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Part of a broader interest in the escalating securitization of conservation practice, scholars are beginning to take note of an emerging relationship between conservation–securitization, capital accumulation, and dispossession. We develop the concept of accumulation by securitization to better grasp this trend, positioning it in the critical literatures on neoliberal conservation, green grabbing, and conservation-security. The concept captures the ways in which capital accumulation, often tied to land and resource enclosure, is enabled by practices and logics of security. Security logics, moreover, increasingly provoke the dispossession of vulnerable communities, thereby enabling accumulation. We ground the concept by turning to the Greater Lebombo Conservancy (GLC) in the Mozambican borderlands. This is a new privately-held conservancy built as a securitized buffer zone to obstruct the movement of commercial rhino poachers into South Africa’s adjacent Kruger National Park. We show how wildlife tourism-related accumulation here is enabled by, and in some ways contingent upon, the GLC’s success in curbing poaching incursions, and, relatedly, how security concerns become the grounds upon which resident communities are displaced. In terms of the latter, we suggest security provides a troubling, depoliticized alibi for dispossession. Like broader neoliberal conservation and green grabbing, we illustrate how accumulation by securitization plays out within complex new networks of state and private actors. Yet these significantly expand to include including security actors and others motivated by security concerns.  相似文献   
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The limited precious coral (Coralliidae) resources in the Northwestern Pacific have been managed by Taiwan with a comprehensive management plan, by Japan with a strengthened set of management measures, and by China through the listing of such coral as a Category I national treasures. However, continuous increases in coral consumption and coral prices have stimulated overexploitation and poaching of the resource, and hence have undermined the effectiveness of these management schemes. This article discusses the current precious corals supply chain and suggests that the rise of China in purchasing substantial amounts of coral products was the underlying cause for overexploitation and poaching. Several gaps in the management schemes are also identified and discussed. The article finally concludes that there is an urgent need for establishing a cross-disciplinary integrated conservation policy and a regional management platform consisting of the three participating states to address all the relevant social and ecological issues.  相似文献   
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利用5头活动于南极普里兹湾的象海豹携带的CTD观测获得的2011年3—6月埃默里冰架前缘冰间湖区域海水温盐剖面数据, 研究了该海域上层水体结构在初冬的演化过程。结果显示, 可将该演化过程分为三个阶段:第一阶段海水温度从层化到均匀, 3月下旬次表层仍维持暖水特征, 随着表层海水冷却作用, 次表层暖水逐渐消失, 上下水体温度趋于均匀并接近冰点, 温度剖面从“逆温型”演变到“均匀型”; 第二阶段海水盐度从层化到上下均匀, 也就是从“均匀型”演变到“渐变型”, 海水结冰析盐过程使上层海水盐度增加, 增强垂直对流混合, 上下层盐度达到均匀; 第三阶段冷却结冰持续, 海水盐度继续增大, 形成盐度随深度减小, 温度随深度增大的“渐变型”结构。根据温盐剖面数据计算三个阶段的海-气之间的热通量分别是-90.93、-82.20和-43.44 Wm-2。考虑海水盐分的增加主要源于海冰形成, 由此推算三个阶段内平均的海冰形成速率分别是5.4、4.9和2.5 cm d-1。在南极初冬时期, 随着海水上层低温高盐化演变持续, 海水向大气释放的热通量逐渐减少, 海冰形成速率也呈减少趋势。  相似文献   
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皱饰构造研究进展综述   总被引:1,自引:0,他引:1  
在综述皱饰构造成因研究历程和国内外最新研究成果的基础上,总结评述了 4种有代表性的皱饰构造形成模式,其核心问题是在皱饰构造的形成过程中微生物席和物理作用的参与方式,以及受造席者、透光性、水动力条件、基底类型和生物扰动五大因素的影响程度.在对皱饰构造和现代微生物席对比研究的基础上,发现皱饰构造与微生物席的分布在很大程度上具有一致性,所以通过对现代微生物席的生长发育环境进行综合研究,推测了有利于皱饰构造发育的古环境.皱饰构造一般发育于潮间坪和滨外过渡带,并且在显生宙一般与生物扰动作用具有不相容性.皱饰构造是发育最普遍、受关注最广泛的保存在硅质碎屑岩中的微生物诱导形成的原生沉积构造,所以理清皱饰构造的成因模式及古地理分布,有利于碎屑岩微生物席学的发展,可以为理解硅质碎屑岩中的特殊沉积构造提供重要线索.  相似文献   
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The eastern South Pacific southern elephant seal population was extinguished by extensive hunting and the current presence of this species in this area is not well understood. We reviewed existing records from the 1900s to 2014 in the eastern South Pacific, as well as tagged seals and movement records in order to assess the potential immigration source of these individuals. A total of 409 confirmed sightings were compiled, ranging from the southern tip of South America (Cape Horn Archipelago) as far north as Ecuador, including some oceanic island groups. The evidence shows also that recolonisation of its former Pacific distribution has started, with slow population growth in three incipient pupping sites in southern Chile (south of 51°S). Although the source of all of the individuals in the growing colonies is unknown, evidence from tags and satellite tagging indicates that some seals come from subpopulations on the Peninsula Valdes and the Falkland/Malvinas Islands, although mtDNA analysis showed, preliminarily, a greater genetic relationship only with the Falkland/Malvinas Islands rookery.  相似文献   
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