Dissertations / Theses on the topic 'Conditions écologiques'
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Ivanoff, Guennady. "Les conséquences écologiques de la gestion économique soviétique." Aix-Marseille 1, 1990. http://www.theses.fr/1990AIX10034.
Durantin, Gautier. "Contrôle de l’état attentionnel en conditions aéronautiques écologiques par imagerie cérébrale." Thesis, Toulouse, ISAE, 2015. http://www.theses.fr/2015ESAE0021/document.
The attentional state of operators is one of the main reasons for errors during human control of complex systems, and controlling these errors is critical especially in aeronautics, where errors are directly linked to safety and lives might be at stake. In particular, excessively high or low task demands encountered during the operation of such systems result in varying levels of mental workload and engagement which are linked with the operator performance. This research project adopts a Neuroergonomics approach and investigates the use of brain measurement techniques to monitor the attentional state of the operator under ecological conditions. We studied the behavior of the operator under both excessively low and high task demands with the use of multiple physiological and neurophysiological measurement techniques. Our results show that it is possible to use such techniques to characterize the attentional state. We then analyze the potential of real time application for such techniques. We investigated signal processing and analysis tools to improve the real-time usability of brain signals in ecological conditions, and proposed solutions towards the development of brain computer interfaces for assisting the human operator
Albera, Dionigi. "L'organisation domestique dans l'espace alpin : équilibres écologiques, effets de frontières, transformations historiques." Aix-Marseille 1, 1995. http://www.theses.fr/1996AIX10001.
This work is an attempt at a comparative study of the domestic organization within the alpine domain. The first part is concerned with a discussion of a number of epistemological and methodological issues related to the development of the interdisciplinary field of the "family history". The second part is devoted to an ethnographic and historical analysis of a valley of the piedmontese alps (italy). Through this micro-analytical focus, various chapters discuss the received wisdom ol alpine "family forms". A rethinking of quantitative methods, eco-demographic models and le play's categories goes along with the sketch of an ideal-typical approach. This analytical tool is developed in the comparative exploration which occupies the third part, where the data stemming from a number of ethnographic and historical researches carried on in the alps are examined by means of an interpretative reading
Bonenfant, Michèle. "Le strophaire : caractérisation de souches et influences de certaines conditions écologiques sur sa fructification." Rennes 1, 1993. http://www.theses.fr/1993REN10107.
Chabbi, Abad. "Conditions écologiques et dynamique de la végétation : basses montagnes du Rif occidental au Maroc." Bordeaux 3, 1994. http://www.theses.fr/1994BOR30035.
The subject of this study ecological conditions of the growing stock in the low mountains of the occidental rif in morocco. Cork oak (quercus suber) is the species of these woodlands. The regressive dynamics of the vegetation was of major interest. In the past, these cork oak were subject to a management project, which was never finished for reasons of accessibility and finance. Today the degradation of the rif area is a big ecological problem. During 4 years of investigation we dealt with the role of climatic and pedological conditions and particularly with the relation between plant species and ecological variables, using of "factor analyses of correspondances" (f. A. C. ). Further anthropological and sociopolitical factors were taken into account. Important remarks have been made concerning the impact of fire not only on group dynamics but also on mortality and burning losses. The speed of stand types regression was measured by examination of two aireal photographs, which were taken within a scope of 20 years. Finally the development of an original synthesis of photographic materiel out of superposition of cartographic material became possible. It shows the regressive dynamics of the three growing stocks of ahl serif, beni issef and soumata. During this study it became apparent that there is not equilibrium between the vegetation and its environmental factors. The vegetation is not at its climax. In fact, the low mountains of the occidental rif have suffered since many ages from degradation as a result of cutting and burning due to cultivation and pasture. We note that the witnesses of the ancient landscape have been registered by the soil profiles and underlined by the presence of characteristic species. By this study we want to attract the attention of the. .
Griveaud, Clémentine. "Influence des conditions écologiques sur la composition isotopique (δ13C, δ18O) du test de foraminifères benthiques actuels." Phd thesis, Université d'Angers, 2007. http://tel.archives-ouvertes.fr/tel-00345812.
Dieng, Alioune. "Impacts des politiques agricoles sur l’offre céréalière au Sénégal de 1960 à 2003 : évaluation à partir d’un modèle d’analyse statistique par zones agro-écologiques." Dijon, 2006. http://www.theses.fr/2006DIJOE009.
The purpose of this thesis was to estimate and to determine the impacts of the agricultural policies on the cereal supply in the long-run-period by agro-ecological zones. The description of the historical, quantitative and institutional elements caracterized the different agricultural policies since 1960s and segmented the long period into four significative parts. The cereal supply model lead to the construction of the supply function related to the Nerlove model. The originality of this approach consisted of analyzing statistically the cereal supply function, not only as a national supply function, but as the aggregation of regional supply function defined from the agro-climatic parameters to the level of the agro-ecological zones. It permits to conduct a regional analysis to get the supposed impacts of the different agricultural policies and to provide new tools for a possible regionalization of the agricultural policies inside the country, and for a better definition of the orientations of cereal production
Luce, Jean-Marie. "Ecologie des Cétoines (Coleoptera : Cetoniidae) microcavernicoles de la Forêt de Fontainebleau : niches écologiques, relations interspécifiques et conditions de conservation des populations." Paris, Muséum national d'histoire naturelle, 1995. http://www.theses.fr/1995MNHN0030.
The Cetoniidae to be found in Fontainebleau are members of the Coleoptera, widespread in Europe, and whose saprophagous larvas live inside cavities of hollow trees. They form a guild which plays a major part in the recycling of ligneous matter in natural forest ecosystems, and they are closely linked to the old states of sylvigenetic cycles. The biology of these species shows noteworthy features suggesting K-type strategies, which is exceptional for coleoptera insects. They undergo a strong decline given the fact they are eliminated by the common forest management. The species Osmoderma eremita (Scopoli, 1763) is part of the priority species of the European directive called " Flora and Fauna Habitats ". They can be used as bioindicators of the biodiversity in saproxylic organisms of forest-type ecosystems, because of their big size and easy identification
Saint-Aubert, Jean-Baptiste de. "Impact of aging on human decision-making in ecological conditions." Electronic Thesis or Diss., Sorbonne université, 2023. http://www.theses.fr/2023SORUS511.
Any given day of a human’s life is made of countless decisions, that are influenced by the way our brain handles perceptive inputs, focuses attentional resources, mobilizes memory, or tries to learn from past choices. These processes change throughout lifespan, and human aging impacts the complex interplay of various cognitive and environmental factors that composes decision-making. Appropriate decisions often rely on a balance between exploring new possibilities and exploiting known options, and several studies have reported that aging shifts decision strategies from exploration to exploitation. However, little is known on how age affects exploration strategies and their neural substrates, let alone in uncertain, real-life environments. The main objectives of this doctoral thesis were: i) to characterize the impact of aging on explorative behavior during probabilistic reward learning; ii) to study the consistency of age-related effects in abstract value-based decision-making and in ecological, spatial decision-making; iii) to understand how neural correlates of decisions processes are shaped in mobile conditions. The methodological approach relied on an in-depth analysis of the best design and modeling choices of the decision tasks used to characterize the exploration-exploitation tradeoff. It also required mobile electroencephalography (EEG) recordings, that we validated by capturing brain correlates subtending cognitive processes during active landmark-based navigation with young adults. With a large-scale desktop-based behavioral study, we first confirmed that older adults rely significantly less on exploration than young adults, although not necessarily to the expense of performance and efficiency, thus using more parsimonious explorative strategies. Second, by using a novel spatial decision task that involved active motion in ecological conditions, we found that older adults can use more random, sub-optimal exploration than young adults in highly uncertain environments where subjects are provided with sparser information about the reward distribution. These findings challenge the classic view of the exploration-exploitation dichotomy based on decision-making paradigms that use abstract representations of options and rewards. Brain activity analysis during the active spatial decision task revealed that older adults presented delayed and less pronounced feedback-related negativity over fronto-central areas than young adults, who showed earlier and stronger visual processing of the negative feedback over visual cortical areas. This confirms previous findings on impaired reward processing during probabilistic learning in older adults, and extends them to active, spatial decision-making scenarios. Overall, these works highlight the need for enriching decision-making paradigms with more ecological setups that engage a broader set of cognitive processes involved in daily-life decision-making. It also stresses the necessity of taking into account the high inter-individual heterogeneity of age-related effects, e.g., by extending our set of behavioral models to more accurately depict exploration strategies in older individuals. Better understanding the multi-facets effects of aging on these mechanisms will be key in a future where it has an increasingly prominent role. Complementing the above main contributions focusing on decision-making throughout healthy aging, an aside project was conducted to assess EEG-based brain responses in blind subjects that received an optogenetic visual restoration therapy. This project was part of the multi-centric phase I/II clinical study PIONEER, which involves a cohort of patients affected by retinitis pigmentosa, a disease that leads to complete blindness over the course of adulthood. The EEG study provided objective evidence of partial visual recovery during a perceptual decision-making task, by demonstrating a modulation of occipital brain activity as a function of visual stimulation
Delattre, Thomas. "Influence de la structure du paysage et des conditions météorologiques sur le comportement de dispersion de Maniola jurtina (Lepidoptera : Nymphalidae, L. ) dans un agroécosystème bocager." Rennes 1, 2010. http://www.theses.fr/2010REN1S217.
Dispersal is the movement of individuals with potential consequences on gene flow. The distribution patterns of metapopulations and communities in the landscapes result from the inter and intra-individual variations of dispersal. The selection pressures due to human-driven landscape changes cause the apparition of specific movement strategies, with a growing contrast between strategies adapted to resource searching inside patches, and patch searching inside landscapes. The quantitative analysis of M. Jurtina dispersal behaviour allowed us to highlight a strategy adapted to long distance dispersal, the “direct moves”, which is different from the “foray loops” strategy that was known for this species, and is adapted to local short-distance exploration. Besides, in ectotherms activity is strongly dependant on meteorological conditions. We showed that this effect applies to dispersal too, that the dispersal strategies of M. Jurtina are differently affected, and that it changes the functional connectivity at the landscape scale. Moreover, we examined the dispersal behaviour of M. Jurtina along a gradient of agricultural intensification, and showed how dispersal is affected by habitat loss and environmental stochasticity. Finally, we estimated the potential corridor role of an agri-environment scheme set up in European landscapes: the grassy field margins. We used a combination of individual-based simulations of movement, and field surveys of movement inside grassy field margins and habitat patches to estimate this corridor function
Stroia, Ciprian. "Étude de fonctionnement de l'écosystème prairial en conditions de nutrition N et P sub limitantes : application au diagnostic de nutrition." Toulouse, INPT, 2007. http://ethesis.inp-toulouse.fr/archive/00000489/.
Taillandier, Vincent. "Contrôle des conditions aux frontières ouvertes d'un modèle de circulation côtière avec une méthode variationnelle d'assimilation de données : application au Golfe du Lion." Phd thesis, Toulon, 2004. http://pastel.archives-ouvertes.fr/pastel-00002365.
Drhimer, Driss. "Etat phytosanitaire des peuplements de chêne-liège de la forêt de la Maamora en fonction des conditions écologiques et de l'anthropisation : études de deux parasites : insectes xylophages, champignons phytopathogènes." Aix-Marseille 3, 2001. http://www.theses.fr/2001AIX30033.
This study constitutes a step to a better understanding of the phytosanitary problems of the cork-oak forest of Maamora. In this study, we have tried to analyze the impact of the abiotic, environmental and stationary factors as wellas the biotic factors related to man activity and parasits activity. The various forest parcelling out dit not succeed : the object of maintaining cork-oak has hot been attained. Increase in population, lire-wood collecting, overgrazing, pollarding, stripping, have contributed to increase thestress, acorn picking limited the regeneration and the motorway and urban developments have greatly breaked up the initial cork-oak forest. The more prevalent and the more common symptoms encountered in this study can be summarized by a transparent crown (71 % of the trees present a crown thinning out), by a fading and a loss of the leaves, by a withering of the shoots which affects more than 50 % of the trees, by a withering of the twigs from the top of the crown due to Diplodia mutila (72 % of the trees show dead boughs, 19 % of which half sapless), by cankers and ozings. The dead boughs let appear a black stroma through the cork cracks. .
Valentin, Sylvie. "Variabilité artificielle des conditions d'habitat et conséquences sur les peuplements aquatiques : effets écologiques des éclusées hydroélectriques en rivière : études de cas (Ance du Nord et Fontaulière) et approches expérimentales." Lyon 1, 1995. http://www.theses.fr/1995LYO10052.
Petucco, Claudio. "Forest health economics : Management of forest pests and pathogens in conditions of global change." Thesis, Paris, Institut agronomique, vétérinaire et forestier de France, 2017. http://www.theses.fr/2017IAVF0007.
In recent decades, the deterioration of forest health resulted in frequent pests’ outbreaks and the diffuse pathogens’ presence. These phenomena threaten forests’ ability to supply ecosystem goods and services to the society. It is therefore necessary to maintain tree health and reduce pest’s and pathogen’s impacts. This thesis approaches three management problems from an economic perspective such as the current invasion and the incumbent invasion of a forest pathogen as well as the outbreaks of a native pest. Starting from these three pest and pathogen management problems, the thesis aims at assessing the impacts of forest pests and pathogens and, secondly, informing how resources can be optimally allocated for assuring the long-term provision of good and services.Pest and pathogens invasions have an impact on the prices of wood products via supply shocks, which, in turn, influence forest management choices, thus introducing feedback effects between market and ecological dynamics at a large scale. The first paper aims at evaluating these impacts by combining a recursive partial equilibrium model with spatial-explicit pathogen-spread and pathogen-induced mortality models calibrated to represent the ash dieback in France (caused by the pathogen Hymenoscyphus fraxineus). Results showed that impacts are not homogeneous across regions and generally depend on the resource distribution, pathogen spread and market structure. We observed that the behavioural adaptation of forest managers (i.e., regeneration and harvesting choices) is a non-negligible component of the total standing volume loss.The second paper focusses on monitoring and control of an incumbent invasion. Monitoring and early detection of invasive species is important to mitigate the damages and reduce the control costs. However, when multiple decision-makers are involved, the monitoring effort of frontier landowners (landowners closer to the introduction point) is suboptimal because it does not consider the negative impacts of the invasion spreading to neighbouring properties. Through a two-player differential game combined with an epidemiological compartmental model, we computed the non-cooperative and the cooperative solution. We designed a monetary payment to sustain cooperation based on an intertemporal decomposition of the Nash bargaining scheme. We showed that this payment assured time-consistent outcomes, meaning that the ex-ante agreement between the two landowners was credible and self-enforcing. The model was calibrated for the possible invasion of the pine wilt nematode (Bursaphelenchus xylophilus) in south-western France.In the last two papers, the analysis is downscaled from the landscape level to the stand level and concentrates on a native defoliator pest. The main objective of the third paper is to adapt forest management to biotic and abiotic disturbances. The classic Faustmann model was combined with a pest population model and a windstorm model to compute the optimal rotation age and the land expectation value (LEV) for different disturbances scenarios. The model was calibrated for maritime pine (Pinus pinaster) plantations in south-western France and Pine Processionary Moth (PPM, Thaumetopoea pityocampa) cyclical outbreaks. Our results showed that storms tend to reduce the optimal harvest age, whereas PPM tends to increase it. Overall, the impact of PPM on the rotation length prevails and, here, risks increase rather than decrease the optimal rotation length. Thinnings increased profitability and constitute an effective hedging strategy against both risks. In the third paper, we introduced a cut-or-keep decision rule to model the forest owner problem after a storm event. Its economic and management implications are further investigated in the fourth paper. Unlike previous economic studies which assumed clearing and replanting regardless of the level of damages, the cut-or-keep condition led to higher payoffs in roughly 75% of the cases
Saboukoulou, Clément. "La ruralité congolaise d'une tradition écologique à une modernité polluante." Reims, 1993. http://www.theses.fr/1993REIML008.
Barselo, Philippe. "Analyse écologique de l'île de Mayotte (archipel des Comores)." Bordeaux 3, 1995. http://www.theses.fr/1995BOR30007.
Ever since the end of the 1970's, owing to an intensive economic development induced by a dramatic population increase, the balance of mayotte ecosystem has been threatened (road constructions, electrification, growing urbanization. . . ). Following a presentation of the physical features, then of the human environment, the study presents an assessment which reveals that today the physical field is severely disturbed by the human activities and that the balance of the marine field is being upset. Finally, the work will list the actions currently undertaken to protect the mahori environment and it will suggest a further development schema concerning the overall protection of the island
Palmioli, Andrea. "China : capillarity and territory : paradigms of diffuse urbanization." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1080/document.
The territorial scale and the form of the territory are fundamental basis to understand metropolitan processes and the changes occurred in its spatial, economic and social structure. The centrality of landforms and of their dynamics inspires more situated approaches, in which the agency of natural elements is integrated. This research investigates the existence of new forms of emerging rurality in the metropolitan basin of the Yangtze Delta. In opposition to the growing gap between infrastructural heritage and society, the priority of the territory is reaffirmed as a theoretical tool and environmental paradigm. The research hypothesis is that the spread of small and medium-sized enterprises in rural areas represents a form of capitalization of the spatial reorganization occurred in the Commune's period. The preliminary factor which originated the process of rural industrialization is based on the restructuring of two strategic territorial resources: the soil structure and the water network. These transformations have led to the formation of numerous hybrid spaces and clusters of small and micro enterprises dispersed over the countryside. As a result, this mode of production has, in turn, reshaped the relationship between the local economy, communities and natural environment giving rise to forms of urban development without fractures, where the relationship between the built space and the agricultural area is no longer of an opposite nature. What emerges is a network of "milieu” where the resulting socio-spatial organization shows a pattern of capillary urbanization in these conventionally defined "non-urban" areas. The notion of urban is changing and ecological rationality can offer fundamental opportunities to analyse, intersect and integrate the various territorial layers
D'Ambrosio-Boudet, Flore. "De l’espèce humaine : affronter l’urgence écologique avec Robert Antelme et Hans Jonas." Thesis, Paris 10, 2018. http://www.theses.fr/2018PA100040/document.
The starting point of my study is the observation that the current ecological emergency (global warming, biodiversity crisis, pollution) shapes our long-term historical condition. The ecological emergency, which results from identifiable economic and social activities, threatens the continued sustainability of a wide range of species and places the future of our species in jeopardy. My dissertation in philosophy consequently explores the concept of human species, which I address from the point of view of its evolving and ecological naturality. In so doing, I intend to take note of the end of a pre-Darwinian definition, and at the same time I refuse to pave the way for any racialist biologism and for the criminal hierarchies it brought about. What is at stake here for theoretical research is the elaboration of an ontology of human species, which will not give in to any deceptive naturalizing doctrine and will provide us with landmarks to face the ecological emergency. This ontology builds upon two authors, Hans Jonas and Robert Antelme, who endured the experience of Nazism. Their works are central to elaborate a non-reductionist dialectical monism, which can generate an ethics of our life in the world and an ethics of greater recognition and extended solidarity. I argue that the ecological emergency is political in so far as it is the future of collective destinies which is at stake. My approach dismisses the urge to save the human species – or parts of it - by resorting to biotechnological enhancements which would supposedly help our species to step beyond the catastrophe or even beyond “humanity” while shirking our responsibility here and now. I accordingly claim that deeper consideration of planetary boundaries - as well as the spectre of death and the desire for power they imply - calls for a work on the conditions in which humans and non-humans can properly inhabit the world and the democratic experience can be renewed without giving way to panic
Lapeyrie, Frédéric. "Les mycorhizes de l'eucalyptus en conditions d'excès de carbonate de calcium : approche écologique et physiologique des associés ectomycorhiziens." Lyon 1, 1987. http://www.theses.fr/1987LYO10056.
Rajoson, Landy. "L' analyse écologique des conditions et des contraintes dans l'étude des phénomènes de transposition didactique : trois études de cas." Aix-Marseille 2, 1988. http://www.theses.fr/1988AIX22013.
Isabel, Laurie. "Indicateurs pour l'évaluation de la condition des communautés épibenthiques de l'estuaire et du golfe du Saint-Laurent." Master's thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/66976.
Vieira, Pak Manuela. "Le boom de la quinoa dans l’Altiplano Sud de la Bolivie : bouleversement du système agraire, discours et tensions socio-environnementales." Thesis, Paris, AgroParisTech, 2012. http://www.theses.fr/2012AGPT0090/document.
The globalization of quinoa (Chenopodium quinoa) production began in the 1980s in the Southern Highlands of Bolivia. It has generated transformations in the agrarian system of the region questioning the production sustainability. The low quinoa yields experienced by quinoa producers within indigenous communities is a major issue for the different actors of the production chain, scientists, development institutions and policy makers. Today, they mainly attribute it to soil degradation. Consensus that changes in current field-level practices are needed has led to a search for agro-technical innovations. This study analyses the transition from subsistence agriculture to an export-oriented production system, underlying factors that could explain low yields and territorial resource management issues. We use various theoretical frameworks (farming systems, political ecology and collective action) to characterize the changes that occurred at different temporal and spatial scales, from actual producers’ individual life courses to the history of this region for the last forty years. Interviews, participatory observation, workshops and role-playing games were conducted in four rural communities. Results show that explaining low yields by soil degradation has no sound scientific basis. Moreover, this explanation does not take into account the complex interactions that exist between environmental, technical, social and political factors. In fact, this study first shows that actual farming practices are not adapted to the agro-ecological conditions of the new production areas, and that the organic certification norms are not sufficient to ensure the production sustainability. It also stresses the emergence of social tensions related to the new rules of land access and land use, which emerge in a context of weakening of the community’s authorities, of high spatial mobility and of the diversification of activities among the farmers. It finally reveals a disconnection between research and development activities and this new context. Soil degradation is an agro-technical discourse disseminated among market chain actors which hides crucial problems. Rebuilding a sustainable relationship between communities and their environment require collective agreements for land and agricultural resource management, and a broader vision that takes into account social, institutional and political processes
La globalización de la producción de quinua (Chenopodium quinoa) iniciada a partir de los años 80 en el Altiplano Sur de Bolivia, se constituyó en un vector de cambios que generó profundas transformaciones en el sistema agrario de esta región. Estas transformaciones hicieron emerger, entre los actores involucrados en la cadena productiva y quienes se relacionan con ella (científicos, instituciones de desarrollo, tomadores de decisiones), una generalizada preocupación sobre la sostenibilidad de la producción. Dichas inquietudes, centradas principalmente sobre los bajos rendimientos obtenidos por los agricultores, se le han atribuido a la degradación de los suelos, alertando sobre la urgente necesidad de que se modifiquen las prácticas agrícolas mediante diversas innovaciones agrotécnicas. Frente a esta problemática, este estudio analizó las transformaciones agrarias surgidas de la transición de una agricultura de subsistencia a una agricultura de exportación así como los factores de fondo que explican los bajos rendimientos obtenidos por los agricultores. El estudio se apoya sobre diferentes enfoques teóricos (sistemas agrarios, ecología política y teoría de acción colectiva) para analizar las transformaciones descritas a través de diferentes escalas temporal y espacial, desde las trayectorias de vida de algunos agricultores hasta la historia regional de los últimos cuarenta años. Igualmente, se aplicaron diferentes herramientas (entrevistas, observación participante, talleres participativos y juego de roles) en cuatro comunidades representativas y ante actores institucionales en las escalas regional y nacional. Nuestro análisis revela que atribuirle a la degradación de los suelos la baja productividad de los cultivos no posee ningún fundamento científico serio. Esta explicación no toma en consideración las complejas interacciones que se presentan entre los factores ambientales, técnicos, sociales y políticos del sistema. En efecto, este trabajo demuestra en primer lugar, la desadaptación de las prácticas actuales de cultivo a las condiciones agroecológicas de las nuevas zonas de producción así como la insuficiencia de las normas de certificación orgánica para asegurar la sostenibilidad de la producción. En segundo lugar, revela el surgimiento de tensiones sociales vinculadas a las nuevas reglas de acceso y uso de la tierra, en un contexto en el que se presenta un debilitamiento de la gestión comunal en la gestión de los recursos y en el que la movilidad espacial y la pluriactividad caracterizan a la población cultivadora de quinua. Finalmente, demuestra la falta de articulación entre las acciones de investigación y desarrollo y el contexto actual. La degradación de los suelos es un discurso agrotécnico difundido por algunos actores de la cadena productiva. Este discurso oculta los problemas vinculados a la gestión individual y colectiva de los recursos territoriales, profundamente transformados por el auge de la quinua. La construcción de acuerdos colectivos para reconstruir una relación sostenible entre las comunidades y su ambiente debe abordarse desde una visión territorial que toma en cuenta los procesos sociales, institucionales y políticos
Arvanitakis, Laurence. "Interaction entre la teigne du chou Plutella xylostella (L.) et ses principaux parasitoïdes en conditions tropicales : approche éthologique, écologique et évolutive." Phd thesis, Université Paul Valéry - Montpellier III, 2013. http://tel.archives-ouvertes.fr/tel-00984578.
Charrier, Christophe. "Effets de la modification anthropique (rejets, aménagements) de la variabilité des conditions physico-chimiques des cours d'eau sur leur fonctionnement écologique." Lyon 1, 1997. http://www.theses.fr/1997LYO10138.
Geslin, Thomas. "Territorialité en périodes de reproduction et d'hivernage chez la gorgebleue à miroir (Luscinia svecica) : aspect écologique, démographique et physiologique." Rennes 1, 2002. http://www.theses.fr/2002REN10087.
Marzin, Anahita. "Indicateurs biologiques de la qualité écologique des cours d’eau : variabilités et incertitudes associées." Thesis, Paris, AgroParisTech, 2013. http://www.theses.fr/2013AGPT0002/document.
Sensitive biological measures of ecosystem quality are needed to assess, maintain or restore the ecological conditions of rivers. Since our understanding of these complex systems is imperfect, river management requires recognizing variability and uncertainty of bio-assessment for decision-making. Based on the analysis of national data sets (~ 1654 sites), the main goals of this work were (1) to test some of the assumptions that shape bio-indicators and (2) address the temporal variability and the uncertainty associated to prediction of reference conditions.(1) This thesis highlights (i) the predominant role of physiographic factors in shaping biological communities in comparison to human pressures (defined at catchment, riparian corridor and reach scales), (ii) the differences in the responses of biological indicators to the different types of human pressures (water quality, hydrological, morphological degradations) and (iii) more generally, the greatest biological impacts of water quality alterations and impoundments. (2) A Bayesian method was developed to estimate the uncertainty associated with reference condition predictions of a fish-based bio-indicator (IPR+). IPR+ predictive uncertainty was site-dependent but showed no clear trend related to the environmental gradient. By comparison, IPR+ temporal variability was lower and sensitive to an increase of human pressure intensity. This work confirmed the advantages of multi-metric indexes based on functional metrics in comparison to compositional metrics. The different sensitivities of macrophytes, fish, diatoms and macroinvertebrates to human pressures emphasize their complementarity in assessing river ecosystems. Nevertheless, future research is needed to better understand the effects of interactions between pressures and between pressures and the environment
Robert, Marianne. "Le comportement des thons tropicaux autour des objets flottants : de l’étude des comportements individuels et collectifs à l’étude du piège écologique." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20118/document.
Research in fisheries science aims at investigating the functioning of fish population with the objective of using this knowledge to propose sustainable management measures. This PhD thesis relies on a collection of experiments and modelling designed to further our knowledge on the aggregative behaviour of large pelagic fish with floating structures at the surface of the ocean. The overall objective is to test whether the thousands of man-made floating structures deployed by fishermen (also referred as Fish Aggregating Device –FAD) act as ecological traps for tropical tunas. To archive this main objective, it was first necessary to characterize the individual behaviour of tuna in a network of FAD. In the first chapter, the analysis of 96 acoustically tagged yellowfin tuna (Thunnus albacares) between 30-96 cm FL in the array of anchored FADs around Oahu (Hawaii, US) shows that individuals tuna exhibited behavioural plasticity while in the array and that behaviour around FAD is size dependent. In order to assess the impact of the increasing density of FAD, the major habitat modification, it is essential to understand the factors that influence the residence time at FADs. In the second chapter, binary choice experiments suggest that the aggregated biomass under the FAD play a role in the aggregative process. Nonetheless, quantification of arrival and departure dynamics of fish to FAD are required to validate the assumptions we proposed on the underlying social mechanism. Such model would, then, allow testing the effect of FAD density and environmental conditions on individual residence time and spatial distribution of population. In the third chapter, the comparison of skipjack tuna (Katsuwonus pelamis) condition between individual associated with logs and in free swimming schools in the Mozambique Channel, an area known to be naturally enriched with logs with few FADs, highlights the need for estimating reference points prior to assessing the impacts of anthropogenic modifications to habitats on animals.Combining the different chapters, our results tend to favour a social rather than a trophic role of floating objects in the ecology of tunas. More generally, we discuss what novel insight our results bring up on the ecological trap hypothesis. Tropical tunas represent an interesting model species on which we focused. However, the theoretical framework of the questions we addressed, the observation and analytical tools we developed are generic enough to be applied to the others species that are encountered around floating structures. In a broader extent, this work meets the general topic of studying behavioural strategies and distribution of population in multi-patch environment
Sanhueza, Daniel. "Effets des conditions environnementales sur la croissance et l'expression génique de Mycobacterium ulcerans, agent causatif de l'ulcère de Buruli." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTT054.
Mycobacterium ulcerans (MU), the causative agent of Buruli ulcer (BU), an emerging human infectious disease, is associated with tropical aquatic environments, particularly those modified by human activities. The ecology of this mycobacterium is still poorly understood, and questions remain about its transmission cycle within ecosystems and from nature to humans. Nowadays the research orientation is to show the existence of a multitude of host taxa carrying the bacillus in both aquatic and riparian ecosystems. Thus, it is likely to think that one or a few common factors might contribute and explain the presence and development of this bacillus across distinct localities and regions.In this context, we have developed experimental approaches in the laboratory to analyze the effects of several environmental parameters, selected as being important in the definition of the MU ecological niche and in its growth and persistence in natural ecosystems. Considering ranges of values encountered in endemic and non-endemic regions where BU occurs, we first tested the effect on MU growth of two polysaccharides widely present in nature (chitin and starch) and five chemical components (iron, calcium, zinc, phosphate and sulfate) representing essential nutrients for bacteria. Our work shows that chitin increases significantly the growth of MU. Conversely, the presence of starch does not favor its development with time. Calcium is the only chemical element contributing to increase MU cell number over time, but this effect remains very marginal. The lack of effect exerted by iron, zinc, sulfate and phosphate on the in vitro growth of MU suggests that values used in our experiments correspond to the limit values to explain the geographical distribution of MU in tropical aquatic ecosystems.Secondly, given the few existing information about the role of pH on the presence and development of MU in natural settings, we have reproduced in the lab some environments to study the growth of MU depending on different pH values encountered in regions of Cameroon and French Guiana where the mycobacterium can be present or absent. Our results show that pH has a significant effect on MU growth with a greater effect at pH values close to 6.0. In addition, there is a strong interaction between pH and chitin as to the same pH bacterial growth is 10 times greater in the presence of medium with chitin. These results also suggest that pH too acidic, lower than 5.0 are unfavorable for MU growth.Finally, we looked at gene expression of different MU cultures from different experimental frameworks. Here, and by making use of a new RNA sequencing approach, we studied the genetic expression of MU in differents environments. We are especially interested in the expression of genes implicated in the metabolic pathways of mycolactone production, the peptide toxin responsible of ulcerations in human. Specific environmental contexts could lead to an over-expression of these genes by MU populations, thus pinpointing the fact that MU ecology and epidemiology could be (micro-) context-dependent having some pathological and clinical implications. Taken together, our results participate in a research allowing to better understand the key parameters of the ecological niche of MU, and beyond helping to identify the aquatic ecosystems favorable or not to the maintenance and development of this mycobacterium responsible for Buruli ulcer
Marzin, Anahita. "Indicateurs biologiques de la qualité écologique des cours d'eau : variabilités et incertitudes associées." Phd thesis, AgroParisTech, 2013. http://pastel.archives-ouvertes.fr/pastel-00879788.
Joud, Didier. "Complexe morphogénétique, historique et écologique des écosystèmes forestiers "hydromorphes" des plateaux et terrasses du Bas-Dauphiné." Université Joseph Fourier (Grenoble ; 1971-2015), 1997. http://www.theses.fr/1997GRE10069.
Beau, Cécile. "Représentations de la nature en Espagne : de l’exode rural à l'émergence d’un discours écologique (1950-2020)." Electronic Thesis or Diss., Paris 3, 2022. http://www.theses.fr/2022PA030031.
Spanish society, essentially agricultural until the 1950s, underwent an accelerated industrialization, promoted by Franco's government, which led to a rapid and irreversible decline of rural areas. These territories became depopulated spaces that the state allowed to decline in favor of the central core (Madrid), some peripheral regions (such as the Basque Country and Catalonia) and new coastal tourist centers. Through the analysis of the discourse on nature and the agrarian world from 1950 to the present time, this research work focuses on the role of the rural exodus in the socio-economic evolution of Spain and attempts to shed light on the way ecology has spread in this country as deruralization has progressed. The consequences of the disappearance of the peasant societies that once occupied the spaces that today are known as España vacía (empty Spain) have been relatively little studied. However, several writers of the second half of the twentieth century have studied the history of this "silent revolution": Miguel Delibes, Julio Llamazares Rafael Chirbes, among others, lament in their novels the fate of these regions and their inhabitants and highlight the contradictory relationship that Spaniards have with their rural past. Also, the former agricultural territories, neglected and marginalized by the public authorities, seem to be regaining the importance they once had in the eyes of the Spaniards. For rural Spain becomes a political issue from the moment we look at it, both in the past, questioning how to overcome the wounds caused by the civil war and the dictatorship, of which it still bears the scars, and in the future, through the question of how to respond to the environmental crisis, preserving nature and farmland
Choukou, Mohamed Amine. "Effet de la croissance, du genre et de l'expertise sur les propriétés biomécaniques des membres inférieurs." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00771368.
Robert, Marianne. "Le comportement des thons tropicaux autour des objets flottants: de l'étude des comportements individuels et collectifs à l'étude du piège écologique." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209681.
Pour mener à bien ce travail, nous avons dans le premier chapitre caractérisé le comportement individuel de thons dans un réseau de DCP ancrés. L’analyse de données de marquage acoustique de 96 thons albacores (Thunnus albacares) (30-96 cm) à Hawaii montre que les thons présentent une plasticité comportementale forte face aux DCP qu’ils rencontrent mais également que le temps de résidence sous les DCP diminue avec la taille des individus. Afin de quantifier l’impact de l’augmentation de la densité de DCP il est essentiel de comprendre les mécanismes et les facteurs qui influencent les temps de résidences sous les DCP. Dans le second chapitre, des expériences de choix binaires suggèrent un rôle de la biomasse agrégée dans la formation, la maintenance et la dispersion des agrégations que forment les thons sous les objets flottants. La quantification de la dynamique des arrivées et des départs des poissons aux DCP permettra de valider les hypothèses que nous proposons concernant les mécanismes sociaux sous-jacents d’une part et d’autre part de tester l’influence de la qualité de l’environnement et de la densité de DCP sur les temps de résidences individuels et la distribution spatiale des populations. Dans le troisième chapitre, la comparaison de facteurs de condition de listaos (Katsuwonus pelamis) matures capturés en bancs libres et sous objets flottants dans une zone naturellement riche en objets flottants, et relativement peu impactée par le déploiement de DCP (Le Canal du Mozambique), nous a permis d’établir un point de référence essentiel pour estimer les effets des perturbations actuelles. Plus généralement, les résultats obtenus dans les différents chapitres tendent à conforter l’hypothèse d’un rôle social et non trophique des objets flottants dans l’écologie de thonidés. Les résultats obtenus durant cette thèse amènent à poser un regard nouveau sur l’hypothèse du piège écologique.
Notre travail s’est principalement intéressé à un modèle biologique de choix, les thons tropicaux. Cependant le cadre théorique des questions abordées, les outils d’observations et les méthodes d’analyses développées sont assez génériques pour être appliqués aux autres espèces rencontrées sous les objets flottants. Cette recherche s’intègre plus généralement dans les problématiques visant à mieux comprendre les stratégies comportementales et la distribution des populations dans des environnements multi-sites.
Doctorat en Sciences agronomiques et ingénierie biologique
info:eu-repo/semantics/nonPublished
Bénézet, Paul. ""It's our home" : expressions de la relation au territoire des Dane-zaa de Doig River (Colombie-Britannique, Canada)." Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/30279/30279.pdf.
Focused on the concept of land, this master’s degree thesis is a presentation of what this notion represents for a group of hunter-gatherers of western Canada. Settled for thousands of years on the foothills of the Rocky Mountains in North-East British-Columbia and in Alberta, the Dane-zaa (“The Real People”), intimately engaged in their environment, have been developing knowledge and technics adapted to a rational and sustainable land management, generation after generation. However, this relationship does not only concern the exploitation of the resources the land provides, but also the bonds between humans and non-humans who share it. Since the arrival of the first euro-Canadians settlers and the signature of Treaty 8 in 1900 which ordered the creation of a reserve, the land of the Dane-zaa, their “home” and a space of history and memory, has been fragmented and has become the site of political and economic stakes and interests often divergent and which can hardly been reconciled.
Alvergne, Alexandra. "L’investissement paternel chez l’Homme : une approche évolutive." Montpellier 2, 2008. http://www.theses.fr/2008MON20178.
Human paternal investment is highly variable between populations, but also between individuals. This variability is partly explained by socio-ecological factors, such as paternity uncertainty or the reproductive system. Due to kin selection, the level of paternal investment is expected to be lower when paternity uncertainty is higher. Our research has shown that fathers use paternity cues to adjust their investment in paternal care. Using a cross-cultural approach, the link between phenotypic resemblance to the father (as perceived by the father, the mother or external judges) and the level of paternal investment has been quantified. The results indicate that paternity uncertainty has constituted a selective pressure favoring the use of paternity cues by men, as well as a manipulation by women of men's perception. Moreover, several phenotypic traits are possibly used for paternity assessment (i. E. Faces, odors). Besides, the link between the degree of paternal investment and the child's physical condition has been assessed, and the results suggest that the expression of a strong resemblance to the father is, through the gain of paternal investment, associated with fitness benefits for children. Finally, the evolution of a paternity cue in response to discriminative paternal investment has been modeled, including the proposed mechanism of genomic imprinting, and confronted to empirical data. Additionally, we showed that the expression of paternal investment depends on hormonal factors, and that the regulation of paternal investment through testosterone is a trait which is shared by different populations. All these results are discussed within the theoretical frameworks on the evolution of familial and social behaviors
De, almeida Tania. "Impact d’une espèce ingénieure de l’écosystème et son utilisation en restauration écologique : Le cas de Messor barbarus (L.) dans les pelouses méditerranéennes Above- and below-ground effects of an ecosystem engineer ant in Mediterranean dry grasslands Harvester ants as ecological engineers for Mediterranean grassland restoration: impacts on soil and vegetation A trait-based approach to promote ants in restoration ecology." Thesis, Avignon, 2020. http://www.theses.fr/2020AVIG0358.
The main objective of this thesis was double: (i) to assess the impact of an ant species on its ecosystem, in order to (ii) deduce potential applications in the field of ecological restoration.Ants are among the most abundant organisms in terrestrial ecosystems and occupy a wide range of geographical areas. They play key ecological roles in many ecosystems as soil engineers, predators or regulators of plant growth and reproduction. However, the information collected locally is often fragmented and does not provide a complete overview of the impact of a species on its environment.Messor barbarus (L.), known to redistribute seeds and to modify the soil physico-chemical properties, is widespread in South-Western Europe, particularly in Mediterranean grasslands. Therefore, it may play a major role in the composition and structuring of these ecosystems, which are characterised by high biodiversity but whose abundance and surface area have decreased drastically in recent decades.Through a multi-compartment study, we confirmed the hypothesis that M. barbarus is an ecological engineer in Mediterranean grasslands. This species changes this habitat by modifying, as expected, soil physico-chemical properties. These modifications are associated with an increase in both biomass and heterogeneity of plant communities, as well as changes in above- and belowground fauna (abundance, occurrence and structure of communities). Messor barbarus profoundly changes trophic and non-trophic relationships within and between species and their habitat. The heterogeneity created locally by the activity of M. barbarus leads to a diversification of ecological niches within these grasslands.Despite their major role in the functioning of ecosystems, ants are rarely considered in restoration ecology. In our study site, corresponding to a dry grassland rehabilited after an oil leak and a soil transfer, M. barbarus contributed to accelerate the restoration of the soil physico-chemical properties but also of the seed bank in the medium term - seven years after the rehabilitation. These results make this species a good candidate for ecological engineering.In order to generalise the use of ants in restoration ecology, we propose a trait-based methodology for stakeholders. We evaluated the potential of ants in restoration ecology, then listed all the traits known to affect abiotic and biotic compartments and/or relevant to monitor the success of the restoration phase. The proposed methodology provides a first selection of potentially relevant species according to the restoration objectives
Bruckmann, Laurent. "L'intégration des zones inondables dans la gestion de l'eau et le développement de l'irrigation d'une vallée fluviale sahélienne : le cas des terres de décrue de la moyenne vallée du Sénégal." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC214/document.
Since the decline of water resources in the 1970s, the middle Senegal river valley is a space dealing with many socio-environmental changes. Public policies have controlled the river with two dams, Manantali and Diama, and made the valley the preferred location for the development of irrigated agriculture for the national supply of rice. Faced to this situation, the floodplains wetlands, characterized by a flood/recession rythm, are forgotten by development policies. The objective of the thesis is to understand how these flood recession lands fit into socio-environmental changes, and finally to define their current roles for local populations into the reorganization of the middle Senegal river valley.The work is based on a study of the socio-ecological system of the floodplain of the middle valley. The methodology thus has several components. A hydrological analysis and a mapping of the dynamics of the flooded areas by remote sensing, showed the importance of the management choices of the Manantali dam in the allocation of water for the flood in the valley. Socio-economic surveys, carried out in four village terroirs and using semi-structured interviews, highlighted the integration of flood-recession related activities into household strategies, and define the economic, food supply and ecological functions between the different agro-ecological units of the floodplain. Finally, factors holding flood-recession related activities have been identified at household level, such as the diversity of ecosystem services, the heritage value of these areas and the integration of households in irrigation
Lagoutte, Julien. "Les conditions de la responsabilité en droit privé : éléments pour une théorie générale de la responsabilité juridique." Thesis, Bordeaux 4, 2012. http://www.theses.fr/2012BOR40032.
While the radical distinction between criminal law and civil liability is classically taught, a thorough survey of positive law reveals a general and profound trend towards a confusion of these two disciplines. Faced with this paradox, the jurist wonders : how to articulate the civil and criminal laws of responsibility ? To answer this question, the thesis suggests abandoning the traditional approach of the subject, which consists in treating it as a mere category of classification of the different branches, civil and criminal, of responsibility/liability. Legal responsibility is presented as an autonomous and general institution organizing the response from the system to abnormal disturbance of social equilibrium. Civil liability law and criminal law are, as far as they are concerned, henceforth conceived as the mere technical applications of this institution in positive law.On the basis of this new approach and through the prism of the study of liability conditions in private law, the thesis proposes a technical and rational organization of criminal law and civil liability that may provide the guiding principles of a real general theory of legal responsibility. As a general institution, it gives not only a concept of responsibility, requiring degradation of a legally protected interest, abnormality and legal causation, and establishing the convergence of criminal law and civil law, but also a system of responsibility, determining the divergences of them and steering the first towards the protection of general interest and the second towards the protection of victims
Shumskykh, Mykyta. "Release of trace elements from contaminated sediments into surface waters during sediments dynamics : an experimental study." Thesis, Tours, 2019. http://www.theses.fr/2019TOUR4008.
In aquatic systems, most of trace metals (TM) are buried in sediments and then can be released according to chemical conditions and microbial activity occurring at the sediment-water interface. The aim of this study was to assess the impact of resuspension events (flood or maintenance operations for dam reservoir) on the mobility of some TM. Different batch experiment conditions were chosen to mimic those events: under oxic and anoxic conditions on raw sediments and on gamma-irradiated ones (“sterilized” one). The use of deionized water allowed maximizing the release process. Two sediment types issued from different contexts were selected: the Villerest dam reservoir (France) and the Xiang River (China). Long term experiments (30-day long) allowed identifying that organic matter degradation, microbial activity and alteration/dissolution of trace metal bearing phases were the main controlling factors. The gamma-irradiation did not sterilize sediments but only limited aerobic bacteria and enhanced anaerobic activity. The impact of such 24h resuspension event on reservoir waters and downstream biota is very limited as less than 1% of trace elements was released
Shimi, Anouar. "Enjeux sociaux, économiques et politiques d'utilisation des ressources en eau dans le Nord-Ouest tunisien." Thesis, Paris 1, 2014. http://www.theses.fr/2014PA010681/document.
Kef is a region of Tunisia not so studied among researchers. Water availability, studied from the qualitative and quantitative point of view requires crossing obvious variables such as hydrogeology, climatology, but also socio-economic or cultural variables. This research took into account the importance of the working scale, replacing Kef context in Tunisia national context before focusing on the specifics of this governorate. It shows the importance of water resources in the socio-economic development of Tunisia and Kef in particular. Water resources in Kef are important and of good qualities: well used, they should speed up the development of agriculture and industry. Moreover, the interesting potential of thermal and mineral water provides another economical alternative which could allow development of environmental friendly mountain and thermal tourism
Houngnandan, Fabrice. "Rôle des pressions anthropiques et de l’environnement dans l’état des herbiers de posidonies de Méditerranée française." Thesis, Montpellier, 2020. http://www.theses.fr/2020MONTG029.
Human activities are the main cause of global changes with adverse impacts on all biodiversity, both terrestrial and marine. In this context, many countries, including France, wish to stop this problem by improving networks for monitoring and managing ecosystems using new methods and approaches that aim, in particular, to achieve good ecological status of their water masses. This is the main objective of this thesis project, focusing on a Mediterranean sentinel ecosystem, the Posidonia oceanica seagrass. P. oceanica is an underwater plant endemic to the Mediterranean, and an indicator of the quality of its environment. By linking its spatial distribution with biological data and anthropogenic pressures, it is possible to develop new indicators that are easy to measure at the scale of the entire French coastline (1800 km).Through a multidisciplinary approach, combining participatory mapping, analysis of old images and current ecological data, we have been able to identify the location of former P. oceanica seagrass that have now disappeared and quantify the extent of the decline (70% in 66 years for example in Agde and Rochelongue). Our results also show that the indices of landscape composition and configuration reflect well the state of conservation of a P. oceanica seagrass. Using these landscape indices, we have developed a new approach to define key conservation areas for the management of P. oceanica based on the influence of environmental variables and human activities. Finally, we have also shown that by degrading the P. oceanica seagrass, human activities favour the installation of invasive exotic algae, but can also act as a barrier to invasions by modifying local environmental conditions and making them unfavourable to invasive species.These results suggest multiple applications to improve the management and monitoring of the marine environment in the French Mediterranean
Blásquez, Martinez Lidia Ivonne. "La reformulation identitaire et le développement durable : les xochimilcas à Mexico : les enjeux des usages sociaux et politiques d'un espace naturel." Paris, EHESS, 2007. http://www.theses.fr/2007EHES0027.
This research intends to explore how the new discourse and policies on environmental conservation and natural heritage are interacting with and influencing the local dynamics and perceptions of space and territories. It is based on the case of the Xochimilco Lake, located at the heart of Mexico City, which used to be the city's main provider of water and vegetables and has been recognized by UNESCO as a World Heritage. The study analyses how the recognition of the Lake as a natural reserve have modified the practices of the landowners and their representation of the Lake. It also ' looks at processes of social change within the local political arena whereby political action have been transferred from the agrarian sphere to the ecosystem management sphere. Thorough the study of the life trajectories of local actors, the author eventually explores how the recognition of the lake as a World Heritage has foster or re-shape local conflicts over land and natural resources at different scales, local, national and international
Leblanc, Marie-Eve. "Les conditions liées à l’intégration de l’approche écologique dans la programmation de prévention-promotion offerte à la clientèle aînée par des CSSS du Québec : une étude de cas." Thèse, 2010. http://hdl.handle.net/1866/3866.
This multiple case study investigates conditions that influence the integration of an ecological approach in disease prevention and health promotion (DPHP) programs offered to older adults by local health organizations in Quebec. Scheirer’s implementation model guided the study in five CSSS that were selected to portray differing degrees of ecological character in their DPHP programs. Data collection proceeded through content analysis of thirty-eight semi-structured interviews conducted with professionals and managers as well as document analysis. Professional, organizational and environmental factors were explored. Results indicate that the ecological character of programs is influenced by organizational norms, competing priorities, team structure, external partnerships, preconceived ideas regarding DPHP for older adults as well as professional interest and training. These results suggest avenues for action to optimize the impact of services offered to an ageing population through disease prevention and health promotion programs.