改进型经验正交函数海洋声速剖面预报方法

鉴于深海温跃层以下往往声速值缺乏,声速剖面不完整的原因,提出一种声速剖面的预报方法:在传统经验正交函数预报法基础上,首先改进协方差矩阵的求解方法,将原始数据的空间信息和时间信息有效地融合到协方差矩阵中,通过由大量实测数据统计得出的时间函数的经验公式,得到合成剖面,将二者结合,把不完整剖面垂直向下延拓到海底,较为有效地解决了传统方法求解协方差矩阵和时间函数较粗糙的问题,给出了完整的海洋声速剖面的准确预报.实测数据检验结果表明,改进方法的预报精度比传统方法有了很大提高.     

Hydrothermal plume mapping as a prospecting tool for seafloor sulfide deposits: a case study at the Zouyu-1 and Zouyu-2 hydrothermal fields in the southern Mid-Atlantic Ridge

Seafloor hydrothermal polymetallic sulfide deposits are a new type of resource, with great potential economic value and good prospect development. This paper discusses turbidity, oxidation–reduction potential, and temperature anomalies of hydrothermal plumes from the Zouyu-1 and Zouyu-2 hydrothermal fields on the southern Mid-Atlantic Ridge. We use the known location of these vent fields and plume data collected in multiple years (2009, 2011, 2013) to demonstrate how real-time plume exploration can be used to locate active vent fields, and thus associated sulfide deposits. Turbidity anomalies can be detected 10 s of km from an active source, but the location precision is no better than a few kilometers because fine-grained particles are quasi-conservative over periods of many days. Temperature and oxidation–reduction potential anomalies provide location precision of a few hundred meters. Temperature anomalies are generally weak and difficult to reliably detect, except by chance encounters of a buoyant plume. Oxidation–reduction potential is highly sensitive (nmol concentrations of reduced hydrothermal chemicals) to discharges of all temperatures and responds immediately to a plume encounter. Real-time surveys using continuous tows of turbidity and oxidation–reduction potential sensors offer the most efficient and precise surface ship exploration presently possible.     

Evaluating the relationship between spatial heterogeneity and temporal variability of larval fish assemblages in a coastal marine ecosystem (Haizhou Bay,China)

In coastal marine ecosystems, spatial patterns of larval fish assemblages (LFAs) tend to exhibit geographic stability because of relatively stable spawning site selection and predictable oceanographic phenomena such as eddies. To evaluate the relationship between spatial heterogeneity and temporal variability of LFAs, we conducted a high spatiotemporal resolution ichthyoplankton survey from April to July in 2013 in the shallow waters (<20 m) of Haizhou Bay, China. Our analysis indicated three distinct assemblages, which were stable geographically but exhibited a gradual and directional change of species composition and abundance over our study period. Sea surface temperature was the most important environmental co‐variate for determining temporal variability of LFAs, likely owing to temperature effects of species composition and spawning period selection of adult fish, along with known temperature‐dependent survival rates of larval fish. Study of LFA spatiotemporal dynamics is essential for improved understanding of adult fish spawning behavior, and has potential to inform design and implementation of conservation and management measures (e.g. marine protected areas) in coastal systems.     

Interactive Effects of Ultraviolet Radiation and Dissolved Organic Carbon on Phytoplankton Growth and Photosynthesis in Sanya Bay,Northern South China Sea

Ocean Science Journal - The effects of a simulated climate change scenario, i.e., increased ultraviolet radiation (UVR) and dissolved organic carbon (DOC), on the growth and photosynthesis of...     

Low-temperature alteration of oceanic island basalts and their contribution to transition metal circulation of the ocean

The major elements, rare earth elements （REE） and trace elements of four basalt samples from central and western Pacific ferro- manganese crust provinces have been analyzed using chemical methods and ICP - MS, respectively. The results indicate that the samples have been extensively altered and that the contents of their major elements have changed significantly. However, the similarity of REE partition patterns and trace element contents of basalt samples to those of fresh oceanic island basalts （OIB） indicate that the basalt samples originated as OIB. Because of low-temperature alteration, the contents of A1203 , Fe203 , MnO, K20 and P205 increased, while MgO and FeO decreased. Active components, such as magnesium and iron, were leached from OIB resulting in the relative enrichment of SiO2. The leaching of active components can cause the relative enrichment of REE, while the precipitation of LREE-rich ferromanganese oxides in vesicles and fissures not only causes an increase of REE contents, but also induces ＂fractionation＂ of LREE and HREE. Based on the enrichment mechanism of REE contents, the theoretical quantities of precipitated ferromanganese oxides and the depleted quantities of active components are calculated ： the depleted quantities of active components for the unit mass of fresh basalts vary in the range of 0.15 ～ 0. 657, and the precipitated quantities of ferromanganese oxides for the unit mass of fresh basahs vary in the range of 0. 006 ～ 0. 042. Of the major elements, the two most depleted are iron, and magnesium, with 18.28% ～ 70.95% of iron and 44.50% ～ 93.94% of magnesium in the fresh basalts was leached out. Theoretical calculation and geochemistry results both indicate that low-temperature alteration of basalts can supply abundant amount of metals to seawater, and may play an important role in ocean metal circulation.     

莱州湾沉积物有机质来源

应用C/N、δ13C、δ15N解析了莱州湾沉积物有机质来源,发现湾内有机质主要存在海洋、河口浮游植物以及陆地有机质3种来源。通过C/N、δ13C定量示踪,发现海洋浮游植物是湾内沉积物有机质的最主要来源,相对含量在41.6%—58.5%之间。河口浮游植物有机质、陆源有机质相对含量波动较大,分别在3.8%—43.8%、0—53.5%之间。海洋浮游植物有机质在整个海湾都表现出较高含量。近岸河口附近海域往往表现出高含量的河口浮游植物有机质特征,陆源有机质含量较高区域大都集中在黄河口周围海域,高河口浮游植物有机质以及高陆源有机质特征在黄河口周围海域均有出现。     

应用极化合成孔径雷达检测海上溢油研究进展

海上溢油给海洋生态环境带来严重的影响,快速准确地探测溢油对于防灾减灾具有重要的意义。利用卫星遥感探测溢油已成为目前主要的检测手段,大多采用合成孔径雷达(SAR)数据,运用图像处理的方法,开展了多种溢油提取算法的研究,取得了较好的结果,但由于海洋的类溢油现象存在,造成提取信息的精度达不到要求。近年来,国内外运用极化SAR数据开展溢油信息提取研究,从极化分解与相位差等角度对溢油特性分析,能有效地区分一些类溢油现象,得到了较理想的结果。分析了应用SAR数据开展溢油信息提取的研究状况,总结了溢油极化SAR探测的研究,指出了目前研究中存在的不足,并提出了今后溢油极化SAR遥感监测的方向。     

青蛤(Cyclina sinensis)TLR2基因的克隆与表达分析

利用转录组文库分析得到青蛤(Cyclina sinensis)的Toll样受体2(Toll-like receptor 2,TLR2)基因序列,采用荧光定量PCR法分析该基因的表达过程。结果显示,青蛤TLR2基因的cDNA开放阅读框为2082bp,编码693个氨基酸,具典型的LRRs、单次跨膜区和TIR结构域。该基因在血淋巴中的表达量最高,与肝脏、鳃、外套膜、闭壳肌和性腺有显著性差异(P0.05)。在鳗弧菌和Poly I:C刺激下,青蛤血淋巴中TLR2基因3h开始升高,48h达到最大值,与对照组和空白组有极显著性差异(P0.01);藤黄微球菌刺激下,血淋巴中CsTLR2基因3h开始升高,48h亦达到最大值,实验组与对照组有显著性差异(P0.05)。     

渤海莱州湾地区晚更新世以来有孔虫特征反映的古环境变化

Controlled by climate changes, there were three large-scale transgressions and regressions around the Bohai Sea during the late Quaternary, which were accepted by most geologists. However, a big controversy still exists about the time when the transgressions occurred separately. In order to find out the process of the paleoenvironmental changes around the Bohai Sea in the late Quaternary, the foraminifera assemblages from a new borehole Lz908 in the southern coast of the Laizhou Bay were studied, and then the transgressive strata were indentified. Combined with accelerator mass spectrometry radiocarbon 14C（AMS14C） and optically stimulated luminescence（OSL） ages, the occurrence time of these transgressions were re-determined. The result showed that three major large-scale transgressions occurred separately at the beginning of marine isotopic stage 7（MIS7）, the last interglacial period（MIS5） and the Holocene. In addition, a small-scale transgression occurred in the mid-MIS6, and the corresponding transgressive stratum was deposited. The transgressive deposition of MIS3 was also discovered in this study. However, the characteristics of the foraminifera indicated the environment during this period was colder than that in the MIS5. By comparison with the global sea-level changes, the paleoenvironmental changes around the Bohai Sea in the late Quaternary can be consistent with the global climate changes.     

冬季南黄海浮游动物群落结构及其对黄海暖流的指示

2009年12月和2010年1月对南黄海进行浮游动物采集, 以了解冬季浮游动物群落结构及其对黄海暖流的指示作用。结果表明, 南黄海冬季仍然以温带和暖温带种为主, 中华哲水蚤Calanus sinicus、强壮滨箭虫Aidanosagitta crassa、细足法Themisto gracilipes等温带和暖温带种类在浮游动物数量组成中具有较大优势。与此同时, 一些暖水种在调查海域局部出现。2009年12月暖水种仅分布在南黄海东南部黄海暖流源地附近。位于黄海中部的调查区东侧温盐层化现象明显, 近底层低温、高盐、高营养盐的水文特征体现了黄海冷水团的残留; 2010年1月在35°—36°N区域暖水种种类明显增加, 截平头水蚤Paracandacia truncata、长尾基齿哲水蚤Clausocalanus furcatus出现的位置与暖流路径相吻合, 海洋真刺水蚤Euchaeta rimana数量相比12月有明显向北推进的趋势。主成分分析显示暖水种的分布与温度有良好的相关性。Shannon-Weaver指数、丰富度指数、均匀度指数等没有呈现明显的分布规律, 对黄海暖流的指示作用不如种类明显。