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991.
雷州半岛海洋文化与海洋经济发展关系研究   总被引:2,自引:0,他引:2  
李巧玲 《热带地理》2003,23(2):149-153
追溯雷州半岛海洋文化历史渊源,对其海洋文化与海洋经济进行定位,认为传承雷州半岛海洋文化,发展特色海洋产业是该区域海洋经济成功的关键.为此宜采取以下对策:重塑"南珠故乡"形象,发展海水养殖及加工业;重塑"海上丝路始发港 "形象,发展港口运输贸易业;树"大陆最南端,椰风海韵文化游"形象,发展滨海旅游业.  相似文献   
992.
广东作为我国第一海洋经济大省,重点布局了海洋电子信息等海洋六大产业,目标打造2~3个产值千亿元级产业集群。文章以欧洲107个海洋创新型产业集群为研究对象,梳理其海洋产业前沿交叉领域布局,分析产业集群空间分布特征,探讨产业集群的先进组织管理模式。结果表明,欧洲海洋创新型产业集群以可持续蓝色增长为发展主线,空间分布均衡且实行错位分工协同发展,通过系统建立大量产业集群促进机构和监管体系,构建国际战略集群伙伴关系,引导集群的良性发展。在此基础上,从合作对象、组织机构、交流合作、资金激励和监管体系等角度提出了广东培育海洋创新型产业集群相关建议。  相似文献   
993.
江苏南部滆湖成因演化的初步认识   总被引:4,自引:0,他引:4  
赵为民  李端璐 《江苏地质》2006,30(2):106-111
借助高速公路勘察资料及前人研究成果,分析了江苏南部滆湖地区第四纪晚更新世土层空间的展布特征。据此认为,晚更新世晚期在常州西存在北东走向的古长江汊流河谷,滆湖是连接该河谷的古河道所在地。湖区钻探水下发现宽达300m的北东走向全新世古河道,进一步说明河道淤塞是形成现今滆湖的主要成因。  相似文献   
994.
通过对安达曼海重力柱ADM-C1的浮游有孔虫群落分析, 探讨了该区全新世以来的海洋环境演化。研究发现, 该区浮游有孔虫群落总体以热带暖水种Globigerinoides ruber、Globigerinoides sacculifer、Neogloboquadrina dutertreiPulleniatina obliquiloculata等为主。其中G. ruber的相对丰度从早全新世至今呈逐渐降低的趋势, G. sacculifer则呈大致相反的变化趋势。N. dutertrei的相对丰度从11—7.9ka BP较高, 到7.9—3.8ka BP偏低, 3.8ka BP以来又逐渐升高。而P. obliquiloculata的变化趋势则与N. dutertrei大致相反。研究认为, 安达曼海不存在与冲绳海槽类似的晚全新世普林虫低值事件。浮游有孔虫群落Q型因子显示全新世海洋环境呈现三个明显的阶段变化: 早全新世 11—7.9ka BP期间, 浮游有孔虫群落以G. ruber、N. dutertreiG. bulloides为主, 反映了该阶段较强的夏季风降水会导致表层水体盐度较低, 同时冬季风的影响相对较强; 7.9—3.8ka BP期间, 以G. ruber、P. obliquiloculataGlobigerinella aequilateralis为主, 指示水体盐度仍然较低, 同时次表层属种显著增多, 对应了该阶段强盛的印度夏季风, 上层海水混合强烈; 3.8—0ka BP期间, 以G. sacculifer、N. dutertreiP. obliquiloculata为主要特征属种, 而G. ruber相对丰度明显下降, 表明该时期表层海水的盐度有显著上升, 对应了印度夏季风降水的明显减弱。安达曼海浮游有孔虫群落所呈现的全新世海洋环境阶段性变化和陆地夏季风记录有很好的一致性, 也与该孔敏感粒级组分所反映的印度季风的强度变化一致, 表明热带边缘海区的有孔虫群落组合可以很好地响应区域海洋环境变化。  相似文献   
995.
Abstract. In the water-column of the Gulf of Trieste (Northern Adriatic Sea) flocculent, amorphous aggregates known as marine snow reach maximum density and dimensions up to 20cm in diameter during summer months. Sampling of these fragile macro-aggregates was carried out by SCUBA-divers.
A large detrital component was found to be embedded in an organic matrix together with a large array of intact phytoplankton species. Heterotrophic bacterial density ranged from 2–65 × 108 cells-g-1 (marine snow dry wt) and is therefore of the same order of magnitude as in the surface layer of the sediments of the Gulf. In terms of biomass, bacteria reached only 30–95% of heterotrophic microflagellates.
A mean abundance of marine snow of 5g (marine snow dry wt) m-3 was obtained for the water-column above the pyenolinc. At this boundary layer, however, a mean abundance of about 10g (marine snow dry wt) m-3 led to the formation of a distinct, 10-50cm thick layer. Based on these data and sedimentation rates of marine snow to the pyenoclinc (38 g [marine snow dry wt] m-2 d-1) the potential ecological significance of these macro-aggregates for the pelagic system of the Gulf of Trieste is discussed.  相似文献   
996.
997.
Abstract

Sands and silty sands are the predominant surficial soils of continental shelves. Cohesive fine‐grained soils are typical off the mouths of large rivers, near bays and estuaries, and in basins located on the shelf. The stratigraphy of shelf soils is very poorly known for most engineering purposes, except in the vicinity of the Mississippi Delta.

Vibratory coring is the most common method of sampling shelf sands to depths of about 13 m; greater soil depths are sampled by borings often using drilling and wireline sampling tools. Employment of self‐contained or wireline static cone penetrometers to obtain in situ measurements of sands has not been as common in the United States as in Europe. Dynamic piston corers are the most common samplers in cohesive soils, but rotary and hydraulically activated incremental corers are becoming available for marine use. Self‐contained or wireline vane shear devices and static cone penetrometers are used for the in situ testing of cohesive soils, and the latter device is also used for cohesionless soils. Dynamic cone penetrometers have been developed and have had limited experimental use at sea. In situ electrical resistivity and nuclear‐transmission and backscatter probes have been used in cohesive soils to obtain bulk‐density and water‐content measurements and for stratigraphic correlation. Acoustical properties of cohesive and cohesionless soils have been measured by in situ probes and have been estimated from results of geophysical surveys made on ships that are under way.

Environmental hazards to the foundations of offshore structures include earthquakes, wave‐induced loading and scour, and burrowing animals. Reported bottom‐current velocities on the United States continental shelf appear to have maximums of about 0.5 m/s under fair‐weather conditions and greater than about 5 m/s under hurricane conditions. Cyclical loading of the seafloor induced by storm waves appears to be a major hazard to soil stability in some areas.

A representative sample of the widely scattered engineering and scientific literature of continental shelf marine geotechnics and geotechnically related subjects has been made to aid marine geologists, geotechnologists, and other specialists.  相似文献   
998.
In this paper, we develop the triangle of marine governance to understand the changing locus and focus of marine governance practices. In general, the locus and focus of marine governance is shifting from top-down, state-led governance to network governance. This shift is captured by the triangle of marine governance, because the triangle refers to the institutional setting in which politics and policy making takes place (polity), to policy making itself (policy), to activities of politicians and processes of power (politics), and to the interplay between policy, politics and polity. Studying the dynamics of politics and policies in marine governance practices through the triangle allows us to analyze and explain how and why the shifts in locus and focus occur. These dynamics of marine governance—as the interplay of policy, politics and policy—is illustrated by the environmental governance of Dutch offshore platforms.  相似文献   
999.
A multi‐disciplinary approach was followed to investigate two thick palaeosol strata that alternate with wind‐blown dominated deposits developed along the Alghero coast (North‐west Sardinia, Italy). Optically stimulated luminescence ages reveal that both palaeosols were developed during cooler drier periods: the first one at around 70 ka Marine Isotope Stage 4 and the latter around 50 ka (Marine Isotope Stage 3). In contrast, the pedological features indicate that the palaeosols underwent heavy weathering processes under warm humid to sub‐humid conditions, characteristic of the Sardinian climate during the last interglacial stage (Marine Isotope Stage 5e). To reconcile this apparent data discrepancy, a range of sedimentological and pedological analyses were conducted. These analyses reveal that the palaeosols possess a complex history, with accumulation and weathering occurring during Marine Isotope Stage 5e, and erosion, colluviation and final deposition taking place during the following cold stages. Thus, even if these reddish palaeosols were last formed during the glacial period, the sediments building up these strata probably record the climate of the last interglacial stage (Marine Isotope Stage 5e). Trace element and X‐ray diffraction analyses, together with scanning electron microscope images, reveal the presence of Saharan dust in the parent material of the palaeosols. However, no evidence of any far‐travelled African dust has been observed in the Marine Isotope Stage 4–3 aeolian deposits. It is possible to conclude that in the West Mediterranean islands, Saharan dust input, even if of modest magnitude, is preserved preferentially in soils accumulated and weathered during interglacial stages.  相似文献   
1000.
Borehole and surface outcrop data are used to construct sub-Chalk, sub-Upper Chalk and sub-Tertiary contour maps for the Chiltern area. The results show a southwest-northeast monocline, which coincides with the change of slope at the lower boundary of the morphological bench on the Chalk dipslope that Wooldridge and Linton attributed to Plio-Pleistocene marine erosion. Younger northwest-southeast synclines coincide with the main transverse river valleys of the Chilterns. The monoclinal flexuring casts doubt on the value of the bench as evidence for a Plio-Pleistocene transgression.  相似文献   
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