En Australie du Nord, une nouvelle catégorie d'acteurs sociaux aborigènes a émergé dans les années 1990 : les « rangers ». Fondés sur la professionnalisation et la formalisation de responsabilités « traditionnelles » envers la terre et la mer, leurs emplois et programmes sont présentés comme des mécanismes de « gestion des ressources naturelles » et de conservation de la biodiversité contrôlés par les communautés autochtones, tout comme un support de « développement » local. Cette thèse propose un regard critique sur le système des rangers en partant de la question suivante : constitue-t-il une manifestation « d'impérialisme écologique » ? L'ethnographie (2009-2010) des interactions sociales mises en jeu par les activités du groupe de rangers de la communauté de Ngukurr (Terre d'Arnhem, Territoire du Nord) y est associée à une contextualisation et à une analyse articulant échelles locale, régionale et nationale et discours international. Le système des rangers reflète diverses logiques endogènes et exogènes qui dépassent ses objectifs affichés de résilience environnementale et socio-économique. Il repose sur des rapports de pouvoir et des négociations complexes entre les différents acteurs impliqués (dont l'État australien), entre « savoirs écologiques traditionnels » et science, et entre rapports sociaux locaux et bureaucratiques. Cette étude met au jour le processus de bureaucratisation et les multiples ingérences et ambivalences inhérents à ce système, qui (re)produit des distinctions et tensions sociales. Elle souligne également la fonction de médiateurs qu'endossent les rangers ainsi que l'ambiguïté de la position de chercheur dans un tel contexte. / In Northern Australia, a new category of Indigenous social actors emerged in the 1990s: “rangers”. Their jobs and programmes are based on the professionalization and formalization of “traditional” responsibilities for the land and sea. They are presented as natural resource management and biodiversity conservation mechanisms controlled by Indigenous communities and as a basis for local “development”.This thesis proposes a critical view of the ranger system, starting from the following question: is this system a form of “ecological imperialism”? The ethnography (2009-2010) of the social interactions at work in the activities of the Ngukurr community's ranger group (Arnhem Land, Northern Territory) is combined with a contextualization and an analysis linking local, regional and national levels with the international discourse.The ranger system reflects various endogenous and exogenous logics that go beyond its stated aims of environmental and socioeconomic resilience. It is based on complex power relations and negotiations between the different actors involved (including the Australian State), between “traditional ecological knowledge” and science, and between local and bureaucratic social relationships. This study reveals the bureaucratization process and the many external interventions and ambivalences inherent in this system which (re)produces social distinctions and tensions. It also highlights the mediator or broker role played by the rangers as well as the ambiguous position of the researcher in such a context.

<div>The security, resilience and sustainability of water supply in urban areas are of major concern in cities around the world. Their dynamics and long-term trajectories result from external change processes, as well as adaptive and maladaptive management practices aiming to secure urban livelihoods. This dissertation examines the dynamics of urban water systems from a social-ecological-technical systems perspective, in which infrastructure and institutions mediate the human-water-ecosystem relationship. </div><div><br></div><div>The three concepts of security, resilience and sustainability are often used interchangeably, making the achievement of goals addressing such challenges somewhat elusive. This becomes evident in the international policy arena, with the UN Sustainable Development Goals being the most prominent example, in which aspirations for achieving the different goals for different sectors lead to conflicting objectives. Similarly, the scientific literature remains inconclusive on characterizations and quantifiable metrics. These and other urban water challenges facing the global urban community are discussed, and research questions and objectives are introduced in Section 1. </div><div><br></div><div>In Section 2, I suggest distinct definitions of urban water security, resilience and sustainability: Security refers to the state of system functioning regarding water services; resilience refers to ability to absorb shocks, to adapt and transform, and therefore describes the dynamic, short- to medium-term system behavior in response to shocks and disturbances; sustainability aims to balance the needs in terms of ecology and society (humans and the economic systems they build) of today without compromising the ability to meet the needs of future generations. Therefore, sustainability refers to current and long-term impacts on nature and society of maintaining system functions, and therefore affects system trajectories. I suggest that sustainability should include not only local effects, but consider impacts across scales and sectors. I propose methods for the quantification of urban water security, resilience and sustainability, an approach for modeling dynamic water system behavior, as well as an integrated framework combining the three dimensions for a holistic assessment of urban water supply systems. The framework integrates natural, human and engineered system components (“Capital Portfolio Approach”) and is applied to a range of case study cities selected from a broad range of hydro-climatic and socio-economic regions on four continents. Data on urban water infrastructure and services were collected from utilities in two cities (Amman, Jordan; Ulaanbaatar, Mongolia), key stakeholder interviews and a household survey conducted in Amman. Publicly available, empirical utility data and globally accessible datasets were used to support these and additional case studies. </div><div><br></div><div>The data show that community adaptation significantly contributes to urban water security and resilience, but the ability to adapt is highly heterogeneous across and within cities, leading to large inequality of water security. In cities with high levels of water security and resilience, adaptive capacity remains latent (inactive), while water-insecure cities rely on community adaptation for the self-provision of services. The framework is applied for assessing individual urban water systems, as well as for cross-city comparison for different types of cities. Results show that cities fall along a continuous gradient, ranging from water insecure and non-resilient cities with inadequate service provision prone to failure in response to extant shock regimes, to water secure and resilient systems with high levels of services and immediate recovery after shocks. Although limited by diverse constraints, the analyses show that urban water security and resilience tend to co-evolve, whereas sustainability, which considers local and global sustainable management, shows highly variable results across cities. I propose that the management of urban water systems should maintain a balance of security, resilience and sustainability.</div><div><br></div><div>The focus in Section 3 is on intra-city patterns and mechanisms, which contribute to urban water security, resilience and sustainability. In spite of engineering design and planning, and against common expectations, intra-city patterns emerge from self-organizing processes similar to those found in nature. These are related to growth processes following the principle of preferential attachment and functional efficiency considerations, which lead to Pareto power-law probability distributions characteristic of scale-free-like structures. Results presented here show that such structures are also present in urban water distribution and sanitary sewer networks, and how deviation from such specific patterns can result in vulnerability towards cascading failures. In addition, unbounded growth, unmanaged demand and unregulated water markets can lead to large inequality, which increases failure vulnerability. </div><div><br></div><div>The introduction of infrastructure and institutions for providing urban water services intercedes and mediates the human-water relationship. Complexity of infrastructural and institutional setups, growth patterns, management strategies and practices result in different levels of disconnects between citizens and the ecosystems providing freshwater resources. “Invisibility” of services to citizens results from maximized water system performance. It can lead to a lack of awareness about the effort and underlying infrastructure and institutions that operate for delivering services. Data for the seven cities illustrate different portfolios of complexity, invisibility and disconnection. Empirical data gathered in a household survey and key stakeholder interviews in Amman reveals that a misalignment of stakeholder perceptions resulting from the lack of information flow between citizens and urban managers can be misguiding and can constrain the decision-making space. Unsustainable practices are fostered by invisibility and disconnection and exacerbate the threats to urban water security and resilience. Such challenges are investigated in the context of urban water system traps: the poverty and the rigidity trap. Results indicate that urban water poverty is associated with local unsustainability, while rigidity traps combined with urban demand growth gravitate towards global unsustainability. </div><div><br></div><div>Returning to the city-level in Section 4, I investigate urban water system evolution. The question how the trajectories of urban water security, resilience and sustainability can be managed is examined using insights from hydrological and social-ecological systems research. I propose an “Urban Budyko Landscape”, which compares urban water supply systems to hydrological catchments and highlights the different roles of supply- and demand-management of water and water-related urban services. A global assessment of 38 cities around the world puts the seven case studies in perspective, emphasizing the relevance of the proposed framework and the representative, archetypal character of the selected case studies. </div><div><br></div><div>Furthermore, I examine how managing for the different dimensions of the CPA (capital availability, robustness, risk and sustainable management) determines the trajectories of urban water systems. This is done by integrating the CPA with the components of social-ecological system resilience, which explain how control of the different components determines the movement of systems through states of security and resilience in a stability landscape. Finally, potential feedbacks resulting from the global environment are investigated with respect to the role that globally sustainable local and regional water management can play in determining the trajectories of urban water systems. These assessments demonstrate how the impact of supply-oriented strategies reach beyond local, regional and into global boundaries for meeting a growing urban demand, and come at the cost of global sustainability and communities elsewhere.</div><div><br></div><div>Despite stark differences between individual cities and large heterogeneities within cities, convergent trends and patterns emerge across systems and are revealed through application of the proposed concepts and frameworks. The implications of these findings are discussed in Section 5, and are summarized here as follows: </div><div>1) The management of urban water systems needs to move beyond the security and resilience paradigms, which focus on current system functioning and short-term behavior. Sustaining a growing global, urban population will require addressing the long-term, cross-scale and inter-sector impacts of achieving and maintaining urban water security and resilience. </div><div>2) Emergent spatial patterns are driven by optimization for the objective functions. Avoiding traps, cascading failure, extreme inequality and maintaining global urban livability requires a balance of supply- and demand-management, consideration of system complexity, size and reach (i.e., footprint), as well as internal structures and management strategies (connectedness and modularity).</div><div>3) Urban water security and resilience are threatened by long-term decline, which necessitates the transformation to urban sustainability. The key to sustainability lies in experimentation, modularization and the incorporation of interdependencies across scales, systems and sectors.</div><div><br></div>

Made available in DSpace on 2016-08-10T10:55:15Z (GMT). No. of bitstreams: 1 Paulo Lopes da Silva.pdf: 2017866 bytes, checksum: 9d8986584beaa350fa0d44c75ba8bf36 (MD5) Previous issue date: 2006-08-16 / The increasing quality lost of underground water all over the world, due to intensified antropic action during many decades, may make impracticable the future use of this natural resource. The modernity including its promise of adventure, power, joy, growth, interior change and change of the things around it (...) is at the same time the threat to all we have, all we know, all we are (Berman, 1988). According to this idea, the environment issue claims the problematicals consequences of the modernity and capitalist dynamics. Many are the environment problems, such as the freatic water pollution. These resources already supply more than 50% of the world population with water. The way today we face the environment problem and the way we understand them, its instruments, its politics such as all the dynamic brought in the search of its confrontation, are part of the big questions of this century. The freatic water environment problems occurs whenever more people demand higher life style standard with cheaper technologies, even if the involuntary sub products include the soil degradation, the toxic polluter, the animal species´ extinction or the climate changes. The environment is the totality of physiographic factors (soil), water, forest, relief, geology, landscape, meteorological factors and climate factors added to psycho-socials inherent to human nature (such as behavior, well-being, mind spirit, job, health, food) added to sociological factors such as culture, civility, sociability, respect and peace. So the planet Earth should be considered as a unique system. As we expand our understanding about the system which controls the environment and its never-ending interconnections, potential solutions will consolidate. The study of freatic water systems capacity/potentiality and natural geosystems as support to human needs will be a way of consolidating the scientific knowledge. It will do the necessary inter-relation between the natural environment and human potentiality. This way, an increasing consciousness related to environment issue appears as the possibility of the union between human and nature, both can t be analyzed as excludents poles. In the next pages, Goiânia and Aparecida de Goiânia cities are explore about yours underground water. / A crescente perda da qualidade das águas subterrâneas em todo o mundo, devido à ação antrópica intensificada ao longo de muitas décadas, pode inviabilizar a utilização futura desse recurso natural. A modernidade dentro de sua promessa de aventura, poder, alegria, crescimento, autotransformação e transformação das coisas ao seu redor (...) é ao mesmo tempo ameaça a tudo que temos, tudo o que sabemos, tudo o que somos . Nesse sentido a questão ambiental evoca as conseqüências problemáticas da modernidade e da dinâmica capitalista. Vários são os problemas ambientais, entre eles a poluição dos lençóis freáticos, que já abastecem mais de 50% da população mundial, a maneira que hoje enfrentamos, a circunstância como se dá esse entendimento, de seus instrumentos, de suas políticas, assim como toda a dinâmica na busca de seu enfrentamento fazem parte das grandes questões do nosso século. Os problemas ambientais com os lençóis freáticos surgem porque cada vez mais pessoas exigem padrões de vida mais altos com tecnologias mais baratas, mesmo que os subprodutos involuntários incluam a degradação dos solos, os poluentes tóxicos, a extinção de espécies animais ou alterações climáticas. Assim o meio ambiente sadio, ou seja, a totalidade dos fatores fisiográficos tais como o solo, a água, a floresta, o relevo, a geologia, a paisagem, fatores meteoros-climáticos mais os fatores psicossociais inerentes á natureza humana (comportamento, bem-estar, estado de espírito, trabalho, saúde, alimentação, etc.) somados aos fatores sociológicos como cultura, civilidade, convivência, o respeito, a paz etc. é que iluminará a sobrevivência humana. Dessa forma, planeta Terra deve ser visto como um único sistema e na medida em que expandirmos nossa compreensão sobre o sistema que controla o meio ambiente, das suas infinitas interligações, soluções potenciais se consolidarão. O estudo da capacidade/potencialidade dos sistemas freáticos e geossistemas naturais, como suporte às necessidades humanas, é ou será uma forma de consolidar o conhecimento cientifico e que dará a inter-relação necessária entre o meio natural e as potencialidades humanas. Desse modo, uma crescente conscientização acerca da questão ambiental, surge como a possibilidade de união entre o HOMEM e a NATUREZA, que não podem ser tomados como pólos excludentes. Nas páginas seguintes, exploram-se as condições ambientais, especialmente o lençol freático subterrâneo das cidades de Goiânia e Aparecida de Goiânia.

Increased demands on water supplies caused by population expansion, saltwater intrusion, and drought have led to water shortages which may be addressed by use of recycled water as recycled water products. Study I investigated recycled water production in Florida and California during 2009 to detect gaps in distribution and identify areas for expansion. Gaps were detected along the panhandle and Miami, Florida, as well as the northern and southwestern regions in California. Study II examined gaps in distribution, identified temporal change, and located areas for expansion for Florida in 2009 and 2015. Production increased in the northern and southern regions of Florida but decreased in Southwest Florida. Recycled water is an essential component water management a broader adoption of recycled water will increase water conservation in water-stressed coastal communities by allocating recycled water for purposes that once used potable freshwater.

Light Detection and Ranging (Lidar) data are used to report the temporal and spatial patterns of subsidence as well as the potential contributors to subsidence within the Barataria and Terrebonne Bays. In recent decades, subsidence in southeast Louisiana has become a topic of substantial and growing concern to the scientific community, the local residents, and all those invested in the region. Lidar data were acquired from the United States Geological Survey (USGS) and the LSU Center for Geoinformatics. The data has been manipulated to map the differenced Lidar, complete an instantaneous slope analysis, and determine the thickness of the Holocene sediments. The goal was to gain a more comprehensive understanding of the subsidence patterns and the dynamic processes driving subsidence within the study area. These efforts provide a better ability to plan for the future of the Louisiana working coast and mitigate against relative sea level rise and coastal land loss.

Over the past half century, the USDA Forest Service has increasingly faced diverse and often competing demands for forest resources, ranging from recreation, to ecosystem services, and timber supply. Building positive community-agency relationships has become increasingly important. Such relationships can improve community support for forest planning and management activities, ultimately making the agency more efficient and effective, while also providing economic and social benefit to local communities. The development of social capital may play an important role in promoting positive agency-community relationships. Broadly defined, the term refers to the social networks between individuals and groups that create a willingness and ability to act collectively toward a common goal. This study focuses on the impact that a partnership between the Colville National Forest and Northeast Washington Forestry Coalition has had on rural Northeast Washington communities. Overall, our study suggests the partnership has positively impacted networks among community members and networks between the community and the Forest Service. However, there is room for improvement. Many study participants were not familiar with important details about the Coalition's membership and objectives, or how its work may impact them or their community. Targeted outreach efforts will likely lead to greater support for the partnership. Such efforts could also strengthen networks among community members and community-agency networks as individuals learn how the partnership can benefit them and issues they care about. / Graduation date: 2012

In parallel with land devolution, the Government of Vietnam has launched reforestation programs aiming to increase the forest cover of the country and to improve the living of local population. In this context, conflicts between the state and local people over land and forest have been entailed or even intensified. To be successful, restoration must „fit‟ with ongoing local patterns of land and forest use. In the uplands of Vietnam, it is recognised that understanding of the current land and forest use by ethnic minority groups is crucial for objective oriented development of land and forest management. However, such understanding is lacking to a wide extent. This research looks into the current land and forest use by the Hmong people and tries to elaborate scenario for harmonising the governmental reforestation program with local patterns of land and forest use. The conceptual framework of the research is adapted from the Human Ecosystem Model (Machlis et al., 1997). For this study, both case study and survey are conducted. Three Hmong villages considered as three cases are selected based on predetermined criteria. In each of the selected villages, a mix of qualitative and quantitative methods, including Rapid Rural Appraisal, Land Use Inventory, Forest Inventory and Household Survey, is employed to capture the required data sets. The study results show the current patterns of land and forest use by the Hmong people in their village territories for their subsistence. Land use is virtually shaped by the physical attributes of the land and closely related to elements of the critical resources and the social system at the village, such as population, production tools, cropping seasons, wealth and knowledge. There are also close links between tree/forest use and the elements of the critical resources and the social system at the village, such as extraction tools, belief in Gods, extracting seasons, gender and local knowledge. Furthermore, following cultural traditions, the uses of forests customarily claimed either by individual households or by individual clans or by the village as a whole are strictly regulated by the system of customary tenure, customary and locally developed rules, and traditional and village institutions rather than the system of formal tenure, rules and institutions. However, the informal system has not been officially recognised by the state yet. The governmental reforestation project has been followed top-down approach, not taking into account the local reality. The project has brought about no tangible benefits to the villagers in terms of cash, forest products and others. Instead, conflicts between the state institutions and the villagers over land and forest have arisen. Lack of the villagers‟ participation in planning and decision-making concerning the project is the main reason explaining the conflict situations. It is posited that participatory planning of the project at village level can help to harmonise the project with local pattern of land and forest use. The human ecosystem model serves to integrate data related to concerned variables, and has been used as the basis for the elaboration of the harmonising scenario. Besides the involvement of the state/state institutions and the villagers/village institutions, involvement of a mediator as a third party seems to be helpful to harmonise the contrary positions of the two principle parties with regard to the use and management of land and forest resources. / Im Zuge der Dezentralisierung für den Bereich der Landnutzung hat die Regierung Vietnams Programme zur Wiederaufforstung initiiert, die auf Erweiterung der Waldbedeckung und Verbesserung des Lebens lokaler dörflicher Bevölkerung abzielen. In diesem Zusammenhang traten jedoch Konflikte zwischen Staat und lokaler Bevölkerung zu Tage oder bestehende Konfliktsituationen haben sich verstärkt. Programme der Wiederbegründung von Wald können nur erfolgreich sein, wenn sie mit aktuellen lokalen Mustern der Land- und Waldnutzung abgestimmt sind. In den Berggebieten Vietnams ist das Verständnis der Land- und Waldnutzung durch ethnische Minderheiten von zentraler Bedeutung für die zielorientierte Entwicklung der Bewirtschaftung von Land und Wald. Bisher fehlt das entsprechende Verständnis weitgehend. Vorliegende Forschung erkundet die derzeitige Land- und Waldnutzung der ethnischen Gruppe der Hmong. Ein Szenario zur Harmonisierung des staatlichen Aufforstungsprogramms mit lokaler Land- und Waldnutzung wird erarbeitet. Das konzeptionelle Vorgehen folgt dem Human Ecosystem Model (HEM) nach Machlis et al. (1997). Die Forschung umfasst Fallstudie und Survey. Drei Hmong-Dörfer repräsentieren drei Fallstudien, die auf der Grundlage vorbestimmter Kriterien ausgewählt wurden. In jedem der Dörfer wurden die erforderlichen Datensätze durch ein Mix von qualitativen und quantitativen Methoden wie Rapid Rural Appraisal, Landnutzungsinventur, Waldinventur und Befragung der Haushalte erhoben. Die Ergebnisse der Studie zeigen die derzeitigen Muster von Land- und Waldnutzung der Hmong in den Territorien ihrer Dörfer mit Orientierung auf Sicherung des Lebens. Die Landnutzung ist wesentlich bestimmt durch die natürlichen Eigenschaften des Landes und eng gebunden an Elemente der „kritischen Ressourcen“ und des „sozialen Systems“ auf Dorfebene wie Demografie, Geräte der Produktion, Wachstumsperioden, Wohlstand und Wissen. Gleiches gilt für die Waldnutzung mit dem Beziehungsgefüge zwischen Nutzung und Elementen der „kritischen Ressourcen“ sowie des „sozialen Systems“ im Dorf wie Gerät für die Ernte, Glaube an Gottheiten, Erntezeiträume, Geschlechter und lokales Wissen. Im Weiteren erfolgt die Waldnutzung vor allem auf traditioneller Grundlage durch Haushalte, Clans oder Dorfgemeinschaften entsprechend strikter Regelung im Rahmen des Gewohnheitsrechts, des traditionellen Besitzes, traditioneller und lokal entwickelter Regeln, traditioneller und anderer dörflicher Institutionen im Vergleich zu formalem Besitz, formalen Regeln und Institutionen. Allerdings ist das informelle System staatlich bis jetzt nicht anerkannt. Das staatliche Wiederaufforstungsprojekt folgt dem typischen top-down Verfahren ohne Beachtung der lokalen Realität. Das Projekt erbrachte keine nennneswerten Vorteile für die Dorfbewohner in Form von Geld, Waldprodukten o. a. Im Gegenteil, es haben sich Konflikte zwischen den staatlichen Institutionen und den Dorfbewohnern um Land und Wald ergeben. Fehlende lokale Beteiligung an Projektplanung und Entscheidungsfindung erklären die Konfliktsituation. Es ist zu schlussfolgern, dass partizipative Planung auf Dorfebene helfen kann, das Projekt mit den lokalen Bedingungen von Land- und Waldnutzung zu harmonisieren. Das Human Ecosystem Model diente dazu, relevante Variable zu integrieren und wurde als Grundlage für die Erarbeitung des Szenarios zur Harmonisierung genutzt. Neben dem Staat und den Dörfern wird die Beteiligung eines Mediatoren als dritter Partei für die Harmoniserung der gegensätzlichen Positionen der zwei wichtigen Interessengruppen zu Nutzung und Management von Land- und Waldressourcen als nützlich erachtet.

Cette thèse est composée de trois articles en économie des ressources naturelles non-renouvelables. Nous considérons tour à tour les questions suivantes : le prix in-situ des ressources naturelles non-renouvelables ; le taux d’extraction optimal et le prix des res- sources non-renouvelables et durables. Dans le premier article, nous estimons le prix in-situ des ressources naturelles non-renouvelables en utilisant les données sur le coût moyen d’extraction pour obtenir une approximation du coût marginal. En utilisant la Méthode des Moments Généralisés, une dynamique du prix de marché derivée des conditions d’optimalité du modèle d’Hotelling est estimée avec des données de panel de 14 ressources naturelles non-renouvelables. Nous trouvons des résultats qui tendent à soutenir le modèle. Premièrement, le modèle d’Hotelling exhibe un bon pouvoir explicatif du prix de marché observé. Deuxièmement, bien que le prix estimé présente un changement structurel dans le temps, ceci semble n’avoir aucun impact significatif sur le pouvoir explicatif du modèle. Troisièmement, on ne peut pas rejeter l’hypothèse que le coût marginal d’extraction puisse être approximé par les données sur le coût moyen. Quatrièmement, le prix in-situ estimé en prenant en compte les changements structurels décroît ou exhibe une forme en U inversé dans le temps et semble être corrélé positivement avec le prix de marché. Cinquièmement, pour neuf des quatorze ressources, la différence entre le prix in-situ estimé avec changements structurels et celui estimé en négligeant les changements structurels est un processus de moyenne nulle. Dans le deuxième article, nous testons l’existence d’un équilibre dans lequel le taux d’extraction optimal des ressources non-renouvelables est linéaire par rapport au stock de ressource en terre. Tout d’abord, nous considérons un modèle d’Hotelling avec une fonction de demande variant dans le temps caractérisée par une élasticité prix constante et une fonction de coût d’extraction variant dans le temps caractérisée par des élasticités constantes par rapport au taux d’extraction et au stock de ressource. Ensuite, nous mon- trons qu’il existe un équilibre dans lequel le taux d’extraction optimal est proportionnel au stock de ressource si et seulement si le taux d’actualisation et les paramètres des fonctions de demande et de coût d’extraction satisfont une relation bien précise. Enfin, nous utilisons les données de panel de quatorze ressources non-renouvelables pour vérifier empiriquement cette relation. Dans le cas où les paramètres du modèle sont supposés invariants dans le temps, nous trouvons qu’on ne peut rejeter la relation que pour six des quatorze ressources. Cependant, ce résultat change lorsque nous prenons en compte le changement structurel dans le temps des prix des ressources. En fait, dans ce cas nous trouvons que la relation est rejetée pour toutes les quatorze ressources. Dans le troisième article, nous étudions l’évolution du prix d’une ressource naturelle non-renouvelable dans le cas où cette ressource est durable, c’est-à-dire qu’une fois extraite elle devient un actif productif détenu hors terre. On emprunte à la théorie de la détermination du prix des actifs pour ce faire. Le choix de portefeuille porte alors sur les actifs suivant : un stock de ressource non-renouvelable détenu en terre, qui ne procure aucun service productif ; un stock de ressource détenu hors terre, qui procure un flux de services productifs ; un stock d’un bien composite, qui peut être détenu soit sous forme de capital productif, soit sous forme d’une obligation dont le rendement est donné. Les productivités du secteur de production du bien composite et du secteur de l’extraction de la ressource évoluent de façon stochastique. On montre que la prédiction que l’on peut tirer quant au sentier de prix de la ressource diffère considérablement de celle qui découle de la règle d’Hotelling élémentaire et qu’aucune prédiction non ambiguë quant au comportement du sentier de prix ne peut être obtenue de façon analytique. / This thesis consists of three articles on the economics of nonrenewable natural re- sources. We consider in turn the following questions : the in-situ price of nonrenewable natural resources, the optimal extraction rate and the price of nonrenewable and durable resources. The purpose of the first article is to estimate the in-situ price of nonrenewable natural resources using average extraction cost data as proxy for marginal cost. Using the regime switching Generalized Method of Moments (GMM) estimation technique, a dynamic of the market price derived from the first-order conditions of a Hotelling model is estimated with panel data for fourteen nonrenewable resources. I find results that tend to support the model. First, it appears that the Hotelling model has a good explanatory power of the observed market prices. Second, although the fitted prices seem to be subject to structural breaks over time, this does not have a significant impact on the explanatory power of the model. Third, there is evidence that marginal extraction cost can be approximated by average extraction cost data. Fourth, when allowing for structural breaks, estimates of the in-situ price decrease or exhibit an inverted U-shape over time and appear to be positively correlated with the market price. Fifth, for nine of the fourteen minerals, the difference between the estimates of the in-situ price with and without allowing for structural breaks is a zero-mean process.

Community-based natural resource management (CBNRM) related to protected areas (PAs) originated in the 1980’s in Zimbabwe, Africa, in the buffer zone communities of Africa’s National Parks. CBNRM attempted to address the problems associated with colonial, protectionist style ‘fence and guns’ conservation management approaches, which excluded resource-based communities from conservation areas. CBNRM attempts to meet the biodiversity conservation objectives of conservation areas, and the sustainable development and livelihood objectives of neighbouring communities. While CBNRM initiatives have been well documented internationally over the past decades, little is known about the status of CBNRM within Canada. In order to bridge this knowledge gap and to link trends in conservation and protected areas management internationally to Canada and to British Columbia (BC), this thesis examines the potential for community-based natural resource management (CBNRM) affiliated with BC's Protected Area System. “Potential” is determined by comparing the situation in BC to the international CBNRM experience. The study draws on a sample of Conservancies from the categories of the BC Protected Area (PA) System, focusing particularly on the nine Sea-to-Sky Land and Resource Management Plan (LRMP) Area Conservancies and neighbouring First Nations communities: Squamish, L’il’wat and In-SHUCK-ch. Information has been obtained through interviews (guided by semi-structured questionnaires) conducted with BC government informants and First Nations representatives, supplemented by key documents. The questionnaire examined the potential for CBNRM according to a.) the community's perspective: potential (costs and) benefits of the protected area, including goods and services, cultural and social benefits and sustainable economic development opportunities provided by the protected area; and benefits of community involvement in natural resource management and protected area governance; and b.) the conservation perspective: benefits through community cooperation in biodiversity conservation within the targeted protected area. Other factors that have been identified through the international experience to affect CBNRM initiatives, such as use regulation; tenure; policies and legislation; awareness of and support for the protected area; and community capacity were thoroughly examined across all sources of information. This study finds that there is potential for CBNRM affiliated with the BC PA system in protected area designations such as ‘Conservancies’. Potential relates to the role of CBNRM in biodiversity conservation, meeting the aspirations of BC’s First Nations communities, and in recognizing First Nations as legitimate stakeholders in protected areas and conservation management. As in the international experience, numerous social, political, economic and other factors present opportunities and challenges to the adoption of CBNRM in BC. This thesis concludes with key recommendations for protected areas and conservation management in BC and Canada and identifies opportunities to further explore key topic areas that arose from the research findings.

This thesis enters the context of smallholder agriculture communities in the developing world. It explores the potentials of biochar and what biochar systems could bring to the smallholder communities while simultaneously bringing environmental benefits. It then acknowledges the challenges of diffusion –the spreading of an unfamiliar innovation. It seeks to answer the question of what will make diffusion of biochar systems more successful in the smallholder context, fixating on the characteristic of compatibility as well as the role local community members can play in making a new biochar system more visible to the rest of the communities.