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Fengcheng Peng Tianrong He Zhenji Li Mengyu Chen Xiaoli Qian Lingxia Zeng Yiyuan Xu 《中国地球化学学报》2018,37(4):526-536
Based on the analysis of the enrichment characteristics of Hg and MeHg in bird feathers from Caohai National Nature Reserve in Guizhou, the risks of Hg pollution to the birds from Caohai wetland have been evaluated. The total Hg content of bird feathers ranges from 40 to 5058 ng/g with an average of 924 ng/g. The content of MeHg is significantly correlated with total Hg (r = 0.68, p < 0.01), and the content are among 0.75 and 113 ng/g. The total Hg content in the birds feathers is significantly dependent on their feeding habits, which is mainly in accordance with the following rule: carnivorous birds > omnivorous birds that are mainly carnivorous > omnivorous birds that are mainly herbivorous. There are also differences in the Hg enrichment ability in the different parts of bird feathers, and the total Hg and MeHg content in the wing feathers are significantly higher than that in the other parts of feathers. The bioaccumulation coefficients of aqueous Hg and MeHg by bird feathers are 0.9 × 104–112.13 × 104 (mean value is 20.47 × 104) and 0.47 × 104–70.4 × 104 (mean value is 9.52 × 104), respectively. Although the whole Hg level in Caohai bird feathers is not too high, the Hg content in some carnivorous birds exceeds over or approaches the abnormal threshold when birds are breeding (5 μg/g), which indicates that the birds in Caohai wetland are faced with some risks of ecological Hg pollution. 相似文献
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海洋可再生能源产业发展前景广阔,构建我国海洋可再生能源产业统计指标体系是开展海洋可再生能源产业运行监测和评估的前提。文章概述国际和国内海洋可再生能源产业统计的现状,总结主要特点和问题;在明确统计范围、设计原则和数据获取途径的基础上,构建我国海洋可再生能源产业统计指标体系,其中综合发展统计指标体系包括基本情况、总体规模、技术装备、运营情况和科技创新5个一级指标和38个二级指标,产业链发展统计指标体系包括装置研发、电站设计、加工制造、配套材料和设备、海上施工以及咨询服务6个一级指标和31个二级指标;最后提出建立常态化统计制度、定期更新统计指标及其数据、建立数据库以及开展产业运行监测和评估的建议,以期为我国海洋可再生能源产业的发展、管理和政策制定提供参考。 相似文献
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《中华人民共和国海岛保护法》实施前,全国大约有3 000多个已开发利用无居民海岛,也称历史遗留用岛。研究发现,历史遗留用岛产生的原因集中在3个方面,制度不健全影响了历史遗留用岛管理的规范化;监管不到位助长了历史遗留用岛行为的盲目化;"管理意志"加剧了历史遗留用岛问题的复杂化。文章通过剖析历史遗留用岛问题的发展背景,梳理和总结历史遗留用岛问题的内涵和产生原因,分析历史遗留用岛问题所带来的所有者权益、海岛生态保护、海岛开发利用规范管理等各方面影响,从而确定一个解决问题的总体思路和基本原则,分类、分步进行解决。 相似文献
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中华绒螯蟹大水体高产育苗技术研究 总被引：1，自引：0，他引：1
中华绒螯蟹(Eriocheur Sinensis)俗称河蟹、毛蟹,为高等甲壳动物。中华绒螯蟹适应性强,价值高,风味独特,营养丰富,是一种极好的增养殖对象,也是水产品中出口创汇的主要品种之一。中华绒螯蟹的营养成分中蛋白质为14%,脂肪为5.9%,碳水化合物为7%,每100g蟹肉中维生素含量高达5960个国际单位,热量5.6×105J。近年来,我国河蟹养殖发展较快,苗种出现供不应求的局面,故人工育苗的产量急需提高。中华绒螯蟹育苗共分六期(Z1,Z2,Z3,Z4,Z5及大眼幼体),1998年,河蟹大水体人工育苗在注重高科技的前提下,使Z1变态Z2的成活率达到80%以上,Z1到Z4的成活率达到66.7%,Z1到M(大眼幼体)的成活率达到31.4%,单位水体出苗量8.94×104只/m3,出池的大眼幼体单位数量为7.84×104只/500g。 相似文献
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渤海湾盆地奥陶系潜山内幕油气成藏主控因素研究 总被引：6，自引：2，他引：4
本文的渤海湾盆地奥陶系潜山内幕是指有石炭系—二叠系覆盖的奥陶系潜山。潜山内幕多为单斜平行结构,储层基本为非均质"似块状结构"。古近系为主的烃源岩,通过控山断层的断面输油,形成"新生古储"的成藏模式。奥陶系潜山内幕成藏有四项主控因素,按重要程度依次为生烃灶供烃潜能、有效输烃窗口、优势输导通道以及储层裂缝发育。同时具备四项有利主控因素的潜山,油气富集规模较大。在生烃灶供烃潜能有利的前提下,其他三项主控因素之一为不利时,仍有成藏的可能,但规模一般较小。潜山内幕的储集空间以裂缝为主,裂缝的发育程度受构造和控山断层形态的影响,背斜构造、弧形断层、多向交切断层有利于裂缝的发育,而受直线型断层控制的潜山裂缝欠发育。 相似文献
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干涉点目标分析(IPTA)技术是一种新兴的In SAR形变测量技术。它克服了常规雷达差分干涉测量(DIn SAR)受失相干因素和大气延迟影响较大的问题。介绍了IPTA方法及处理流程,并对参数迭代估计、基线精化等关键问题进行了阐述。对加利福尼亚州安大略市的39幅ENVISAT ASAR数据进行IPTA处理,提取了2005—2010年间的地面沉降信息并进行了形变分析。结果表明,该方法在大范围地面沉降监测中应用效果良好。 相似文献
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作为我国周边的海洋国家,日本和越南都非常重视对边远海岛的管理,针对包括边远海岛在内的海岛开发与保护管理,建立了涵盖立法及相关配套政策在内的制度体系。通过规划管理等手段,促进边远海岛优势产业发展和资源环境保护,不断加大对边远海岛基础设施建设的投入,提高社会事业发展水平,鼓励居民到边远海岛定居,改善边远海岛人居环境,加强对边远海岛的实际管控,将边远海岛作为推动海洋经济发展的重要增长点和维护国家海洋安全的战略平台。这些经验为我国今后提高边远海岛管理水平,强化对边远海岛管控能力等方面具有借鉴意义。 相似文献
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Zhu Jichang Feng Youliang Meng Qing-Ren Wu Fengcheng Li Hao Liu Haitao Zhang Feipeng Wang Tianyu Wu Guoli Zou Caineng Zhu Rixiang 《中国科学:地球科学(英文版)》2019,62(11):1783-1804
We present the results of Mesozoic sequences of the Bohai Bay basin in North China, based mainly on geochronology and interpretations of seismic profiles and logging data. Five tectono-stratigraphic sequences are defined: Lower-Middle Triassic, Lower-Middle Jurassic, Upper Jurassic, Lower Cretaceous and Upper Cretaceous. Based on an analysis of detrital zircons, the clastic rocks recorded two intervals of Jurassic magmatic activity, during 180–175 and 160–152 Ma, which can be correlated to the Nandaling and Tiaojishan Formations in the Yanshan area, respectively. However, since Jurassic volcanic rocks have not yet been found in the Bohai Bay basin, we speculate that these two stages of activity were mainly concentrated around the periphery of the North China Craton(NCC) rather than within. Based on an analysis of zircons from volcanic rocks and pyroclastics, the early Cretaceous magmatism in the Bohai Bay basin can be divided into two stages, 125–120 and 110–100 Ma,which can be correlated to magmatism in the eastern part of the NCC. The zircon ages indicate an absence of volcanic activity during the late Tuchengzi and Zhangjiakou periods which may correlate to the uplift of the Bohai Bay basin in the late Late Jurassic. Comparison of the development of Mesozoic basins and sedimentary strata in the central-eastern part of Yanshan tectonic belt and the the Bohai Bay basin indicates that the two areas are generally comparable, but with substantial differences.The central-eastern part of the Yanshan structural belt lacks Early-Middle Triassic strata, and the Bohai Bay basin lacks late Jurassic-early Cretaceous strata. Based on research results from late Mesozoic sedimentary structures in the central and eastern parts of the Yanshan tectonic belt, we infer that episode A of the Yanshanian Orogeny was weak in the Bohai Bay basin and its periphery, while episode B of the Yanshanian Orogeny had a strong influence on the Bohai Bay basin and its periphery. The available data reveal differences in the expression of these episodes: the Bohai Bay basin is characterized by vertical uplift, and the northern margin of NCC is characterized by horizontal compression uplift. 相似文献