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The water exchange and its spatial and temporal variation in the Xiangshangang Bay were studied with an advection-diffusion water exchange numerical model. The model is based on the well-verified three-dimensional baroclinic model for hydrodynamic process and dissolved conservative material was used as the tracer. The initial tracer concentration was set to 1 mg/L inside the bay and 0 mg/L outside the bay and at the open boundaries inflow. According to the tracer concentration, half-life time and mean residence time of the water mass at different points of the bay were calculated, and the contribution of baroclinic power to the water exchange was studied by comparison with that at barotropic model. The results show that the water exchange, to the east of the Xize section, is fast with a half-life time of 5 days and a mean residence time of about 15 days. While the half-life time and mean residence time to the east of the Xihugang inlet are 15~20 days and 25 days separately. And the section near the Wusha Mountain has a half-life time of about 25 days and a mean residence time of about 30 days. Moreover, water exchange in the top of the bay is even slower, with a half-life time of 30~ 35 days and a mean residence time of 35~ 40 days in Tiegang harbor and Huangdungang harbor. The result shows that, both the half-life time and mean residence time increase gradually from the mouth to the top of the Xiangshangang Bay, suggesting the water exchange rate and governing mechanism differ spatially in the Bay. The region between the mouth of the bay and Xize is an area of strong tidal current, where the water flows out with the ebb current and mixes with the water outside, then flows back into the bay with flood current. So the exchange rate here is quite high, and the water closer to the mouth is mixed more fully. However, the inner part of the Xiangshangang Bay is dominated by gravitational circulation and tidal oscillation, where the mixing is much weaker and the period of water exchange is much longer than that in the outer part of the bay. The comparison of the water exchange in barotropic model with that in baroclinic model shows that the baroclinic hydrodynamic power has; considerable influence on the water exchange process inside the Xiangshangang Bay, and that the gravitational circulation and water stratification increase obviously the exchange rate, while, it has little effect on the outside part of the bay where it is controlled by advection and tidal diffusion.

Taking the year of 2000 as an example, the ocean waves in the sea adjacent to Zhejiang were simulated using SWAN model, and the wave power was calculated. Firstly, average annual and monthly wave power distributions were analyzed. The results show that the wave power is about 2~6 kW·m^-1 in the sea adjacent to Zhejiang,and increases seaward. Due to the effect of monsoon its seasonal variation is obvious far from the coast while it is not so obvious near the coast. Secondly, through analysis of wave joint distribution of wave height and period which corresponds respectively to wave occurrence frequency and wave power, we compare the wave power joint distribution of wave height and period in the sea area of northern,middle and southern Zhejiang. A parameter of ‘wave power ratio’ was introduced, which represents the proportion of cumulated wave power during one year within a range of wave height and period. Generally, the wave height and period range of big‘ wave power ratio’ and high wave occurrence frequency is very close but not completely the same. The range of big ‘wave power ratio’ and high wave occurrence frequency are relatively close in the sea area of northern Zhejiang,but the corresponding mean wave power is comparatively low, while the corresponding mean wave power of the rang of big ‘wave power ratio’ in the sea area of southern Zhejiang is high, but a little bit different from the range of high wave occurrence frequency. The situation in the sea area of middle Zhejiang is in between that off northern and southern Zhejiang. In general,there are abundant wave energy resources off Zhejiang, and the yearly wave occurrence frequency of exploitable wave energy is quite high.

The Beaufort Gyre was usually suggested as a main factor to control the residence time and moving direction of sea ice in the Arctic Ocean. Based on records of sediment color cycle, Mn content and foraminiferal abundance, we built up the orbital timescale for the core B85-D from the Alpha Ridge, and discussed variations of ice-rafted debris (IRD> 154 μm) in content, composition and provenance since the Late Quaternary. The results suggest that the most distinct variations occurred during the last glacial (MIS2 ~4) as remarked by the near zero contents of calcium and dolomite, indicating that the carbonate debris from Banks Is., Victoria Is. and District of Mackenzie did not deposit at the Alpha Ridge. The carbonate debris, transported by sea ice, was most likely heading to the Eurasian Basin along the off shore of the North America during the last glacial, when the Beaufort Gyre vanished. In contrast, the carbonate debris was mostly trapped in the Amerasian Basin during the last interglacial (MIS5), when the Beaufort Gyre became strong so as to deposit relatively high content of calcium and dolomite, which was up to 16. 4%. By comparison, is it indicated that the state of the Beaufort Gyre during the MIS6 was closely analogous to that during the MIS2~4,but its state during the glaials MIS8 and MIS10 similar to its state during the interglacial MIS5. Therefore,variations in the Beaufort Gyre are not strictly characterized by the glacial-interglacial cycles, which we speculate, to be modulated by the sea ice concentrationas well as the wind pressure.

The cobalt-rich (Co-rich) crust sample KXD28 was obtained from Mid-Pacific seamounts during DY105-12,14 cruise. The contents of soluble organic matter ( chloroform bitumen “A”) and its group compositions ( saturated hydrocarbon, aromatic hydrocarbons and resin),n-alkanes and isoprenoid hydrocarbon were analyzed quantitatively using gas chromatography (GC) internal standard method. Total organic carbon ( TOC) and organic carbon isotope ( δ¹³C) in the cobalt-rich crusts were also detected. Compared with the analyzed results from the sediments nearby metallogenic zone， and using the abundance data of organic matter composition recorded in the crust layer and in the seafloor sediments, the ecological environment of seamounts in the past， as well as the Co-rich crust forming environment and evolution characteristics were studied. Finally， the relationship between the composition of the crust and the environment of growth was investigated. And our principal conclusions show that: (1) The biomarkers of n-alkanes and isoprenoid hydrocarbons were detected in Co-rich crusts. According to the molecular characteristics index，main peak of carbon, EnC23^- /EnC24⁺，CPI, Pr/Ph，Pr/nC17 and Ph/nC18， it is indicated that crust sample KXD28 was originated mainly from the sinking or floating hydrophily macrophytes and homonemeaes with less terrigenous materials. The organic carbon isotopes also matched with the carbon isotope characteristics of marine aquatic organisms; (2) The changes of the organic carbon isotopes of crust were consistent with the changes of marine environment and climate during the crusts’growth. Before crusts formed, and in the early period of crusts’ growth, δC changed from positive to negative, corresponding to global cooling and Antarctic Bottom Water flowing into Pacific. During the late period of crusts’ growth, δ¹³C turned positive gradually, related to global warming and Antarctic Bottom Water receding.

The Empirical Orthogonal Function analysis (EOF analysis) is often used to analyze the raw data based on the multivariate statistical method. This method was applied to analyze the evolution of muddy tidal flat after the construction of the groins located in Zhejiang Rui'an. In the paper, the deviation matrix was split to the spatial and temporal eigenfunctions. The linear combination of three main empirical eigenfunctions was used to reflect the topographic change of tidal flat, which represent the overall change, seasonal change and accidental disturbance of the tidal flat respectively. In order to get general laws of muddy tidal evolution after the establishment of the groins, the relationship between dynamic process and geomorphology was discussed preliminary in this paper. Based on the coastal dynamic geomorphology theory, the factors that impact the tidal flat change in both spatial and temporal were discussed and the dynamic relationship between geomorphology and impact factors was analyzed. The second eigenfunction corresponding dynamic process was expounded in detail, and the result shows that wave is the main factor affecting the seasonal variation of muddy tidal flat in Zhejiang Rui' an.

Based on the Sea WiFS-derived chlorophyll-a (Chl-a) mass concentration and TRMM sea-surface temperature data from September 1997 to February 2007 from the South China Sea (SCS),seasonal variations of Chl-a and its relationship with sea surface temperature (SST) were studied. The results show that the Chl-a mass concentration of the SCS has remarkable seasonal variability. Generally the lowest phytoplankton Chl-a mass concentration(<0. 12 mg·m^-3) occurs in spring or summer with low wind speed and high SST (>28 C), while the highest Chl-a mass concentration (>0. 16 mg·m^-3) occurs in winter with the strongest monsoon wind and low SST (<27 C). The linear regression analysis shows that Chl-a mass concentration has obvious negative correlations with SST. Though the correlations level is different for the 4 typical sub-regions of the south,central, and west SCS and the upwelling zone southeast of V ietnam,the consistent negative correlations imply that the Chl-a mass concentration and phytoplankton biomass are controlled by vertical stratification reflected by the temperature variation. The SST is a key factor influencing the upper ocean stability and the strength of vertical exchanges, and thus controlling the variations of nutrients and phytoplankton.

Using the data of suspended particulate matter mass concentration measured in four seasonal cruises of spring in May to June 2011,summer in August 2009,autumn from November to December 2010,and winter from December 2009 to J anuary 2010,seasonal distributions of the suspended organic and inorganic matters in the surface-layer over the shelf of the East China Sea (ECS) were analyzed. The results show that the mass concentration of total suspended particulate matter (TSM) is higher in the winter half year than that in the summer half year, and higher inshore than offshore. The isolines are parallel to the shoreline as a whole. There is a turbid water tongue stretching southeastward with notably seasonal variation near 29°N off Zhejiang Province,and there are two centers of high mass concentration near the Changjiang River Estuary and Yushan Islands of Zhejiang Province and two centers of less high mass concentration centered at 32°N, 125°E and 30°N,127°E respectively all the year round. The high TSM mass concentration front (10 mg/L) is usually parallel to the shoreline. It occurs seasonally near the 40~60 m isobath and often separated into two parts in the northern ECS. The less high TSM mass concentration front (3 mg/L) is not parallel to the shoreline because of a turbid water tongue stretching southeastward all the year round at 29‘N. It appears near the 30~40 m isobath in the northern ECS,near the 50~90 m isobaths in the central ECS, and near the 50~80 m isobath in the southern ECS in different seasons. In contrast, the particulate organic matter (POM) mass concentration is higher in the summer half year than that in the winter half year, Like the TSM, there are two centers of high value and two centers of less high value seasonally. The distribution pattern and magnitude of the particulate inorganic matter (PIM) mass concentration is similar to that of TSM,but the contours shrink shoreward by about 0.5°. There are also two high value centers near the Changjiang River Estuary and off Zhejiang Province, but only one less high value center centered at 32° N, 125° E. The percentage of POM in the TSM from high to low is in the order of spring, summer, winter, fall and it is opposite for PIM.

Marine microorganisms in the tidal flat sediment from Zhenhai were isolated with pure culture method and bacterial community and diversity were analyzed. The tidal flat sediment sample was collected from Zhenhai, Zhejiang Province of China in June, 2008. The diluted sediment was plated on modified ZoBell medium agar plates. After incubation aerobically at 25 °C and 37 °C, strains were selected and purified. The 16S rRNA genes were amplified with primers 27F (5'-AGAGTTTGATCCTGGCTCAG-3') and 1492R (5’-GGTTACCTTGTTACGACTT-3') and sequenced. The sequences obtained were compared with closely related sequences of described bacteria from the EzTaxon-e online service. Sequence data were aligned with Clustal W and phylogenetic tree were constructed by the neighbor-joining method with the MEGA 5 program package.
Totally, 39 bacterial strains were isolated. Analysis of the 16S rRNA gene sequences show that the isolates were closely related to described bacteria and fell into four lineages: Firmicutes (20 strains, 51. 3%), Proteobacteria (12 strains, 30. 8%),Bacteroidetes (6 strains, 15. 4%) and Actinobacteria (1 strain, 2. 6%). Firmicutes strains belong to genera Bacillus, Ornithinibacillus and Thalassobacillus; Proteobacteria strains belong to genera Roseicyclus, Rhodobacter, Erythrobacter, J annaschia and Ruegeria of Alphaproteobacteria and genera Acinetobacter and Pseudomonas of Gammaproteobacteria; Bacteroidetes strains belong to genus Algori phagus and family Flavobacteriaceae; and Actinobacteria strains belong to genus Gordonia.
Bacilli and Alphaproteobacteria were the largest group in Firmicutes and Proteobacteria, respectively. They might play an important role in biogeochemical cycles in the coastal sediment ecosystem. Bacilli strains are heterotrophic bacteria, and their occurrence indicates that the tidal flat environment is rich in organic nutrition. 15 out of 20 (75%) of the isolated Bacilli strains showed closer phylogenetic relationship with the bacteria of land origin rather than bacteria of marine origin. In addition, strain ZH04 as well as ZH55 shared the highest 16S rRNA gene sequence similarities to the arsenic-resistant bacterium Bacillus indicus Sd/3T (99.9%); strain ZH41 as well as ZH43 shared 99.7% sequence similarity to the iron-and manganese reducing bacterium Bacillus subterraneus DSM 13966T; strain ZH56 were most related to Bacillus thioparans U3, which can oxidize manganese and remove cadmium, zinc, copper and lead. The discovery of strains related to absorption and oxo-reduction of heavy metals indicates heavy metal pollution of the offshore environment resulted from large amount of heavy metal sewage discharge in recent years and the impact of human activities on land on the coastal ecological environment. Of the 10 strains assigned to Alphaproteobacteria, up to 8 strains were assigned to Roseobacter lineage, including ZH40,ZH15, ZH32,ZH18, ZH36, ZH39,ZH50 and ZH17. The Roseobacter lineage is one of the richest marine microorganisms, and the bacteria of this group have multiple pathways for energy and carbon acquisition, including carbon monoxide and hydrogen sulfide oxidation, CO2 fixation, aerobic anoxygenic phototrophy and aromatic compound degradation, etc. Thus, the bacteria of Rhoseobacter lineage is called as‘ecological generalist’, which play important roles in the carbon and sulfur biogeochemical cycles of the offshore ecosystem.
In addition, strains ZH09,ZH15, ZH17 and ZH38 shared low 16S rRNA gene sequence similarities with Robiginitalea biformata HTCC2501T (93.6%),Rhodobacter aestuarii JA29T (97.1%),Ruegeria pomeroyi DSS-3T(97.2%) and Acinetobacter indicus A648T (96. 8%),respectively. The relatively low sequence similarities with described bacteria indicate that these strains may represent novel phylogenetic lineages in the offshore environment.
The research deepens our understanding of the diversity of culturable bacteria in the coastal sediment of Zhejiang Province and provides material for future exploitation and utilization of marine microorganism resources.

Lysis buffer method and trichloroacetic acid ( TCA)-acetone precipitation method both are the common methods in algal protein abstraction. We compared the 2-DE maps of these two protein extraction methods to find out the best protocol for Skeletonema costatum. As a result,the Lysis buffer-TCA-acetone method had better effect than the other two lysis buffer methods (lysis buffer-microcon &. lysis buffer-2-D clean-up kit) in removing the intracellular interferential factors, such as salt, nucleic acid, polyphenol and polysaccharide. The lysis buffer-TCA-acetone method and straight TCA-acetone precipitation method both represented clean background and clear protein dots in 2-DE maps while the later method showed better isoelect rofocusing results. We optimized the straight TCA-acetone precipitation methods. The TCA-acetone precipitation with 12 hours precipitation and a following ultrasonic cleaning process method was confirmed to be the appropiate sample preparation method for S. costatum for two-dimensional electrophoresis.

Fructosel, 6-bisphosphatase ( EC 3. 1. 3. 11) can catalyse the hydrolysis of fructose-l, 6-bisphosphate into fructose-6-phosphate and inorganic phosphate. It is one of the key enzymes in the gluconeogenic pathway. The full-length 1 357 bp FBP cDNA was isolateded from the liver of sea perch Lateolabrax japonicus with SMART RACE technology. It consists of a 42 bp5' UTR,a 301 bp 3' UTR and an open reading frame (ORF) of 1 014 bp,encoding a polypeptide of 337 amino acids with a predicted molecular weight of 36. 7 kD and electric point of 6. 90. Sequencing analysis of amino acid shows that the Lateolabrax japonicus FBP has high amino acid homology with the liver-type FBP gene from other species, and the homology is 94. 3% with Anopiopoma fimbria, 90. 8% with Osmerus mordax,89. 3% with Danio rerio, 88. 1% with Carassius gibelio and 84. 1% with Salmo salar. Phylogenetic analysis shows that Lateolabrax japonicus FBP clustered with liver-type FBP of fish, then with liver-type FBP of mammals, and still then clustered with muscle-type FBP of mammals to form a family. Semi-quantitative RT-PCR was used to determine the expression profiles of FBP from liver, muscle, heart, eye,intestine, kidney, fat, spleen, gill and brain. The results show that FBP was expressed only in liver, intestine and kidney. This conclusion is in consistent with the fact that liver, kidney and intestine are the major gluconeogenic tissues of teleost. These results indicate that the FBP obtained is of liver-type.

Based on the production of 3 fishing vessels, the weight of factors including gross tonnage, power of the main engine, operating days and underwater light power that affect the catching capability of light-purse seine vessels in Zhoushan waters were analyzed with AHP and the weights of the factors were defined according to their importance and evaluation model of factors affecting catching capability of light-purse seine vessels was established. The results show that the weight score for gross tonnage,power of the main engine, operating days and the underwater light power is 0.461 2, 0.342 4, 0. 1371 and 0.0594 respectively.