THE POSITION AND ROLES OF PORTS AND RAILWAYS IN THE EURASIA LAND BRIDGE TRANSPORTATION IN NORTHEAST CHINA     

叶宝明  李文杰 《中国地理科学(英文版)》1992,2(3):235-244

This paper systematically analyzes and proves the favorable factors of utilizing the ports and the railways in Northeast China for the Asia-Europe land bridge transportation. It will be more beneficial to Dalian Port and HaDa (Harbin-Dalian) and Binzhou (Harbin-Manzhouli) railways in Northeast China to the Siberia railway in Russia than 1) to other ports and the corresponding railways in China, 2) to the Nakhodka Port in Russia and the corresponding railways and 3) to the Chongjin Port in North Korea and the corresponding railways. This paper also puts forward the reform measures to adopt the ports and the railways in the northeast region in China for the land bridge transportation and the problems in transportation policies and management systems.  相似文献   

North European last glacial–interglacial transition (LGIT; 15–9 ka) tephrochronology: extended limits and new events     

C. S. M. Turney  K. Van Den Burg  S. Wastegrd  S. M. Davies  N. J. Whitehouse  J. R. Pilcher  C. Callaghan 《第四纪科学杂志》2006,21(4):335-345

High‐precision correlation of palaeoclimatic and palaeoenvironmental records is crucial for testing hypotheses of synchronous change. Although radiocarbon is the traditional method for dating late Quaternary sedimentary sequences, particularly during the last glacial–interglacial transition (LGIT; 15–9 ka), there are inherent problems with the method, particularly during periods of climate change which are often accompanied by major perturbations in atmospheric radiocarbon content. An alternative method is the use of tephras that act as time‐parallel marker horizons. Within Europe, numerous volcanic centres are known to have erupted during the LGIT, providing considerable potential for high‐precision correlation independent of past radiocarbon fluctuations. Here we report the first identification of the Vedde Ash and Askja Tephra in Ireland, significantly extending the known provenance of these events. We have also identified two new horizons (the Roddans Port Tephras A and B) and tentatively recognise an additional horizon from Vallensgård Mose (Denmark) that provide crucial additional chronological control for the LGIT. Two phases of the Laacher See Tephra (LST) are reported, the lower Laacher See Tephra (LLST) and probably the C2 phase of the Middle Laacher See Tephra (MLST‐C2) indicating a more northeasterly distribution of this fan than reported previously. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

渤海湾曹妃甸深槽海区地形地貌特征及控制因素   总被引：2，自引：2，他引：0  

褚宏宪  史慧杰  宗欣  高小惠  方中华  刘晓东 《海洋科学》2016,40(3):128-137

通过研究浅层地震剖面、侧扫声纳和水深地形等数据资料,得出,曹妃甸沙岛的岬角地貌引起深槽海域局部潮流流速增大,甸头前沿深槽区以冲刷为主,最大水深达42 m,刷新了渤海湾最大水深记录,深槽部位的侵蚀量最大,深槽南坡冲刷幅度大于北坡,工程建设后期深槽区侵蚀冲刷程度有变小变缓趋势。早期深槽的形成是由于浅部断层受深部构造影响发生阶梯状错断沉陷,海底地层形成古凹槽,但深槽海底地层沉陷速率略大于沉积速率,使得深槽海域长期保持了渤海湾最大的水深环境。初步得出在历史时期曹妃甸深槽经过2万a以上长期存在,深槽的走向经历了南北向-北东向-北西向的转化过程。认为地质构造、古滦河三角洲演变、海洋水动力作用和人类活动等内外营力作用共同控制了曹妃甸海区地貌体系的发育与演化。达到了研究渤海湾曹妃甸深槽海区地形地貌控制因素和深槽的地质演化的目的,为曹妃甸港的规划、运营期维护和未来发展提供科学依据具有重要意义。  相似文献   

射阳港近岸海域沉积物特征及冲淤趋势     

汤倩  闫玉茹  王敏京 《江苏地质》2021,45(3):283-289

海岸是陆地与海洋相互接触和影响的地带,通常指受波浪和潮汐等海洋动力作用的沿岸地带,同时也是人类社会经济发展的重要地带,大型人类工程往往会对其短期地貌变化和沉积物特征产生巨大影响。沉积物粒度分析是研究海洋沉积作用及过程的一个基础的、重要的方法,通过射阳港海岸动力地貌调查,研究了射阳港区不同时期的水下沉积物分布特征,将不同历史时期海图的等深线对海床冲淤变化进行对比分析,认为双导堤完工后导堤口区域出现了明显冲刷,导堤两侧出现淤积,沉积物颗粒变细,表明港口工程等局部影响因素会在短期内显著改变水动力地貌。  相似文献   

Distribution and possible sources of organochlorine residues in sediments of a large urban estuary,Port Jackson,Sydney     

G. F. Birch  S. E. Taylor 《Australian Journal of Earth Sciences》2013,60(4):749-756

Sydney Harbour is surrounded by a large capital city of about four million people and its highly urbanised (86%) catchment supports a substantial industrial base and an extensive transport infrastructure. Large commercial and naval ports occupy the waterway and the harbour is an important recreational area. Surficial sediment in Sydney Harbour contains high concentrations of PCBs, HCB, total chlordane, total DDT, aldrin, dieldrin, heptachlor and heptachlor‐epoxide, but low concentrations of lindane. PCBs, total chlordane, and to a lesser extent dieldrin, are most elevated in sediment in creeks on the southern shores of the harbour suggesting sources within older, highly urbanised/industrialised catchments of western‐central Sydney. There are high concentrations of total DDT and HCB in sediments of the upper harbour and Homebush Bay suggesting that chemical industries on the shores of the estuary in this area are sources of these contaminants. Although no sediment quality guidelines apply in Australia, empirically derived biological effects criteria suggest that sediment over extensive areas of Sydney Harbour may have an adverse impact on biota. Especially of concern are sediments containing high concentrations of chlordane and DDT.  相似文献   

马尼拉海湾和莱城港湾的辐射状况     

姚兰昌  蔡英 《高原气象》1991,10(4):351-361

本文利用在马尼拉海湾和莱城港湾考察所获得的少量辐射资料,分析了该两地区辐射各量值的日变化特征和地区差异。揭示了海(港)湾水面及其紧邻海岛陆面的辐射特征差异。这些信息很可能有助于上述地区海洋大气间热量交换的分析计算。  相似文献   

渤海湾曹妃甸港区开发对水动力泥沙环境的影响   总被引：4，自引：3，他引：4       下载免费PDF全文

陆永军  左利钦  季荣耀  张金善 《水科学进展》2007,18(6):793-800

针对渤海湾曹妃甸海域波浪、潮流、泥沙及海床演变特点,应用波流共同作用下二维泥沙数学模型研究港区开发方案。2006年冬季和夏季大、小潮潮流泥沙验证表明,该海域潮位及15条同步垂线流速、流向、含沙量过程的计算值与实测值吻合良好,并进行了矿石码头港池前沿海域在潮流与波浪共同作用下悬沙引起的冲淤验证,计算的冲淤厚度及其分布趋势与实测值比较接近。在此基础上,研究了曹妃甸前岛后陆的港区围垦方案对水动力环境的影响问题,包括该工程引起的曹妃甸甸头以南深槽、老龙沟深槽及各港池的流速变化及底床的冲淤变形等。  相似文献   

福建港口体系结构研究   总被引：2，自引：0，他引：2  

陈斓  伍世代  陈培健 《热带地理》2007,27(3):249-253,283

阐述了福建港湾自然条件和港口开发现状,采用赫希曼-赫芬达尔指数分析近20年来港口体系空间结构的动态演变规律,结果表明,福建港口体系空间结构演变总趋势呈分散化。这说明了港口间的竞争大于合作,职能结构趋同,因而形成合理分工与协作的福建港口群是当务之急。鉴于此,运用模糊聚类、货种区位商等分析技术,对其体系内的港口等级层次、职能结构的基本特征进行探讨,并在此基础上提出了各港口职能分工的发展方向。  相似文献   

Identifying substandard vessels through Port State Control inspections: A new methodology for Concentrated Inspection Campaigns     

《Marine Policy》2015

Substandard vessels that fail to comply with international maritime regulations are the target of Port State Control inspections. Despite their significant costs, many inspections do not lead to any detentions and, in a significant number of cases, no deficiencies are detected. In this paper, quantile regressions for count data are used to estimate the likelihood of having a high number of deficiencies of a specific type. The purpose is to complement existing practices focusing on detention with the objective to improve the selection process. Similar factors influence the likelihood of having a vessel detained and that of having a vessel recording a high number of deficiencies. However, quantile regressions applied to the number of deficiencies help improving the identification of factors influencing the likelihood of finding some specific types of deficiencies, which is the focus of Concentrated Inspection Campaigns. The paper concludes that the selection process for such campaigns should be improved using this new methodology.  相似文献   

Dose of truth—Monitoring marine non-indigenous species to serve legislative requirements     

《Marine Policy》2015

Non-indigenous species (NIS) are recognized as a global threat to biodiversity and monitoring their presence and impacts is considered a prerequisite for marine environmental management and sustainable development. However, monitoring for NIS seldom takes place except for a few baseline surveys. With the goal of serving the requirements of the EU Marine Strategy Framework Directive and the EU Regulation on the prevention and management of the introduction and spread of invasive alien species, the paper highlights the importance of early detection of NIS in dispersal hubs for a rapid management response, and of long-term monitoring for tracking the effects of NIS within recipient ecosystems, including coastal systems especially vulnerable to introductions. The conceptual framework also demonstrates the need for port monitoring, which should serve the above mentioned requirements but also provide the required information for implementation of the International Convention for the Control and Management of Ships Ballast Water and Sediments. Large scale monitoring of native, cryptogenic and NIS in natural and man-made habitats will collectively lead to meeting international requirements. Cost-efficient rapid assessments of target species may provide timely information for managers and policy-advisers focusing on particular NIS at particular localities, but this cannot replace long-term monitoring. To support legislative requirements, collected data should be verified and stored in a publicly accessible and routinely updated database/information system. Public involvement should be encouraged as part of monitoring programs where feasible.  相似文献