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The tropical Indian Ocean Sea Surface Temperature Anomaly (SSTA) and the Indian Ocean Dipole (IOD) indices are predicted, using the multiple linear regression model, the Markov model and the neural network model respectively. 63 years' hindcast experiments are set up to compare the differences between linear and nonlinear statistical models in detail. And the results reveal that the statistical models are little different from the complicated dynamic model. Their skillful prediction (correlation coefficients above 0.5) could reach 3 months for DMI, about 5-6 months for EIO index and 8-9 months for WIO. Since the IOD event has a strong seasonal phase lock, the DMI can be predicted previously for 4 months in fall. When the synchronistic ENSO index is added as a predictor, the prediction skill, especially the IOD peak, will be improved. The complicated neural network and the simple regression model are proved to be with a similar prediction skill.

The Complex EOF (CEOF) analysis of the upper abnormal circulation of the tropical Indian Ocean in May was carried out based on 52 years Carton data. The inter-annual and inter-decadal variation of Wyrtki Jet, and the relationship between the Jet and the Asian tropical summer monsoon were presented. The main results show that the first mode could be called as Wyrtki Jet mode which reflected the general intensity of Wyrtki Jet in May of every year. The first mode had obvious inter-annual variation in every 8 years, which was consistent with one of the inter-annual variations of Asian summer monsoon. It also had obvious inter-decadal variations in every 17 and 23 years. The latter was consistent with the PDO period of the main climate mode in North Pacific. When the intensity of Wyrtki Jet was weaker, the estabishment data of the summer monsoon in South China Sea and South Asia was usually earlier, and the summer monsoon in South China Sea was most likely stronger, and vice versa. The second mode reflected the non-uniformity of Wyrtki Jet in the east and west directions of equatorial Indian Ocean. It had very obvious inter-decadal variations in every 11 and 18-19 years. The former was consistent with the period of NPGO of the secondary climate mode in North Pacific. The second mode also had inter-annual variation in every 5 years.

The shelf slope and the Taiwan Strait are two main boundaries of the East China Sea, which obtain considerable heat and salinity as well as nutrients from the northwestern Pacific and the South China Sea. In this paper, based on the satellite drifter trajectories, a reliable method is established for estimating the cross-boundary exchanges by mapping the irregularly-distributed trajectories to the regular homogeneous grid. With this method, the calculated density of trajectories reveals the location of the Kuroshio main axis, and further indicates significant cross-slope exchanges. The statistical results reveal the remarkable region feature of water exchanges along the shelf slope of the East China Sea, showing seven dynamic exchange zones, i.e., three inflow (shoreward) zones and four outflow (offshore) zones. The study also shows that the cross-slope exchange has prominent seasonality. The most significant exchange and the most distinctive inflow occurs in autumn while the weakest in spring. The exchange through the Taiwan Strait is mainly northward and the most intense exchange occurs in the eastern side of the strait. The exchange through the Taiwan Strait reaches the strongest in summer but the weakest in spring and in winter.

Suspended particulate matter (SPM) plays an important role in determining the light field under water, which then affects the primary production and waters ecological environment. Therefore, SPM concentration is one of the important parameters for water quality and hydrographic environment monitoring.Based on a total of 89 in-situ SPM concentration and spectral data collected from June to July and from November to December 2011, the spectral characteristics of suspended matter in the Yellow River Estuary and its adjacent waters were analyzed. And an empirical inversion algorithms for SPM concentration with different combinations of bands or band ratios was established. The result showed that the algorithm with combining the R_rs655/R_rs560 and R_rs865 was the best, the APD of algorithm was 25.65%, and the correlation was 0.95. Using the R_rs retrieved from Landsat 8 OLI data and the SPM algorithm, 7 maps of the SPM concentration in the Yellow River Estuary and its adjacent waters from 2014 to 2016 were obtained. The result indicated that the SPM concentration reduced gradually from the coastal to offshore waters, and the value of SPM concentration had significant changes during different periods.

With the rapid development of the eastern coastal harbor region and the continuous formation of man-made landforms, the geomorphic pattern of the harbor area has also changed accordingly. Quantitative study of the spatial and temporal pattern changes of coastal artificial constructed landform can be a comprehensive scientific and practical evaluation of human construction behavior, and it has a certain scientific and practical value. Four periods TM/OLI remote sensing images of 1990, 2000, 2010 and 2015 from Xiangshangang Bay were taken as the main data source, the changes of artificial constructed landform intensity during the last 25 years in Xiangshangang coastal zone were analyzed and its spatial pattern evolution was further explored. The research shows: (1) The development trend of artificial constructed landform in the coastal zone of Xiangshangang Bay appears a rapid growth in the early stage, a slow increase in the medium term and a strong follow-up, and its area growth has significant historical characteristics. (2) The number of punctate and surface topographic patches in each county (city) area rise in fluctuation as a whole, but its internal development level varies greatly. The rate and degree of geomorphic development in Ninghai County and Xiangshan County are in the lead. (3) The pattern evolution process can be divided into four important stages: point-like dispersion period, surface aggregation period, strip extension period and compound, update the diffusion period.

Two core sediment samples collected in the area of 16^th July 2010 split oil accident by box crab during April 2013. The biological dispersant were used during the split treatment in heavy pollution area. Site BQ050 and Site BQ007 located in the area where biological dispersant and chemical dispersant were used, respectively. The TOC content, soluble organic content (asphalt A), δ¹³C_org value and ²¹⁰Pb_ex of sediments were analyzed for identifying the contaminated organic matters. The sediments of Site BQ050 have higher organic matter content (TOC: 0.58%~1.51%, mean: 1.15%; asphalt A: 0.061 5%~0.566 4%, mean: 0.174 9%, up to 0.566 4% in depth 10~12 cm), heavier δ¹³C_org value(-22.2‰~-20.5‰PDB, mean: -21.74‰PDB), and higher asphalt A/TOC ratio (7.0%~34.8%, mean: 14.13%) indicating that the organic matter characterized by exotic. Meanwhile, the δ¹³C_org values of sediments are similar, which shows the same organic input in the depth from 2 cm to 16 cm. The ²¹⁰Pb_ex of sediments has the similar distribution to the asphalt A. The sediments of Site BQ007 have much lower asphalt A content and asphalt A/TOC ratio compared to the sediments of Site BQ050, and the ²¹⁰Pb_ex distribution is normal. The content of ²¹⁰Pb_ex decreasing with depth shows the logarithmic correlation. The exotic organic matter is low in the Site BQ007. The split oil(characterized by asphalt A)has been migrated to about depth of 16 cm in the Site BQ050 until April 2013.

The water exchange capacity of the encircled harbor has an important influence on the water quality of the harbor basin, adding water exchange channel is an effective measure to improve it. Taking the seawall reconstruction project of Zhapo fishing port as an example, the irregular triangular mesh and finite volume method were employed, based on the research results of tidal current numerical simulation, a two-dimensional convection-diffusion model was established. The numerical simulation research of water exchange capacity before and after the expansion of Zhapo fishing port was carried out, and the half exchange period and water exchange rate of the harbor before and after the project were evaluated. The results show that the water exchange capacity of Zhapo fishing port is strong, the half-life time of water body is 129 hours before the engineering, and 104 hours after the project. After the project, the Zhouzaixia breakwater is changed into a culvert-type bridge, so that the water body exchange channel is formed between the fishing port and the offshore, the water body interaction and water body exchange capacity inside and outside the harbor basin are increased, and the corresponding water body exchange capacity is enhanced. As a comparison, two aquaculture areas outside the harbor basin have strong water exchange capacity as they are well connected with the sea, so the limit change in water exchange capacity caused by the project is reasonable.

The phenomenon of phytoplankton blooms in the northwest of Luzon Island is frequently observed in winter. In our study, using the multi-satellite merged ocean color remote sensing data from November 1999 to February 2015 in the northwestern region of Luzon Island, the spatial and temporal changes of Chl-a concentration in long time series were investigated by means of the empirical orthogonal function (EOF) decomposition method and multiple correlation analysis(MCA). Combined with physical environmental parameters such as wind speed(WS), sea surface temperature(SST) and sea level anomalies(SLA), the relationship between Chl-a and surrounding sea environments was then investigated in the study. The results show that centers of winter Chl-a blooms in northwest of Luzon Island appear often at the location of about (19°N, 119°E). Significant multiple correlation coefficient (R=0.782 6, P<0.05) from the multiple correlation analysis between Chl-a and oceanic conditions indicates that the wind parallel to the coastline and the wind stress curls enhance winter upwelling in the study area, increasing the input of the nutrients into the upper layer, which is probably the main mechanism of the formation of phytoplankton blooms in the area. At the same time, the advection effect of the background flow field is likely to induce the upwelling area to be inconsistent with the center of phytoplankton blooms, triggering the phenomenon that the centers of phytoplankton blooms shifted northward along with the water body in the area.

The pathogens causing mortality in Yesso scallop (Patinopecten yessoensisis) larvae in the hatchery of Zhangzidao Group Co. Ltd. were identified. A high mortality of the Yesso scallop larvae occurred during the seedling process: the larvae lost their ability to swim, their cilia fell off and their valves closed, they then sank to the bottom of the nursery pond and died. Vibrio has been reported as the primary pathogen for massive mortalities of different bivalves both in hatchery and in the field worldwide. Total viable vibrios counts in moribund larvae were 1.12×10⁴ CFU/g on Tryptone Citrate Bile Sucrose agar plates. Two dominant strains, named V1 and V2, accounted for 64.3% and 32.1% of total vibrios counts respectively. Blood agar plates were used to measure hemolysis of isolated strains. Strain V1 exhibited beta hemolysis, while strain V2 exhibited alpha hemolysis. A challenge test showed that the signs of infected larvae were identical to those of natural moribund larvae, the cumulative mortality caused by strains V1 and V2 was significantly higher than that of the control (P<0.05) and bacteria were re-isolated from the dead larvae. Strains V1 (GenBank Accession No: KR232924) and V2 (GenBank Accession No: KF232925) shared 99.9% and 99.2% identity with Vibrio splendidus ctt 31/5 and Vibrio tasmaniensis 007, respectively, by 16S rDNA sequencing. The presence of genes coding for virulence factors was examined by PCR analysis, showing that strain V1 possessed the extracellular metalloprotease (vsm) gene. Antibiotic susceptibility assays showed that both strains were sensitive to the rifampicin, florfenicol and sulfafurazole.

As one of the most important marine groups, zooplankton are very sensitive to climate change and anthropogenic activities. In this study, the structures and variations of zooplankton community were considered on the basis of monitoring data in Bohai Bay in the summer from 2004 to 2015, and the relationship between the zooplankton and environmental variables was examined. Results showed that species number and biodiversity indices of zooplankton appeared an increasing trend in Bohai Bay. Among 7 phyla identified, two major groups of Arthropoda and Coelenterata showed an increasing abundance in recent years. As a result, the zooplankton composition in the Bohai Bay had changed dramatically during 12 years: the number of large-sized copepods such as Calanus sinicus and Labidocera euchaeta had decreased gradually, while small copepods such as Acartia pacifica and Centropages dorsispinatus as well as gelatinous zooplankton such as Oikopleura dioica and Eirene ceylonensis had expanded. It was revealed that the zooplankton community variation mainly related with the environmental variables such as changes in temperature, salinity and nutrients concentration in Bohai Bay.

A study was carried out by “Dayang Yihao” from May 25 to June 17,2011. The meiofauna samples were collected from 7 stations in the south Mid-Atlantic Ridge. The results showed that 10 benthic groups were founded from the surveyed area. The average abundance and biomass of meiofauna were (60.63±54.77) ind/10 cm² and (9.42±8.92) μg/10 cm², respectively. Nematodes were present the great abundance (47.42±47.99) ind/10 cm²,accounting for 78.21% of total abundance of meiofauna in study area. Besides,Sarcomastigophora and Copepod were also found to be the dominant taxa, constituting 16.63% and 3.91% of total abundance of meiofauna,respectively. Copepod had the most biomass in the 10 benthic groups,followed by Nematoda and Sarcomastigophora. The analysis of vertical distribution has shown that the abundance of meiofauna decreased with the depth in the sediment. About 73.55% of meiofauna live in the top 0-2 cm layer. In terms of body size,the range of 32-125 μm accounted for 75.32% of meiofauna.