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71.
This address is concerned with the lack of detailed understanding we have of rivers. It is argued that to manage river systems for environ- mental and ecological sustainability, there must be understanding of riverine biophysical processes. These are explored through a consideration of: (1) channel airspace and water; (2) the perimeter conditions of the channel as the boundary between erosional channel and depositional floodplain, both of which occupy the valley-floor trough; (3) ecological components of channels and (4) the human components where human interactions with catchment environments have such impacts on the biophysical systems. Finally, the implications of these four components for understanding the systems for more sustainable management are discussed.  相似文献   
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Ancient mortars from northern Italy, dating from the fifth to the seventeenth century AD, were examined in order to formulate an hypothesis regarding the origin of the white lumps often observed in these mortars and in other samples of the same geographical provenance. Various characterization techniques were employed, including scanning electron microscopy, X-ray powder diffraction and Fourier transform infrared (FTIR) and micro-FTIR spectroscopy.  相似文献   
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Relatively little is known about the possibilities and limitations of voluntary public programs. The so-called 33/50 Program for reducing releases of certain toxic chemicals into the environment provides a useful instance for examination. In an investigation of toxics-reduction outcomes, with states as units of analysis, economic and policy variables help to explain the results. In particular, channels and approaches used In communicating policy intentions are related to outcomes. Voluntary programs can make a difference, but the details of execution, including the extent and nature of field efforts, influence outcomes.  相似文献   
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The special number of the Canadian Geographer devoted to West Edmonton Mall raises important questions, notably that of the relative status, as values, of work (seen historically as fundamental to our culture), and of leisure, perceived, albeit controversially, as being embodied in wem. In preparing to present my principal thesis, I review recent reinterpretations of human behaviour advanced by workers in the fields of symbolic interaction and the sociology of knowledge. These schools ha ve given rise to the concept of, though not the term, functional religion. The meaning of this concept is close to that of ideology; a comparative analysis of the two terms justifies using the former. A survey of recent work by geographers who approach religion from a functional point of view closes the second part of the paper. In the course of this review the relative status of work and leisure emerges as a significant issue. The view of leisure as a norm presented in the third part of the paper is that advocated by Pieper, Huizinga, and de Grazia. They argue that the Classical view, according to which human life finds its meaning in activities that are carried on for their own sake (e.g., games), rather than in those pursued for the material rewards they offer, is correct. Following their lead, and in opposition to both Marxists and Liberals, I argue that the adoption of leisure as a fundamental value would provide a more satisfactory foundation for our culture than work has to this point. Le numéro spécial du Géographe canadien consacréà?étude du West Edmonton Mall soulève plusieurs questions importantes, notamment celle du statut relatif, comme valeur, du travail (valeur-clé historiquement dans notre culture) et du loisir, valeurs incarnées, bien que de façon controversées, dans le WEM. Pour établir les bases de la thèse principale, on examine les réinterprétations récentes du comportement hurnain avancées, dans les sciences humaines, par des chercheurs travaillant dans les domaines de ?interaction symbolique et la sociologie du savoir. Ces écoles ont engendré le concept, sinon le terme, de la religion fonctionelle. Le sens de ce terme est proche de celui de ?idéologie; une analyse comparative des deux termes justifie ?emploi du premier. Pour conclure la deuxièrne partie de ce mémoire, on passe en revue quelques écrits récents par des géographes qui abordent la religion ?un point de vue fonctionnel. De cet examen il ressort que le statut relative du travail et du loisir est ?une importance capitale. Dans la troisième partie, on présente une perspective sur le loisir qui est proche de celle qu'avancent Pieper, Huizinga, et de Grazia. Ceux-cisupportent la position des auteurs classiques, selon qui la vie humaine trouve sa signification dans les activités entreprises pour ellesměmes (par exemple, les jeux) plutǒt que pour le gain matériel. Appuyant leur argument, et m'opposant à celui des marxistes et des libéraux, je prétends que ?adoption du loisir comme vaieur fondamentale fournirait une meilleure assise à notre culture que celle offerte jusqu'ici par le travail.  相似文献   
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The US. and France have adopted contrasting models of motor fuel tax and highway finance policy. Fuel tax revenues are dedicated to state and federal highway funds in America, keeping taxes quite low, but preventing them from contributing to the general treasury. French motor fuel taxes are higher and make up nearly 11 percent of the central government's general revenues, excluding social security contributions. French highway finance relies heavily on tolls. Pressure from the US. federal deficit has reduced the highway trust fund's ability to protect highway spending from budgetary competition. Political and procedural changes in Congress make it likely that the U.S.will move away from exclusive dedication of motor fuel taxes.  相似文献   
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Decline and fall     
Kett JF  Cole TR 《美国史评论》1993,21(2):309-313
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