années 2000 dans le débat public, en opposition à l'économie linéaire, modèle dominant aux limites économiques et écologiques reconnues. Cette thèse constitue une première confrontation opérationnelle de l'EC à un système socio-écologique dépendant de la pêche, le Pays de la Cornouaille en Bretagne. Le système est délimité dans sa façade maritime avec la pêche côtière, seule considérée comme production locale.L'approche est systémique, multidimensionnelle et dynamique. L'analyse comporte trois volets : le premier sur l'amont du circuit en mer, le deuxième sur l'aval du système à terre et le dernier sur le système complet. Premièrement, le coût caché des rejets est visualisé via une analyse comptable de flux de matière ("Material Flow Cost Accounting" MFCA) adaptée à la pêche, proposé comme outil pertinent pour améliorer la performance économique et environnementale des pêcheurs. Deuxièmement, l’analyse de flux révèle une forte dépendance des activités à terre vis-à-vis des importations et exportations de bioressources halieutiques malgré un apport significatif de la pêche côtière à l'économie locale. Troisièmement, des scenarii sur le sous-système Sardine, du "business as usual" a l'EC, servent à proposer une trajectoire alternative de développement basée sur un "panier" de biens et services territorialises et la construction d'une valeur territoire à partir de ressources halieutiques locales. Pour atteindre cette EC durable, il s'agira d'optimiser l'utilisation des ressources locales et diminuer les externalités négatives, en plus d'aller vers une gouvernance partagée, adaptée à l'échelle du système socio-écologique considéré. / The years 2000 have favored the emergence of "Circular Economy" (CE) in the public debate, as opposed to the "linear economy", the dominant model that led to acknowledged economie and ecological limits. Our work is a first attempt to address the CE to a fishery-dependent socio-ecological System, the Cornouaille region in Brittany. The approach is systemic, multidimensional and dynamic. It implies the identification of marine boundaries, in which only Coastal fisheries are considered as a local production. The analysis is conducted along three main axes: an analysis of the upstream part at sea (fishing), an analysis looking at the downstream value chain, on land, and a third looking at the whole System. First, a Material Flow Cost Accounting (MFCA) analysis adapted to fisheries is proposed as a relevant tool to improve economy and environmental performance of fishers, providing evidence of hidden costs of fish discards.Second, the fish bioresource flow analysis indicates a strong dependency on importation and exportation flows to maintain land-based activities depending on sea products, albeit evidence of a significant contribution of Coastal fisheries to the local economy. Third, the exploration of the sardine sub-system through scenarii, ranging between from "business as usual" to those lined with CE, shows an alternative development trajectory, based upon a potential "basket of goods and services", a "territorial value", specifically linked to local fisheries. To achieve such a sustainable CE, we would need to not only aim at a more efficient use of local marine resources and decrease negative externalities, but also advocate for a shared governance, suited to the scale of the considered localised socio-ecological System.

Developments since the 20th century indicate that the wellbeing of communities makes for healthy national welfare in strong countries. Community wellbeing is thus a priority for policy makers and service providers. Conceptualization of a meaningful, holistic multidimensional measurement of community wellbeing at micro (community) level has been lacking. Such a concept and its measurement are essential when addressing social exclusion and development issues in the enhancement of community wellbeing is to produce worthwhile results. There is growing recognition that earlier understanding of community wellbeing failed to address development needs and processes at community level. Outsider stakeholder driven top-down one-dimensional community wellbeing (‘silo’) measurements did not address human development needs at community level. Meaningful measurement requires integrated frameworks addressing multidimensional issues conceptualizing wellbeing measurement at community level. Such measurement needs to be combined with the integrated inclusion of social capital influence through ‘insider-outsider’ partnerships. The research study purpose was to develop a community driven holistic, integrative wellbeing assessment model. This model could assist ‘insiders’ (community members) and ‘outsiders’ (policy makers, service providers and community development practitioners) in developing and implementing community driven initiatives towards improved wellbeing. The two main research questions were: 1) which macro level wellbeing assessment factors to consider in an aligned micro level wellbeing assessment? and 2) what is the associative relationship between wellbeing and social capital? Two descriptive sample surveys were conducted utilizing a structured questionnaire. Primary data findings contributed to finalization of a community level wellbeing assessment model. This model would enable estimation of the potential (push and pull) factors that influence the targeted success of suggested community development processes. The assessment model is community driven and owned, with spider and quadrant diagram graph tools indicating first the status of community wellbeing and social capital, then the associative relationships of wellbeing and social capital in ‘insider-outsider’ initiatives for wellbeing enhancement. / Development Studies / D. Phil. (Development Studies)

Dans les territoires irrigués exposés aux crises de gestion quantitative de l’eau, la sévérité des étiages dépend des interactions entre systèmes de culture, situations pédoclimatiques, hydrologie, lâchers d’eau et restriction d’irrigation. Dans de nombreuses situations, l’absence de nouvelles solutions de stockage et les tensions entre gestionnaires et usagers de l’eau rendent nécessaire la planification des étiages. Mes travaux explorent le potentiel de « la gestion spatiale » de l’eau pour mettre en adéquation la dynamique des prélèvements pour l’irrigation avec celle de l’offre en eau disponible (naturelle et stockée). Je propose une méthodologie participative de conception-évaluation d’organisations territoriales des activités agricoles, déployée sur l’aval du bassin versant de l’Aveyron (800 km²), en trois étapes: (1) modéliser le système socio-agro-hydrologique, (2) concevoir des alternatives de distribution spatiale des systèmes de culture, (3) conduire une évaluation intégrée des alternatives face à la variabilité climatique observée. Ces travaux combinent des méthodes, connaissances et outils « hard and soft », et font usage de la plateforme de simulation multi-agent MAELIA. Le processus a permis de formaliser des visions d’acteurs et de poser les bases d’une concertation multi acteur. Cependant la simulation des impacts de ces alternatives a montré leurs limites pour régler le problème de déficit structurel en eau. Cette démarche pourrait être prolongée pour aboutir à des propositions opérationnelles. / In irrigated landscapes exposed to quantitative water management crisis, the intensity of low flows depends on interactions between cropping systems, pedoclimatic situation hydrology, water releases and withdrawal restrictions. In many situations there are no opportunities for more water storage, thus tensions occur between water managers and users, which makes the planning of water demand dynamics necessary. My work explores the potentials in the “spatial management of water” to align the water demand dynamics with natural and stored water availability. I present a 3 step, participatory method to design and assess agricultural landscapes: (1) model the Social-Agro Hydrological system, (2) design alternative spatial distribution of the cropping systems, (3) carry an integrated assessment of those alternatives based on observed climatic variability. This method combines “hard” and “soft” methods, knowledge and tools, and uses the MAELIA multi-agent simulation platform. I tested the method tested in the downstream area of the Aveyron River (800 km² Southwestern France). It allowed to formalize the actors’ visions on alternative distributions of the cropping systems. However they showed to be limited in solving the water deficit issue. The method could be continued to reach operational proposals.

Increasingly unpredictable, extreme and erratic rainfall with higher temperatures threatens to undermine the adaptive capacity of food systems and ecological resilience of smallholder landscapes. Despite growing concern, land managers still lack quantitative techniques to collect empirical data about the potential impact of climatic variability and change. This thesis aims to assess how ecosystem services and function and how this links with biodiversity and human wellbeing in smallholder agro-ecosystems in a changing climate. To this end, rather than relying on scenarios or probabilistic modelling, space was used as a proxy for time to compare states in disparate climatic conditions. Furthermore, an integrated methodological framework to assess ecosystem services at the field and landscape level was developed and operationalised, the results of which can be modelled with measures of wellbeing. Various multidisciplinary analytical tools were utilised, including ecological and socio-economic surveys, biological assessments, participatory open enquiry, and documenting ethnobotanical knowledge. The study was located within monsoon rice farms in the Terai Plains of Nepal, and dry season vegetable farms in Northern Ghana. Sites were selected that are climatically and culturally diverse to enable comparative analysis, with application to broad areas of adaptive planning. The linkages that bring about biophysical and human changes are complex and operate through social, political, economic and demographic drivers, making attribution extremely challenging. Nevertheless, it was demonstrated that within hotter and drier conditions in Ghana long-tongued pollinators and granivores, important for decomposition processes and pollination services, are more abundant in farms. Results further indicated that in cooler and drier conditions in Nepal, the taxonomic diversity of indigenous and close relative plant species growing in and around farms, important for the provisioning of ecosystem services, decreases. All other things equal, in both Nepal and Ghana findings indicate that overall human wellbeing may be adversely effected in hotter conditions, with a potentially significantly lower yields, fewer months of the year in which food is available, higher exposure to natural hazards and crop loss, unemployment, and psychological anxiety. Yet, surveys indicate smallholders continue to maintain a fair diversity of species in and around farms, which may allow them to secure basic necessities from provisioning ecosystem services. Moreover, farmers may employ adaptive strategies such as pooling labour and food sharing more frequently, and may have greater access to communication, technology, and infrastructure. Novel methodological and empirical contributions of this research offer predictive insights that could inform innovations in climate-smart agricultural practice and planning.