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J.M.B. SMITH 《Geographical Research》1996,34(2):225-236
Erythrina variegata, E. insularis and E. vespertilio (the last two possibly conspecific) are native in Australia, and E. fusca occurs as viable seeds in sea drift on Queensland beaches. Higher diversity elsewhere suggests an extra-Australian origin, with dispersal to Australia by sea drift or birds. At least two introduced ornamental species, E. crista-galli (native to South America) and E. X sykesii (a sterile hybrid), have become naturalised. Erythrina crista-galli has become abundant on the Wilson-Richmond floodplain, NSW. Its seeds germinate progressively over three years, and may be dispersed by floodwaters. As well as being perceived locally as invasive weeds, naturalised Coral-trees also have conservational value, particularly with regard to nectarivorous birds. 相似文献
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NICOLA SMITH 《Geographical Research》1995,33(1):6-18
Since the early 1970s the Avoca River catchment has experienced a marked increase in all discharges, particularly high magnitude ones. This results from a change in the rainfall/runoff relationship, which is probably due to rising groundwater tables. Since 1973 the frequency of flooding in the lower Avoca, Loddon and Avon-Richardson catchments has increased markedly, placing pressure on downstream flood mitigation and irrigation works, as well as contributing to the degradation of environmentally sensitive wetlands. It also has the potential to exacerbate rising groundwater/salinity problems of the lower catchments. Human interference and changes in the rainfall regime are assessed to explain the nature of the apparent change in streamflows of the Avoca River catchment. 相似文献
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Since 1996, a broad range of publications has been produced by Canadian geomorphologists and hydrolo‐gists. These publications have been distributed in journals with national and international circulations. Although there remains a major focus on the study of observable processes in fluvial, aeolian, coastal and slope environments there is also a strong, historical component to explanations oflandforms, landform assemblages and sedimentary sequences. Some of these histories have incorporated the effects of high‐magnitude (catastrophic) events, some of which may have no modern analogues. Perspectives on the interactions among microclimatic variables, including changes induced by human actions, continue to evolve. Forest clearance and its effects on evaporation rates, water‐table levels and timing ofsnowmelt, the human use of wetlands and release of methane and carbon dioxide, will continue to demand the attention of scholars interested in explaining future climatic scenarios. Depuis 1996, un large éventail de publications a été produit par les géomorphologues et hydrologues du Canada. Ces travaux ont été diffusés dans des revues nationales et internationales. Bien qu'il y ait encore une attention privilégiée portée à l'étude des processus observables dans des environnements fluviaux, éoliens, côtiers et de pente, il existe aussi une importante composante historique dans l'explication des formes du paysage et de leurs assemblages ainsi que des séquences sédimentaires. Certaines de ces reconstitutions historiques ont incorporé les effets d'événements de haute magnitude (catastrophique), dont certains n'ont peut‐être pas d'analogues modernes. Les points de vue sur les interactions entre les variables microclimatiques, et notamment les changements d'origine anthropique, continuent d'évoluer. Le recul des forêts et ses effets sur les taux d'évaporation, le niveau des nappes phreatiques et le calendrier de la fonte des neiges, l'utilisation humaine des zones humides et l'émission de méthane et de gaz carbonique, continueront d'exiger l'attention des spécialistes qui se penchent sur l'explication des scénarios climatiques futurs. 相似文献
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Summary. In this paper we discuss 26 new Neolithic AMS dates obtained from human and animal bone from four previously undated funerary monuments in the Cotswold-Severn region. By strategically targeting particular portions of these skeletal assemblages, a number of valuable inferences are made concerning the extent of variation in apparently co-existing burial practices both within and between monuments. Of particular interest is the observation that variations in the extent to which interments have become disarticulated cannot necessarily be equated with chronological relationships regarding their deposition. This project has also obtained dates from cremated bone, which establish that the range of funerary treatments in practice during the earlier Neolithic also included cremation. Additionally it is observed that whilst some, apparently primary, deposits may in fact be later insertions, other material in apparently secondary contexts may actually return earlier Neolithic dates. 相似文献
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The authors compare the solidarity practices of farmers and food activists in Croatia and Italy in order to highlight the unintended consequences of mutual support initiatives and how these may reinforce disengagement from governance. Two ethnographic case studies from Istria (Croatia) and Lombardy (northern Italy) show self-reliant ways of organizing mutual support networks among, respectively, Istrian winemakers and Lombard Solidarity Purchase Groups. They both challenge the top-down regulatory governance of food systems, with the former organizing forms of economic and logistic mutual support to bypass strictures and faults of the Croatian fiscal and agricultural aid system and the latter self-certifying organic crops to avoid the costs and arbitrariness of bureaucratic procedures for organic certification. Both highlight the discourse and practice of morality in food procurement and the ambivalence of the concept and practice of ‘solidarity’. 相似文献