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On 1 December 2007, eight ‘Small Island Developing States’ in the Western and Central Pacific Ocean implemented a management regime restricting the total number of days fished by tuna purse seine vessels within their waters, commonly referred to as the Vessel Day Scheme (VDS). The VDS is seen as one component of management arrangements to reduce fishing mortality on bigeye and yellowfin tuna, constrain fishing effort, and increase the rate of return from access fees by Distant Water Fishing Nations.  相似文献   
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A two-dimensional finite element model for density dependent groundwater flow was calibrated to simulate sea water intrusion in Nauru Island in the Central Pacific Ocean. Nauru Island occupies an area of 22 km2 and supports a population of 8500. The island has been mined for its phosphate deposits and current reserves indicate that the mine has about eight years life remaining. The water supply of the island is about one third dependent on imported water which is also used as ballast on the phosphate ships. Imported water will not be available in the future, and a hydrogeological investigation shows that the island is underlain by a fresh water layer, less than 5 m thick. The freshwater layer overlies a thick transition zone of brackish water which in turn overlies sea water. Simulation of several management options shows that it is possible to substitute current importation of fresh water by careful extraction from the groundwater resources of the island.  相似文献   
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Australia's border enforcement strategies and immigration control policies operate in distant geographies, concealed from human rights groups, media and the public. From offshore detention to militarised maritime defence operations, Australia's exclusion of asylum seekers is increasingly dependent upon geographical processes that ensure asylum seekers do not have access to the state's systems of protection. This article explores a critically overlooked geopolitical strategy of mobility regulation that relies on processes simultaneously expanding geographies of control, while contracting spaces of rights. The outcome of these rapidly evolving bordering practices is the exaggeration of the distance separating asylum seekers from the state, suspending them within a space devoid of an operational system of rights, and emphasising a new and restructured maritime legal geography.  相似文献   
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Nauru once possessed the world's purest deposits of rock phosphate, the precursor of the agricultural fertiliser, superphosphate. This resource was almost entirely depleted during the 20th century, mainly destined for Australia and New Zealand, where it played a critical role in the economic, social and demographic development of these nations and their biological transformation to outposts of temperate Northern Hemisphere flora.

By the early 1990s, the primary phosphate that had once blanketed the island had been almost completely removed, exposing a dramatic buried landscape of karst pinnacles and transforming Nauru into the world's most environmentally altered nation. Investigations into the rehabilitation of the mined-out area began in 1953, but all rejected the idea of restoration on the grounds of expense. In 1993, Nauru won an out-of-court settlement of A$135 million from Australia for restitution of the phosphate lands. No rehabilitation has yet taken place, however, and the project is unlikely to succeed. The soil stockpiled for the project is inadequate in quantity, in fertility, in elemental composition, in water retention capacity, and contains toxic levels of cadmium. Rainfall is too unreliable to support regular cultivation and the Nauruans possess no tradition of agriculture.

One alternative to rehabilitation is to exploit the terrain that has been exhumed from beneath the phosphate overburden. This closely resembles the Nauruan landscape of a quarter of a million years ago, before humans arrived and before phosphate buried the land. Such spitzkarren landscapes elsewhere in the tropics are venerated as landscape wonders and revered as scientific marvels. They are protected by World Heritage status and receive millions of visitors a year. The end of mining in Nauru is meanwhile leading to the re-establishment of an ecologically valuable and visually striking indigenous vegetation. This spectacular new landscape should be preserved, not destroyed, and exploited as a global travel destination.  相似文献   

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