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Based on satellite remote sensing products, the seasonal and interannual variations in the wind and wave over the South China Sea (SCS) were presented in the study. A vector empirical orthogonal function (VEOF) method was employed to study the temporal and spatial patterns of the wind field. Results indicate that the first VEOF is a seasonal oscillation mode, which represents the monsoon feature in the SCS. The second VEOF is an approximate annual oscillation mode, it represents the wind field features during the monsoon transition period. The third VEOF shows that the wind field is the land-sea interaction mode. For SWH, an empirical orthogonal function (EOF) method was employed and the similar two modes are forced by the first two modes of wind data, the third mode is caused by the bottom topography variation. The correlation coefficient (CC) between wind field's first mode and SWH's first mode is 0.76, which shows that the wave variation is forced by the sea surface wind. The two third modes are nearly unconnected, there may be a link between the bottom topography and SWH's third mode.

Based on the high resolution satellite Sea Surface Temperature (SST) and wind data, the decadal variation of the warm tongue and sea surface wind field of East China Sea (ECS) Kuroshio during spring (March-May) were analyzed using the Empirical Orthogonal Function (EOF) and Composite Analysis methods. The results show that: the Kuroshio warm tongue in spring exists significant decadal variation, and experiences a phase change in 1996/1997. The phase change is mainly influenced by the North Pacific Gyre Oscillation (NPGO). Further study find that there is a significant negative correlation between the SST and wind divergence field on decadal time scale. Composite Analysis indicates that the abnormal warming of continental shelf in ECS mainly influence the negative correlation.

In order to establish a sufficient available data both for the spatial coverage and temporal duration, the reflectance data of three satellites of Aqua, Terra and SeaWiFS from July 27 to August 8, 2006 were merged by linear regression. A coastal water extension process was analyzed with the established data in the area adjacent to the Changjiang River Estuary. The results show that there is an obvious extension process from July 27 to August 8, 2006. During the extension process, the remote sensing reflectance of the coastal water decreases with the increase of distance from shore, the coastal water tongue extends almost in the east-west direction. According to the spatial coverage of reflectance and its concentration, the whole process is further divided into two stages, i.e., an eastward growing period from July 23 to August 2, and a westward extinction period from August 3 to August 8. During the eastward growing period, the coastal water tongue extends gradually to the east along the latitude of 32.4°N, and reaches the east-most longitude of 124.4°E. On the way to east, the coastal water tongue gradually narrows its shape and decreases its concentration. The moving speed of the tip of coastal water tongue boundary changes from 17.6 km/d to 33.4 km/d, with an average speed of 24.5 km/d. During the westward extinction period from August 3 to August 8, the coastal water tongue is getting narrow as well as decreasing concentration as a whole, but remains the spatial position unchanged. Based on the preliminary analysis of the mechanism of such process, it is believed that the tidal current would constrain the movement of coastal current along the coastal during the eastward growing period. The southerly wind during the eastward growing period and the easterly wind during the westward extinction period are found most-likely to be the cause of the coastal water extension process.

The wave field caused by tropical cyclone “Thane” in the Bay of Bengal during December 2011 was simulated by using WW3(WAVEWATCH-Ⅲ) wave model with CCMP (Cross-Calibrated, Multi-Platform) wind data as the driving field. Results show that: (1) With CCMP wind data as the driving field, the WW3 wave model can simulate the wave field caused by tropical cyclone “Thane” properly. The simulated SWH (significant wave height) has good consistent with the observed SWH. Simulated value is slightly smaller than observed value when the SWH is smaller than 2 meters or larger than 5 meters. The simulated value is slightly greater than observed value when the SWH is between 2 meters and 5 meters. (2) There are some differences between wind field and wave field caused by tropical cyclone “Thane”. The gale district distributes more evenly around the cyclone. When the cyclone is in the middle of the ocean, big wave areas mainly distribute in the right semicircle, and big wave areas mainly distribute in the front of the cyclone in offshore. (3) During tropical cyclone “Thane”, the wave direction has good consistency with the wind direction except the second quadrant. In the second quadrant, the wind direction is northwest, but the wave direction is north.

The chlorophyll-a concentration is one of important index for the water environment. Based on the measured chlorophyll-a concentration, water spectral data and FY-3A moderate resolution imaging spectrometer data, the feasibility of using FY-3A to monitor the chlorophyll-a concentration in Zhanjiang Bay and its adjacent waters was researched. The results show that the waters of the Zhanjiang Bay is close to case one water, and case two water is mainly distributed in the narrow and enclosed area near the Zhanjiang Harbour; and the OC4 algorithm can be used to monitor the remote sensing of the chlorophyll-a concentration in the Zhanjiang Bay. The measured chlorophyll-a concentration has good correlation with the retrieved one, and the correlation coefficient R is better than 0.7. FY-3A medium resolution imaging spectrometer data can reflect the distribution of chlorophyll-a concentration in Zhanjiang Bay.

Based on the connecting line project of Zhoushan Island-Mainland Link Project, the experiment of a friction pile was developed to study the application of self-balanced test method in soft strata,and it was verified with the traditional piling-up weights method. The paper introduced the whole process and design points of the method in design, field test and data analysis stage. And an improved method for the use to measure the displacements of the upper and lower shaft was put forword. This new method can avoid the influence of the latent concrete defect in the cell position. The coefficient of negative skin friction in soft strata and the bearing capacity of the test pile was also measured in the experiment. The test results fit the designed requirements, while the bearing capacity of the test pile also meet the designed requirements. This design and the coefficient can be a reference for the soft strata, and the self-balanced test method has its rationality and accuracy in engineering application.

There are many islands and reefs out of the Hangzhou Bay, and the wave propagation mechanism is complex. In order to understand characteristics of wave distribution of the sea area, MIKE 21 SW module was used to establish a numerical model of wave for the Hangzhou Bay, and the model was validated with the observed wave data. The extreme wave data of Shengshan Marine Observation Station between 1970—2002 was used to calculate wave elements with a return period of 50 years, as the boundary conditions of the model. And then, the designed wave with a return period of 50 years in the Hangzhou Bay was simulated, while the characteristics of wave propagation was also analysed. The results show that the model is suitable to simulate the wave propagation in the Hangzhou Bay. Comparing with the wave height of the open sea, the wave height in the Hangzhou Bay is significantly smaller, and it is assumed that many islands and reefs outside of the Hangzhou Bay may play very good protection functions.

The distribution and enrichment of the heavy metals in surface sediments nearby Hebao Island, Pearl River Estuary were studied, the correlation among the heavy metals (Cu, Zn, Pb, Cd, Hg, As, Cr) and the contents of TOC in the surface sediments were also analyzed. In addition, the method of potential ecological risk index presented by Lars Hakanson was used to assess the heavy metals' ecological risk. The results show that the contents of Cd, Hg, Cr and As appear higher nearby Hebao Island, while those of Zn, Pb and Cu has no apparent rule. The order of the enrichment of heavy metals is Cd＞Zn＞Cu＞Hg＞As＞Cr＞Pb. The correlation analysis indicates that Cu significantly correlated with Zn, while As, Hg, Cr and Cd all have highly significant correlation; the organic matter is an important influencing factor of the migration and transformation of heavy metals.The assessment results of heavy metals' ecological risk reveal that Cd and Hg belong to middle potential ecological risk, while other heavy metals belong to light potential ecological risk. The order of potential ecological risk factors is Cd＞Hg＞As＞Pb＞Cu＞Cr＞Zn.

In order to better understand the pollution state of sediments in a dumping site, the acid volatile sulfides (AVS) and simultaneously extracted metals (SEM) of surface sediments collected from the marine dumping site of Yangshan were determined, while distributions of AVS, ΣSEM, ΣSEM-AVS were also analyzed. The results show that the AVS in the surface sediments of the dumping site and nearby area are 0.55~2.62 μmol·g^-1(before dumping), 0.83~1.65 μmol·g^-1(dumping) and 0.51~1.23 μmol·g^-1(after dumping) respectively, the contents of AVS present a decline trend after dumping, and the AVS in sediments is higher than that in nearby area after dumping. The mean values of ΣSEM in nearby area are 2.80 μmol·g^-1(before dumping), 2.79 μmol·g^-1(dumping) and 2.60 μmol·g^-1 (after dumping) respectively the contents of ΣSEM also present a decline trend after dumping, and the contents of ΣSEM are enriched toward to dumping site. The order of the contribution of heavy metal to ΣSEM is Zn＞Cr＞Cu＞Pb＞Cd, with the contribution of zinc basically being>35%, chromium>20%, cadmium<1%. Therefore, the distribution is mainly controlled by zinc and chromium. The different values of ΣSEM-AVS are larger than zero and lower in the dumping site than that in nearby area, which indicates that the metals (SEM) in the surface sediments of the dumping site probably have some toxicity to the life.

Based on the monitoring data in the Sanmen Bay in August 1997 and October 2011, the distribution features of nitrogen, phosphorus and the changes of the nutrient salts at this section in the past 15 years were analyzed.The results show that the concentration of nitrogen and phosphorus have doubled since 1997 and the degree of eutrophication in the Sanmen Bay is from mild to serious. According to the nutrient structure, phosphorus still is the limitation factor of phytoplankton growth in the Sanmen Bay. It is also found that the excessive development of mariculture has improved the concentration of the nutrient salts directly. And it is suggested that the scale of marine aquaculture and adjusting the structure of mariculture as well as strengthening the pollution control should be performed in order to control the intensifying eutrophication level in the Sanmen Bay. It is needed to obtain the effective coordination of aquaculture economic and ecological environment, and the sustainable development is recommended.

In order to study the accumulation and consumption of nutrients of Mytilus coruscus in different gonad developmental stages, the values of meat condition index, water contents and biochemical compositions of M. coruscus in three age groups were determined from proliferation stage, growing stage, maturation stage, spawning stage to spent stage.The results show that (1) The changes of meat condition index and water contents are not significant(P>0.05)in same development stage, while the changes in different development stages are significant(P<0.05). The maximum values of meat condition index in three groups are 17.76%~19.21% in maturation stage, but the values of meat condition index are the lowest in spent stage, and the values in maturation stage are 3.15 times as high as those in spent stage; The maximum values of water contents in three groups are 93.29%~95.32% in spent stage, while those are the lowest in maturation stage, and the values of water contents in spent stage are 1.15 times as high as those in maturation stage. (2) The changes of crude proteins, crude lipids, ash contents and glycogen in different developmental stages are significant(P<0.05). The maximum values of crude proteins and crude lipids respectively are 72.01% and 13.52% in maturation stage. Furthermore, the maximum of ash contents is 7.59% in spent stage, and glycogen is 13.56% in spawning stage. The values of crude proteins and crude lipids are the lowest in spent stage and in proliferation stage respectively. The values of ash contents and glycogen are lowest in maturation stage. (3) In conclusion, changes of accumulation and consumption of crude proteins are anastomosed with changes of meat condition index. This study indicates that the meat condition index rises due to absorption and storage of energy by M. coruscus in gametogenesis, while it descends because of the release of gametes.

Digestive enzymes are important in reflecting the physiological state of digestion and the capacity of nutrition utilization. In the present study, digestive enzymes activity in hepatopancreas of Portunus trituberculatus after molting were studied. The results showed that pepsin, tryptase and amylase were the highest at 4~6 d after molting. Lipase activity reached the highest at 6 d after molting. Cellulase was the highest at 10~12 d after molting, though it maintained at a lower level in all the detected time. Chitinase was the highest at 4 d after molting. After molting, P. trituberculatus had high level of pepsin and tryptase activity, while the activity of cellulase and chitinase were low, which might be due to the characterization that P. trituberculatus mainly lived on animal derived food. The lipase activity in hepatopancreas was low, and it might be result from that the optimal determination condition was not provided. Compared to the other time, activity of all the detected digestive enzyme were high at 6 d after molting, which indicated that the crabs of this stage had higher food digestive capacity than that in other time. This result may help to provide reasonable reference for food providing in aquaculture of crab culture.

Features of the phytoplankton community were studied based on the data of phytoplankton net samples collected from a grid of 20 stations in the Tianjin nearshore waters of Bohai Bay in spring of 2012. A total of 2 phyla including 17 genera and 28 species of phytoplankton were identified in the present study, in which 92.9% are diatoms and 7.1% are dinoflagellates. The main phytoplankton groups are eurythermal and neritic autochthonous species. The dominant species are Guinardia delicatula, Odontella sinensis, Ditylum brightwellii and Coscinodiscus granii. The horizontal patterns of phytoplankton cell abundance are controlled by that of diatoms. They are high in Tanggu, Dagang and Qikou of the Bohai Bay. The species at 20 stations are grouped into five ecotypes according to the result of cluster analysis. The Shannon-Wiener diversity indexes range from 0.43 to 3.59 with an average of 2.15, with a decreasing trend from the north and south to the middle. The 4 factors of temperature, DO, pH and inorganic nitrogen have the maximum ranking correlation coefficient with phytoplankton species composition and cell abundance distribution, and these 4 environmental factors are the best explanation for the community structure.