京都大学 / 新制・課程博士 / 博士(地域研究) / 甲第24015号 / 地博第294号 / 新制||地||113(附属図書館) / 京都大学大学院アジア・アフリカ地域研究研究科東南アジア地域研究専攻 / (主査)教授 三重野 文晴, 教授 河野 泰之, 准教授 小坂 康之, 教授 水野 広祐 / 学位規則第4条第1項該当 / Doctor of Area Studies / Kyoto University / DGAM

La thèse pose l’hypothèse que la construction des barrages hydroélectriques pourrait être un moteur de développement harmonieux entre montagnes et plaines. L’objectif serait de relier politiques de développement des barrages hydroélectriques et politiques agricoles en fonction des stratégies individuelles et des contraintes physiques et socio-économiques. Depuis les années 2000, dans toute l’Asie du Sud-Est, de nombreux projets de grands barrages hydroélectriques sont construits ou en construction pour répondre à la forte croissance de la demande en énergie, entraînant de grandes menaces sur la gestion de l’eau et l’environnement d’une part, et imposant d’importants déplacements de population d’autre part. Dans ces régions de montagne, les processus d’érosion représentent un risque majeur à la fois pour le comblement des lacs de barrage et pour la productivité agricole. Aussi grands investisseurs, pour la durée de vie des barrages hydroélectriques, et petits exploitants, pour leurs moyens de subsistance, se retrouvent également impactés. Le défi est de reformuler la relation entre la planification et la gestion des barrages hydroélectriques, et la planification et la gestion des terres agricoles des zones amont des barrages. Même si l’accompagnement socio-économique a été très largement amélioré de la part de l’Etat vietnamien, les agriculteurs déplacés et non-déplacés sont encore largement à subir les mutations sociospatiales régionales en cours. En effet, malgré des bonnes intentions gouvernementales et internationales, le manque de concertation au niveau local et le manque de connaissance en hydro-écologie restent les contraintes majeures pour le succès de la protection environnementale et l’équité entre les populations concernées, deux conditions obligatoires à la durabilité des projets de barrages hydroélectriques. Pour conclure, il semble que le succès d’implantation d’un grand barrage hydroélectrique soit lié à la capacité des décideurs à comprendre les interactions complexes entre systèmes écologiques et systèmes socio-économiques. / The thesis project assumes that the construction of hydropower dams could be a driven force for a harmonious economic development between mountains and plains. The aim would be to link policies for hydropower dam development, and policies for agriculture in mountains, within individual strategies, in relationship with physical and socio-economic constraints. Since 2000’s, throughout Southeast Asia, many projects of large hydropower dams are built or being built to meet the strong growth in demand for energy, causing great threats to water management and the environment on the one hand, and imposing important population displacement on the other hand. In these mountainous regions, the erosion process is a major risk for both the filling of reservoirs and agricultural soil productivity. Then major investors, for the lifespan of hydropower dams, and small farmers, for their livelihoods, are equally impacted. The challenge is to reformulate the relationship between planning and management of hydropower dams, and planning and management of agricultural uplands in upstream areas of dams. Although the socio-economic support has been very much improved from the Vietnamese State, displaced and non-displaced farmers are still largely undergoing regional socio-spatial changes on-going. In spite of good government and international intentions, the lack of consultation at local level and the lack of knowledge in hydro-ecology remain major constraints to the success of environmental protection and equity between the concerned populations, two mandatory conditions for sustainability of hydroelectric dam projects. In conclusion, it appears that the successful implantation of a large hydroelectric dam is related to the ability of policymakers to understand the complex interactions between ecological and socio-economic systems.

No description available.

This thesis is primarily focused on flow-field upstream of hydropower intakes, with emphasis on the use of temperature control curtains and predicting the flow acceleration zone. By reviewing the available literature, it is concluded that the flow-field upstream of hydropower intake systems can be modeled by potential flow theory. The understanding of near intake flow-field can be useful in fish entrainment studies and in designing fish repulsion systems. To control downstream river temperatures, a flexible curtain was installed upstream of several dams in California. Flow downstream of the curtain was analyzed using a Computational Fluid Dynamic (CFD) solver with rigorous validation by experimental data. The experiment was conducted with a 4 beam Acoustic Doppler Velocimeter (ADV) probe. The study shows that wall jet properties downstream of the curtain are affected by the water depth and the inlet Reynolds number. Empirical expressions were developed to predict jet properties and the wall shear stress. Flow upstream of the curtain was analyzed using potential flow theories with validation by the CFD solver. In this part, a theory based on Schwarz-Christoffel transformation was developed to predict the flow-field upstream of the curtain without accounting for any density stratification in the water body. It is observed that the acceleration zone upstream of the curtain can be affected by sink opening size, its location and water depth. The effect of boundaries on flow upstream of a line sink and the interaction of multiple sinks were analyzed. The effect of stratification on a line sink is also analyzed. A theory is developed to predict the incipient withdrawal condition when a sink is located on the horizontal bottom. The theory is also extended to a tilted bottom. The effect of boundaries on the incipient withdrawal condition is analyzed. When only one layer is being withdrawn, it is shown that a homogenous equation can be applied to a stratified condition by assuming an upper layer boundary at the interface. In addition to these works, a despike algorithm for ADV data is developed, and a numerical analysis on central difference scheme is presented. / Water Resources Engineering

Nongovernmental organisations (NGOs) have come to play a major role in contemporary governance systems, and particularly in the fields of water and the environment. Adopting a new institutional theoretical perspective, this thesis examines how rules and norms affect the advocacy strategies of coalitions of NGOs in Vietnam and Cambodia, utilising a comparative case study analysis of the Xayaburi hydropower dam planned on the Mekong River in Laos. The comparison was conducted between the Rivers Coalition in Cambodia and the Vietnam Rivers Network during the planning period for the dams in 2011-2013.The main findings of the study is that rules, norms, actors, biophysical and material conditions interact with each other in creating influence over advocacy strategies. Different patterns of interactions were identified; these are 1) complementary interactions between formal rules, informal rules and norms 2) competing interactions between formal rules, informal rules and norms. Actors play important roles in both of these forms of interactions. Through identification of the barriers and opportunities NGO actors face within the Mekong region, the thesis concludes with two recommendations: 1) modifications to the formal rules which could facilitate further integration of NGOs and civil society actors into decision-making processes of transboundary water governance and 2) use of analytical framework by NGO and civil society actors in identifying windows of opportunities for advocacy strategies.

Förlorad biologisk mångfald är ett av de största hoten mot vår planet, och i sötvatten har populationer av migrerande fiskarter minskat med 76 % sedan 70-talet. Ålen är en art som hotas av utrotning på grund av antropogen inverkan, framför allt på grund av kraftverksdammar som fragmenterar habitat och förhindrar artens livsnödvändiga migration upp- och nedströms vattendrag genom avsaknad av passagelösningar. Syftet med studien var att undersöka möjligheten att vidareutveckla ålpassagelösningar med substratet EF-16, detta genom att testa klättringsframgången för glasålar vid två olika passageramper och två olika flöden (3 l/min och 9 l/min). Varje passagelösning bestod av fyra passageramper positionerade i bredd, med EF-16 monterat varannan ramp antingen rakt eller lateralt v-format. Resultatet från studien visade att de optimerade v-formade passageramperna gav signifikant fler klättringar vid höga flöden, samt att placeringen av ramperna också hade signifikant betydelse för valet av ramp. Kroppsvikten för ålar hade däremot ingen effekt för passageframgången. Denna studie betonar vikten av framtagandet av effektiva passagelösningar för glasålar som fungerar vid stora variationer av flöde vid kraftverksdammar. Genom att fler ålar kan migrera uppströms vattendrag förbi kraftverksdammar till sina uppväxtområden, kan förhoppningsvis ålstammen räddas. / Biodiversity loss is one of the biggest threats to our planet, and in freshwater, populations of migratory fish species have declined by 76% since the 1970s. The eel is a species threatened with extinction due to anthropogenic impact, mainly due to power plant dams that fragment habitat and prevent the species' vital migration up and down streams through lack of passage solutions. The purpose of the study was to investigate the possibility of further developing eel passage solutions with the substrate EF-16, by testing the climbing success of glass eels at two different passage ramps and at two different flows (3 l/min and 9 l/min). Each passage solution consisted of four passage ramps positioned widthwise, with EF-16 mounted either flat or lateral v-shaped every other ramp. The study shows that the optimized v-shaped passage ramps gave significantly more climbs at high flows, and that the location of the ramps also had a significant impact on the choice of ramp. The body weight of eels, on the other hand, had no effect on passage success. This study emphasizes the importance of the development of efficient passage solutions for glass eels that can be applied at large variations in flow at power plant dams. By allowing more eels to migrate upstream watercourses past hydropower plants to their spawning grounds, the eel population can hopefully be saved. / Optimerade passagelösningar för ål, 52096-1