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The Kuroshio on-shelf intrusion northeast of Taiwan manifests as the subsurface Kuroshio water upwelling and a "cold dome" structure in summer. Using ROMS (Regional Ocean Modeling System) model, the three-dimensional structure of the cold dome and the circulation along with upwelling induced by Kuroshio intrusion were analyzed, and the mechanisms of the formation of upwelling were also discussed. Model results show that the center of the cold dome is located near 25.5°N, 122.5°E in the layers upper of 50 m with maximum 5 ℃ cooling, and close to the north end of Taiwan Island in the layers lower of 50 m. The result of current structures show that Kuroshio surface intrusion is not obvious at the north end of Taiwan Island. A cyclonic circulation exists near the region where the shelf break turns eastward. Upwelling mainly occurs near the large slope of shelf break, with two obvious routes of the subsurface water upwelled onto the shelf. One of the routes is north of the Taiwan Island and between the isobaths of 100 m and 200 m, while the other one is near the region where the shelf break turns eastward. In the upper layer, the advection term is the main dynamical factor of the upwelling. While in the near-bottom layer, both the advection and bottom friction terms contribute to the upwelling.

High resolution shallow seismic exploration with dense grids,line intervals of mostly 120 m and 200 m, was carried out in tidal ridges and troughs area west of Taiyangshan Ridge in the South Yellow Sea. The maximum sediment penetration was about 80~90 m. Two seismic sequences(SQ1 and SQ2) were identified and further divided into five sub-sequences (U1~U5). The underlain Sequence 1(U1) consisted of land sediments of Late Pleistocene, while the upper Sequence 2(U2~U5) was mainly formed by marine sediments of Holocene. Sedimentary environments of each sub-sequence were studied based on seismic facies characteristics. Since the later period of Late Pleistocene, the study area has been mainly undergone sedimentary environment evolution of delta distributaries—river incision—paleo-river channel fill—estuary offshore—delta offshore-shallow sea —present tidal ridges and troughs. A tidal sand ridge in narrow river mouth was developed during the middle Early Holocene in the study area, but afterwards were buried due to fast sea level rise. Present tidal sand ridges were formed after the last high sea level. They did not have any inherited relationship with paleo-tidal sand ridges, nor with paleo-topography of Late Pleistocene, but were controlled by tidal current system.

Chemical composition of plagioclase phenocryst zone, plagioclase crystallite and silicate of basalts in CA Seamount (sample CAD21), was examined using EPMA method and X-Ray fluorescence spectrometry (XRF) on basis of petrography. The basalts of CA Seamount are intraplate basalts formed by the activity of mantle plume. The core and the edge of zones of plagioclase phenocrysts show nonsequence optical extinction phenomenon, indicating a discontinuous zoning structure. The sequence of zones is labradorite to bytownite from edge to core, showing a normal zoning in the process of magmatic evolution. Such a phenomenon is constrained by melt composition and temperature-pressure condition. Average temperatures of plagioclase phenocrysts are 1 281 ℃(temperature of magmatic source),1 198℃(temperature of magmatic chamber) and 1 071 ℃(temperature of magmatic exhalation) respectively. The small temperature difference indicates a rapidly eruption process, in accord with the formation and eruption characteristics of oceanic island basalt magma.

With the application of GIS technology, the hydrographic data were transformed to DEM (digital elevation model) to calculate the amount of erosion and deposition, and then the evolution process of the main geomorphic units and their mechanism were also analyzed. There were several cognitions after analyzing: (1) The tendency of the sea bed erosion-accretion process was light scour, with 27 cm rang in 72 years and at the rate of 0.375 cm/a. (2) The deep channels expanded all the time. the Wenzhou Sand Bank was kept accretion tendency, and human activities speeded up this tendency for these years. Zhongsha Sand Bank and Chongshan Sand Bank were kept scour tendency, finally linked each other and became a new Zhongsha Sand Bank in 1992. (3) Under the dynamic mechanism, the sediment movement occured between deep channels and sand banks, which was the mechanism of erosion-deposition evolution in the sea bed.

In order to research the coupling interaction among mooring dynamic positioning vessel, wharf and cables, lumped mass method was used to calculate the effective tension, and nonlinear reaction force of dock fenders was simulated by Link unit in OrcaFlex. The thrust allocation of thrusters was based on PID control system. Under mooring conditions, with the comparison the difference in horizontal degree of freedom motion and cable's effective tension between general vessel and dynamic positioning vessel, the effect of thrusters on eliminating ship movement caused by first order wave loads has been explained. According to the results of mooring DP vessel and DP vessel in the same environment load, the influence of wharf-cable and target position on side thrusters and positioning ability were discussed. The results show that the performance of the side thrusters and vessel's positioning capability can be improved effectively under the reasonable selection of target position.

A positive six prism type artificial reef was designed to improve the marine fisheries habitat of the Zhoushan Archipelago. Two parameters of ε and η were used to evaluate the structure of artificial reefs, the value ε reflects the water permeability of artificial reefs and the value η reflects the adhesion ability of artificial reefs. The positive six prism type artificial reef was found to have a good permeability, and could also provide a larger area for the attachment of marine organisms. The design objectives were met. Based on the Fluent software, the CFD simulation of the fish reef was carried out, it was found that the maximum height of the upwelling increased with the flow velocity, and the length of the back vortex was about 9.3-9.6 times of the height of the fish reef, which indicated that it had a good hydrodynamic performance. In order to validate the performance of simulation further, flume experiment was conducted, which yielded consistent results as the simulation study. This further proved the validity of the hydrodynamic performance of the positive six prism artificial reef. The field experiment was also conducted at the end to evaluate the effect of the positive six prism reefs and to compare with the regular artificial reefs. Both the reefs could improve marine environment, but the average of density and biomass in the area of the positive six prism type artificial reef was higher than those in the control reef area, showing that the positive six prism artificial reef tended to have better hydrodynamic characteristics leading to more efficient in improving local habitats.

Based on the three phase of remote sensing images of Zhoushan Island in 1995, 2005 and 2015, through the interpretation of human-computer interaction, the image of the land resources and urban land use data were obtained. And then using the ecology analysis method, spatial statistics analysis method, urban expansion index method, the Zhoushan Island reclamation activities and urban land expansion characteristics were explored, and meanwhile the association between them was also analyzed. Finally, the following conclusions were acquired: (1) The total reclamation area in Zhoushan Island was expanded from 1995 to 2015. (2) In the first ten years, land use at the beach resources was mostly in land near the beach, while it gradually went to the shallow sea in the late ten years. (3) In the years from 1995 to 2005, the growth intensity was 0.53 and the growth speed was 3.01 km²/a. In the years from 2005 to 2015, the growth intensity was 1.46 and the growth speed was 8.11 km²/a. (4) The city development center of Zhoushan Island had experienced a move from west to east and then had a northward jump process during the past 20 years. Coordinated development had been made among the various regions so that the economic integrity of Zhoushan Island and the rationality of urban functions had been upgraded. (5) The cultivation of land by tideland reclamation and urban land expansion were positively related, the research data showed that natural succession took about 8-10 years, artificial intervention could significantly shorten the process.

Using “exposure-sensitive-adaptation” model, the ecological vulnerability evaluation system of Xiangshangang Bay was established through the analysis and calculation. The vulnerability of Xiangshangang Bay ecosystem is moderate fragile, and the main stress factors are the development of harbor industry and aquaculture activities. The sensitive factors are marine biodiversity index, fish eggs and larvae density. The best adaptation strategies are to improve the environmental protection laws and regulations and management mechanism, strengthen the control of pollutants into the sea, improve the sewage treatment rate, improve citizen's environmental protection awareness and participation degree.

Tumen River is one of the most important international rivers in China. Because of the differences in the policy, economy and culture, there are many differences in the wetland landscape among Chinese, Russian and DPR Korean wetlands in Tumen River Estuary. Taking GF-1 and GF-2 images as the data sources and according to the wetland classification of national standard, the classification system of wetlands in Tumen River Estuary was set up, which included lake, river, marsh, tidal flat, pit, paddy field and reservoir. The Tumen River Estuary wetland information was extracted by visual interpretation, and then the status and differences among Chinese, Russian and DPR Korean wetlands were analyzed. By the means of Fragstats software, the landscape pattern indexes, such as NP, LPI, MPS, SHAPE, FRAC, SHDI and SHEI were used to analyze the characteristics of wetland landscape pattern in Tumen River Estuary. The results show:(1)The total area of wetlands in the study area is 39 503.38 hm², which is dominated by marsh and lake, and is presented as an aggregate distribution pattern close to the Japan Sea.(2)The wetland area of Russia is the largest, followed by those of DPR Korea and China. The disturbance is serious in that of DPR Korea.(3)The landscape fragmentation of wetland in DPR Korea is most serious, followed by those of China and Russia. Because of the serious development of paddy field, the landscape regulation degree is highest in DPR Korean wetland. The diversity of Chinese wetland is more abundant than those of other countries.

With the wave observation off the southeastern coast of Zhaitang Island from 2013 to 2014, the wave characteristics were analyzed. The statistical results show that annual average of significant wave height is 0.60 m, the maximum wave height is 5.30 m, the average period is 3.3 s, the maximum period is 8.3 s and the dominant wave direction is E-SE. The wave height distribution and the joint distribution of wave height and period were also discussed. Based on the basic spectrum structure of JONSWAP, the spectrum applied to this sea area is presented using fitting method. All the work would provide reference for wave research and engineering application in this sea area.