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The palaeobiota from a middle to late Holocene succession in Tom Thumbs Lagoon, N.S.W., Australia, reflects a range of environmental conditions caused by sea-level changes and active estuarine sedimentation. At the base of the succession (~ ?0.4 m AHD) a thin bed, containing molluscs dated at 6.7 ka B.P. by radiocarbon and amino acid racemisation, and foraminifers is indicative of open estuarine conditions. From +0.35 m AHD towards the top of the sequence the charophyte Lamprothamnium succinctum occurs in subrecent deposits. This species is characterised here by statistical measurements, and new characters are described and illustrated. The charophytes record a drop in sea level and the establishment of a lower salinity artificial wetland. The investigation has also established that decalcification in charophytes can be related to acidification produced by the release of organic acids, aggravated after 1928 by anthropogenic pollution.  相似文献   
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A range of factors, including consumer concerns about food safety, the growing popularity of rural tourism and policy initiatives to promote endogenous rural development, is converging to promote a relocalization of food production and service provision, especially in those regions marginalized by the globalization of the food supply system. The recent outbreak of foot and mouth disease in the UK has starkly illustrated the fragility of localized systems which depend heavily on consumers travelling to them. Within such a context, the importance of successful marketing strategies has become even more apparent. This paper reports on a questionnaire survey which investigated promotional and marketing strategies among a diverse range of producers and service providers in marginal agricultural areas of the EU. The findings suggest that many producers are situated towards the "formal" end of a marketing continuum, whereby ability to promote quality products and services (QPS) lies with a range of intermediaries. This raises doubts about the future economic benefits of QPS, should current marketing structures persist. The discussion offers critical reflections on interdisciplinary and international research of this nature, and advocates further theoretical and methodological development in order to explore in more depth many of the aspects raised in this exploratory investigation.  相似文献   
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Cobble features near Terrace Bay, Ontario, traditionally described as 'raised beach ridges,' are investigated to establish the extent to which they exhibit characteristics substantiating the assumption of a wave-formed origin. Detailed examination of their plan orientation, profile, and pattern does indicate a wave-formed origin, with little evidence of shore ice activity during their formation or of sub-aerial modification since. Localized angular materials and topographic discontinuities suggest that surface morphology represents the compound effect of rare high magnitude storm wave events over the last three thousand years.
L'auteur étudie les formations de galets près de Terrace Bay, Ontario - ce qu'on désigne généralement comme des «cretes de plage soulevée≫ - afin d'établir dans quelle mesure elles présentent des caractéristiques qui permettent de justifier l'hypothèse selon laquelle elles seraient le résultat de Faction des vagues. De l'examen approfondi du plan vertical, du profil, et de la disposition des formations, on peut en effet conclure à une origine due à l'action des vagues; peu d'indices de l'action de la glace de rive durant la formation, ou de modifications subaériennes par la suite, ont été relevées. La présence de matériaux anguleux dans les environs et les discontinuités topographiques suggèrent que la morphologie de surface est le résultat de l'effet combiné, lors des derniers trois mille ans, de vagues de tempêtes exceptionnelles et d'une très grande puissance.  相似文献   
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Theories about subsystem activity typically focus on policy formulation processes. One causal model of public policymaking, the advocacy coalition framework, offers a potentially useful way to bridge the gap between policy formulation and implementation in examining subsystem activity. The purpose of this paper is to assess the analytical utility of the advocacy coalition framework by examining the stability of policy-producing coalitions over time in the face of implementation complexities. An analysis of the policy changes that occurred during the implementation of the Endangered Species Act vis-à-vis planning for the construction of the Bureau of Reclamation's Animas-La Plata water project is conducted. The analysis reveals how coalitions protect their policy core beliefs during technical disputes through the acquiescence of secondary aspects of belief systems.  相似文献   
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