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Ce travail a été effectué dans le cadre d’une convention de cotutelle entre les Universités de Corse et d’Antananarivo. Il a contribué à la caractérisation de cinq Plantes de Madagascar à travers la composition chimique de leurs huiles essentielles (HE). Quatre plantes aromatiques et médicinales (Cymbopogon giganteus var. madagascariensis, Tana bojeriana, Croton kimosorum et Croton sp.) poussent à l’état spontané dans la région sub-aride du sud-ouest de Madagascar (Toliara) alors que l’espèce Vepris madagascarica est présente dans la forêt dense humide du nord-est (Vohémar). Ainsi, nous avons étudié par combinaison CPG (IR), CPG-SM et RMN 13C la composition chimique d’huiles essentielles obtenues par hydrodistillation (appareil type Clevenger) et par entraînement à la vapeur d’eau (Alambic).Les huiles essentielles de Cymbopogon giganteus Chiov. var. madagascariensis (A. Camus) ou Ahibero possèdent une composition chimique comparable avec celles des espèces Cymbopogon giganteus Chiov. africaines décrites dans la littérature. Elles sont dominées par les quatre menthadiénols (cis- et trans-p-mentha-1(7),8-dièn-2-ol, cis- et trans-p-mentha-2,8-dièn-1-ol) et le limonène. Nous avons aussi identifié quatre hydropéroxydes possédant le squelette p-menthane. Une monographie de l’huile essentielle d’Ahibero a été proposée à l’intention des utilisateurs de cette huile essentielle.La composition chimique de l’HE de Tana bojeriana Baker est caractérisée par la présence majoritaire de l’-phellandrène (30,4%), de la carvone (22,3%), du limonène (13,3%) et du dill éther (7,7%). Cette composition chimique apparait très proche de celle d’Anethum graveolens (Apiaceae). La présence du trans-p-menth-2-èn-1,6-diol et du p-mentha-1(7),2-dièn-6-ol lui confère une certaine originalité Elle pourrait donc constituer une alternative aux huiles essentielles qui sont bien implantées sur le marché des Plantes Aromatiques et Médicinales (PAM).La composition chimique de l’HE de feuilles de Vepris madagascarica (Baill.) H. Perrier est caractérisée par une très forte teneur en (E)-anéthole (78,2%). L’étude comparative de la composition chimique des huiles essentielles de feuilles (fraîches et séchées) et d’écorces de tronc confirme la prédominance du (E)-anéthole (69,5 à 84,6%). Compte tenu de la répartition restreinte de cette plante aromatique et en vue d’une gestion durable de cette espèce, son exploitation devrait être limitée aux huiles essentielles des feuilles qui pourraient ainsi constituer une source de (E)-anéthole, composé très utilisé en agro-alimentaire.Deux espèces de Croton endémiques de Madagascar ont été étudiées, Croton kimosorum Leandri (Zanapoly ou Napoly) et Croton sp. (Andriambolamena ou Riamena). Les huiles essentielles de ces deux plantes aromatiques et médicinales sont caractérisées par la présence du linalol (Zanapoly) et du limonène(Andriambolamena). La première HE est caractérisée par une majorité de composés oxygénés tandis que la seconde est dominée par les composés oléfiniques monoterpéniques. Dans les deux cas, de nombreux sesquiterpènes oxygénés ont été identifiés. Parmi eux, l’épi--bisabolol, jamais décrit dans une HE du genre Croton, est trouvé pour la première fois dans les deux espèces. / This study was conducted under an agreement of co-supervision between the Universities of Antananarivo (Madagascar) and Corsica (France). It contributed to the characterization of five malagasy plants through the chemical composition of their essential oils (EO). Four aromatic and medicinal plants: Cymbopogon giganteus var. madagascariensis, Tana bojeriana, Croton kimosorum and Croton sp. grow wild in the south-western region of Madagascar (Toliara) whereas the species Vepris madagascarica is widespread in the rainforest of the north-eastern region (Vohémar). The identification of components of EOs produced by hydrodistillation (Clevenger type apparatus) and by steam distillation (Alembic) has been obtained by combination of GC (RI), GC-MS and 13C NMR.Cymbopogon giganteus Chiov. var. madagascariensis (A. Camus) EO or Ahibero EO of Madagascar has similar chemical composition with Cymbopogon giganteus Chiov. african species described in literature. Its chemical composition is dominated by four p-menthadienols (cis- and trans-p-mentha-1(7),8-dien-2-ol, cis- and trans-p-mentha-2,8-dien-1-ol) and limonene. Moreover, four peroxides derivatives bearing the p-menthane skeleton were also identified. A monography has been proposed to Ahibero EO users.Tana bojeriana Baker EO is characterized by the predominance of -phellandrene (30.4%), carvone (22.3%), limonene (13.3%) and dill ether (7.7%). The chemical composition of this EO was very close to that of Anetum graveolens (Apiaceae family), constituents. The presence of trans-p-menth-2-en-1,6-diol and p-mentha-1(7) ,2-dien-6-ol, gives some originality to Tana bojeriana EO. It could be therefore an alternative for essential oils that are already well established on the Medicinal and Aromatic Plants market.The chemical composition of Vepris madagascarica (Baill.) H. Perrier leaf EO is characterized by a high content of (E)-anethole (78.2%). The comparative study of the chemical composition of leaves (fresh and dried) and bark trunk EOs confirmed the predominance of (E)-anethole (69.5 to 84.6%). Taking account of the restricted distribution of this aromatic plant and the need for sustainable management of this species, its potential use would be limited to leaf oil and could be a source for this compound widely used in food industry.Two species of Croton endemic from Madagascar were studied, Croton kimosorum Leandri (Zanapoly or Napoly) and Croton sp. (Andriambolamena or Riamena). Both aromatic and medicinal plants EOs are characterized by the presence of linalool (Zanapoly) and limonene (Andriambolamena). Croton kimosorum is characterized by a majority of oxygenated compounds, while the second is dominated by hydrocarbon monoterpenes. In both cases, several oxygenated sesquiterpenes are identified. Among these, the epi--bisabolol, never reported in of Croton EOs, was found for the first time in both species.

Frequent climatic shocks have presented challenges for rainfed agriculture in sub-Saharan Africa. Appropriate water management practices are among the solutions to the challenges. The role of water harvesting in achieving sustainable agricultural intensification and specified resilience was explored. Suitable areas for water harvesting in the Upper Blue Nile basin were identified. The usefulness of the Curve Number method for surface runoff estimation was evaluated, and was found to perform satisfactorily. The impact of climate change in the Lake Tana sub-basin was studied. A decision support system was developed for locating and sizing of water harvesting ponds in the SWAT model. Methodological developments enabled analysis of the implications of water harvesting intensification in a meso-scale watershed in the Lake Tana sub-basin. Results suggest that water harvesting can increase agricultural productivity, sustain ecosystems and build specified resilience, and thereby contribute to sustainable agricultural intensification. There is considerable potential for water harvesting in the Upper Blue Nile Basin. Rainfall may increase in the Lake Tana sub-basin due to climate change. Supplementary irrigation from water harvesting ponds and better nutrient application increased staple crop production by up to three-fold. Moreover, a substantial amount of cash crop was produced using dry seasonal irrigation. Water harvesting altered the streamflow regime, and reduced sediment loss from the watershed.       Water harvesting can play an important role in food security. It showed potential to buffer climatic variability. In the watershed studied, water harvesting will not compromise the environmental water requirements. Instead, increased low flows, and reduced flooding and sediment loss may benefit the social-ecological systems. The adverse effects of disturbance of the natural flow variability and sediment influx to certain riverine ecosystems warrant detailed investigation. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript. Paper 5: Epub ahead of print. Paper 6: Manuscript.</p> / Water resources management and social-ecological resilience

Cette étude a été menée dans le bassin versant du lac Tana situé dans le haut bassin du Nil Bleu en Ethiopie, où les enjeux liés à l'exploitation des ressources en eau sont critiques et la disponibilité de données pertinentes est faible. L'étude est divisée en trois parties principales qui comprennent l'évaluation de la qualité et l'analyse des données existantes, l'évaluation de l'applicabilité d'un modèle hydrologique à base physique et le calcul des bilans en eau et des matières en suspension du lac Tana. Les couvertures spatiales et temporelles des variables hydro-météorologiques ont été évaluées à partir des méthodes recommandées dans la littérature. L'analyse des jeux de données hydro-météorologiques comprend le contrôle de la qualité des données, et la détermination de leurs caractéristiques spatiales et temporelles. L'applicabilité du modèle hydrologique à base physique a été évaluée sur deux bassins versants. Cet exercice de modélisation a montré l'intérêt des méthodes de désagrégation temporelle pour générer des données météorologiques à des échelles de temps plus courtes. Compte tenu de la qualité des données utilisées, la performance du modèle dans deux des bassins versants a été jugée satisfaisante. Le bilan en eau du lac Tana a été calculé au pas temps mensuel ce qui a impliqué l'estimation des différents termes. Un modèle dynamique et conceptuel a été utilisé pour estimer les contributions des bassins versants pour lesquels les données hydrométriques sont manquantes. Les résultats du calcul sont généralement bons et les niveaux observés du lac sont reproduits de manière satisfaisante. L'estimation du bilan des matières en suspension pour le lac a nécessité le développement et l'utilisation des courbes débit-concentration et un modèle régional. Les résultats présentés dans ce travail sont utiles pour la planification et la gestion des ressources en eau dans cette région d'Ethiopie.

Lake Tana Basin is of significant importance to Ethiopia concerning water resources aspects and the ecological balance of the area. The growing high demands in utilizing the high potentials of water resource of the Lake to its maximal limit, pictures a disturbing future for the Lake. The objective of this study was to assess the influence of topography, soil, land use and climatic varia-bility on the hydrological and hydrodynamic processes of the Lake Tana Basin. The physically based SWAT model was successfully calibrated and validated for flow and sediment yield. Se-quential uncertainty fitting (SUFI-2), parameter solution (ParaSol) and generalized likelihood un-certainty estimation (GLUE) calibration and uncertainty analysis methods were compared and used for the set-up of the SWAT model. There is a good agreement between the measured and simulated flows and sediment yields. SWAT and GIS based decision support system that uses multi-criteria evaluation (MCE) was used to identify the most vulnerable areas to soil erosion in the basin. The results indicated that 12 to 30.5% of the watershed is high erosion potential. Pro-jected changes in precipitation and temperature in the basin for two seasons were analyzed using outputs from fifteen global climate models (GCMs). A historical-modification procedure was used to downscale large scale outputs from GCM models to watershed-scale climate data. The results showed significant changes in streamflow and other hydrological parameters in the period between 2045-2100. SWAT was combined with a three dimensional hydrodynamic model, GEMSS to investigate the flow structure, stratification, the flushing time, lake water balance and finally the Lake‘s water level response to planned water removal. We have found an alarming and dramatic fall of the water levels in Lake Tana as response to the planned water withdrawal. The combination of the two models can be used as a decision support tools to better understand and manage land and water resources in watersheds and waterbodies. The study showed that the Lake Tana Basin may experience a negative change in water balance in the forthcoming decades due to climate change as well as over abstraction of water resources. / QC 20100720

In these days environmental issues are critical. Environmental concerns mainly rise from energy productions. Fortunately Ethiopia is trying to use renewable energy sources as a means for electrical power production and it is a great start for a long, tiresome green energy journey. The basic job to be done in green energy sectors is to maximize the capacity of renewable technologies to fulfil the best efficiency.  Intermittent nature of the energy production and their inefficiency to meet peak load demands are the basic problems in renewable energy sectors.   Ethiopia’s electrical power production is mainly dependent on hydropower; according to latest data from EEPCO hydro covers 88% of the total production. There are two major nature of this power plant; since the working medium is water it is mainly dependent on the nature of the seasons and secondly it rarely meets peak load demands. After the erection of the power plant the energy production is not time dependent; it can produce power continuously; but the consumption is time dependent which is defined as peak hours and off-peak hours. There is excess load in time of off-peak hours and scarcity in peak hours. So this work can help to maximize the capacity of the water for production by using technological advancements to produce lot of energy in almost full capacity throughout the year to full fill the need of our country. Tana Beles hydropower plant is the largest hydropower plant which starts to work in May, 2010 with an investment cost of $500 million and capacity of 460 MW. The project is planted in Amhara region using the water source of Lake Tana. To make this large and very necessary renewable energy resource sustainable using energy storage system will be vital. This study will figure out a pumped storage system for the hydropower plant for additional power production and for the sustainability of the water resource.    Pumped storage system is the only viable, large-scale resource that is being broadly utilized today for storing energy, and it offers the best option available for harnessing off-peak generation from renewable sources. The contributions of pumped storage hydro to our nation’s transmission grid by providing stability services, storage capacity needs, and expanding the green job market are considerable today.   The high energy demand of the pump will be considered to be covered using the excess electrical power production during night or weekends and if the resource is available using wind solar PV hybrid systems.   The author will try to assess the technology not only for other mini hydro power plants but also for irrigation and other purposes merely in Amhara region, Ethiopia. The feasibility of the system will be considered technically and economically for the hydropower plant.

<p>Land and water resources degradation are the major problems on the Ethiopian highlands. Poor land use practices and improper management systems have played a significant role in causing high soil erosion rates, sediment transport and loss of agricultural nutrients. So far limited meas-ures have been taken to combat the problems. In this study a physically based watershed model, SWAT2005 was applied to the Northern Highlands of Ethiopia for modelling of the hydrology and sediment yield. The main objective of this study was to test the performance and feasibility of SWAT2005 model to examine the influence of topography, land use, soil and climatic condi-tion on streamflows, soil erosion and sediment yield. The model was calibrated and validated on four tributaries of Lake Tana as well as Anjeni watershed using SUFI-2, GLUE and ParaSol algo-rithms. SWAT and GIS based decision support system (MCE analysis) were also used to identify the most erosion prone areas in the Lake Tana Basin. Streamflows are more sensitive to the hy-drological response unites definition thresholds than subbasin discretization. Prediction of sedi-ment yield is highly sensitive to subbasin size and slope discretization. Baseflow is an important component of the total discharge within the study area that contributes more than the surface runoff. There is a good agreement between the measured and simulated flows and sediment yields with higher values of coefficients of determination and Nash Sutcliffe efficiency. The an-nual average measured sediment yield in Anjeni watershed was 24.6 tonnes/ha. The annual aver-age simulated sediment yield was 27.8 and 29.5 tonnes/ha for calibration and validation periods, respectively. The SWAT model indicated that 18.5 % of the Lake Tana Basin is erosion potential areas. Whereas the MCE result indicated that 25.5 % of the basin are erosion potential areas. The calibrated model can be used for further analysis of the effect of climate and land use change as well as other different management scenarios on streamflows and soil erosion. The result of the study could help different stakeholders to plan and implement appropriate soil and water conser-vation strategies.</p>

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Ce mémoire se penche sur le processus identitaire de la deuxième génération d’Italo-Québécois lors de la deuxième vague migratoire. Plus précisément, nous porterons notre regard sur les œuvres de créations de Marco Micone, Mary Melfi et Paul Tana afin de dévoiler certains aspects de l’identité qui sont dissimulés à travers la fiction. C’est à travers leur vision qu’il sera possible de dégager plusieurs trames narratives qui relatent différentes trajectoires migratoires et d’établissement au Québec, tout en exposant le défi de se (re)définir relativement à la multiplication des référents dans une société moderne et bilingue. Si c’est la deuxième génération qui fait office de protagoniste dans ce mémoire, cela s’explique par le statut qu’elle occupe dans la société québécoise et les changements auxquels elle se confronte. Au lieu de définir une identité globale, nous nous intéressons davantage aux éléments qui façonnent, qui affectent, mais surtout qui font pression sur la (re)définition identitaire de cette génération. À la lecture des sources constituant ce mémoire, trois grandes thématiques sont apparues comme des éléments modélisateurs de l’identité pour la deuxième génération d’Italo-Québécois. Il s’agit de la relation au(x) langue(s), les rapports de genre et la dynamique intergénérationnelle. Celles-ci sont abordées par chacun des créateurs, bien que de manières différentes. Ceci renforce l’idée qu’il est impossible de parler d’une identité italo-québécoise commune et qu’il est préférable de parler d’identités italo-québécoises. En définitive, il s’agit de montrer en quoi la littérature et les œuvres de création nous amènent à repenser l’établissement des Italiens au Québec. / This thesis focuses on the process of identity formation of second generation Italo-Quebeckers during the second wave of migration. More precisely, it looks at the creative works of Marco Micone, Mary Melfi and Paul Tana in order to reveal certain aspects of identity that are contained in works of fiction. It is through their vision that it is possible to identify several narrative frames that underscore different migratory and settlement trajectories in Quebec. These visions also expose the challenge of the (re)definition of self in a modern and bilingual society. Instead of defining a “global” identity, this thesis is more interested in the elements that shape, affect, and above all, put pressure on the (re)identification of this generation. Drawing upon the sources employed in this thesis, three main themes emerge as modelling elements of identity for the second generation of Italo-Québécois: the relationship to language(s), gender relations, and intergenerational dynamics. All these themes are explored by each of the creators, although in different ways. This reinforces the idea that it is impossible to talk about a common Italian-Québécois identity and that it is preferable to talk about Italian-Quebecois subjectivities. Ultimately, it is a matter of disclosing how literary and creative works encourage us to rethink the establishment of Italians in Quebec, as well as their vision of Quebec society.

Land and water resources degradation are the major problems on the Ethiopian highlands. Poor land use practices and improper management systems have played a significant role in causing high soil erosion rates, sediment transport and loss of agricultural nutrients. So far limited meas-ures have been taken to combat the problems. In this study a physically based watershed model, SWAT2005 was applied to the Northern Highlands of Ethiopia for modelling of the hydrology and sediment yield. The main objective of this study was to test the performance and feasibility of SWAT2005 model to examine the influence of topography, land use, soil and climatic condi-tion on streamflows, soil erosion and sediment yield. The model was calibrated and validated on four tributaries of Lake Tana as well as Anjeni watershed using SUFI-2, GLUE and ParaSol algo-rithms. SWAT and GIS based decision support system (MCE analysis) were also used to identify the most erosion prone areas in the Lake Tana Basin. Streamflows are more sensitive to the hy-drological response unites definition thresholds than subbasin discretization. Prediction of sedi-ment yield is highly sensitive to subbasin size and slope discretization. Baseflow is an important component of the total discharge within the study area that contributes more than the surface runoff. There is a good agreement between the measured and simulated flows and sediment yields with higher values of coefficients of determination and Nash Sutcliffe efficiency. The an-nual average measured sediment yield in Anjeni watershed was 24.6 tonnes/ha. The annual aver-age simulated sediment yield was 27.8 and 29.5 tonnes/ha for calibration and validation periods, respectively. The SWAT model indicated that 18.5 % of the Lake Tana Basin is erosion potential areas. Whereas the MCE result indicated that 25.5 % of the basin are erosion potential areas. The calibrated model can be used for further analysis of the effect of climate and land use change as well as other different management scenarios on streamflows and soil erosion. The result of the study could help different stakeholders to plan and implement appropriate soil and water conser-vation strategies. / QC 20101123