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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.
21

Opportunités du REDD+ pour l'aménagement durable des forêts tropicales et obstacles à son implantation en République démocratique du Congo : perspective juridique

Fimpa Tuwizana, Twison 08 1900 (has links)
La situation de la forêt tropicale dans les pays en développement en général, et en République Démocratique du Congo (RDC) en particulier, est inquiétante. Les émissions de dioxyde de carbone dues au déboisement sont de l’ordre de 1,6 GtCO2e/an, soit 17% des émissions mondiales de « gaz à effet de serre ». Sous l’égide de la Convention-cadre des Nations Unies sur les changements climatiques, le REDD+ a été institué pour lutter contre cette déforestation et la dégradation des forêts. Cette étude examine les différentes opportunités qu’offre ce programme pour l’aménagement écosystémique du couvert forestier de la RDC et les obstacles contextuels à sa mise en oeuvre. Pour la RDC, le REDD+ présente un certain nombre d’opportunités : réduction des émissions liées au déboisement et à la dégradation des forêts; amorce des travaux d’afforestation et de reforestation par une gestion durable des ressources conduisant à la création des emplois et favorisant la croissance des PIB et des exports; accroissement du rendement et maintien d’une plus grande couverture des besoins alimentaires. Le REDD+ peut favoriser la croissance du Produit intérieur brut agricole. Il peut contribuer à l’électrification des ménages et réduire de moitié les dépenses des ménages dépendant de l’exploitation minière et des hydrocarbures et, ainsi, générer des milliers d’emplois en infrastructures. Pour les populations locales et autochtones, il peut contribuer aussi à protéger et à valoriser les cultures liées à la forêt. Mais, face aux pesanteurs d’ordre juridique, politique, social, économique, technologique et culturel caractéristiques de ce pays, ces opportunités risquent d’être amenuisées, sinon annihilées. Étant donné que l’essentiel du déploiement du dispositif du REDD+ se réalisera dans les zones rurales congolaises, l’obstacle majeur reste le droit coutumier. La solution serait d’harmoniser les exigences et finalités du REDD+ non seulement avec le Code forestier de 2002 et ses mesures d’exécution mais aussi avec le droit coutumier auquel les communautés locales et autochtones s’identifient. / The situation of the rainforest in developing countries in general and the Democratic Republic of Congo (DRC) in particular is worrying. Emissions of carbon dioxide from deforestation are about 1.6 GtCO2e/an, or 17% of global emissions of "greenhouse gases". Under the auspices of the UN Framework Convention on Climate Change, REDD+ has been established to fight against the deforestation and degradation of forests. This study examines the different opportunities offered by the program for ecosystem-based management of forest cover in the DRC and contextual barriers to its implementation. For the DRC, REDD+ has a number of opportunities: reducing emissions from deforestation and forest degradation; work begins afforestation and reforestation for sustainable management of resources leading to job creation and promoting the growth of GDP and exports, increased yield and maintaining greater food needs. The REDD+ can promote the growth of the agricultural gross domestic product. It can contribute to the electrification of households and halve spending dependent on mining and oil and thus generate thousands of jobs in infrastructure. For local and indigenous communities, it can also help to protect and promote the cultures associated with the forest. But, faced with the burdens of legal, political, social, economic, technological and cultural characteristics of the country, these opportunities may be diminished, if not annihilated. Given that most of the deployment of the REDD+ will happen in Congolese rural areas, the major obstacle is the customary law. The solution would be to harmonize the requirements and objectives of REDD+ not only with the Forest Code of 2002 and its implementing rules but also with the customary law which local and indigenous communities identify.
22

Valuing Biological diversity in Navarino island, Cape Horn Archipelago, Chile - a choice experiment approach / Valoración de la diversidad biológica en isla Navarino, Archipiélago Cabo de Hornos, Chile - una aproximación con experimento de elección

Cerda, Claudia 03 July 2006 (has links)
No description available.
23

Évaluation, scénarios et viabilité écologique et économique des pêcheries côtières tropicales : application au cas de la Guyane française / Evaluation and ecological-economic scenarios of tropical coastal fisheries : the case of the french guiana

Cissé, Abdoul Ahad 02 July 2013 (has links)
La nécessité d'une approche intégrée des pêches est actuellement largement affirmée, notamment par la FAO, en particulier dans le contexte des pêcheries artisanales tropicales. Ces pêcheries à petites échelles, souvent multi-spécifiques sont très importantes en termes d'emploi et de production, y compris pour la sécurité alimentaire. Néanmoins ces pêcheries et la biodiversité exploitées sont souvent marquées, d'une part, par le manque de données rendant difficile leur gestion dans le cadre d'une approche écosystémique, d'autre part, par la complexité des systèmes écologiques et économiques sous-jacents incluant interactions trophiques et techniques.Cette thèse contribue à la mise au point d'outils bioéconomiques adaptés aux petites pêcheries tropicales dans la perspective d'une gestion durable des pêches fondée sur l'approche écosystémique. Dans cette perspective, la pêcherie côtière en Guyane Française constitue un cas d'étude particulièrement fécond. La thèse propose ainsi des évaluations multi-critères, des modèles bioéconomiques complexes et des scénarios de gestion viable pour cette pêcherie.Dans un premier temps l'analyse statistique multi-variée suggère un statut global satisfaisant de la pêcherie en termes de durabilité. Cependant des différences de performance sont notées au sein de la pêcherie, notamment au niveau des zones frontalières. Aussi des améliorations dans le mode de gestion sont proposées. Ensuite, à travers la modélisation bioéconomique, les projections des différents scénarios de pêche montrent qu'à long terme le niveau d'exploitation actuel peut ne pas être en adéquation avec la future augmentation de la demande locale et qu'une perte de biodiversité peut avoir lieu. Un scénario dit de « co-viabilité » conciliant des objectifs à la fois écologique, économique et social, avec une probabilité de réalisation satisfaisante, est mis en exergue. Enfin, la comparaison des comportements optimaux en situation coopératif et non coopératif, montre dans quelle mesure la viabilité est favorisée quand les acteurs coopèrent. Au-delà du diagnostic apporté pour le cas d'étude, la méthode utilisée s'avère prometteuse dans le contexte des petites pêcheries tropicales, tandis que l'approche de « co-viabilité » permet de trouver les modalités d'exploitation dans le cadre de compromis entre durabilité écologique et socio-économique, ce que les principes de gestion halieutiques traditionnels ne permettent généralement pas. / The need for an integrated approach to fisheries is now widely affirmed, including the FAO, in particular in the context of tropical artisanal fisheries. These small-scale fisheries, often multispecies are very important in terms of production, employment and food security. However these fisheries and the exploited resources are often characterized by a lack of data making difficult their management within an ecosystem approach, and by the ecological and economic system complexities including trophic and technological interactions.This thesis aims to contribute to the development of bioeconomic tools for small tropical fisheries in a sustainable management perspective based on the ecosystem approach. In this perspective, the French Guiana coastal fishery constitutes an interesting case study. The thesis proposes multi-criteria evaluations, complex bioeconomic models and viable management scenarios for this fishery. At first, multivariate statistical analysis suggests a satisfactory overall status of the fishery in terms of sustainability. However, some performance differences are noted within the fishery, particularly at border areas. Also, management improvements are proposed. Then, through bioeconomic modeling, projections of different fishing scenarios show that, in the long term, the current exploitation level may not be consistent with the future increase of local demand and a loss of biodiversity may occur. A scenario called "co-viability" reconciling ecological, economic and social objectives, with a high probability of achievement is exhibited. Finally, the comparison of optimal behavior in cooperative and non-cooperative conditions, confirms that harvest levels are greater when actors do not cooperate. Furthermore, it is shown that the state of the ecosystem depends on the fishing strategies and the type of interaction between species. Beyond the diagnosis made for the case study, the method is promising in the context of small tropical fisheries, while the co-viability approach allows finding the exploitation conditions under which ecological and socio-economic sustainability are meet, what the conventional fisheries management generally do not allow.
24

Regional Environmental Governance and Avenues for the Ecosystem Approach to management in the Baltic Sea Area

Söderström, Sara January 2017 (has links)
This thesis explores the avenues for the ecosystem approach to management in the Baltic Sea Region. This region is one of the most contaminated water bodies in the world, although the first Regional Seas Convention was created here and theregion has a long history of cooperation and environmental protection. The current environmental governance arrangements are examined with specific focuson governance structures, cross-sectoral integration and ecological boundaries.The ecosystem approach to management as both a tool and vision of holistic management of natural resources is traced through the evolution of environmental governance, as well as its manifestation in contemporary environmental policies in the region. It is found that the major EU directives, as well as HELCOM polices, promote the ecosystem approach and that its presence has increased inrecent years; it is now the major guiding principle in European marine governance. However, the governance structures impede implementation indifferent ways. The environmental problem areas in the region all require different governance arrangements, thus obstructing a holistic approach. The environmental problems per se also affect each other, necessitating far-reaching sectoral integration and cross-border cooperation, which at present is the major obstacle regarding implementation. The contemporary trends combining solid regionalisation through HELCOM with increased Europeanisation and macro regionalisation by different EU initiatives offer some promise, but the cross sectoral impediments must be resolved if the ecosystem approach is to become apractical approach and not just a policy principle.
25

An Ecosystem Approach to the Sustainability of Urbanizing Watersheds

Raposa, Sarah L 01 January 2011 (has links) (PDF)
Political boundaries make watershed planning difficult despite the influence of many state and federal programs. Broad, top-down, watershed initiatives fail to reach many municipalities due to human resources, time and legalities. Thus, a watershed ecosystem based approach to city planning should be utilized in order to integrate a holistic and scientific foundation for land use decisions. However, there is a need for research for developing and applying a watershed approach to urbanizing watersheds. The goal of this study is to provide a series of science based transferable recommendations upon which municipalities can make land use planning decisions. These recommendations are informed by a watershed modeling and prioritization study conducted with the community of Northampton, Massachusetts. Analyses of water resource planning options were made concerning future development scenarios using an approach which links water quality and quantity, land use and government. A required component of the ecosystem approach, stakeholder participation, applied the Deliberative Attribute Prioritization Procedure (DAPP) for the first time in this context to assess the relative of different environmental concerns. The results of these stakeholder focus groups showed the importance of several key attributes including land use, water quality, water quantity, and impacts to neighborhing communities that were utilized in the watershed models. This thesis provides an integrated tool for water resource planning at the municipal level. However, without the effective transfer of these recommendations into existing policies like zoning, the results of the study have limited use. Therefore implementation of recommendations within municipal planning documents is an important component. This information will be utilized to evaluate priority water resource protection overlays by providing quantitative information and decision making within a community. A citywide watershed model and analysis used to guide policy-making and decision-making will assist in fulfilling the community of Northampton’s continuing commitment to work toward economic, environmental, and equitable sustainability, as well as provide a model for other communities.
26

The value of marine conservation

Rees, Sian Elizabeth January 2012 (has links)
The marine environment provides essential ecosystem services that are critical to the functioning of the earth’s life support system and the maintenance of human well-being. Marine Protected Areas (MPAs) are recognised as being the mechanism though which marine natural capital may be conserved. This thesis focuses on the value associated with marine conservation in a case study area, Lyme Bay, England where a ‘closed area’ was created in 2008. A review of literature spanning 20 years shows that despite sound ecological knowledge of a marine area, the reliance on traditional neo-classical economic valuations for marine spatial planning can obscure other issues pertinent to the ecosystem approach. A further valuation of the marine leisure and recreation industry shows that the industry is of economic significance and that the MPA enables the protection of the most valuable sites but has limited benefits for protecting the full resource base. In terms of ecological value, a ‘service orientated framework’ was developed to enable decision makers to understand the links between benthic species, ecological function and indirect ecosystem services. Results spatially identify which ecosystem services occur and demonstrate the value of the MPA in ensuring delivery of these ecosystem services. In relation to the social value of the MPA the research reveals that support for the MPA is strong amongst the majority of stakeholder groups. Values are expressed as the economic, environmental and social benefits of the MPA. However, there have been clear social costs of the MPA policy and these have been borne by mobile and static gear fishermen and charter boat operators. Each valuation methodology can inform decision making. Though, if ecosystem service valuation is to become a deliberative tool for marine conservation and planning, then there is a need for a larger societal discussion on what activities and trade-offs society considers acceptable.
27

Análise ecológica e econômica da pesca marinha por meio de indicadores multiespecíficos / Ecological-economics analysis of marine fishery with multispecies indicators

Pincinato, Ruth Beatriz Mezzalira 20 December 2010 (has links)
Alterações no ecossistema marinho e nos estoques pesqueiros devido à pressão da pesca podem ser detectadas por meio de indicadores multiespecíficos. Geralmente, esses indicadores são aplicados a séries temporais de capturas aliados a dados bio-ecológicos dos recursos. Entretanto, abordagens alternativas baseadas em dados de comercialização do pescado podem ser utilizadas. Neste estudo foram aplicados vários indicadores multiespecíficos aos dados disponíveis da região Sudeste/Sul do Brasil, integrando aspectos ecológicos e econômicos de forma inédita para essa região. Para isto, utilizaram-se dados da estatística pesqueira e dados de comercialização de pescado entre 1968-2007, além de dados bio-ecológicos dos recursos (nível trófico, comprimento máximo, longevidade e profundidade). Foram analisadas as tendências desses parâmetros em relação aos desembarques, às quantidades comercializadas e aos preços de mercado. Os indicadores Índice Trófico Marinho, Fishing-in-Balance e Índice de Preço Relativo Logaritmizado também foram explorados. Foi realizada uma análise inferencial das tendências de preço e quantidade das principais categorias de mercado e de suas correlações. A avaliação ecológico-econômica evidencia uma tendência de escassez das espécies-alvo da pesca e de algumas espécies de nível trófico, longevidade e comprimento máximo altos, além do fenômeno \"pricing down the food web\". Portanto, a base de dados do mercado provou ser valiosa para compreender a dinâmica da pesca numa perspectiva ecossistêmica. / Changes in marine ecosystems and fisheries resources due to the fishing pressure can be detected by multispecies indicators. These are, usually, applied to catch or landing time series, jointly the resources bio-ecological data. However, there is an alternative approach, based on market data that could be used. In this study, several multispecies indicators were applied to data from Southeastern/Southern Brazil, integrating ecological and economics aspects to this region in an unprecedented way. Fishery landings and market values for the period 1968-2007 were used, besides bio-ecological classification of seafood categories (trophic level, longevity, maximum length and depth). Trends of these parameters by landings and market quantities and prices were analysed. The Marine Trophic Index, Fishing-in-Balance and the Logarithm Relative Price Index were also applied. Moreover, an inferential analysis of individual categories statistical trends in market prices and quantities and their correlations were done. The joint ecological-economic analysis provided evidence of the scarcity of most higher trophic level, longevity and maximum length categories and fisheries target species, besides the \"pricing down the food web\" phenomenon. Therefore, the market database proved to be priceless to understand the fishery dynamic in an ecosystem perspective.
28

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.
29

Análise ecológica e econômica da pesca marinha por meio de indicadores multiespecíficos / Ecological-economics analysis of marine fishery with multispecies indicators

Ruth Beatriz Mezzalira Pincinato 20 December 2010 (has links)
Alterações no ecossistema marinho e nos estoques pesqueiros devido à pressão da pesca podem ser detectadas por meio de indicadores multiespecíficos. Geralmente, esses indicadores são aplicados a séries temporais de capturas aliados a dados bio-ecológicos dos recursos. Entretanto, abordagens alternativas baseadas em dados de comercialização do pescado podem ser utilizadas. Neste estudo foram aplicados vários indicadores multiespecíficos aos dados disponíveis da região Sudeste/Sul do Brasil, integrando aspectos ecológicos e econômicos de forma inédita para essa região. Para isto, utilizaram-se dados da estatística pesqueira e dados de comercialização de pescado entre 1968-2007, além de dados bio-ecológicos dos recursos (nível trófico, comprimento máximo, longevidade e profundidade). Foram analisadas as tendências desses parâmetros em relação aos desembarques, às quantidades comercializadas e aos preços de mercado. Os indicadores Índice Trófico Marinho, Fishing-in-Balance e Índice de Preço Relativo Logaritmizado também foram explorados. Foi realizada uma análise inferencial das tendências de preço e quantidade das principais categorias de mercado e de suas correlações. A avaliação ecológico-econômica evidencia uma tendência de escassez das espécies-alvo da pesca e de algumas espécies de nível trófico, longevidade e comprimento máximo altos, além do fenômeno \"pricing down the food web\". Portanto, a base de dados do mercado provou ser valiosa para compreender a dinâmica da pesca numa perspectiva ecossistêmica. / Changes in marine ecosystems and fisheries resources due to the fishing pressure can be detected by multispecies indicators. These are, usually, applied to catch or landing time series, jointly the resources bio-ecological data. However, there is an alternative approach, based on market data that could be used. In this study, several multispecies indicators were applied to data from Southeastern/Southern Brazil, integrating ecological and economics aspects to this region in an unprecedented way. Fishery landings and market values for the period 1968-2007 were used, besides bio-ecological classification of seafood categories (trophic level, longevity, maximum length and depth). Trends of these parameters by landings and market quantities and prices were analysed. The Marine Trophic Index, Fishing-in-Balance and the Logarithm Relative Price Index were also applied. Moreover, an inferential analysis of individual categories statistical trends in market prices and quantities and their correlations were done. The joint ecological-economic analysis provided evidence of the scarcity of most higher trophic level, longevity and maximum length categories and fisheries target species, besides the \"pricing down the food web\" phenomenon. Therefore, the market database proved to be priceless to understand the fishery dynamic in an ecosystem perspective.
30

Modélisations de la dynamique trophique d'un écosystème Méditerranéen exploité : le Golfe de Gabès (Tunisie) / Modeling the trophic dynamics of an exploited Mediterranean ecosystem : the Gulf of Gabes (Tunisia)

Halouani, Ghassen 05 December 2016 (has links)
L’objectif de cette thèse est d’améliorer la compréhension du fonctionnement et de la structure trophique du golfe de Gabès en Tunisie. Afin de concilier exigences écologiques et exploitation des ressources marines, différents modèles écosystémiques ont été développés pour étudier sa dynamique trophique et contribuer à la réflexion sur la mise en place de plans de gestion. Un modèle trophique d’équilibre de masse « Ecospace » a été construit afin d’évaluer les conséquences écosystémiques de différentes mesures de gestion. Les résultats des simulations ont permis d’explorer les interactions entre la pêche côtière et la pêche au chalut benthique et d’identifier des zones où les mesures de gestion sont effectives. Un modèle end-to-end a également été appliqué pour expliciter la dynamique des espèces considérées, depuis le forçage climatique jusqu'à la pêche. Cette approche de modélisation consiste à forcer le modèle individu-centré « OSMOSE » par un modèle biogéochimique « Eco3MMed ». Ce modèle a permis d’établir une représentation cohérente du réseau trophique et de simuler des scénarios de gestion théoriques de mise en réserve. Le modèle end-to-end a également été utilisé pour étudier la sensibilité d’un ensemble d’indicateurs écologiques à la pression de pêche. Les résultats ont révélé que les indicateurs de taille sont les plus adaptés pour faire le suivi de l’impact de la pêche dans le golfe de Gabès. Au final, une approche comparative entre plusieurs écosystèmes méditerranéens a été mise en place avec le modèle EcoTroph pour comparer leurs structures trophiques et explorer les effets de plusieurs niveaux d’exploitation par l’analyse de leurs spectres trophiques. / The objective of this thesis is to improve the understanding of trophic structure and functioning of the gulf of Gabes in Tunisia. In order to reconcile environmental concerns and exploitation of marine resources, different ecosystem models have been developed to study the ecosystem dynamics and contribute to the discussion on the implementation of management plans. A spatial and temporal dynamic model “Ecospace” was built to evaluate the ecosystem consequences of different management measures based on scenarios derived from the current regulation. The results of simulations allowed to investigate the interactions between coastal and benthic trawl fishing and to identify areas where management measures are effective. An end-to-end model has been applied to the gulf of Gabes ecosystem to represent the dynamics of 11 high trophic level species, from climate forcing to fishing.This modelling approach consists in forcing the individual-based model "OSMOSE" by a biogeochemical model "ECO3M-Med". This model allowed to establish a coherent representation of the food web and simulate theoretical management scenarios of spatial fishing closure. The end-to-end model has also been used to study the sensitivity of a set of ecological indicators to fishing pressure. The simulation of different levels of fishing mortality showed that size indicators were the most relevant to monitor the impact of fishing in the gulf of Gabes. Finally, a comparative approach between several Mediterranean ecosystems was applied using the EcoTroph model to compare their trophic structures and explore the effects of different levels of fishing pressure through the analysis of their trophic spectra.

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