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The surface cold and warm tongues are used as a key characteristic to describe the spatial feature of SST. However, that characteristic is often used qualitatively rather than quantitatively because of lacking quantitative parameters. In this paper, we use nine years (2006-2014) merged microwave and infrared SST data to analyze quantitatively the spatial and temporal variations of the surface cold and warm tongues in the Bohai, Yellow and East China Seas (BYES). The characteristics of the surface cold and warm tongues are expressed in terms of their path and associated temperature. Two cold tongues and six warm tongues are identified in the BYES in February. The Empirical Orthogonal Function (EOF) analysis shows that the total variance of the path of tongues is explained mostly by the three leading EOF modes (73.4%). Specifically, the first spatial mode of path shows that every tongue moves coherently in same direction, and the most significant movement occurs in the central and the west of East China Sea. In contrast, the second and third spatial modes show that most tongues move with a seesaw pattern, and the most significant movement occurs at the south of Kyushu and in the Yellow Sea respectively. The total variance of temperature on the path of tongues is explained mostly by the first EOF mode (69.6%),which has a coherent increase or decrease of temperature in each tongue with a large amplitude in the Bohai and Yellow Seas. Both the path and associated temperature of the tongues have a 2-3 year inter-annual variation, however only the second EOF temporal mode of the path has passed the significant test. In winter, the relatively even loss of the heat in the sea leads to a much faster decrease of SST in the shallow area than in the deep area and forms cold and warm patterns associated with the bathymetry of the BYES. The uneven advectional heat transport plays a different role at various areas to reinforce and compensate the decrease of SST. In the cold tongue area, the advectional heat transport reinforces the heat loss of the water and leads to a much colder SST than the surrounding area, consequently forms the cold tongues. In contrast, in the warm tongue areas, the advectional heat transport compensates the heat loss of the water and leads to a much warmer SST than the surrounding area, consequently forms the warm tongues. The advectional heat transport plays a major role at the formation of the cold and warm tongues in the BYES.

Thorpe scale and turbulent diffusivities in Prydz Bay of Antarctica were calculated based on Thorpe method and Conductivity-Temperature-Depth data. The strength of turbulent overturn was analyzed and its spatial distribution was also investigated. The results show that the larger Thorpe scale and turbulent diffusivities occur in rough topographic area and near the sea floor, and the maximum value of turbulent diffusivities exceeds 10^-2 m²/s, which is about two or three orders of magnitude larger than that in the open ocean. Turbulent diffusivities and dissipation rate of turbulent kinetic energy show high-low-high vertical structure in some observational stations, especially in deep area. The larger values of buoyancy frequency appear in upper 500 m water column in deep area, but this phenomenon is not obvious in shallow area. The dissipation rates of turbulent kinetic energy in the stations around the point(67.25°S,73°E) and along the 78°E sections are quite large, which exceed 10^-6 w/kg, and even reach 10^-5 w/kg in a few stations.

The operation of Three Gorges Reservoir causes the variation of runoff in the middle and lower reaches of the Yangtze River, inevitably resulting in the changes in tidal dynamics. Based on the data of river discharge and tidal level in recent 20 years, the response of hydrodynamics in tidal reach of the Yangtze River to variation in runoff was investigated by statistical analysis and tidal harmonic analysis. The results show that the operation of Three Gorges Reservoir causes the significant change in interannual distribution of runoff, with river discharge increase by more than 20% percent in discharging period and decease during storage period. Besides, in river reach between Datong and Jiangyin, the tidal level with guarantee ratio of 10%~70% is significantly decreased, but the tidal level with guarantee ratio of 80%~100% is slightly increased. Furthermore, the tidal range and amplitude of M₂ tidal constitute is decreased during discharging period, indicating a decrease in tidal dynamics, while the tidal range and amplitude of M₂ tidal constitute is increased during storage period, indicating a increase in tidal dynamics.

The evolution of tidal bore in Qiantang Estuary were successfully reproduced by applying FVCOM model through improving the sea bed roughness coefficient and setting suitable background vertical eddy viscosity. Sea bed roughness coefficient,calculated using the Manning formulation, is between 0.000 2~0.002 9 with the varying depth. The background vertical eddy viscosity is 1×10^-4 m²/s. The simulation well reproduces the tidal bore arriving time, tidal level, setup height, horizontal velocity magnitude and vertical profile, which implies the choice of parameters such as the bed roughness coefficient and background vertical eddy viscosity are reasonable. The procedure could be extended to simulate the 3D tidal movement for tidal bores.

High Frequency Surface Wave Radar(HFSWR) with small circular array was deployed in Zhujiajian and Shengshan to detect the winds, waves, and currents in the overlapping area in 2007. No. 1509 Typhoon Chan-hom landed in the coastal areas of Jujiajian, and then moved north by east, passing the HFSWR detection area. The HFSWR inversed results were compared to anchored buoy observed data and the large area wind data from ASCAT satellite remote sensing respectively. The results of comparison indicate that HFSWR data basically reflect the real distribution of wind and current at Zhoushan area during Typhoon Chan-hom, showing the HFSWR's applicability in detecting the winds and currents under high sea state conditions.

The contents and distribution of glycerol dialkyl glycerol tetraethers (GDGTs) were analyzed for ten surface sediments from Prydz Bay of Antarctic. The results show that the contents of GDGTs are 27.69~900.78 ng/g with the isoprenoid GDGTs accounts for 94% ~99%, much more higher than branched GDGTs. Isoprenoid and branched GDGTs have same distribution tendency that the highest content area appears in southeast while the lowest area appears in northwest direction. Isoprenoid GDGTs and branched GDGTs both have obvious positive correlation with TOC. Analysis shows that isoprenoid GDGTs comes from marine Archaea, while branched GDGTs derives from bacteria in sediments. Compared with the WOA database, the TEX₈₆ and TEX^L₈₆ derived temperatures are consistent with the sea surface temperatures in January in the study area. This study means TEX₈₆ and TEX^L₈₆ indexes could be applied to reconstruct the paleotemperature in Prydz Bay.

12 surface sediment samples from the western region of CC Zone of the East Pacific Ocean were taken as the research material, and the particle size, chemical composition and mineral composition were analyzed to discuss its sedimentary environment and material source. The study area is located in the deep ocean, and the sediment is mainly composed of the abyssal clay and silicon calcareous clay. It contains a small amount of siliceous clay, clayey siliceous ooze and clayey calcareous ooze. Clay mineral composition is mainly smectite and illite, containing part of the kaolinite and chlorite. Clay minerals indicate that the sediments in the area are mainly terrigenous,which are carried by high airflow. The Antarctic Bottom Water and hydrothermal activity have a certain influence on the source of the provenance. The geochemical characteristics of sediments also indicate that the sediments are mainly derived from terrestrial sources. The distribution curve of the REE is similar to that in the surface water of the North Pacific Ocean, and it shows strong Ce losses, indicating that the bio-deposition caused by biological activities also has a certain impact on the surface sediments.

The extracellular polymeric substance (EPS) was secreted when marine benthic diatom attached on submerged surfaces, the environment factors had a directly impact on the composition and secretion action of EPS. The effects of the oxygen content and the attachment area on EPS were studied. The EPS from marine benthic diatoms were extracted by hot solvent method. The phenol-sulfuric acid method was employed to measure the content of polysaccharide and the Coomassie Brilliant Blue G-250 method was employed to measure the content of protein in the extractions. The cell number of diatoms was measured through the method of blood cell counting plate and UV spectrophotometry. The results show that the growth rate of diatoms is fast and the secretion amounts of EPS in a single cell are great under the higher oxygen content and larger attachment area conditions. The oxygen content has a great impact on the content of water-soluble polysaccharide as the main composition in EPS, while it has little impact on the else components. Compared to the oxygen content, the attachment area has little impact on the attachment and growth of diatoms.

In order to reasonably develop, utilize and protect islands' resources in Liaoning Province and optimize the industry structures and arrangements on islands, the spatial distribution characteristics of islands in Liaoning Province were investigated by application of GIS spatial analysis, Lorenz Curve and Gini Coefficient calculation based on the statistical data of 633 islands'coordinates and land areas, which have been listed in the Standard Directory of Islands in China Sea .The results show that the distribution type of islands in Liaoning Province belongs to aggregated distribution and presents group and zonal distribution in space. The islands of Liaoning Province have shaped Changshan Island aggregation district in the northern of the Yellow Sea and shallow sea aggregation zones in the southern of Liaoning Peninsula and in the western of Liaodong Gulf in terms of the levels of aggregation. Approximately 60% islands locate within the range of 10 km off the mainland coastline in straight line, leading to near the land at high degree. The land areas are imbalance among islands with the Gini Coefficient of 0.9.

Aiming at the practical demand of deep ocean mining, the hydraulic station on the nodule collector was proposed to separate from the nodule collector and hydraulic station was designed as a floating body, relatively independent and suspended above the front of the nodule collector. Contour of floating body for polymetallic nodule concept vehicle (referred to as floating body) was designed, and its 3D model was established adopting SolidWorks. The hydrodynamic and computational model of the floating body was established, after simplifying the 3D model. Reynolds average navier-stokes algorithm (RANS algorithm) and turbulence model were applied, and drag data under the condition of different working conditions was obtained adopting fluid dynamics simulation and analysis software ANSYS CFX. Drag characteristic of floating body was studied adopting curve fitting function of Matlab, and the feasibility of contour design was verified.

To elucidate the composition and structure of macrobenthic communities and their inter-annual variations in the Yellow Sea and the Bohai Sea, Agassiz trawling was conducted in May 2010 and June 2013. The composition and structure of macrobenthic communities in the Yellow Sea and the Bohai Sea were revealed and analyzed, including species composition, dominant species, abundance, biomass and community structure, and AMBI and m-AMBI were also used to assess the ecological status. The results showed as follows: A total of 131 macrobenthic species were identified, with Mollusca (51 species) and Crustacea (42 species) as the dominant groups in these waters, followed by fishes, polychaetes and echinoderms. There were four species whose dominance were over 0.02, including Alpheus japonicus, Crangon hakodatei, Stegophiura sladeni and Acila mirabilis, of which Stegophiura sladeni had the highest abundance and dominance. The results of benthic biological indices (AMBI and m-AMBI) showed that the benthic ecological status in the Yellow Sea and Bohai Sea was relatively stable, however, the benthic ecological quality had degraded during the last few decades when compared with historical data and published researches.