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Variational assimilation technique, in conjunction with the ship reported data, is applied to a short term numerical prediction model in order to realize automatic short term SST forecast in the Bohai, the Yellow and the East China Seas. The prediction model, using the adjoint assimilation method, achieves a global optimization of the initial SST field. Corresponding to the four typical months (February, May, August and November) of four quarters respectively in 2002, we do forecast for a month continuously. The results indicate that the root mean square error between the hindcasts of 24 successive hours and the ship reported data is reduced to below 0.8 ℃. The mean absolute errors of SST are reduced markedly, compared with the values before assimilation. The forecast accuracy is improved with the adjoint assimilation method compared with the results from the objective analysis method.

The sea surface wind speed has a important impact on the navigation, ocean engineering and disaster prevision. In this paper, the observed wind data from Taiwan Island and South Korean was used to verify the validation of the T639 wind production during the typhoon “Fitow” and a cold air process. Results show that: (1) During the typhoon “Fitow”, there is a good consistency between the forecasting wind speed and the observed wind speed. (2) From the correlation coefficient, there is also a close relationship between the forecasting wind speed and the observed wind speed. About the Bias error, the forecasting value is slightly larger than the observed value. Comprehensive consideration of the root mean square error and mean absolute error, the precision of the T639 wind production is high. (3) During the typhoon “Fitow”, the T639 wind production can describe the characteristics of typhoon (including the typhoon eye and typhoon end mark) very well. The Waipu meteorology station, Dongjidao meteorology station and Lanyu meteorology station were effected by the typhoon noticeable but the Danshui meteorology station, Jinmen meteorology station and Lvdao meteorology station. The T639 wind production can also describe the cold air process very well.

The Ross Sea is located on the Pacific side of the Antarctica. Based on analysis of sedimentary, structural and temperature-pressure conditions,it is proved that Rose Sea has good conditions for the reservation and exploration prospects of gas hydrates. In this paper,the heat flow data are used to calculate the thickness of the gas hydrate stability zone. An integral method is conducted to estimate the amount of gas hydrate resources in this region. The results show that the amount of gas hydrate resources of Ross Sea region is 3.6×10¹¹ m³, which means considerable economic value.

In this study, the U^k₃₇ indices for surface sediment samples derived from the South China Sea (SCS), Pacific Ocean, East China Sea (ECS) and Arctic Ocean are analysed, as well as the overlying averaged sea surface temperature (SST) at 0~30 m depth. The alkenone-derived U^k₃₇ index is justified as a useful palaeoenvironment proxy at extreme cold and warm end (-0.6 ℃~28 ℃) because the resulting U^k₃₇ indices show a significant correlated linear relationship with annual averaged SST. Simultaneously, U^k₃₇ indices have been correlated with averaged SST of four seasons in the SCS as well. However, the seasonal pattern of Coccolith (E. huxleyi and G. oceanic), being source of alkenone, is showed prosperous in winter time. As a result, the sedimentary U^k₃₇ index may only reflect the winter SST of the overlying waters.

As Digital elevation model is an important geographic information, SAR(synthetic aperture radar) is one of the most effective means in digital elevation model extracting. Use Radarsat-2 fine Quad-polarization mode data (November 27, 2013)over Qushandao in Zhejiang province to figure out the polarization azimuth offset between two adjacent resolution cells, and then extract the gradient information and terrain elevation. Finally, test the accuracy of the digital elevation model by the measured data, whose average relative error turn out to be 20%,and the results showed that the main causes of errors is the change of the terrain basement caused by the sea clutter and the elevation deviation caused by the leaves and boughs of the vegetative cover.

In order to study the influence of the formation of biofilm on the corrosion of DH32 structural steel, the growth curve of a marine microorganism (Vibrio natriegens) was tested by UV-Vis spectra, the formation process of biofilm and the surface of the coupons were characterized by scanning electron microscope and atomic force microscope, respectively. The results show that the formation of biofilm closely associates with the growth of bacteria, the formation process of biofilm changes the chemical and physical state of the steel surface. Moreover, the formation of oxygen concentration cell and binding power of extracellular polymeric substances with metal ions greatly promotes the DH32 surface oxidation corrosion.

In this study, a data sample has been established including 13 sorts of water quality index and 400 stations of hypothesis sampling according to the <National Water Quality Standard (NWQS)> for the evaluation model of coastal water quality. By calculating the KMO, sphericity test as well as the correlation matrix of all indices, we found that there was a good correlation among indexes, which indicated that the principal component analysis (PCA) could be applied to extract information. For 13 indexes of water quality, only the first two principal components with eigenvalues ??greater than 1 are effective, which could represent 81.25% information of the samples, as a result, a quality automatic classification layout (evaluation model) which could accurately classify four kinds of waters has been set up. A thematic map of water quality classification in the coastal waters of Leizhou Peninsula in 2010 was drawn according to the water quality automatic evaluation method. In this map, case IV waters were in the Zhanjiang harbor, Jianjiang Estuary and Tieshan harbor sea area, and case III waters were mainly in the southwest of Donghai Island, offshore area of Jianjiang estuary, northeast of Xuwen, Liusha Bay and Jianghong harbor sea areas, and on the other sea area of Leizhou Peninsula, they were case I and II waters in 2010. This study provides a better distribution in water quality environment of the coastal waters of Leizhou Peninsula, which offers some references for the comprehensive treatment and utilization in this area.

The national nature reserve of Shuangtai River Estuary is located in the lower reaches of Liaohe River Estuary, there are many wetlands in the region, the land use/cover types of which are various. The author analysed the land use and land cover (LUCC) and their driving forces in the national nature reserve of Shuangtai River Estuary from 1984 to 2013 by utilizing the Landsat TM, ETM, OLI-TIRS remote-sensing images of 5 different periods in the past 30 years. The method which combines GIS spatial analysis with mathematical statistics was adopted. The results show that the marsh reeds area and aquaculture area increased widely, the natural water area and beachland area diminished widely, the single land use dynamics of aquaculture area was the largest during 1984 to 1992. The farmland area and beachland area increased fast, the natural water area and marsh reeds diminished fast, the comprehensive land use dynamics was the largest during 1992 to 2000. The aquaculture area increased widely during 2000 to 2007. The construction land increased widely during 2007 to 2013. The LUCC of the national nature reserve of Shuangtai River Estuary was influenced by many factors and population, economy, policy were the mainly social economic factors.The performance of each factors were different during different periods.

Coastal landscape is the foundation of sustainable social and economic development in coastal areas .It is significant to make a analysis change of landscape ecological risk on coastal zone to optimize the evolution of the coastal landscape planning and rational development of landscape resources. The study, based on the Landsat TM/ETM+ remote sensing data of 1990-2010 and field survey ,analyzes the temporal-spatial change of landscape ecological risk on coastal zone of Xiangshangang bay. The results show that: (1) Over 20 years, Great changes of landscape patterns have taken place in Xiangshangang bay . The area of arable, sea, woodland decreased. While the area of construction land, unused land and farming land increased. (2) Since 1990, Xiangshangang coastal landscape ecological risk grade has constantly increasing trend. Some low, low grade of ecological risk area evolved in high grade and extremely high grade.(3) Judging from different levels of ecological risk from space area distribution ,It embodies in the space that the extremely low and low grade ecological risk areas shrink to upstream during 1990~2010, and the area show a downward trend. The medium, high and extremely high grade ecological risk areas expand to the coastal areas. In terms of the evolutionary rate, nearly 10 years of high and extremely high ecological risk area has significantly accelerated the rate of increase over the previous 10 years.

We propose a new method for tidal energy utilization using water-hammer in pipeline. The hydro-ram can convert potential energy of low water head to higher head by pumping sea water to high reservoir,which avoid the energy conversion from tidal power to pumped storage. Model pump test was carried out to simulate the 1~3 m working condition of pumping sea water to 5~20 m high reservoir. We got the efficiency and output power of several supply head in the test. The experiment shows that the efficiency can be higher than 60% in the working condition and remain stable when water level changes.

Based on the survey in Sanmen Bay in May 2013, a preliminary research on the net-phytoplankton community characteristics was carried out. The results show that a total of 9 phyla' 253 species are found in the survey area, and the community is mainly composed of Bacillariophyta (71.5%), followed by Dinophyta (16.6%), and other phyla occupies low ratio. The average value of cell abundance is (2 227±3 883)×10³个/m³, and the highest value appeares in the northeastern area near the mouth of the bay (EMB). The dominant species are Eucampia zodiacus, Biddulphia sinensis, Chaetoceros castracanei, Coscinodiscus concinnus, Skeletonema costatum, Coscinodiscus jonesianus and Nitzschia sigma. Because the effect of water temperature, salinity or other environmental factors, the dominants distribution demonstrates spatial difference among the mouth, the middle and the top of the bay. Besides, comparing with the historical data, it is found that the phytoplankton cell abundance increases and the diatom species declines in percentage of the total species.

According to the investigation results of Dongshan Bay and its adjacent sea area in May and August 2011, DIN、DSi、SRP、TN、TP、COD、DOC、TOC、Chl-a and total abundance of phytoplankton associated with eutrophication were analyzed with principal component analysis(PCA).Three principal components (PCs) were extracted with principal component analysis: phytoplankton、TP and COD for PC1, N nutrients and silicon nutrients for PC2 and P nutrients for PC3. Distribution of PC1、PC2、PC3 and CPC in spring and summer show the high eutrophication risk regions, where were Zhangjiang Estuary and Bachimen adjacent areas. The correlation analysis with salinity showed that eutrophication pressure was mainly from Zhangjiang in Dongshan Bay, and enhanced in summer. COD and phytoplankton are dominating factors in assessing the variation of eutrophication in Dongshan Bay and its adjacent area.