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Based on sea surface salinity (SSS) observations from Argo profiling floats during 1996—2012, SSS response to typhoons was analyzed by a synthetic analytical method. The results show that there exists an apparent asymmetry in the SSS response to typhoons: the SSS on the right side of the track increases markedly, however on the left side,it increases within radius of 50 knots wind speed (R₅₀) while decreases outside the R₅₀. Further analyses indicate that intensity, translation speed of typhoon and ocean mixed layer depth all have significant impacts on the SSS response. Strong or slow moving typhoons can produce SSS rises in a large area, whereas SSS increases (decreases) on the right (left) side of the track during the period of weak or fast moving typhoons. In summer (Jun.-Sep.), SSS generally rises more in magnitude and area after the passage of typhoon in regions of shallow mixed layer than in deep one,where SSS rises slightly within radius of 2R₅₀ and decreases on the left side far away from typhoon track.

Twenty historical typhoons which had a great impact on the Zhoushan sea area, were selected to perform analyses and inductions of the measured tidal level data at Dinghai station. It was found that in these twenty typhoons, the maximum storm surge was 207.1 cm under the Typhoon 5612, and the maximum storm high tidal level was 283.7 cm under the Typhoon 9711. Further, a 3D baroclinic hydrodynamics model, SELFE, was used to establish an unstructured triangular grid astronomical tide-storm surge coupled model, through adding the typhoon pressure field and wind field modules. The numerical results show that the baroclinic effect is more obvious while the nonlinear coupling is relatively weaker. But the two-tides-coupled storm surge data are still better than the single-factor data and closer to the measured data. On this basis, in the north and south of the original path of the Typhoon 5612, two parallel paths at certain intervals were designed respectively. The corresponding results show that the supposed typhoon which adopts the parameters of the Typhoon 5612 and moves along the S1 parallel path in the south of the original typhoon path at a distance interval of a maximum wind radius, can induce the probable maximum storm surge of approximately 243.9 cm. Finally, supposing that the probable maximum storm surge separately encounters the astronomical high, middle or low tidal level, it is found that there appears a probable maximum storm high tidal level of about 400 cm when encountering the astronomical high tide.

By using RS and GIS technology, four satellites remote sensing images of 1970, 1992, 2003 and 2014 were used to create the maps of land use status in Xiushan Island. Intensity analytical method was applied to quantify the annual intensity of the changes at three levels: time interval, category, and transition. The results show that forest and grass land, cropland, construction land and tideland are the main types in Xiushan Island. Overall, the transforming rate of land use type increases initially and then decreases afterwards. The main directions of land use type transfer were the conversions from cropland to construction land. Analyses of the results reveal that the land use change is associated with the land policy, economic growth and employment structure.

Aiming to the demand of sea area dynamic changes monitoring, two periods of remote sensing dynamic monitoring from September, 2012 to October, 2013 were carried in Tangshan. The results show that the sea area changes in Tangshan have the characteristics of great quantity, large area and high frequency. The main reasons for the sea area change are human developmental activities such as land reclamation, infrastructure construction and reclamation aquaculture. According to the demand of remote sensing monitoring, the monitoring model, the monitoring frequency, the monitoring time and the business system of the dynamic monitoring of sea area were researched. The model of remote sensing information of sea area dynamic changes was constructed. Finally, the design scheme of the business monitoring system of sea area using dynamic changes with remote sensing was presented.

As a major project lying in the Changjiang Estuary, Qingcaosha reservoir leads to change of river regime in the North Channel markedly. The change of river regime could induce change of current field and sediment concentration, and then influence bed erosion and deposition. The three-dimensional hydrodynamic and sediment model were used to calculate and analyze the impacts of the project on current filed, sediment concentration, erosion and deposition in area around the reservoir. After the project, width of upper reaches of the North Channel was narrowed, which results in increase of both current speed and sediment concentration in the major channel on the north of Qingcaosha reservoir. On the contrary, the current speed and sediment concentration decrease in areas on east of the reservoir, lower reaches of the North Channel and sand bar due to the decrease of river discharge and tidal prism flowing into the North Channel. Using the formula of bed erosion and deposition based on experience and theory, and the modeled current, sediment concentration and water level, the erosion and deposition caused by reservoir project was calculated. Strong erosion occurs in the North Channel on north of reservoir, with maximum of 3 m, which matches well both in shapes and values with the observed depth change before and after the project. The numerical model simulated the distributions and magnitude of bed erosion and deposition fairly well caused by Qingcaosha reservoir project.

Research on tidal flat evolution at strong-tide bay is important for marine exploitation, environmental protection and disaster prevention. By using remote sensing and GIS technology, tide flat evolution in a strong tide bay-Wendu Bay in north Fujian Province was studied. The conclusions are showed as follows: Since 1991, tidal flat at the bayhead of Wendu Bay is in a silting state, and the deposition rate is increasing especially after 2005. The main reason of tidal flat siltation may be the bay mouth narrowing by bay reclamation, which results in flow velocity increasing and seabed scouring, so the scouring sediment at bay mouth can be transported to the bayhead and finally accumulates on the tidal flat at bayhead.

The growing inhibitory properties on Isochrysis galbana, Platymonas subcordiformis and Navicula of thirteen 2-(N-arylaminomethyl)-3-oxo-benzo[d]isothiazoles were investigated, and the effects on biological activity of barnacle nauplii were also studied. The results indicate that the tested compounds have favourable growing inhibitory activities to the marine algas, and the better inhibitory activities are on Isochrysis galbana and Platymonas subcordiformis. The results also indicate when the lowest concentration is 2.0 mg/L, the tested compounds show a favourable growing inhibitory activity on barnacle larvae except the compound g and l. The relationship between compounds' structure and plankton growth inhibitory activity reveals that meta-substituent is better than para-substituent.

Our knowledge on diazotrophs is limited in the Indian Ocean, which is considered an important source of biological N₂ fixation of the global ocean. Phylogenetic diversity of nifH genes in the southwest Indian Ocean was studied through cloning and sequencing methods. After sequences were checked, two nifH gene libraries were established. Overall, 76 nifH gene sequences are recovered from Station CTD13, including 46 nifH gene sequences of 10 OTUs from libraries CTD13-30 m, and 30 nifH gene sequences of 8 OTUs from libraries CTD13-125 m, respectively. Results of phylogenetic analysis show that most nifH gene sequences fall into Cluster I and III, only 3 recovered nifH gene sequences are grouped with Cluster II. In Cluster I, most of nifH gene sequences cluster with unicellular cyanobacteria Group B, while in Cluster III, most nifH gene sequences are closely related with uncultured clone from active sludge. No nifH gene sequences clustered with Trichodesmium are recovered, which may be attributed to low water temperature. In general, diazotroph community in the southwest Indian Ocean is different from those in tropical and subtropical oligotrophic ocean.

The rapid development of cage culture has brought high pressure to the marine ecological environment in recent years. Although the environmental quality of cage culture area has been analysed and evaluated at different aspects by scholars, there is lack of universally accepted evaluation criterias and methods, and integrated assessment in these researches. In this study, by using analytic hierarchy process(AHP), a comprehensive indicator system for environmental quality evaluation of cage culture area was constructed from two aspects: the environmental suitability, the quality and safety of aquatic products. Based on the historical and current monitoring data of cage culture area in the Xihu Bay, Ningbo City, along with related literatures, the evaluating indicators were selected, and the evaluation criterias were determined. Combined with the index evaluation, these indicators were applied to evaluate the environmental quality of cage culture area in the Xihu Bay. The evaluation results show that the comprehensive quality of the cage culture area in the Xihu Bay in 2011 was rated as ‘comparatively good’, and the main risks identified were eutrophication and the heavy metal pollution in aquatic products.

Dynamic shear modulus in marine clay containing sand was tested using RCA resonant column test system produced by GDS Company of UK. At the same time, comparing to the dynamic shear modulus in pure sand sample, the various factors such as the consolidation pressure, initial compactness, clay content, etc. influencing the maximum dynamic shear modulus of soil were studied systematically.The results show that the maximum dynamic shear modulus increases along with the effective consolidation pressure increasing and the initial density increasing, while it decreases along with the clay content increasing.

In order to find out the eco-environmental characteristics and variation trends around the Chengdao Oilfield sea areas in the Yellow River Estuary, using the methods of single factor index and comprehensive index, the monitoring data of the seawater and sedimentary quality over years were evaluated, and the changes of marine biology around the Chengdao Oilfield sea areas were also analyzed. The results showed that except for inorganic nitrogen in 2009, 2010, 2011, and phosphate in 2011, the water quality of the investigated areas reached the second-class water quality according as The Chinese National Standard of Seawater Quality. The sedimentary quality of the investigated areas reached the first-class sedimental quality according as The Chinese National Standard of Sediment Quality. The oil contents of sea water and sediment in 2006-2011 had a good corresponding relation with the annual oil production of Chengdao Oilfield. Offshore oil development caused a reduction in the total number of phytoplankton and benthic species, and the total density, biomass and community diversity index of benthos also declined. The offshore oil development caused some negative impacts on the environment around Chengdao Oilfield sea areas.

A total of 3 phyla 60 genera and 114 taxa(not including undefined species) were identified by the Utermöhl method in the survey area. The major groups were diatom and dinoflagellate. The ecotypes of most phytoplankton were temperate and coastal species. The dominant species were Dictyocha fibula, Gymnodinium sp., Gyrodinium spirale, Diploneis bombus and Paralia sulcata. The cell abundance of phytoplankton ranged from 0.037 0× 10³ to 32.3 × 10³ cells·L^-1, with an average of 2.04 × 10³ cells·L^-1. The cell abundance of phytoplankton decreased offshore. Cell abundance was highest in west region of the northern Yellow Sea, about 32.3×10³cells·L^-1, and was also relatively high in southeast region in the survey area. The vertical distribution of phytoplankton was generally decreased with the increasing of water depth, and gradually decreased from coast to offshore. The Shannon-Wiener diversity was high in the southwest survey area, and the Pielou's evenness index was high in the eastern survey area. According to canonical correspondence analysis (CCA), the main factors that influence the abundance distribution of dominant species are nutrients, and the correlation with salinity and temperature is not obvious.