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《Marine Policy》2014
Papua New Guinea has sometimes been called the world's last frontier for relatively undamaged coral reefs and their resources. In 2007, the country joined its neighbours in the marine aquarium trade. By licensing a private company, Papua New Guinea tried an alternative approach to the introduction of this activity. Under the so-called SeaSmart Programme, over 100 fishers were trained in sustainable collection techniques and handling of organisms, until the programme was shut down in 2010, and replaced by its successor, EcoAquariums PNG. This article contains the first study on the introduction of the marine aquarium trade into Papua New Guinea. It evaluates the overall outcomes of the SeaSmart Programme, lists targeted species, and their prices. The main focus is on the local collectors, and on the impacts of this new activity on them and their communities. Benefits from collecting marine ornamentals are assessed and their contribution to household income is quantified. Perceptions on non-financial benefits of the SeaSmart Programme are also gathered. The empirical work was carried out between September 2010 and February 2011 in the Central Province of Papua New Guinea. A total of 199 fishers including 44 aquarium fishers were interviewed in eight different communities in the Central Province of Papua New Guinea. The results show that marine aquarium fishing does provide benefits to local resource collectors, but also that this “sustainable” way of collecting of marine ornamentals might lead to some depletion. 相似文献
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There have been comparatively few large-scale studies on spatial genetic structure of bathyal seafloor fauna, despite the importance of these data to the successful management of the world's oceans. We use a comparative analysis of mitochondrial DNA from five bathyal (200–3500 m) species of brittle-stars (Ophiuroidea) to assess phylogeographic structure along an extensive (8000 km) longitudinal gradient at temperate latitudes (28–56°S) from south-west Australia (113°E) to seamounts east of New Zealand (175°W). We found no evidence of a genetic discontinuity between Australia and New Zealand, either across the temperate Tasman Sea or across the Southern Ocean between the South Tasman Rise and the Macquarie Ridge. However, there were latitudinal phylogeographical breaks between tropical, temperate and polar regions; longitudinal breaks across the eastern Indian Ocean; and a bathymetric break at approximately 1700 m. Although there was limited regional structure in the frequency of haplotype distributions within the major clades, and no clade appeared to be strictly panmictic, the regional structure in general was not concordant with a simple isolation-by-distance model. Demographic structure varied with three clades having a simplified haplotype network, low effective population sizes and no evidence of significant population expansion, and two clades having a high diversity of haplotypes, relatively high effective population sizes and signs of recent population expansion. These results are discussed with respect to putative dispersal strategies. We hypothesise that the ‘brooding’ species produce both brooded young and pelagic larvae, allowing for both the maintenance of local populations and long-distance dispersal. 相似文献
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“Coastal squeeze” refers to the process in which coastal ecosystems are threatened by the combination of sea level rise (SLR) and the presence of a physical barrier, such as human infrastructure. This situation prevents the landward migration of ecosystems and species, as the coastline moves inland, and they are thus exposed to local extinction. Our objective was to explore coastal squeeze in the state of Veracruz, Mexico, through the study of urban expansion on the coast, an analysis of coastline geodynamics, and a projection of the potential effect of SLR on the distribution of two focal plant species which are endemic to the coastal dunes of Mexico. Urbanization of the coast, parallel to the shoreline, has been taking place increasingly rapidly, displacing ecosystems, both natural (mangroves, beaches and coastal dunes) and transformed (cultivated fields and pastures). Taking into consideration the geodynamic trends of the coastline and an analysis of its historical evolution, it can be seen that the coastal strip is eroding at rates that vary from slow to very rapid. Finally, the results of ecological niche modeling indicate that, under scenarios of SLR, the potential distribution of the two focal species would diminish: Chamaecrista chamaecristoides by 6–28%, and Palafoxia lindenii by 2–15%. These results indicate that “coastal squeeze” is likely in the study area, and that measures to limit or mitigate this process are required. Such measures could include urbanization programs which limit development to appropriate zones, the restoration and rehabilitation of deteriorated ecosystems and the conservation of those ecosystems which are still healthy. 相似文献
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A new species, Procretevania mitis sp. nov., is described from the Early Cretaceous of Yixian Formation at the Huangbanjigou, Beipiao City, western Liaoning, China. Based on new morphological data, a key of Procretevania Zhang and Zhang, 2000 is provided. Forewing venations, body and forewing lengths, localities and horizons of various genera of Evaniidae in amber and compression fossils are summarized for comparison. Evaniidae have a high degree of venational diversity, while more complex forewing venations for Lebanevania and Mesevania suggest that they may represent the stem group of the Evaniidae. High diversity of Evaniidae in the Early Cretaceous implies that Evaniidae might have radiated before the Early Cretaceous. Furthermore, comparison of body and forewing lengths of amber and fossil genera indicate that the amber specimens have relatively smaller size. 相似文献
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巴布亚新几内亚西部Fubilan山奥克泰迪矿床是一个世界级铜金矿床,在大地构造上位于新几内亚造山带的巴布亚褶皱带。该矿床的铜金矿化赋存于Fubilan二长斑岩及其周边的磁铁矿夕卡岩和硫化物夕卡岩中。矿石类型以原生硫化物矿石为主,金属矿物包括磁铁矿、黄铁矿、磁黄铁矿、白铁矿、黄铜矿、斑铜矿等。蚀变类型包括夕卡岩化、钾化、泥化和青盘岩化。矿床氧化次生富集带发育,表生矿石矿物为蓝辉铜矿、辉铜矿、自然铜、铜蓝和银金矿。成矿作用主要受区域构造、侵入杂岩体、Darai组灰岩地层、断裂等因素的控制。根据矿床的主岩、矿石特征、蚀变特征和控矿因素,认为该矿床成因类型属于较为典型的夕卡岩一斑岩型矿床。 相似文献
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美国是全球最大的移民接收国,墨西哥是美国最大的移民来源国,特殊的地缘关系和巨大的发展差距使众多墨西哥人移民美国。墨裔移民为美国提供了充足的劳动力,在美墨边境地区,移民集聚带动了两国边境地区的发展。但族裔矛盾始终是美国主要社会问题之一,特别是“9·11”事件后,少数族裔和非法移民问题加剧美国社会分裂和对立,成为美国国内政治博弈的焦点。基于区域地缘关系的视角来看,美国与墨西哥之间长期不对等的国际关系决定了跨国移民的流入状态和生存境遇,也是美国族群矛盾的主要原因之一。移民问题政治化将持续强化墨裔移民政策的不确定性,使移民个人与家庭面临更大的融入困难。 相似文献
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本文主要介绍了2013年中国土地学会学术年会上提出的15个重要观点,包括:新型城镇化是不以损害农民权益为代价的城镇化;不能因为二元经济结构以及土地用途管制制度存在问题,就剥夺了农民流转土地的权利;“法外经济”已呈燎原之势;在土地资源配置和权利配置中,应相机处理公平与效率的关系;注意区分两种性质的房产税;土地整治规划应是新农村建设的落地规划;建立耕、园、林、草大土地整治模式;探析生态用地内涵有利于将可持续发展观贯穿于规划的全过程;土地整治现场调查评价工作应当配备先进技术;结构方程模型为土地整治项目的社会效益评价提供了一种新的思路与方法;全排列多边形图示指标法适宜于作挂钩适宜性评价;开展城镇工矿建设用地整治应适时、适度、适量;货币补偿和提供新宅基地对农户行为具有明显的积极影响;土地整治公众参与不尽人意的四大原因;适时组建土地整治行业协会。 相似文献