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This paper took the Zhejiang coast as the research domain and a 3D baroclinic nonlinear numerical model was used to simulate coastal upwelling on the basis of special topography along Zhejiang coast, with some variable dynamic factors, such as wind, Taiwan Warm Current, tides, and Changjiang runoff, taken into account. The results show that upwelling in banding shape occurs along Zhejiang coast in spring, with the strong upwelling centers occurring near Yushan Islands(28.40°N, 122.00°E) and Zhoushan Islands(30.70°N,122.60°~123.00°E). The wind, Taiwan Warm Current, and tides are main inducements of upwelling. The wind and Taiwan Warm Current influence entire upwelling band. Tides affect the two strong upwelling centers and the upwelling between 28.60°N and Zhoushan Islands, which parallels the Zhejiang coast. Changjiang runoff affect the upwelling near Zhoushan Islands, Changjiang Estuary and the two centers of upwelling.The dynamic cause of currents demonstrates that onshore velocities at the bottom depth contours of 20 m, 30 m, and 50 m near Zhoushan Islands are bigger than those surrounding areas. The phenomenon of upwelling is obvious. For the upwelling near Zhoushan, Coriolis force, horizontal advection, and vertical viscous force are main driving mechanisms of upwelling within 20~30 m. Coriolis force and pressure gradient force are main forcing factors below 30 m, while horizontal advection and vertical viscous force are weak.

The effects of environmental vertical wind shear (VWS) on the intensity, convection and precipitation asymmetries in Typhoon Matsa (0509) were analyzed based on the satellite observation data from various sources and NCEP/NCAR reanalysis wind. The results show that before and after Matsa's landfall, there is very close relationship between the VWS and Matsa's intensity, but the VWS is not a sole factor for Matsa's intensity variability. The VWS has a great impact on the asymmetric distribution of Matsa's convection and precipitation before and after its landfall. Heavy convection and rainfall generally occurr downshear to downshear-left of the VWS vector, showing a strong wavenumber-1 asymmetry.

Comparison for the visibility of 11 SAR polarization characteristics and σ⁰ images of internal waves were performed by using ALOS PALSAR quad-polarization SAR images. In SAR polarization characteristics of internal waves, the characteristic of Lambda values is the most obvious and then the characteristics of Entropy and Alpha are next. Compared with the images of σ⁰, the visibility of Lambda values for internal waves is better than that of copar-polarization σ⁰ images. For the Entropy and Alpha, the visibility of internal waves propagating along the range direction is better than that of the copar-polarization σ⁰ images; the visibility of internal waves propagating along the azimuth direction is slightly worse than that of the copar-polarization σ⁰ images. The characteristics of Entropy and Alpha are better than those of cross polarization σ⁰ images. The characteristics of internal waves for the images of the HH/VV, normalized coefficient of circular polarization, and Beta are not obvious; the characteristics of internal waves for the images of the HH/HV, VV/VH, Gamma, Delta, and Anisotropic index are fuzzy and internal waves can't be identified in these images.

A water-level correction method based on ocean tide dynamic model was studied and proposed. This method corrected astronomical tide projected by numerical simulation, combined with the correction of residual water level, and obtained the tide data of specific station. Combined with the actual data, this method compared with the traditional level correction method (the time- difference method and least squares fitting method). The results show that it has higher accuracy than that of traditional methods, and has unique advantages in more complex topography seas. This method can reduce the short-term tide gauge emplaced in the hydrographic surveying and charting,and use for fixing the missing tide level.

Based on the ocean current data observed by a moored buoy in the north of the East China Sea for two and a half months, the special structure characteristics of tidal current and the information of the residual current in the observed area were studied using the harmonic analysis method. The results show that it is dominated by the semidiurnal tide in this area. The type of tidal current in the depth less than 40 m belongs to irregular semidiurnal tide, while it belongs to regular semidiurnal tide in the depth more than 40 m. The tidal current is dominated by clockwise rotation in this area, and the proportion of the tidal current accounted for the ocean current increases with the depth. There are significant vertical variations in the tidal current ellipses elements. This research work will be helpful for understanding the vertical feature of tidal current in this area and the observed data can be provided to calibrate the ocean model on tidal current.

Five sedimentary basins develop in the northern continental margin of the South China Sea: the Southwest Taiwan Basin, the Pearl River Mouth Basin, the Qiongdongnan Basin, the Yinggehai Basin and the Zhongjiannan Basin. We summarized the research of five basins' gas seepage systems with the use of geophysical methods, focusing on three aspects: natural gas hydrate reservoirs, fluid migration pathways and seeping features near the seabed. The results show that BSRs indicating the presence of natural gas hydrate are found in the Southwest Taiwan Basin, the Pearl River Mouth Basin, and there is a large gas field in the Yinggehai Basin; five basins have active fluid migration, where we can find a variety of pathways: faults, diapirs, gas chimneys, polygonal faults, channels (canyon) and other fracture structures; seeping features near the seabed have been found in the Southwest Taiwan Basin, the Pearl River Mouth Basin, the Yinggehai Basin and the Zhongjiannan Basin. The northern continental margin of the South China Sea with wide distribution of the gas seepage systems deserves further studies.

Due to the bans or restrictions of brominated flame retardants all over the world, Dechlorane Plus (DP) has been considered as one of the recommended substitutes. However, as an additive, DP has a tendency to escape from the products and become an environmental contaminant, while limited information relevant to DP pollution in the environment has been reported. Residues and isomeric compositions of DP in four sediment cores from Hangzhou Bay, China were tested in the present study. The results show that the content levels of syn-DP and anti-DP, the two isomers of DP, vary from BDL~17.7 pg/g.dw(mean 2.9±3.2 pg/g.dw) and 1.4~38.1 pg/g.dw(mean 8.0±8.5 pg/g.dw), respectively, which are within the low level globally. Obvious differences exist between the DP levels of core 1 and the other 3 sediment cores, implying an additional contribution of DP pollution from the Jinshan Industrial Zone. However, the contents of DP vary little with depth. Moreover, the average f_syn values of DP are in the range of 0.25~0.28, suggesting that DP in Hangzhou Bay primarily originates from the long-distance transportation.

The application of acoustic taming has a broad prospect in the exploitation of marine ranching as a technology of controlling fish behavior. In order to know the effects of acoustic taming with different wave frequencies on Sparus macrocephalus, the behavior of Sparus macrocephalus was studied by means of acoustic taming using 300 Hz and 400 Hz sine wave alternate sounds in combination with temperature control and baits. The results showed that Sparus macrocephalus experienced three different periods to the revulsive effect of the alternate sounds, which were adaptation period, variation period and stabilization period. The response time of Sparus macrocephalus was decreasing gradually, and closed to the value of control group. The response time of trial group was significant higher than that of control group in the first four days (P<0.01), and there was a positive feedback to sound stimulation from the fifth day. Moreover, the response time was lower than the values of control group on the tenth day, which was the minimum response time of the entire trial process. The aggregation ratios increased gradually at the trial process, and there was extremely significant difference (P<0.01) from the fifth day between the trial group and control group, and the aggregation ratios were maintained at 100% after the seventh day. Besides, It was found that when acoustic challenged, the tamed Sparus macrocephalus in the hungry state were more excited than the well-fed state. The results indicated that 300 Hz and 400 Hz sine wave alternate sounds had a distinct revulsive effect on response and aggregation of Sparus macrocephalus, and the alternate sounds could be used as a valid possibility in acoustic taming of Sparus macrocephalus, which also could play a greater effect in the control of fish behavior combining with baits.

The conchocelis is very important for artificial seeding production in Porphyra cultivation and can be potentially used for separation and extraction of high value phycoerythrin. We investigated several influential factors related to phycoerythrin content of Porphyra haitanensis conchocelis and studied the optimal controlled culture conditions under which high content of phycoerythrin was obtained. Specific operational processes: initial conchocelis was obtained from carpospores release of mature Porphyra thallus and responses of conchocelis phycoerythrin content to environmental factors and optimal controlled culture conditions were determined based on the designation of an orthogonal experimentation with interactional analysis of three factors and three levels [L₂₇(3¹³)]. Results demonstrate that factors of temperature,light intensity and salinity have significant effects on phycoerythrin content (P≤0.048 1). There are factorial interaction occurrences between temperature and light intensity or salinity(P≤0.043 1). However there is no significant interaction between light intensity and salinity(P=0.469 8). The optimal controlled culture conditions for high content of phycoerythrin are: temperature 18 ℃、light intensity 1 500 lx and salinity 20 or 25. Under optimal controlled culture condition, conchocelis phycoerythrin content is as high as 64.73 mg/g.dw (average±SD: 58.24±5.07 mg/g.dw).

There are diverse origins of cultivated Sargassum fusiforme (Harv.) Setch. in Dongtou, Zhejiang Province. In this paper, 5 strains of S. fusiforme were investigated, of which one came from Korea, three were collected from Dongtou, Nanji Island, Dongji Island of Zhejiang Province, and the last one was from Shantou, Guangdong Province. Significant differences were found among the five strains in the algal weight and height. The strain of S. fusiforme from Korea had better growth advantages than others, so it could be used as target strain for breeding. The genetic diversity of S. fusiforme was analyzed by ISSR makers. The genetic distances among the samples were calculated by Popgen 32 and the cluster analysis was performed by UPGMA method. The results showed that 11 ISSR primers could amplify polymorphic and informative bands from the 36 screened primers. Total 219 DNA bands were amplified, of which 129 were polymorphic and the percentage of polymorphic loci reached to 58.9%. The genetic distances of the 5 samples varied from 0.151 0 to 0.382 4. In the dendrogram, five strains of S. fusiforme clustered into one clade and S. thunbergii were in the outgroup. The study revealed that the genetic diversity of the cultivated S. fusiforme in Dongtou was low on the DNA molecular level, which provided theoretical reference for the developing genetic resources conservation and superior seed breeding of S. fusiforme in the future.

Investigations were carried out to explore the changes of muscle and liver fatty acid composition and content in Pseudosciaena crocea during the winter. Gas chromatography-mass spectrometry (GC-MS) was used to detect fatty acid composition and content of its muscle and liver under the condition of sea water temperature at 20 ℃, 16 ℃, 12 ℃, 10 ℃ and 8 ℃ respectively. The results show that the content of unsaturated fatty acid increases with the reduction of water temperature, especially the content of EPA[C20:5(n-3)], from 5.71% at 20 ℃ to 8.06% at 8 ℃ in muscle and from 6.76% at 20 ℃ to 8.44% at 8 ℃ in liver. Therefore, with no feeding condition during the winter, saturated fatty acid decreases and unsaturated fatty acid increases through transformation and metabolism of fatty acid by organism itself to keep cell membranes fluidity and against the cold.

Based on the data of environmental survey of Shuangdao Bay in 2012, the distribution patterns and ecological risk assessment of heavy metals in seawater and surface sediments were analyzed. The results show that the contents of Cu and Pb in seawater are higher in the middle and end of the bay, Zn and Cr are the highest in the end of the bay and the lowest in the external bay, Cd and Hg are the lowest in the middle of the bay, while the distribution of As is uniform. Compared with other estuaries in adjacent area, all heavy metals except Zn and Pb show a higher level. The contents of heavy metals in surface sediments are low, the distributions of Hg and Cd in the mid bay and Cu, Pb and Cr in the external bay are higher than those in other areas. The correlation analysis show that no significant relationship is found between organic carbon and heavy metals in surface sediments. The ecological risk assessment indicates that the pollution of heavy metals in seawater is in the lowest level, the surface sediments has low to medium potential for biological toxicity effect, the sequence of ecological risk intensity caused by different heavy metals is Pb>As>Cu>Hg>Cr=Cd>Zn.