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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

L'économie circulaire appliquée à un système socio-écologique halio-alimentaire localisé : caractérisation, évaluation, opportunités et défis / Circular economy in a small-scale fishery-dependent socio-ecological system : characteristics, evaluation, opportunities and challenges

Le Gouvello, Raphaëla 01 March 2019 (has links)
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.
72

A micro level model for assessing community development towards improved wellbeing

Hart, Cornelia Susanna 04 1900 (has links)
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)
73

Stewardship in an urban world : Civic engagement and human–nature relations in the Anthropocene

Enqvist, Johan January 2017 (has links)
Never before have humans wielded a greater ability to alter and disrupt planetary processes. Our impact is becoming so noticeable that a new geological epoch has been proposed – the Anthropocene – in which Earth systems might no longer maintain the stable and predictable conditions of the past 12 millennia. This is particularly evident in the rapid expansion of urban areas, where a majority of humans now live and where environmental changes such as rising temperatures and habitat loss are happening faster than elsewhere.  In light of this, questions have been raised about what a more responsible relationship between humans and the rest of the planet might look like. Scholars in sustainability science employ the concept of ‘stewardship’ in searching for an answer; however, with multiple different applications and definitions, there is a need to better understand what stewardship is or what novelty it might add to sustainability research. This thesis investigates stewardship empirically through two case studies of civic engagement for protecting nature in cities – Bengaluru, India and New York City, USA. Further, the thesis also proposes a conceptual framework for how to understand stewardship as a relation between humans and the rest of nature, based on three dimensions: care, knowledge and agency. This investigation into stewardship in the urban context uses a social–ecological systems approach to guide the use of mixed theory and methods from social and natural sciences. The thesis is organized in five papers. Paper I reviews defining challenges in managing urban social–ecological systems and proposes that these can more effectively be addressed by collaborative networks where public, civic, other actors contribute unique skills and abilities. Paper II and Paper III study water resource governance in Bengaluru, a city that has become dependent on external sources while its own water bodies become degraded and depleted.Paper II analyzes how locally based ‘lake groups’ are able to affect change through co-management arrangements, reversing decades of centralization and neglect of lakes’ role in Bengaluru’s water supply.Paper III uses social–ecological network analysis to analyze how patterns in lake groups’ engagements and collaborations show better fit with ecological connectivity of lakes.Paper IV employs sense of place methods to explore how personal bonds to a site shapes motivation and goals in waterfront stewardship in New York City. Finally,Paper V reviews literature on stewardship and proposes a conceptual framework to understand and relate different uses and underlying epistemological approaches in the field. In summary, this thesis presents an empirically grounded contribution to how stewardship can be understood as a human–nature relation emergent from a deep sense ofcare and responsibility, knowledge and learning about how to understand social–ecological dynamics, and theagency and skills needed to influence these dynamics in a way that benefits a greater community of humans as others. Here, the care dimension is particularly important as an underappreciated aspect of social–ecological relations, and asset for addressing spatial and temporal misalignment between management institutions and ecosystem. This thesis shows that care for nature does not erode just because green spaces are degraded by human activities – which may be crucial for promoting stewardship in the Anthropocene. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript. Paper 5: Manuscript.</p>
74

Quelles distributions spatiales des systèmes de culture pour limiter l'occurence des crises de gestion quantitative de l'eau ? Une démarche de conception évaluation sur le territoire irrigué de l'Aveyron aval / What alternative cropping systems spatial distributions to limit the risk of quantitative water management crises ? A design and assessment method for an irrigated landscape in the lower reaches of the Aveyron River

Murgue, Clément 17 December 2014 (has links)
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.
75

Une approche interdisciplinaire de la pertinence et de la faisabilité d'une co-gestion de la pêche récréative sur l'île d'Oléron : l'étrille, Necora puber (Linnaeus, 1767), comme modèle biologique / An interdisciplinary approach to assess the relevancy and feasibility of recreational fishing co-management on Oléron island : a target species, the velvet swimming crab (Necora puber, Linnaeus, 1767)

Coz, Richard 17 September 2013 (has links)
Parmi les nombreuses activités exercées sur les systèmes socio-écologiques littoraux, la pêche récréative a connu un essor important devenant ainsi un enjeu de développement durable. En France, les défauts de gouvernance de l'État dans la gestion du DPM invitent à s'interroger sur la pertinence et la faisabilité d'une co-gestion de ces pratiques de loisir. Ce paradigme, se voulant une alternative à une gestion top-down, prône la participation accrue des populations locales dans la gestion de l'environnement pour améliorer ses résultats. L'île d'Oléron ne déroge pas à ces constats qui sont renforcés par les modifications sociétales spécifiques aux territoires insulaires. Dans le cadre de recherches dont l'objet d'étude est une problématique sociétale, il est approprié de faire appel à une approche interdisciplinaire pour améliorer la pertinence des réponses apportées. Concernant la pêche à pied récréative à l'étrille, les résultats obtenus en biologie et en écologie mettent en évidence des caractéristiques qui semblent indiquer un faible impact potentiel à court comme à long termes de ces perturbations ponctuelles sur les populations locales. D'un point de vue sociétal, la pertinence d'une co-gestion de la pêche récréative est clairement établie par les nombreux conflits d'usages impliquant les pêcheurs récréatifs, le manque de moyens pour gérer la pratique et acquérir des données scientifiques, le manque de concertation, etc. La dynamique de développement du territoire oléronais et les initiatives locales à l'instar des conflits d'usages soutiennent l'idée de l'existence d'une « fenêtre politique » pouvant permettre la mise en place d'une co-gestion de la pratique dans les prochaines années, sous réserve d'une communication suffisante et d'une réelle volonté des acteurs concernés par la gestion de la pratique. / Among several other activities practice on coastal socio-ecological system, recreational fishing ones have significantly increased over the past few years, becoming an issue for sustainable development. In France, the weakness of states governance concerning DPM management, questions the relevancy and feasibility of a co-management policy for these leisure activities. This paradigm, constituting a good substitute for top-down management, recommends an increased participation of local populations for managing environments and improving their outcomes. Oléron Island is thus affected by these observations, which are intensified by societal changes distinguishing island territories. In the current research context, aiming at solving societal problematic, it is relevant to consider an interdisciplinary approach to provide relevant answers. Concerning recreational shellfish gathering targeting the velvet swimming crab, results in biology and ecology highlight some characteristics which should indicate a weak short and long terms potential impact of the disturbances affecting local populations. As regards to societal aspects, the relevancy of co-management is clearly demonstrated by several land-use conflicts, a lack of means to manage the practice and scientific data, the lack of consultation, etc. The territorial dynamic and local initiatives, as well as land-use conflicts, underline the existence of a “political window” which should allow the implementation of a co-management process for recreational fishing in the following years, subject to further efficient communication and a real desire from stakeholders concerned by the management of this practice.
76

Mathematical models of social-ecological systems: Coupling human behavioural and environmental dynamics

Sun, Tithnara Anthony 31 March 2020 (has links)
There is an increasing concern for the impact of humans on the environment. Traditionally, ecological models consider human influence as a constant or linearly varying parameter, whereas socioeconomic models and frameworks tend to oversimplify the ecological system. But tackling complex environmental challenges faced by our societies requires interdisciplinary approaches due to the intricate feedbacks between the socioeconomic and ecological systems involved. Thus, models of social-ecological systems couple an ecological system with a socioeconomic system to investigate their interaction in the integrated dynamical system. We define this coupling formally and apply the social-ecological approach to three ecological cases. Indeed, we focus on eutrophication in shallow freshwater lakes, which is a well-known system showing bistability between a clear water state and a turbid polluted state. We also study a model accounting for an aquifer (water stock) and a model accounting for a biotic population exhibiting bistability through an Allee effect. The socioeconomic dynamics is driven by the incentive that agents feel to act in a desirable or undesirable way. This incentive can be represented by a difference in utility, or in payoff, between two strategies that each agent can adopt: agents can cooperate and act in an environment-friendly way, or they can defect and act in an ecologically undesirable way. The agents' motivation includes such factors as the economic cost of their choice, the concern they feel for the environment and conformism to the collective attitude of the human group. Thus, the incentive to cooperate responds to the state of the ecological system and to the agents' collective opinion, and this response can be linear, nonlinear and monotonic, or non-monotonic. When investigating the mathematical form of this response, we find that monotonic non-linear responses may result in additional equilibria, cycles and basins of attraction compared to the linear case. Non-monotonic responses, such as resignation effects, may produce much more complicated nullclines such as a closed nullcline and weaken our ability to anticipate the dynamics of a social-ecological system. Regarding the modelling of the socioeconomic subsystem, the replicator dynamics and the logit best-response dynamics are widely used mathematical formulations from evolutionary game theory. There seems to be little awareness about the impact of choosing one or the other. The replicator dynamics assumes that the socioeconomic subsystem is stationary when all agents adopt the same behaviour, whereas the best-response dynamics assumes that this situation is not stationary. The replicator dynamics has formal game theoretical foundations, whereas best-response dynamics comes from psychology. Recent experiments found that the best-response dynamics explains empirical data better. We find that the two dynamics can produce a different number of equilibria as well as differences in their stability. The replicator dynamics is a limit case of the logit best-response dynamics when agents have an infinite rationality. We show that even generic social-ecological models can show multistability. In many cases, multistability allows for counterintuitive equilibria to emerge, where ecological desirability and socioeconomic desirability are not correlated. This makes generic management recommendations difficult to find and several policies with and without socioeconomic impact should be considered. Even in cases where there is a unique equilibrium, it can lose stability and give rise to sustained oscillations. We can interpret these oscillations in a way similar to the cycles found in classical predator-prey systems. In the lake pollution social-ecological model for instance, the agents' defection increases the lake pollution, which makes agents feel concerned and convince the majority to cooperate. Then, the ecological concern decreases because the lake is not polluted and the incentive to cooperate plummets, so that it becomes more advantageous for the agents to defect again. We show that the oscillations obtained when using the replicator dynamics tend to produce a make-or-break dynamics, where a random perturbation could shift the system to either full cooperation or full defection depending on its timing along the cycle. Management measures may shift the location of the social-ecological system at equilibrium, but also make attractors appear or disappear in the phase plane or change the resilience of stable steady states. The resilience of equilibria relates to basins of attraction and is especially important in the face of potential regime shifts. Sources of uncertainty that should be taken into account for the management of social-ecological systems include multistability and the possibility of counterintuitive equilibria, the wide range of possible policy measures with or without socioeconomic interventions, and the behaviour of human collectives involved, which may be described by different dynamics. Yet, uncertainty coming from the collective behaviour of agents is mitigated if they do not give up or rely on the other agents' efforts, which allows modelling to better inform decision makers.
77

Ecosystem services, biodiversity and human wellbeing along climatic gradients in smallholder agro-ecosystems in the Terai Plains of Nepal and northern Ghana

Thorn, Jessica Paula Rose January 2016 (has links)
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.
78

Second Chance Recovery Centre : the experiences of caregivers of Nyaope addicts

Mokutu, Kgothatso Selloane Lydia 12 1900 (has links)
Background: Drug rehabilitation is crucial for drug addicts. As much as drug rehabilitation (rehab) centres are helping in dealing with drug addiction. Some drug addicts may find that some of the drug rehabs do not meet their needs. Therefore, the study explored the experience of caregivers caring for nyaope addicts. Method: This study adopted a qualitative research approach and a case study design. The purposive sampling method was employed to select the sample. The sample comprised six caregivers. The structured interview and open-ended questionnaire were employed to collect data. An interview questionnaire was designed allowing the participants to respond at home and provide feedback. Their responses provided through this process were insufficient, participants were then requested face-to-face interviews and they agreed. Results: One of the main findings in this study was that caregiving affects the caregivers negatively. Caregiving has led to psychological and physical effects amongst the caregivers. Conclusion: A need was identified for support and awareness for the caregivers and rehabilitation centres in South Africa. This might reduce the relapse of substance abuse and help eradicate the number of substance abusers in South Africa. / Psychology / M.A. (Psychology (Research Consultation))

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