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Stable carbon (δ13C) and nitrogen (δ15N) isotope ratios are commonly used to reconstruct palaeodiets and palaeoenvironments. The method is based on our knowledge of isotopic patterns in plants, which are subject to taxonomic and environmental variability. While previous researchers have addressed isotopic variability amongst plants, no studies have looked extensively at a broad suite of taxa over multiple temporal scales from within the savanna biome so as to provide baseline data for palaeodietary and palaeoenvironmental studies. Here we document variations in the isotopic compositions of plants collected over two years from the Kruger National Park, South Africa, with respect to species and anatomical differences, and the influences of geological substrate and spatio-temporal shifts in climate. Results show that environmentally-induced carbon isotopic variations in plants within this region are generally smaller than 2‰, which is lower than what has been previously reported for plants compared across multiple habitat-types. These data suggest that δ13C differences of 2‰ or more (or 1‰ if the diet is predominantly C4) between animals from a given area reliably indicate real dietary differences. Plant δ15N values vary greatly between different microhabitats (by up to 4‰), responding to a range of environmental influences that may, in turn, significantly influence variation in animal δ15N values.  相似文献   
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L'information devient de plus en plus un enjeu crucial pour les institutions et acteurs engagés dans des processus territoriaux de développement. Comme la littérature sur les NTIC le démontre, l'accès a l'information concernant leur environnement global (sources de capitaux, tendances globales, débouchés, encadrement) ainsi qu'à celle concernant leurs atouts locaux et spécifiques (ressources humaines, physiques, financièrs et institutionnelles, identités, possibilités de mobilisation) fournit des indications indispensables pour faction des collectives locales engagées dans des projets de développement. Cependant, ce qui est souvent négligé c'est que le processus même par lequel cette information est produite et diffusée constitue en soi un facteur intervenant dans l'orientation que prend le développement. L'information marque les territoires concernés. Aussi est-il essentiel de construire des inforoutes permettant la participation des collectivités à la production de l'information qui les concerne. L'Atlas du Québec et de ses régions est une expérience qui vise cet objectif. Dans ce texte, nous présentons l'état d'avancement et les conclusions préliminaires de cette expérience. Information networking is a crucial issue for organizations and socio-economic actors. As the literature on development shows, information at the global level (financial perspectives, global tendencies, markets, and regulations), as well as at the local level (demographic and social characteristics; human, physical, economic, institutional, and organizational resources; specific assets; quality of life; etc.) is indispensable to local collectivities involved in development projects. Nevertheless, often overlooked is the fact that the very process by which this information is produced and disseminated has a significant effect on the direction of development. Information has an impact on the local community. There is a need for building territory information networks that allow local communities to produce the information that concerns them. This paper presents first a global survey of globalization and the effects of information highways on specific territories, and second, an experiment in progress about building a territory information network in the province of Québec, the Atlas of Québec and Its Regions.  相似文献   
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In this paper, I explore how working-class young people in Leicester hope and plan for their futures as they consider the possibility of attending university. I respond to Pimlott-Wilson’s [2011. “The Role of Familial Habitus in Shaping Children’s Views of Their Future Employment.” Children’s Geographies 9 (1): 111–118] call for further research to investigate how individual dispositions and habitus affect how young people hope and aspire towards the future. I do this in three ways. First, I empirically test Webb’s [2007. “Modes of Hoping.” History of the Human Sciences 20 (3): 65–83] hope theory to understand how aspirations are formed on an individual and societal level. In doing so, I critically question what is understood by the term ‘aspiration’. This allows me to question what it means for young people to ‘raise aspirations’ towards university. Second, I explore how a spatial analysis can contribute towards an understanding of how habitus, hope and aspirations interlock to shape young people’s futures. Third, I argue that hope can be regarded as a form of capital which in turn influences habitus.  相似文献   
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