共查询到20条相似文献，搜索用时 31 毫秒
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通过在三亚鹿回头岸礁区开展人类活动的现场调查,发现礁区目前人类活动主要为以船捕鱼钓鱼、个人涉水捕鱼、采挖螺贝和潜水为主的水域活动和以养殖、餐饮为主的沿岸活动;人类活动强度和分布密度保持较低水平,水下人类活动印迹反映出过去礁区相对较频繁的人类活动状况。认为人类活动是导致三亚鹿回头珊瑚礁衰退的主要原因。基于以往定性资料,利用层次分析法计算了人类活动影响因子权重,并根据人类活动等级估算其影响指数,评价人类活动对珊瑚礁的影响。结果显示,近40年来人类活动对三亚鹿回头珊瑚礁总体为负面影响,但影响程度呈下降趋势,其中,上世纪70、80年代人类活动负面影响大,90年代小,目前的负面影响程度较小。主要原因在于上世纪90年代建立的三亚珊瑚礁国家级保护区和珊瑚礁立法保护,以及逐步加强的日常管理和环保宣传。但当前珊瑚礁仍面临不断增加的各类污染物排放活动的巨大威胁。 相似文献
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Natural Resources Research - 相似文献
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Paul Farrimond 《Journal of Paleolimnology》2005,34(4):539-540
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Pulau (P.) Semakau comprises a narrow, low-lying island, surrounded by a wide fringing coral reef of late-Holocene age. The modern reef flat comprises a gently sloping surface related to modern mean low water neap tide level. Six sediment facies are recognised below the line of high water of which three, adjacent to the island, are composed of terrigenous minerals and rock fragments and three are autochthonous carbonates sediments developed since local sea-level still stand (c. 6,500 years BP). The fringing reefs of P. Semakau and Singapore differ from many of the reef forms recorded from Peninsular Malaysia waters and the Gulf of Thailand. The Singapore reefs have wide, well-developed intertidal reef flats, lack lagoons and reef crests, and have a very steep reef slope. In contrast to most other fringing reefs of the region, the Singapore reefs have developed in a low wave energy, meso-tidal environment lacking strong environmental gradients. 相似文献
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鹿回头岸礁处于比较平静的水动力条件下,自海向陆,可分出礁体生长带、外礁坪、内礁坪和海滩四个相带.沉积物的分布主要受水动力支配,沉积物粒匪分布和参数变化可以反映水动力条件的变化.通过对岸礁与陆源碎层物组成的无障壁海岸对比,进一步说明岸礁礁体生长带是重要的物源区,岸礁沉积物搬运的距离较短,且受生物、地形等因素的影响. 鹿回头岸礁沉积物的生物组分以软体动物壳屑为主,珊瑚屑次之,二者占总量的87.06%,再依次为钙藻、有孔虫、棘皮动物、苔藓虫和八射珊瑚骨扑.由陆向海,珊瑚、钙藻、有孔虫和苦藓虫层逐渐增加,软体动物壳层和八射珊瑚骨针则递减. 本区水尾岭上升礁剖面自下而上可分为原生礁、礁体生长带、礁坪和海滩四个相带,它代表了高海面渐进型序列. 相似文献
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Haverluk T 《The Journal of geography》1997,96(3):134-145
"In 1930, the majority of Hispanics were of Mexican descent and lived in the five Southwestern states of Arizona, California, Colorado, New Mexico, and Texas. After World War II the Latino migrant stream began to diversify and include large numbers of Caribbeans, and Central and South Americans who generally settled in the Eastern states and California.... The U.S. Hispanic population has increased from approximately one million in 1930, to approximately 32 million in 1997. County maps chronicle the changing distribution and numbers of Hispanics from 1850 to 1990." 相似文献
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Madeline Davey 《The Australian geographer》2014,45(2):131-145
The Great Barrier Reef (GBR), Queensland, Australia, is one of the most recognisable coral reefs in the world. In 1981 the reef was listed on the World Heritage List, to be preserved as an environmental asset of global significance for all people in perpetuity. The GBR is also a landmark Marine Protected Area (MPA) under the World Heritage Marine Programme. Yet management of this iconic property is not without controversy and in recent years a number of impacts, including coastal developments, increased shipping traffic and global warming, have all threatened the reef. Any breach of Australia's World Heritage obligation to protect and conserve the property may yet result in the GBR being placed on the World Heritage List in Danger. In light of the persistent controversy surrounding GBR management, this paper gives voice to the perspectives and values of stakeholders located in and around one site of controversy, Gladstone Harbour, in the southern section of the GBR World Heritage Area. We present the views of users directly exposed to the controversial port expansion development at Gladstone Harbour in the southern GBR to shed light on the importance of community perspectives in marine park management. Our findings show that local views act to reinforce the global environmental protection narrative which underpins the World Heritage (WH) system. In this study local and global values collide and, we argue, that overlooking the perspectives of users has potential deleterious consequences for WH marine site management. 相似文献
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Natural Resources Research - 相似文献
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Natural Resources Research - 相似文献
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徐闻县西岸珊瑚礁存在与发展的条件 总被引：1，自引：0，他引：1
本区珊瑚礁存在与发展的条件全面优良.首先它自身条件好,拥有丰富的、多样的现生的造礁生物,包括造礁格架生物、充填生物和粘结生物,构成了雄厚的物质基础.第二,它具备造礁生物生长的优良自然条件.本区属北热带,通常其水温、盐度、含沙量与透明度均适宜造礁石珊瑚生长.在全球变暖的情况下,冬季水温更暖,珊瑚免受冻死;夏季琼东上升流影响到本区,水温不致过热,利于珊瑚度夏.本区造礁珊瑚生长率和珊瑚礁堆积率均高于预测未来的海平面上升率,加上本区地壳微弱上升,本区珊瑚礁将随着海平面上升而长高.第三,本区社会经济条件尚好,可以同珊瑚礁协调发展.自然保护区的成立与升格,不断加强了管理工作,有利于珊瑚的正常生长.本区珊瑚礁是可持续发展的. 相似文献
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