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101.
In this study we estimate diffusive nutrient fluxes in the northern region of Cape Ghir upwelling system (Northwest Africa) during autumn 2010. The contribution of two co-existing vertical mixing processes (turbulence and salt fingers) is estimated through micro- and fine-structure scale observations. The boundary between coastal upwelling and open ocean waters becomes apparent when nitrate is used as a tracer. Below the mixed layer (56.15±15.56 m), the water column is favorable to the occurrence of a salt finger regime. Vertical eddy diffusivity for salt (Ks) at the reference layer (57.86±8.51 m, CI 95%) was 3×10−5 (±1.89×10−9, CI 95%) m2 s−1. Average diapycnal fluxes indicate that there was a deficit in phosphate supply to the surface layer (6.61×10−4 mmol m−2 d−1), while these fluxes were 0.09 and 0.03 mmol m−2 d−1 for nitrate and silicate, respectively. There is a need to conduct more studies to obtain accurate estimations of vertical eddy diffusivity and nutrient supply in complex transitional zones, like Cape Ghir. This will provide us with information about salt and nutrients exchange in onshore–offshore zones. 相似文献
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The outstanding natural and cultural values of Cape York have been acknowledged for decades, but those decades have been characterised by deep conflict. Non-government organisation intervention in local politics has seen a forceful push for nominating some or all of the Cape York Peninsula as a World Heritage Site. We illuminate the authorised heritage discourse at work in heritage-making, and highlight contested issues of ownership, governance, authenticity, and value. These themes contribute to the possibility of marginalising the voices of local people who wish to contribute to heritage-making in Cape York. Politics infuses all aspects of heritage-making in Cape York, and the specific experiences on Cape York reflect larger political processes occurring in World Heritage discourse. The paper draws on interviews undertaken in May and June 2012. 相似文献
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John Holmes 《The Australian geographer》2011,42(1):53-68
Entrenched contests about the future of Cape York Peninsula's lands, waters and people have for long received national prominence. In the federal arena, this has climaxed with the campaign to overturn the State's declarations on wild rivers. Initially pursued as a means of influencing decisions on the determination of the government in a finely balanced federal parliament, it has been retained as an early test of the survivability of the minority Labor government. The peninsula's prominence is founded on its iconic conservation status and the continuity of Aboriginal occupance of their country, reinforced by the formidable capabilities of Indigenous and conservationist leaders. Contests are characterised by their complexity, durability and intractability. Contests are bedevilled by shifting alliances and schisms within Indigenous and conservationist constituencies. Increasingly potent is the schism between modernist/reformist/regionalist visions of Indigenous futures, forcefully presented by Noel Pearson against more traditionalist/localist visions held by many community leaderships. Other participants, notably conservationists, State politicians and bureaucracies have needed to align their policies around these contested visions. Over the last two decades, policies of State Labor governments have maintained some continuity, being pro-active on conservation goals, selectively supportive of Aboriginal advancement, necessarily passive in the determination of land claims, reactive in the resolution of land tenures and property rights, and inconsistent and ineffectual in conflict resolution and in providing leadership in shaping sustainable, multifunctional futures, attuned to the peninsula's unique challenges and potentials. 相似文献
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João Rocha José Brilha Maria Helena Henriques 《Proceedings of the Geologists' Association. Geologists' Association》2014
In the western coast of Portugal, Cape Mondego is a well-known set of outcrops due to its international stratigraphic relevance given by the establishment of two stratotypes: the Global Boundary Stratotype Section and Point (GSSP) for the base of the Bajocian Stage and the Auxiliary Stratotype Section and Point (ASSP) for the base of the Bathonian Stage. 相似文献
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从公共安全风险评估基本概念辨析入手,将公共安全风险评估指标体系分为风险源危险性、风险受体暴露、社区应对能力和居民风险认知4个层次,并通过突变级数法定量评估社区公共安全风险。以东莞市虎门镇赤岗社区为例对其进行了社区公共安全风险评估,利用归一公式进行综合量化递归运算,求出其风险综合评估值为0.295,表明该社区公共安全风险很低,社区公共安全很好。基于突变级数法的社区公共安全风险评估,从主观和客观两个层面选取评估指标,特别强调了居民风险认知的作用,并发挥了突变级数法的优势,评估结果可准确地反映社区公共安全状况。 相似文献