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1.
ABSTRACT

Attending to Poly-Olbion’s river dynamics, I argue that, implicitly opposing natural, inevitable unionization, Drayton demonstrates through visual and poetic means that any viable empire is forged by deliberate local choices about conjunction and affiliation. Further, I show that by reconfiguring Saxton’s maps, rejecting politically defined boundaries and perceptions, and situating three major rivers as the organizing features of the landscape and the empire, Drayton ultimately defines Britain as inherently and universally maritime. Moreover, linking Poly-Olbion to mare clausum and mare liberum debates, I reveal that Drayton situates the flow of self-aware rivers into the sea as an extension of Britain beyond its land boundaries. He thereby suggests that the eventual mixing of British waters with the larger oceans establishes the basis of Britain’s local and global maritime rights, linking regional autonomy and conjunction by choice with claims to both local offshore dominion and global freedom of navigation and trade.  相似文献   
2.
Invasive vegetation species can lead to major changes in the geomorphology of coastal systems. Within temperate estuaries in the southern hemisphere, especially Australia and New Zealand, the cordgrass Spartina spp. has become established. These species are highly invasive, and their prolific growth leads to the development of supratidal environments in formerly intertidal and subtidal environments. Here, we quantified the impact of Spartina invasion on the geomorphology and sequestration capacity of carbon in the sediments of Anderson Inlet, Victoria, Australia. Spartina was first introduced to the area in the 1930s to aid in land reclamation and control coastal erosion associated with coastal development. We found that Spartina now dominates the intertidal areas of the Inlet and promotes accretion (18 mm/year) causing the formation of over 108 ha of supratidal islands over the past 100 years. These newly formed islands are calculated to potentially contain over 5.5 million tonnes of CO2 equivalent carbon. Future management of the inlet and other Spartina‐dominated environments within Australian presents a dilemma for resource managers; on the one hand, Spartina is highly invasive and can outcompete native tidal marshes, thereby warranting its eradication, but on the other hand it is likely more resilient to rising sea levels and has the potential for carbon sequestration. Whether or not the potential advantages outweigh the significant habitat change that is anticipated, any management strategies will likely require additional research into costs and benefits of all ecosystem services provided by Spartina including in relation to nutrient cycling, shoreline stabilisation, and biodiversity as well as in response to the longevity of carbon found within the sediments.  相似文献   
3.
一场甲午战争,使东亚海权格局剧变,由此构成中日两国命运变化的历史拐点。战前,中日两国面对西方殖民扩张的相同遭遇,展开了近30年的海军现代化建设,并在互为敌手的竞争中日益凸显于以英国为主导的东亚海权格局之中。然而,不同的战略选择决定了不同的命运,甲午战争用血与火诠释了海权与海防的本质区别及其决定性影响。正因为战败后的中国已完全置身于东亚海权格局之外,再次陷入有海无防的境地,导致海权得以坐大的日本推行"大陆政策"更加有恃无恐,在列强瓜分中国的狂潮中走上独霸东亚之路。  相似文献   
4.
This paper examines the theory and practice of the maritime cultural landscape in general, and projects the theoretical concepts and aspects involved on the highly dynamic late medieval north‐eastern Zuiderzee region in the Netherlands. The cultivation of land and marine erosion (floods and rising sea level) are considered as the main factors that caused the transformation of the physical landscape of this region from peatlands with freshwater basins into a tidal lagoon. As a consequence, multiple settlements drowned, large areas of land submerged, and culture and the landscape gradually became more maritime, giving the research area a cultural identity and dimension.  相似文献   
5.
Tupaia’s Map is one of the most famous and enigmatic artefacts to emerge from the early encounters between Europeans and Pacific Islanders. It was drawn by Tupaia, an arioi priest, chiefly advisor and master navigator from Ra‘iātea in the Leeward Society Islands in collaboration with various members of the crew of James Cook’s Endeavour, in two distinct moments of mapmaking and three draft stages between August 1769 and February 1770. To this day, the identity of many islands on the chart, and the logic of their arrangement have posed a riddle to researchers. Drawing in part on archival material hitherto overlooked, in this long essay we propose a new understanding of the chart’s cartographic logic, offer a detailed reconstruction of its genesis, and thus for the first time present a comprehensive reading of Tupaia’s Map. The chart not only underscores the extent and mastery of Polynesian navigation, it is also a remarkable feat of translation between two very different wayfinding systems and their respective representational models.  相似文献   
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7.
A robust debate among coastal geomorphologists as to the processes by which beach‐ridge plains around Australia have formed was initiated by a former President of the Institute of Australian Geographers. This review gives special consideration to the work of Jack L. Davies, whose academic contributions to coastal geomorphology in Australia have not always been appropriately acknowledged when explaining how similar plains have evolved elsewhere in the world. Davies recognised that relatively steep storm waves caused erosion (cut) on beaches, whereas less steep long‐period swell waves returned sand (fill). He considered the beach berm to be the nucleus on which a beach ridge formed, which could subsequently develop into a foredune, in contrast to cobble ridges that were deposited during storms. Offshore conditions regulate supply of sand to the shoreline, partly through effects on wave refraction, with higher rates of supply where the nearshore is shallow. It was apparent to Davies that the elevation of successive ridges might, but not necessarily, provide evidence of past changes of sea level, despite adornment by variable amounts of windblown dune sand. Morphodynamic understanding of long‐term coastal evolution, based on radiocarbon dating chronologies, has demonstrated that Australian coastal plains formed over the past ~6,000 years when sea level has been close to its present level, in contrast to several documented locations in the northern hemisphere where the sea has been rising for the past few millennia. Particularly insightful were observations by Davies that ridge formation could be influenced by a range of factors including changes in sea level, storminess, or sediment supply. These factors acting singly or in combination seem likely to change in the future. Understanding such responses remains a high priority and can be addressed by new technologies, such as light detection and ranging, optically stimulated luminescence dating, ground‐penetrating radar, and computer simulation.  相似文献   
8.
东北亚国家对于海洋权益的认知渐进深入,以及地缘政治实况和国家实力消长等,构成了社会意识与物质力量变迁的合力,加剧了日本与周边国家之间普遍存在海洋领土争端这一社会情势。当代西方国际关系理论中的建构主义为上述实况提供了一种新的思维尝试、分析框架与消解困境的方案补充。东北亚海洋领土争端困境的解决关键在于如何利用预留的政治空间。  相似文献   
9.
This paper describes the hitherto unreported occurrence of mid‐Holocene mangrove deposits in the Richmond River estuary, southeastern Australia, thereby providing evidence for changes in the distribution and composition of mangrove communities within a subtropical estuarine system during the Holocene. Stratigraphic, radiocarbon and palynological evidence indicates that widespread development of mangrove communities took place in the upstream reaches of the Richmond River estuary during the period 7000 to 6000 years BP. These communities maintained their habitat through substrate aggradation under the conditions of a moderate sea‐level rise, in contrast to other estuaries within the region, which generally experienced the submergence of intertidal substrates. Mangrove species belonging to the family Rhizophoraceae, most likely Bruguiera gymnorrhiza and Rhizophora stylosa, dominated these communities, in strong contrast to contemporary communities, which are dominated by Avicennia marina. Moreover, these mid‐Holocene communities were located a considerable distance upstream of the contemporary occurrences of Rhizophoraceae species within the estuary. The changes in the spatial distribution and composition of mangrove communities parallel the large‐scale evolution of the estuary driven by sea‐level variation. Shallow, buried Pleistocene terraces probably contributed to the regionally unique aggradational response of the mangrove communities and their substrates to a sea‐level rise during mid‐Holocene times.  相似文献   
10.
关于当代中国边疆研究中的几个问题   总被引:1,自引:0,他引:1  
关于边疆的界定问题 ,在 2 0世纪 90年代以前 ,我们往往只提陆疆 ,在这以后有所改变 ,增加了海疆的概念。我们在观察边疆地区的时候一定要历史地看 ,中国疆域的历史发展呈现出延续性和波动性相结合的特点。边疆的重要战略地位不仅体现在边疆地区是国防的前线、改革开放的前沿 ,还体现在边疆地区的稳定与发展是我国可持续发展的重要保证  相似文献   
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