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Four seasonal average sea surface wind field of China offshore was obtained through ERA-Interim data from ECMWF(European Centre for Medium-Range Weather Forecasts), so that the feature of seasonal wind field variation of China offshore was figured. The result shows that China offshore is a typical East Asian monsoon region where northerly monsoon is in vogue in winter and southerly monsoon is in vogue in summer. Then the feature of China offshore's sea surface wind field anomalies was analyzed with the method of empirical orthogonal function (EOF). The merging data of multiple satellites utilized in this study is from NCDC(National Climatic Data Center), which has been collected since Sept. 1987. Some results can be obtained by analyzing 313 monthly average data. The first mode of China offshore's sea surface wind field anomalies makes contribution to 63.94% of the total variance. This mode shows the seasonal variations of China offshore, which means that the type of feature is winter-summer monsoon oscillation. The second mode makes contribution to 12.35% of the total variance, which reflects the feature of sea surface wind field during the transition period of winter monsoon and summer monsoon, so it shows the type of spring-autumn oscillation. The third mode, contributed to 3.49% of the total variance, which shows fluctuation with an approximative period of half-year, reflects intraseasonal variation of sea surface wind field variation.

Based on WOD09 and Argo data of twenty seven years(1984-2010), and combined with SODA、OFES、GPCP and WHOI data, the long-term trends and interdecadal variability of mixed layer salinity at the western Luzon Strait were analyzed. The results can be described as follows: (1)the salinity decreased about-0.020 per year from 1984 to 2010; (2)because of the variability of Kuroshio meridianal flux, the Kuroshio invasion was weakened after 1999, which resulted in the salinity being positive anomaly before 1999, with a maximum of 0.14 and a mean of 0.05, while negative anomaly after 1999, with a minimum of -0.22 and a mean of -0.06; (3)by calculating the salinity budget, the variability of salinity at the western Luzon Strait is controlled by advection primarily.

The best track data of tropical cyclones (TC) for 62 years (1951-2012) obtained from Japan Meteorological Agency (JMA) were used to make an analysis on the temporal and spatial distribution of two kinds of tropical cyclones, i. e. entitled local typhoon and non-local typhoon which have impact on the South China Sea (SCS). The result suggests that local typhoon’s sources are associated with the monsoon period. In summer monsoon, the sources mainly located on the north of 15°N, and in winter monsoon, it moved to the south of 15°N. Compared with non-local typhoon, local typhoon’s activity is broader in space, but weaker in intensity in commonly. In the intensity development process, the time-intensisy curve of local typhoon is almost symmetrical, but that of non-local typhoon is a decline curve. The two kinds of TC’s landing positions are also associated with the monsoon. In summer monsoon, local typhoon and non-local typhoon make landfall more frequently than those in winter monsoon. And in the same latitude, non-local typhoon moves faster than local typhoon.

There are extreme gusts and waves when the developing extratropical cyclones (DECS) enters the Zhejiang coastal waters, which can bring about shipwrecks and fatalities. In this study, the Weather Research and Forecasting (WRF) model system which is typically used in the regional meso-scale model prediction, was used to simulate a DECS process. Three experiments were conducted: experiment one (without assimilation data); experiment two (with assimilation of cloud drift wind data (CDWD), quality control was not conducted to the CDWD) and experiment three (with assimilation of CDWD, quality control was conducted to the CDWD). The comparison of the three experiments shows that including the assimilation of CDWD, they can have positive impact on DECS prediction. The results of experiment three are very similar to those of actual observation, therefore it can improve the prediction accuracy about the DECS which influence the Zhejiang coastal waters.

The supported vector machine was adopted on the coastal wetland land cover classification using fused images of 4-polarization SAR and TM images, the results of classification were compared and evaluated to analyze the capability of different-polarization SAR and TM fused images in coastal wetland area. An area of Yellow River Delta was selected as the experimental area, and a Radarsat-2 full-polarization image and a Landsat-5 TM image were taken as an example. The results of the experiment were analyzed quantitatively, which show that the classification accuracy of the original TM image can be improved by using the SAR-image-fusion method, the classification accuracy of the image fused by the HV-polarization SAR and TM image is the highest, so that the HV polarization is the most suitable polarization of SAR image for fusion and classification research work in coastal wetland area.

With the population increasing, the boom of industry and city, the policy stimulation, as well as the rise of external trade, shoreline changes accelerated in the Fangcheng Bay. Using Landsat data of 1973, 1979, 1990, 2000 and HJ-1B data of 2010, shoreline changes of the Fangcheng Bay during past 40 years were analyzed. The results show that the shoreline of the Fangcheng Bay kept expanding seaward constantly from 1973 to 2010, resulted in the land area increased by 4 216.61 hm², while the shoreline length decrease by 36.96 km, which was mainly induced by anthropogenic factors. As for the decreased shoreline, the muddy shoreline occupied mostly and the rocky shoreline occupied secondly. Based on the regional character of the Fangcheng Bay, the study area was divided into three parts: the Fangchengjiangkou coast, the Anbukoujiang coast and the Yuwan Island. The rocky shoreline along the Fangchengjiangkou changed slightly from 1973 to 2010, with an increase near the Fangcheng River Estuary of only 74.58 hm². Since the shoreline along Anbukoujiang is muddy, it has kept expanding seaward during past 40 years, therefore, many flexuous bays were filled. The shoreline of Yuwan Island changed the most dramatically. There's a 2 027.41 hm² increase of land area and a 2.46 km decrease of shoreline length. The remote sensing image of Yuwan Island indicates that it had united with the continent in 1990. The fractal dimension shows that the shoreline becomes straighter.

Based on the main beache quality evaluation systems at home and abroad and combined with the actual situation of island beaches in Zhejiang Province,a suitable quality evaluation system was constructed for Zhejiang Province. The system has 29 factors in number, including 3 large classes and 7 subclasses, which was used to evaluate 63 island beaches in Zhejiang. The result shows that the overall quality of the beach at the middle level, as there are 7 five-star beaches,19 four-star beaches,29 three-star and 8 two-star beaches, which indicates that the evaluation system has better applicability.

The geochemical characteristics of hydrothermal deposits and basalt samples taken from the ultraslow-spreading Southwest Indian Ridge at 49.6°E were analyzed by using XRF and ICP-MS. The results indicate: (1) the basalt samples in this area tend to be more alkaline comparing with the contents of the major elements of the N-type mid-ocean ridge basalts (N-MORB), and they are richer in Pb element than the N-MORB comparing with the contents of the trace element; (2) the analysis of major elements and trace elements of hydrothermal deposits indicates that the chosen samples are mostly Fe, Si, Mn-rich oxyhydroxide, and both of them are the hydrothermal origin; and (3) the contents of REE in the hydrothermal deposits are between those in basalt and seawater, the chondrite-normalized REE patterns of the hydrothermal deposits are characterized by positive Eu anomalies and LREE enrichments, and the geochemical indicators can not only simulate the distribution of element halos center on the hydrothermal vent on a small scale, but also reflect the influence area of the nearest hydrothermal activity.

According to the monitoring data over consecutive years for the seabed where submarine pipeline is from Cezi Island to Zhenhai, the results indicate seriously scouring phenomenon. For the purpose of making analysis about human activity influence, a two-dimensional numerical model was set up to simulate hydrodynamics and sediment environment of the Hangzhou Bay with Delft3D. This model had been calibrated and validated with observed data of tidal level, currents and suspended sediment concentration. The results show that the reclamation in Xinhongkou of Zhenhai and Jintang Bridge have a great impact on the seabed scouring of the landing position in Zhenhai. The results also show that the water-blocking effect of Jintang Bridge could aggravate the seabed scouring of the slope position in scouring channels, and that the seabed scouring of the extension position in deep pools is closely related with the main navigable hole of Jintang Bridge.

Major elements (SiO₂, Al₂O₃, Fe₂O₃, MgO, CaO, Na₂O, K₂O, P₂O₅, TiO₂, MnO, TOC and CaCO₃) of 187 surface sediments from Changjiang River Estuary have been tested to analyze the spatial distribution character and geological significance. The results indicate that the major element oxides are mainly composed of SiO₂, Al₂O₃, Fe₂O₃, MgO, CaO, Na₂O, K₂O and TiO₂, which account for 91.59%. SiO₂ has the highest content in this area with the average content up to 62.43% . Al₂O₃ has the second highest content of 11.16%. R-factor analysis indicates that the major element oxides of surface sediments can be classified into three groups: the first group includes SiO₂, Al₂O₃, Fe₂O₃, MgO, P₂O₅, TiO₂ and MnO; the second group includes CaO, K₂O, CaCO₃ and TOC and the third one includes Na₂O, which possibly represent the terrigenous sediment, the mixture of marine biologic sediment and terrigenous sediment, as well as the marine chemical sediment. Similar spatial distribution of Al₂O₃/Na₂O and CIA indicates that the materials are mainly derived from Changjiang River and accumulated in the estuary and its southern area, especially in the west of 123.5°E area. The main driving force is Min-Zhe Coastal Current in the study area.

Halophilic and halotolerant bacteria were isolated by media HM and ZMCA from seawater of ten sampling stations of the Changjiang River Estuary. Totally 156 16S rDNA sequences were obtained, of which 136 sequences were obtained from bacteria isolated by medium HM and the others from medium ZMCA. The bacteria from medium HM could be classified into 33 OUTs and they belonged to genus Oceanicola, Sagittula, Aurantimonas and Stappia within the class α-Proteobacteria; genus Alteromonas, Marinobacter and Pseudoalteromonas within the class γ-Proteobacteria and genus Bacillus, Gracilibacillus, Oceanobacillus, Halobacillus as well as Thalassobacillus within the class Bacilli of phylum Firmicutes. Strains isolated from stations M5-1, N6-2 and M4-1 which close to mainland were all belonged to Firmicutes, while strains isolated from stations far from mainland were all belonged to Proteobacteria. The bacteria isolated from medium ZMCA could be classified into 10 OUTs and they belonged to α-Proteobacteria and Actinobacteria. About 70.5% of the 136 strains isolated from medium HM could grow without NaCl and be classified as halotolerant bacteria. About 25.9% of the strains isolated from medium HM could grow in medium containing 0.5% NaCl but no growth was observed without NaCl and could be classified as moderately halophilic bacteria. While for the other 3.59% strains isolated from medium HM, no growth was observed in medium containing 0% or 0.5% NaCl, but growth was observed in media with 10% NaCl, which also could be classified as moderately halophilic bacteria. All strains isolated from medium ZMCA could grow without NaCl and be classified as halotolerant bacteria. 30.3% of strains isolated from medium HM could reduce nitrate, while only 9.9% of the strains could reduce nitrite.

Based on the data obtained from the observation from July 2006 to December 2007, The SiO₃-Si dilution and its relationship with environmental factors in surface water around the Changjiang River Estuary were primarily analysed. Field investigation showed: (1)SiO₃-Si concentration in surface water around the Changjiang River Estuary had a good correlation with salinity in autumn and winter, which was mainly affected by physical mixed effect. There were some differences in spring and summer, which was mainly affected by biological effect, suspended particle matter and sediment. (2)In the surface water around the Changjiang River Estuary and adjacent area with salinity from 0 to 18, SiO₃-Si concentration slightly increased with temperature increasing, which was mainly affected by suspended particle matter and sediment. SiO₃-Si concentration basically unchanged with pH from 7.7 to 7.9, but decreased with pH from 7.9 to 8.2, which was mainly affected by physical mixed effect. SiO₃-Si concentration basically unchanged when DO changed. (3)In the surface water around the Changjiang River Estuary and adjacent area with salinity from 18 to 33, SiO₃-Si concentration was high in the Changjiang River Estuary and Hangzhou Bay, but was under 20 μmol/L in other area. Since the SiO₃-Si concentration was mainly affected by biological and physical mixed in spring and summer, physical mixed in autumn and winter, it decreased with pH from 7.9 to 8.3. Also the same reason, a negative correlation between SiO₃-Si concentration and DO in spring and summer while a positive correlation in autumn and winter were appeared.