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Energy is an essential factor regarding the economic development and for providing a high standard of living to the population of any country. Because energy is produced mainly using classic fuels (coal, oil and gas) for a few decades there are signals regarding their exhaustion. Therefore, mankind should concern more about finding viable alternatives to replace the classical fuels. This way the use of nuclear fuels appeared, then the force of the wind, of the tides and of the photovoltaic cells. However, there are still enough energy resources for further growth of the global energy production. The great consumers are both the major energy producers, only their hierarchy has changed and changes over time. The paper presents all these countries, and also Romania, including its specific developments in recent years.

Les grandes caractéristiques hydrobiologiques du bassin de Marennes-Oléron sont définies par quatre campagnes saisonnières de 120 prélèvements chacune effectuée-, en 15 stations en demi-cycle de marée. Les salinités y fluctuent de 10 '/rr. et ce secteur peut donc être assimilé à un vaste estuaire contrôlé principalement par les apports fluviaux de la Charente. La turbidité reste élevée souvent supérieure à 100 mg.I"', les teneurs en oxygène dissous montrent un déficit en amont de la Charente et de la Seudre de 4 mg.L1 tandis que les sels nutritifs sont apportés par la Charente pour les nitrates, phosphates et silicates. Ces derniers suivent les courbes de dilution théorique excepté lors des poussées phytoplanctoniques et lors des crues hivernales. Lors de ces crues, les nitrates semblent soit apportés par la Gironde, soit dus à une minéralisation organique. Au même moment, les phosphates pourraient être absorbés sur les particules et être piégés dans les sédiments. Les biomasses phytoplanctoniques exprimées par les teneurs en chlorophylle a sont supésieures à 30 f^-g.1 ' en amont des estuaires au printemps avec des teneurs en phéopigmenls pouvants dépasser 200 IUJ.1 . par contre, dans le bassin, les teneurs ne dépassent guère 10 fig.l ''. Les concentrations en ATP montrent que peu de phytoplancton est physiologiquement actif en particulier dans les estuaires, tandis que les dosages de protéines permettent de quantifier la part des apports allochtone - par rapport à la production autochtone des estuaires. Line analyse factorielle des correspondances définit le schéma général hydrobiologique du bassin estuarien en précisant que 'e rôle de la Charente ne se limite pas à l'apport en sels minéraux azotés et phosphatés, mais aussi à l'apport d'une biomasse phytoplanctonique d'eau douce en voie de dégénérescence. Les auteurs proposent qu'une nouvelle stratégie d'échantillonnage, mieux adaptée aux objectifs recherchés, soit suivie ultérieurement en assurant des prélèvements en cycle de marée mais avec une périodicité la plus élevée possible. Four seasonal compaigns providing a sampling of 15 stations each followed during half a tide cycle, i.e. 120 water samples permit the definition of the main hydrobiological features of Marennes-Oleron Bay: salinity and turbidity, phytoplanktonic biomasses, ATP concentrations. The authors suggest that a new way of adapted sampling to their objectives, will work out in the future by sampling during tidal cycles but as frequently as possible.

[Paper in French] The European public policy in favor of the biodiesel consumption is highly debated. Available estimates of the induced land use changes conclude that this policy is inefficient to reduce emissions of GreenHouse Gas. We show that the crop yield evolutions in these estimates are significantly lower than the observed and expected evolutions. This difference is directly related to biased calibration choice of behavioral parameters. We show using the GTAP-BIO framework that a consistent calibration of these parameters leads to a strong reduction (by around 80% in the long run) of the land use changes and induced emissions.

Existe-t-il un consensus scientifique sur les conditions de la durabilité ?Est-il possible de construire un indicateur unique de soutenabilité faible ?Quelles sont les composantes objectives et subjectives des indicateurs ?Peut-on envisager des indicateurs objectifs de soutenabilité ?Quelles voies de recherche sont-elles nécessaires pour développer des indicateurs de développement durable ?Telles sont les questions auxquelles cet ouvrage tente de répondre.La comparaison des courants de la soutenabilité faible et de la soutenabilité forte nous sert de fil conducteur pour évaluer la part normative et la part objective du choix des paramètres et de leur méthode d'agrégation. L'agrégation arithmétique implique des hypothèses de substituabilité entre les facteurs, ce qui relève de la soutenabilité faible. La pondération, toujours normative, peut être explicite ou se traduire par le choix d'une unité ou dimension unique. Nous redéfinissons la soutenabilité faible comme étant la réduction de la complexité à une dimension unique. Il y a dès lors autant d'indicateurs de soutenabilité faible que de choix possibles de cette dimension unique. En particulier, l'empreinte écologique par habitant relève d'une forme "écologique" de soutenabilité faible. Le prix de marché est l'unité fondamentale de mesure de sa forme "économique". Nous montrons que les acteurs ne savent pas bien identifier leur intérêt et qu'ils ne sont pas parfaitement égoïstes, ce qui introduit un biais non systématique remarquable dans toute mesure en unité monétaire. La soutenabilité forte se caractérise par la multiplicité de dimensions ou "capitaux critiques" dont le dépassement d'un seul suffit à déterminer la non soutenabilité. Les différentes formes de soutenabilités faibles peuvent représenter des capitaux critiques parmi d'autres.Nous présentons une typologie des acteurs et du partage des responsabilités, également susceptible d'introduire des grandes divergences dans les résultats publiés. Quelques études de cas illustrent ces différents éléments dans des contextes contrastés. L'empreinte écologique de consommation se limite en particulier à une responsabilisation du seul consommateur, alors que les comptes nationaux permettent d'envisager la coresponsabilité de l'ensemble des acteurs. L'indicateur de "dématérialisation de l'économie" appliqué à un village indien montre la pertinence de mesurer l'utilisation absolue de matière sans pondération monétaire. Il est par ailleurs possible de minimiser le coût de dépollution sans toucher à la limite absolue d'émissions globales de centrales thermiques. Les deux dimensions, coûts sociaux et bénéfices environnementaux, peuvent donc être traitées séparément.En conclusion, il est possible d'identifier, dans chaque calcul d'indicateur de développement durable, une composante relativement objective de soutenabilité "forte" et une composante "faible", négociable, de partage des droits et responsabilités./ We study how different world views may influence how to develop sustainable development indicators. The comparison of weak sustainability and strong sustainability serves as a guide to estimate the share of objective versus normative choice of parameters and their method of aggregation. We then present a typology of actors and shared responsibilities, which may also introduce large discrepancies in the results published. Some case studies illustrate these different elements in contrasting contexts. It appears that it is possible to identify in each calculation of sustainable development indicator, a relatively objective component of sustainability and a negotiable component of shared rights and responsibilities. info:eu-repo/semantics/nonPublished Doctorat en Sciences

Climate change will affect agricultural production conditions, which will translate in impacts on yield and cost of production for Quebec farmers. This would likely affect the relative competitive position of Quebec in North America. Using the Delphi technique and partial budgets, climate change scenarios for the 2050 period were elaborated and their impact on relative competitiveness assessed for Quebec and its competitors in North America. Results indicate that Quebec competitive position would improve due to more favorable conditions for corn and apple production and due to worsen conditions for the competitors in maple syrup production.

Nutrient analyses were done in melted ice, frazil and sea water of the upper part of the water column, where as major constitutive elements of micro-algae were analysed. Measurements of nutrient uptake were carried out with frazil algae incubated at -1.5 degree C in a field incubator. Differential-enrichment bioassays and mean N/P ratio (5.9) demonstrated that actual growth of the cultures was nutrient-limited. Nitrogen governed the algal yield when illumination and grazing allowed the microalgae to grow. It concluded that the epontic dynamics is not only controlled from above, by the seasonal (climatic) changes in light intensity as generally assumed, but also from below, by the short-term (hydrodynamic) events of vertical mixing that replenish the ice-water interface in nutrients.

This thesis aims to examine the causal mechanisms of living environments on leisure mobilities and verify whether their inclusion is actually able to challenge the compact city as a sustainable urban form. The research focuses on the Swiss case and in particular the cities of Geneva and Zurich. The empirical approach is based on three types of additional analysis carried out in these areas: contextual analysis, quantitative analyzes based on data from the Mobility and Transport Microcensus 2010 and qualitative analysis through interviews. The main results are the following: â ¢ We find the existence of two opposing logics of association between land density and distance traveled: a decreasing link to daily mobility, but a positive correlation for occasional mobility (day trips and overnight trips). The denser is the living environment, the greater is the distance for this mobility. â ¢ Adding the two types of mobility to obtain a total average, we find that the inner city dwellers displayed, ultimately, much higher totals than would suggest the analysis of their daily mobility alone which therefore represent an invitation to invalidate the link compact city=short distances. â ¢ By transforming these distances into environmental impact, however, our calculations show that even while taking into account the many trips of urban dwellers, the negative relationship between total energy consumption and land density of the territory remains. â ¢ By examining in detail the share of leisure in daily and occasional mobility, we see that the logic of compensation is not what structures the links with urban environnements. In everyday life, the logic of proximity prevails: to live in the centre is rather correlated to more compactophile leisure and residing in the periphery to more leisure oriented towards the attributes of nature. â ¢ For occasional trips, we show firstly that compactophile mobilities represent a large part of these practices among all respondents, and secondly, that even in the case of very important and high energy consuming naturophile mobility, the relationship with the density of the living environment is not established. The central Genevans and are much less consumers of this type of leisure than people in the centre of Zurich even though their city is much more airy and green. Moreover, we also highlight, in peri-urban dwellers, a very intense mobility or this purpose. â ¢ The interpretation that we propose refers to lifestyles and residential choice of city dwellers which takes into account their leisure aspirations. These tastes are then translated into specific leisure activities and travel. In everyday life, they rely on proximity and functional, social and sensitive attributes of their living environment that they have chosen largely also for this. When it comes to breaking the routines during holidays and vacations, the same lifestyles result in significant occasional mobility whose motives can register in continuity of their daily lifestyle (loving the same things elsewhere) or by contrast (appreciate the diversity of spaces). In both cases, these motivations echo the valorisation of the diversity inherent in urbanity without questioning the urban residential location quality itself. Our results lead us ultimately to reject the compensation effect hypothesis and reaffirm, against the defenders of the sprawl-city, the virtues of the compact city, which remains a sustainable urban form, including for our leisure mobility.

Income source and accompaniment needs of family farms in the cotton growing area of West Burkina Faso Description of the subject. In the western cotton growing area of Burkina Faso, the variability and the diversity of the income levels of family farms (EAFs) mean that these farms require suitable agronomic accompaniment. Objectives. This article gives an account of this diversity and the need for accompaniment according to the type of identified EAF.Method. The data were collected by the active method of participative research and by investigation of the practices of 120 farms in the commune of Koumbia. Principal component analyses with economic indicators of the EAF were applied, followed by an ascending hierarchical clustering. The structural characteristics, the agro-pastoral practices of production, and the perceptions of the EAF regarding the constraints and appropriateness of agricultural production were compared by variance analysis. Results. The results showed three types of farm: farms with a low-income culture (farmers with few animals), those with a high income culture (farmers with a large number of animals) and those deriving income from breeding (stockbreeders). Taking into account the structure of the farms, their production practices, their technico-economic performance and their appropriateness of agricultural production, the form of sustainable accompaniment needed may be identified in relation to several common or specific innovations of the identified farm types. Accompaniments in the case of farm stock management, and good practice in the management of soil fertility and of animals were common to the three types of EAF. The fodder culture, fattening on pasture and the method of dairy production were specific to the farmers with a large number of animals and to the stockbreeders. The improvement of the food value of culture residues and of some aspects of the maintenance of oxen were more appropriate to the farmers with few animals. Conclusions. In order to succeed, the process of accompaniment must take into account both these specificities and the concept of sustainability. Description du sujet. Dans la zone cotonnière ouest du Burkina Faso, la variabilité et la diversité des revenus des exploitations agricoles familiales (EAF) demandent pour ces dernières des accompagnements appropriés. Objectifs. Cet article rend compte de cette diversité et des besoins d’accompagnement selon les types d’EAF identifiés.Méthode. Les données ont été collectées par la méthode active de recherche participative et par enquête auprès d’un échantillon raisonné de 120 exploitations dans la commune de Koumbia. Une analyse en composante principale avec des indicateurs économiques de l’EAF suivie d’une classification ascendante hiérarchique ont été appliquées. Les caractéristiques structurelles, les pratiques de production agro-pastorales, les perceptions des chefs d’EAF sur les contraintes et opportunités de production agropastorale ont été comparées par une analyse de variance.Résultats. Les résultats montrent trois types d’exploitations : les exploitations à faible revenu culture (agriculteurs), à fort revenu culture (agro-éleveurs) et à revenu élevage (éleveurs). À la lumière de leurs structures, pratiques de production, performances technico-économiques et opportunités de production agricole, leur accompagnement peut porter sur plusieurs innovations durables communes ou spécifiques des types identifiés. Des accompagnements sur la gestion des ressources de l’exploitation, les bonnes pratiques de gestion de la fertilité des sols et des animaux sont communs aux trois types d’EAF. Les cultures fourragères, l’embouche et la production laitière sont spécifiques aux agro-éleveurs et éleveurs. L’amélioration de la valeur nutritive des résidus de cultures et l’entretien des bœufs de trait conviennent plus aux agriculteurs.Conclusions. Pour réussir, le processus d’accompagnement doit prendre en compte ces spécificités et la notion de durabilité.

Metadata only record This document presents an analysis of Fulani pastoral farming systems that focuses on how pastoralists use silvopastoral land. It aims to provide the missing knowledge needed to implement the resource management ('gestion des terroirs') approach at village level. In this region the influence of pastoral land use on the environment appears to be less pronounced than that of crop cultivation, even though levels of animal production are reasonable. The carrying capacity of the region has not yet been attained. Current constraints to pastoral land use in the region arise from the encroachment of cropland at the expense of pastoral land, and the increase in animal numbers. To develop sustainable natural resource management at village level that includes Fulani pastoral land use, the key factors appear to be the integration of livestock husbandry and cropland cultivation at household level, agreements between pastoralists and cropland farmers on land tenure and resource management, and support targeting of Fulani households (which have so far been neglected). Specific recommendations are given. (CAB Abstract)