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51.
山东近海牙鲆(Paralichthys olivaceus)自然和养殖群体10个微卫星基因座位的遗传多态性分析 总被引:26,自引:7,他引:26
采用微卫星遗传标记技术对山东近海牙鲆自然群体和养殖群体的遗传多样性进行了研究。实验所用牙鲆于2003年5月分别采自山东近海和青岛胶南养鱼场,各20尾,取全血或肌肉组织,以酚-仿抽提方法提取基因组DNA,利用筛选获得的10对微卫星引物进行PCR扩增,反应产物经8%非变性聚丙烯酰胺凝胶电泳分离、EB显色,用ImageMasterl D Elite(Version 3.01)软件分析电泳结果,并计算了相应的遗传学参数。结果表明,在自然和养殖群体中,10个基因座位的等位基因平均数(α)分别为6.7和6.1,每个基因座位有效等位基因数(αe)分别为1.8—6.8和2.5—6.7,群体平均杂合度(H)分别为0.8120和0.7310;两个群体间的遗传相似性系数、遗传距离和基因分化系数为0.8558、0.1557和0.0558;自然群体内每个座位上的多态信息含量(PIC)为0.59—0.84、个体识别率(DP)为0.54—0.86、非父排除率(PPE)为0.41—0.72,其累积个体识别率和非父排除率均达到0.9999,表明所选座位属中高识别力的遗传标记,可以将它们应用于今后牙鲆雌核发育群体的遗传变异分析以及进一步的遗传育种的研究中。 相似文献
52.
Toru?Iwata Keiko?Yoshikawa Katsutoshi?Nishimura Yoshihisa?Higuchi Takao?Yamashita Shigeru?Kato Eiji?OhtakiEmail author 《Journal of Oceanography》2004,60(6):995-1000
The measurements of the vertical transport of CO2 were carried out over the Sea of Japan using the specially designed pier of Kyoto University on September 20 to 22, 2000. CO2 fluxes were measured by the eddy correlation and aerodynamic techniques. Both techniques showed comparable CO2 fluxes during sea breeze conditions: −0.001 to −0.08 mg m−2s−1 with the mean of −0.05 mg m−2s−1. This means that the measuring site satisfies the fetch requirement for meteorological observations under sea breeze conditions. Moreover, the eddy diffusivity coefficient used in the aerodynamic technique is found to be consistent with the coefficient used in the eddy correlation technique. The present result leads us to conclude that the aerodynamic technique may be applicable to underway CO2 flux measurements over the ocean and may be used in place of the bulk technique. The important point is the need to maintain a measuring accuracy of CO2 concentration difference of the order of 0.1 ppmv on the research vessels or the buoys. 相似文献
53.
54.
鲽形目3亚目8科51属142种。鲀形目2亚目9科57属143种。海蛾鱼目1科2属3种,鮟鱇目3亚目11科23属41种。 相似文献
55.
Photoinduced toxicity single and binary mixtures of four polycyclic aromatic hydrocarbons to the marine diatom Skeletonema costatum 总被引:1,自引:0,他引:1
Diatom Skeletonema costatum Cleve is one of the main predominant phytoplankton species in the Changjiang Estuary in China. In order to provide some basic information for future assessment of the potential risk on phytoplankton communities in this estuary caused by polycyclic aromatic hydrocarbons(PAHs), this alga was selected as a representative to investigate the photoinduced toxicity of PAHs, in single and mixture. Four PAHs including three-ring phenanthrene and anthracene, four-ring fluoranthene and pyrene were tested in the laboratory. The single toxicity of each PAH on this microalga was compared with and without the simulated solar UV radiation. The results showed that this microalga was sensitive to PAH's photoinduced toxicity. Ratios of the 72 h median effect concentration obtained for fluorescent and UV light tests were about 8.4 for phenanthrene, 13.0 for anthracene, 6.5 for fluoranthene, and 5.7 for pyrene, indicating that UV light enhanced the PAH toxicity to this alga significantly. Under the fluorescent radiation (lacking UV), the dose-response curves based on chemical concentrations revealed that the order of toxic strength was fluoranthene greater than pyrene greater than anthracene greater than phenanthrene; while under the UV radiation (476 μW/cm2 for UVA, 6.5 μW/cm2 for UVB) it became fluoranthene approximately equaling anthracene greater than pyrene greater than phenanthrene, indicating that the UV light also changed its relative toxicity to this alga. The photoinduced toxicity of PAHs to the marine diatom S. costatum might be a synergistic effect of photosensitization reactions (e.g., generation of single-state oxygen) and photomodification (photooxidation and/or photolysis).The combined effects of six binary mixtures on the marine diatom S. costatum were investigated using the additive-index method. Four binary-mixtures (phenanthrene plus anthracene; phenanthrene plus pyrene; anthracene plus fluoranthene; anthracene plus pyrene) were found to be synergistic joint action mode, while two binary-mixtures (phenanthrene plus fluoranthene; fluoranthene plus pyrene) displayed antagonist, revealing a complex pattern of possible interactions. The combined action mode of PAHs might be related to various factors such as the mixture compounds, mixture ratios and test conditions, etc. 相似文献
56.
Mohamed?IsmailEmail author Tadashi?Kimura Yumiko?Suzuki Makoto?Tsuchiya 《Journal of Oceanography》2005,61(3):631-644
Total mass flux, size distribution of sediment particles and some chemical components such as total carbon (TC), total nitrogen (TN) and calcium carbonate (CaCO3) were monitored monthly using a multi-cup sediment traps at seven coral reef sites (6 reef flat and 1 reef slope) of the Marine Protected Areas around Ishigaki, Kohama, Kuroshima and Iriomote Islands in the southern Ryukyus, Japan from September 2000 to September 2001. The size distribution of trapped sediments revealed mostly uni-modal fine sand to mud in the reef flat and gravelly to coarse sand in the reef slope. The total mass flux ranged between 0.54 to 872 gm−2d−1, and showed a pronounced seasonality (high in summer-autumn and low in spring) at each site, which was consistent with the rainfall and typhoon regime. Exceptionally high values were observed on the reef slope (Iriomote) in February–March 2001 (1533 gm−2d−1) owing to a large amount of bottom sediment re-suspension. On the reef flat (Todoroki South and North; Ishigaki), values obtained in July–August 2001 (872 gm−2d−1) and August–September 2001 (800 gm− 2d−1) indicate the high terrestrial discharge from Todoroki River. Trapped sediment particles consist of CaCO3 (1.2–27.1%) and a non-carbonate fraction (98.8–72.9%), which contains total carbon (4.9–26%), carbonate carbon (CO2-C) (0.2–3.1%) and non-carbonate carbon (NC-C) (7.9–25.6%). Total nitrogen content was in the range 0.02–0.48%. TN is contained mainly in the carbonate fraction and NC-C may be contained in the non-carbonate fraction. The low TN/OC ratio of the trapped sediments suggests that they were mostly of terrestrial origin and that both fractions migrated. The high total mass flux derived from Todoroki River exceeded the threshold at which a lethal effect on coral community is caused. The results stress the importance of conducting seasonal studies of sedimentation over more than one year and at more than one location in south Japan coral reef ecosystems to gain an understanding of the processes controlling the total mass fluxes and their nutrients content, also to develop an awareness of how to prevent the damage of coral reef ecosystems and, if it does occur, to allow mitigation measures to be undertaken. 相似文献
57.
Using 203HgCl2 as a tracer, uptake and combination of inorganic mercury in Tilapia mossambica (petres) and its transfer between different tissues of the fish were studied. The results demonstrate that gill is the main tissue uptaking mercury directly from seawater and that the mercury in gill, skin, digestive tube and fin would be transferred to the other tissues. The result of gel chromatography with Sephadex G-75 shows that most of mercury in gill filaments, liver, and digestive tube are bound in high molecules (MW-70000) and not in metallothionein, but in kidney and bile mercury binding proteins are similar to metallothionein and are accounted for up to 60% and 46% respectively. 相似文献
58.
Riccardo?Geletti Emanuele?LodoloEmail author Anatoly?A.?Schreider Alina?Polonia 《Marine Geophysical Researches》2005,26(1):17-28
The structural framework of the southern part of the Shackleton Fracture Zone has been investigated through the analysis of
a 130-km-long multichannel seismic reflection profile acquired orthogonally to the fracture zone near 60° S. The Shackleton
Fracture Zone is a 800-km-long, mostly rectilinear and pronounced bathymetric lineation joining the westernmost South Scotia
Ridge to southern South America south of Cape Horn, separating the western Scotia Sea plate from the Antarctic plate. Conventional
processing applied to the seismic data outlines the main structures of the Shackleton Fracture Zone, but only the use of enhanced
techniques, such as accurate velocity analyses and pre-stack depth migration, provides a good definition of the acoustic basement
and the architecture of the sedimentary sequences. In particular, a strong and mostly continuous reflector found at about
8.0 s two-way traveltime is very clear across the entire section and is interpreted as the Moho discontinuity. Data show a
complex system of troughs developed along the eastern flank of the crustal ridge, containing tilted and rotated blocks, and
the presence of a prominent listric normal fault developed within the oceanic crust. Positive flower structures developed
within the oceanic basement indicate strike-slip tectonism and partial reactivation of pre-existing faults. Present-day tectonic
activity is found mostly in correspondence to the relief, whereas fault-induced deformation is negligible across the entire
trough system. This indicates that the E–W-directed stress regime present in the Drake Passage region is mainly dissipated
along a narrow zone within the Shackleton Ridge axis. A reappraisal of all available magnetic anomaly identifications in the
western Scotia Sea and in the former Phoenix plate, in conjunction with new magnetic profiles acquired to the east of the
Shackleton Fracture Zone off the Tierra del Fuego continental margin, has allowed us to propose a simple reconstruction of
Shackleton Fracture Zone development in the general context of the Drake Passage opening. 相似文献
59.
60.
The large-diameter cylinder structure, which is made of large successive bottomless cylinders placed on foundation bed or partly driven into soil, is a recently developed retaining structure in China. It can be used in port, coastal and off-shore works. The method for stability analysis of the large-diameter cylinder structure, especially for stability analysis of the embedded large-diameter cylinder structure, is an important issue. In this paper, an idea is presented that is, em-bedded large-diameter cylinder quays can be divided into two types, i.e. the gravity wall type and the cylinder pile wall type. A method for stability analysis of the large-diameter cylinder quay of the cylinder pile wall type is developed and a method for stability analysis of the large-diameter cylinder quay of the gravity wall type is also proposed. The effect of sig-nificant parameters on the stability of the large-diameter cylinder quay of the cylinder pile wall type is investigated through numerical calculation. 相似文献