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91.
20多年来,中国海陆及邻域的地质地球物理调查在不断进步,尤其是海域取得很多新认识,但中国海陆及邻域的大范围编图,尤其是大地构造图,没有随之更新;中国海陆的编图还一直存在海陆不接、海域编图相比陆域落后的问题;亟需编制一幅中国海陆及邻域的大地构造图.1992年编制的"中国海域及邻区地质地球物理系列图"的大地构造图,运用以活动论为内涵的全球构造理论作为指导思想,对中国海区及邻域的大地构造特征做出了较好的诠释.最近,中国海陆地质地球物理系列图编制项目,把1:500万中国海陆及邻域大地构造格架图作为图种之一.在全球构造理论基础上发展而来的块体构造学说,作为本次编图的指导思想,根据其大地构造体系,板块和板块边界作为一级构造单元,块体和结合带(缝合带等)作为二级构造单元,结合系列图中重力图、磁力图、地质图等图件成果,以及最近的其他调查研究资料,完善了对特提斯在南海周边的界线、东海陆架的基底构造属性等认识,在研究区内共划分出了欧亚板块、菲律宾海板块和印度-澳大利亚三大板块,6个板块边界构造单元,30个块体、14个结合带和10个缝合带. 相似文献
92.
《Marine Policy》2017
New multi-sectoral policies with a regional implementation are developed when maritime states recognise the importance of managing the marine environment under an ecosystem-perspective rather than a use-perspective. In Europe, the Marine Strategy Framework Directive (MSFD) is the first attempt to promote an integrated management of the seas from the coastline to the limit of the Exclusive Economic Zone. This paper shows that, nine years from the MSFD adoption, there remain several ecological, economic, social and governance challenges. Using information gathered in a dedicated survey of the European Union Marine Strategy Coordination Group and in the recent literature the paper identifies the obstacles preventing a successful regional cooperation and policy integration. The survey indicates that the MSFD coordination structures are, in general, well-developed but there is an apparent lack of political will to coordinate actions at the regional level. Member States request greater flexibility to implement the Directive but they put their national interests before the benefit of a coherent and integrated approach for the entire region. Differences in budget, economic sector predominance, lack of staff and the MSFD short time-scale are identified as the factors that can hamper cooperation. These have produced recommendations of possible strategies for optimising regional coordination structures which respect the subsidiarity principle underpinning the MSFD. 相似文献
93.
Influence of macrofauna long-term natural variability on benthic indices used in ecological quality assessment 总被引:1,自引:0,他引:1
An essential prerequisite for the assessment of the ecological quality of marine ecosystems is the understanding of the natural variability and its effect on the performance of quality indices. This study is focused on the long-term natural variability of diversity, biotic and multimetric indices by using long-term macrofauna data of a coastal area in the southern North Sea (1978-2005). The univariate and most biotic and multimetric indices respond significantly on specific natural disturbance events such as cold winters, but the strength of response varied between indices as well as between events. As a result, the ecological quality status can decrease over a range of 3 (out of 5) classification units. The overall ecological quality was good to high, but an increase of indices occurred from the mid 1980s onwards due to changes in the climate regime. This long-term variability has to be considered within ecological quality assessment schemes. 相似文献
94.
Several biotic indices have been proposed for the assessment of the ecological status of benthic macroinvertebrates in marine waters, although none have been generally accepted. When it comes to assessing highly stressed natural environments, such as estuaries, the controversy and uncertainty is much higher than for any given normal index. In this article, we test the behavior and suitability of different biotic indices proposed under the perspective of the Water Framework Directive (S, H, AMBI, M-AMBI, BQI, W-statistic, Taxonomic distinctness) for the assessment of estuaries in northern Spain. The low species richness and dominance of a few tolerant species in the characteristic community of these estuaries presented a challenge to the application of the biotic indices tested. Combined approaches that integrate different aspects of water quality and ecosystem functionality could increase the reliability of the ecological assessment of these transitional waters. 相似文献
95.
Martinho F Viegas I Dolbeth M Leitão R Cabral HN Pardal MA 《Marine pollution bulletin》2008,56(11):1834-1843
The seasonal variation of five selected multimetric indices for the determination of the Ecological Quality Status (EQS) of transitional waters was evaluated, as well as the indices’ responses to an extreme drought event that occurred in 2005. The database used regards the Mondego River estuary, which was sampled from June 2003 to August 2006 on a monthly basis. Among the selected indices (EBI - Deegan et al. [Deegan, L., Finn, J.T., Ayvazlan, S.G., Ryder-Kieffer, C.A., Buonaccoesi, J., 1997. Development and validation of an Estuarine Biotic Integrity Index. Estuaries 30(3), 601-617], EDI - Borja et al. [Borja, A., Franco, J., Valencia, V., Bald, J., Muxika, I., Belzunce, M.J., Solaun, O., 2004. Implementation of the European Water Framework Directive from the Basque Country (northern Spain): a methodological approach. Marine Pollution Bulletin 48(3-4), 209-218], EFCI - Harrison and Whitfield [Harrison, T.D., Whitfield, A.K., 2004. A multi-metric fish index to assess the environmental condition of estuaries. Journal of Fish Biology 65, 683-710], EBI - Breine et al. [Breine, J.J., Maes, J., Quataert, P., Van den Bergh, E., Simoens, I., Van Thuyne, G., Belpaire, C., 2007. A fish-based assessment tool for the ecological quality of the brackish Scheldt estuary in Flanders (Belgium). Hydrobiologia 575, 141-159] and TFCI - Coates et al. [Coates, S., Waugh, A., Anwar, A., Robson, M., 2007. Efficacy of a multi-metric fish index as an analysis tool for the transitional fish component of the Water Framework Directive. Marine Pollution Bulletin 55, 225-240]), the EBI by Breine et al. (2007) was the only that evidenced clear interannual and seasonal variations. The EQS by the several indices ranged from “Low” to “High”, depending on the index considered, evidencing the high level of mismatch between indices. The results are discussed in the scope of the EU Water Framework Directive, regarding monitoring strategies, application of indices and EQS assessment. 相似文献
96.
97.
华夏地块前加里东期变质基底的年代构造格架 总被引:3,自引:0,他引:3
华夏地块的前加里东期变质基底大致可划分为三大构造展,主体为古元古代中条旋回的结晶基底和新元古代-早古生代的褶皱基底,局部存在裂谷环境下的中元古代变质岩石。大量的单颗粒钻石年龄和Sin-Nd同位素测年资料显示出华夏地块的古元古代岩石形成于2400~2000Ma,中元古代的岩石形成于1400~1000Ma,而新元古代-早古生代的地层大致形成于740~430Ma。中条运动是华夏地块一次重要的造壳运动,奠基了华夏地块结晶基底,晋宁运动使华夏地块的闽浙隆起区彻底固结,而加里东运动则使得整个华夏地块彻底固结。 相似文献
98.
大洋科学钻探计划是地球科学领域迄今为止历时最长、成效最大的国际科学合作计划。自1968年以来,先后经历了深海钻探计划、国际大洋钻探计划、综合大洋钻探计划和国际大洋发现计划4个阶段。进入国际大洋发现计划,IODP工作组两次发布科学框架,文章对两个科学框架进行了对比分析。大洋科学钻探的特点和发展趋势是坚持解决重大科学问题,由地球拓展到太阳系,重视技术和大数据,以及扩大社会影响和宣传。这给我国发起国际大科学计划提供了启示,一要注重科技创新,运用大数据等先进技术;二要加强科学管理,促进开放和共享;三要重视提升影响力,扩大宣传和影响。 相似文献
99.
《Geoforum》2016
In this paper we present the findings of a qualitative investigation of change trends in urban freight deliveries. The empirical material was gathered with urban freight (courier) company managers and drivers in Aotearoa New Zealand. It presents personal accounts of the everyday lived experiences of those intimately involved in the delivery of goods within the urban environment. Twenty-five interviews were conducted across four urban centres between June and September 2015. We use the four elements of the Energy Cultures Framework to explore what urban freight managers and drivers ‘have’, ‘do’ and ‘think’, and the pressures of an external context. Four interrelated themes are presented. 1. Online shopping and home deliveries, 2. Tracking and transparency, 3. New technologies, and 4. Meeting (changing) expectations, with evidence provided by way of verbatim quotations. The ‘mobility cultures’ concept is used to explore the relationships between the four themes, and to identify the key change trends that may affect the ability of the freight industry to contribute to a low-carbon transport transition. We conclude by signalling some policy implications and future research directions. 相似文献
100.
Knowledge systems are mechanisms that can drive climate adaptation through the pursuits of enhancing resource sharing, collaboration, and learning, while at the same time helping to develop trust and credibility among individuals and intuitions. While these goals are widely discussed, less is known about the activities and strategies that knowledge systems undertake to achieve these goals. We analyze the Global Framework of Climate Services (GFCS) as a knowledge system organized around the translation of weather and climate information for decision-making. The GFCS brings together the World Meteorological Organization, national meteorological and hydrological services, and some of the world’s largest multilateral scientific, humanitarian, and development organizations. Our analysis draws on key informant interviews, focus groups conducted in African countries, and an online survey of GFCS participants. We describe the main activities pursued by the GFCS that shaped the vision of climate services, built capacity in national climate adaptation, and created connections among diverse actors and organizations worldwide. We show how these activities generated tensions about the purpose of the GFCS and how influence among the knowledge system was distributed. Based on our results, we illustrate new ways to conceptualize the strategies of knowledge systems, which we describe as (1) theorizing the norms of practice and mechanisms of change, (2) legitimizing actors, and (3) managing knowledge. These strategies identify pathways for, and pitfalls to, a knowledge system’s pursuit of its goals, providing guidance to managers of knowledge systems and an analytical framework to evaluate their impacts. 相似文献