基于20a卫星高度计数据的黑潮变异特征     

赵新华  杨俊钢  崔伟 《海洋科学》2016,40(1):132-137

黑潮作为一支典型的西边界流,其路径变化特征及其相关的物理现象对于渔业和航海有着不可忽视的影响。本文基于改进的特征线方法,利用1992~2012年的高度计绝对动力地形数据提取了整个黑潮流区逐月的黑潮主轴和边界位置,并对沿轴速度、主流宽度、表层水体输运以及路径标准差等黑潮特征量进行了分析研究。结果表明,黑潮整体的沿轴速度在夏秋季较大,最大值可达0.95 m/s,而在冬季的速度较小;黑潮主流宽度在10、11月份达到最大值;黑潮表层水体输运在夏季最大,春秋两季次之,冬季最小。沿黑潮流路分区域对黑潮特征进行分析,结果表明,越往黑潮下游,其沿轴速度、主流宽度和表层水体输运越大,同时沿轴速度和表层水体输运量最大值出现的时间也越晚,黑潮主轴位置相对于其多年平均的偏离程度越大,且随时间波动也越强烈。  相似文献   

Early Mesozoic Southward Subduction of the Eastern Mongol–Okhotsk Oceanic Plate: Evidence from Zircon U–Pb–Hf Isotopes and Whole‐rock Geochemistry of Triassic Granitic Rocks in the Mohe Area,NE China          下载免费PDF全文

Liang Li  Fengyue Sun  Bile Li  Qinglin Xu  Yajing Zhang  Ye Qian 《Resource Geology》2016,66(4):386-403

In this paper, we present new U–Pb zircon ages, Hf isotope data and major and trace elements for Early Mesozoic granitic rocks in Mohe area in the Erguna Massif of northeast China to elucidate the southward subduction of the eastern Mongol–Okhotsk Oceanic plate in Early Mesozoic. Zircons from two representative intrusions, syenogranites and monzogranites, in the Mohe area are euhedral–subhedral in shape, display oscillatory growth zoning in cathodoluminescence (CL) images, and have Th/U ratios of 0.10–0.72, and in combination these features indicating that the zircons are of igneous origin. U–Pb zircon dating results demonstrate that the syenogranites formed at 245.1 ± 1.4 Ma and monzogranites formed at 212.2 ± 1.7 Ma. These granitic rocks are characterized by high SiO₂, Al₂O₃ and (Na₂O + K₂O), low TFeO, MgO, TiO₂ and P₂O₅ concentrations, belonging to the high‐K calc‐alkaline series. They are enriched in LREE and large ion lithophile elements (e.g., Rb, K, and Sr), depleted in HREE and high field strength elements (e.g., Nb, Ta, Th, and Ti), as well as very weak negative Eu anomalies (Eu/Eu* = 0.48 ~ 1.01). Their zircon εHf(t) values range from −7.9 to −2.0 and range from 0.20 to 0.49, in response to their two‐stage Hf model ages (T_DM2) range from 1.40 Ga to 1.77 Ga range from 0.94 Ga to 1.24 Ga, respectively, indicating that primary magmas of syenogranites were derived from partial melting of newly accreted juvenile crustal material that formed from the enriched mantle during the Mesoproterozoic, monzogranites are generated by partial melting of newly accreted juvenile crustal material that formed from the depleted mantle during the Meso‐ to Neoproterozoic. We conclude, therefore, that the early Mesozoic granitic rocks of the Mohe area are associated with the continuous southward subduction of the Mongol–Okhotsk oceanic plate rather than the Paleo‐Asian and circum‐Pacific tectonic regimes.  相似文献   

渤海海洋环境状况及保护建议          下载免费PDF全文

李保磊  赵玉慧  杨琨  赵蓓 《海洋开发与管理》2016,33(10):59-62

文章分析渤海区域自然和社会经济概况,提出渤海海洋生态环境存在的问题和主要影响因素;为保障渤海海洋生态环境的可持续发展,提出实施最严格的海洋环境保护、严格控制陆源污染、集约节约利用海洋资源、实施生态环境保护修复、强化统筹协调和监督考核等保护建议。  相似文献   

上海港与宁波-舟山港港口物流竞争力比较分析          下载免费PDF全文

杨跃辉  王俊辉 《海洋开发与管理》2016,33(12):8-12

上海港与宁波-舟山港的地理区域和经济腹地相近,面临规划建设、外资引进、腹地货源、中转货源、政策资源、专业人才等各种竞争。文章通过构建港口物流竞争力综合评价指标体系,运用主成分分析法,选取港口物流营运规模、港口物流基础设施、港口物流竞争潜力3个具有代表性的指标,比较上海港与宁波-舟山港的优势与劣势,并提出相关建议。  相似文献   

中国水产品非关税贸易壁垒的实证研究——基于贸易引力模型          下载免费PDF全文

杨卫  苗青 《海洋开发与管理》2016,33(7):9-14

随着贸易自由化程度的提高以及"黄箱政策"的出台,关税壁垒在国际贸易竞争中的作用日益减弱,许多国家逐步设置以进口配额、许可证、检验检疫和技术标准等非关税壁垒为主的贸易保护措施,同时各国在政治、文化和风俗习惯等方面的差异也会对国际贸易产生一定的影响。文章以2000—2014年中国与美国、日本、韩国、加拿大和东盟的贸易面板数据为基础,在Tinbergen(1962)和Poyhonen(1963)所建立的传统贸易引力模型的基础上,对原有模型中的变量进行改进和拓展,创新提出使用军事冲突变量去量化非关税贸易壁垒对我国水产品贸易的影响,同时结合双因素方差分析方法探究贸易品种和国家区域的差异对于贸易总额的影响;结果显示,我国水产品贸易政策存在一定的调整空间,可根据不同国家背景和贸易种类在区域一体化政策、水产品生产、物流渠道建设和文化宣传方面进行政策和方法的改进。  相似文献   

国外海洋调查船发展历史和趋势以及对我国的启示          下载免费PDF全文

孟庆龙  杨维维  孙雅哲  李尉尉 《海洋开发与管理》2016,33(11):63-67

海洋调查船是专门进行海洋调查研究的工具,涉及船舶设计、建造、海洋调查技术、航海管理和海洋调查实验管理等领域,是我国海洋强国战略和"一带一路"战略构想顺利实施的重要保障。文章梳理欧美自大航海时代以来海洋调查船的发展历程,选取各时期具有代表性的船舶,总结其特点和最新发展趋势,以期为我国海洋调查船的设计建造思路提供启示。  相似文献   

深海采矿转臂机构采矿姿态优化研究     

周知进  杨智  罗柏文 《海洋工程》2016,34(1):88-93

针对海底地形不平坦特性,提出了一种变幅机构来自适应海底地形采矿姿态的采矿机构。综合考虑采矿机构采掘头距海底高度对采矿率影响,利用关键点法建立了节臂上的点到海底地形距离的数学模型。在此基础上,建立了以采矿率最高为目标的最优采矿姿态数学模型。以某实际地形为例,采用模拟退火遗传算法优化求解最优采矿姿态。根据其优化后结果可知,其最优采矿姿态与海底地形坡度变化一致,从而证明了采矿姿态模型的正确性。  相似文献   

青藏高原东北部降尘通量及粒度特征分析          下载免费PDF全文

鄂崇毅  席永帅  孙永娟  赵亚娟  杨龙  吕顺昌 《盐湖研究》2016,24(2):62-67, 74

青藏高原东北缘是柴达木沙尘暴东移的必经之道和沉降区,对青藏高原东北部降尘时空分异特征进行分析,有助于认识青藏高原区域粉尘输送的现代过程和机制。2013年12月至2015年5月分别在青海湖小泊湖(XBH)、西宁多巴(DB)、西宁青海师大科技楼顶(KJLD)设置降尘缸,进行湿法收集。对其降尘通量和粒度特征进行了时空分异特征分析,结果显示,1)西宁地区2014年降尘通量为442~542 g/m~2·a,青海湖XBH采集点指示的2014年降尘通量为415 g/m~2·a,降尘通量年际变化较大,各站点降尘通量季节变化趋势一致,降尘主要集中在冬春季,夏季降尘通量最低;2)各站点降尘粒度组成特征非常相似,以粉砂为主(4~63μm),西宁地区尘暴与非尘暴降尘粒度频率曲线呈近似正态分布,尘暴期间降尘粒径较非尘暴时段大;3)XBH、DB和KJLD 3点所有样品平均粒径分别为37μm、34μm和31μm,中值粒径分别为31μm、27μm和26μm;对比低海拔兰州尘暴粒径特征,发现降尘粒径存在一定的海拔依赖性,即粒度随海拔增高逐渐变粗。  相似文献   

Size distributions and source function of sea spray aerosol over the South China Sea     

CHU Yingjia  SHENG Lifang  LIU Qian  ZHAO Dongliang  JIA Nan  KONG Yawen 《中国海洋大学学报(英文版)》2016,15(4):569-576

The number concentrations in the radius range of 0.06 – 5 μm of aerosol particles and meteorological parameters were measured on board during a cruise in the South China Sea from August 25 to October 12, 2012. Effective fluxes in the reference height of 10 m were estimated by steady state dry deposition method based on the observed data, and the influences of different air masses on flux were discussed in this paper. The number size distribution was characterized by a bimodal mode, with the average total number concentration of(1.50 ± 0.76)×10~3 cm~(-3). The two mode radii were 0.099 μm and 0.886 μm, both of which were within the scope of accumulation mode. A typical daily average size distribution was compared with that measured in the Bay of Bengal. In the whole radius range, the number concentrations were in agreement with each other; the modes were more distinct in this study than that abtained in the Bay of Bengal. The size distribution of the fluxes was fitted with the sum of log-normal and power-law distribution. The impact of different air masses was mainly on flux magnitude, rather than the shape of spectral distribution. A semiempirical source function that is applicable in the radius range of 0.06 μmr_(80)0.3 μm with the wind speed varying from 1.00 m s~(-1) to 10.00 m s~(-1) was derived.  相似文献   

潍坊市国土资源综合监管平台设计与实现          下载免费PDF全文

杨先连 《山东国土资源》2016,32(8)

运用地理信息技术、信息技术等现代化科技手段,以潍坊市国土资源"一张图"数据中心为数据基础,实现地理空间数据与国土应用数据整合,有效掌控已有资源,建立信息采集、综合查询、综合分析、批后跟踪、预警评价、辅助决策、辅助业务办理等功能为一体的国土资源综合监管平台,以科技手段实时监管监控土地"批、供、用、补、查"动态。  相似文献