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Argo data have become an important data source in basic researches of ocean and atmosphere sciences. But with the hybrid storage of profile metadata and its observations, it is difficult for existing shared platforms to realize the real-time visualizing of the drift trajectory and profile chart. A method of collaborative management of structured and semi-structured Argo data were proposed. Based on the analysis of Argo data structure and characteristics, Argo data were separated as structured and semi-structured data. By means of extended support of relational database to a semi-structured property, a relationship between profile metadata and observation data was established. Faced of the rapid growth of data, a multi-table storage method was used to reduce storage pressure of single data table. Finally, an Argo database was set up and global Argo data in period of 1997-2016 are parsed and imported. The results indicate that the method has good scalability of both storage and query, as well as high efficiency of float trajectory query, and it is able to support real-time visualization of float trajectory and profile chart. Our result will offer a reference for management of other similar observation profile data.

A key factor of numerical typhoon prediction models is the initial field. COSMIC(Constellation Observation System of Meteorology, Ionosphere and Climate) satellite data assimilation was used to improve the initial condition, and its effect on improving tropical storms(or typhoon) prediction was evaluated. Employing the GRAPES(Global/Regional Assimilation and Prediction System)which was developed independently by China, typhoon Usagi(1319) was simulated. Analyses are made based on the various outputs, such as temperature, humidity, vorticity, divergence and pseudo-equivalent temperature. The results show that COSMIC data, comparing to the radiosonde data, can enhance the ability of typhoon path and precipitation forecast assimilation. So this research indicates that assimilation of satellite data contributes to the improvement of GRAPES model as well as provides an example on preventing typhoon disasters and reducing damages.

Airborne LiDAR sounding technology is considered to be a promising new technique for earth observation. In China, most of the LiDAR sounding experiments were conducted in areas with relatively clear water quality, such as the South China Sea. This is the first time to introduce the advanced CZMIL(Coastal Zone Mapping and Imaging LiDAR) system in China. The Luoma Lake in Jiangsu Province was selected for experimental area. The test results show that although the survey area has low bottom reflectivity and high bottom reflection diffuse attenuation coefficient, CZMIL system can successfully detect the bottom data. The accuracy of result can meet the accuracy requirement of CZMIL system. The CZMIL system has better detection ability and precision.

According to the principle of remote sensing water depth inversion, WorldView-2 multi-spectral satellite data and chart depth data of Longwan Port in Hainan Island were used. The water depths in 0-2 m, 2-5 m, 5-10 m, 10-15 m and 15-20 m were partitively treated, tidal correction,the correlation analysis and regression analysis of chart water depth and the corresponding image band reflectivity values were also developed, and a piecewise linear model was built for shallow water bathymetry with which the actual calculation of shallow water depth and precision analysis were carried out. The results show that the depth accuracy of the partitioned linear regression model is higher than that of the non-partitioned model in different water depth ranges. In the partition model, the multi-band model has the highest inversion accuracy of 0-5 m, and the double-band ratio model has the highest inversion accuracy of 5-20 m, but inversion of the depth in the most shallow yet to be improved. The water depth extracted by this method is similar to that of chart water depth data, which can meet the requirements of marine scientific research on large-scale shallow underwater detection requirements.

Reflection feature and seismic event continuity appeared in 3D seismic acquisition data was cluttered and poor in one study region of the Laizhou Bay. The sparker investigation was carried out in shallow strata and two geological borings were drilled in the abnormal and normal region respectively, at the same time, the strata were sampled entirely from 0 m to 150 m below the seabed. Through comprehensive comparison and analysis of the geophysical data and geotechnical data, it is clear that anomalous seismic reflection in shallow strata of the study region relates to various influence factors below: (1) The study region is in the eastern Laizhou Bay Sag strike-slip zone, and therefore many small faults which were affected by the fault system were developed in the shallow strata.(2) An amount of shallow gas was revealed in the shallow strata.(3) Comparing with the shallow strata of nearby region, the soil characteristic was anomalous in the study region; the soil strength and shear wave velocity were significantly larger.

Estuary is a transitional area from river to sea, which represent an environment with complex essential factors, so they are highly different from each other in terms of the patterns of temporal and spatial variability of the processes. Generally, there are many parameters to define the boundary between the river and the sea. The relationship among the demarcation methods based on the geometric and geomorphologic character and other estuarine parameters was analyzed. For each of these, a geomorphic node may be the most suitable method to determine the location of boundary. At a point on the river centerline, a function of B=f(L) was defined, where B is the channel width at this point and L is the distance from this point to the entrance of estuary along the central axis of the river. By constructing a mapping function, the geomorphic node can be found and the quantitative segmentation of the boundary between the river and the sea can be realized. For different kind of estuaries, the B-L curve was constructed to defined the river-sea boundary based on the geomorphic node. The result show that for the blocked estuary the rates of river width variation at the geomorphic node are -0.5 to 0. For the channel-form estuary and interconnected estuary, the rates of river width variation at the geomorphic node are 0.5 to 1.2. For the firth estuary,the rates of river width variation at the geomorphic node are 0.6 to 1.5. For the funnel-shaped delta, the rates of river width variation at the geomorphic node are 1.3 to 4.5. For the bird-foot delta and fan delta,the rates of river width variation are always 0 to 0.2, and the entrance of estuary is regarded as geomorphic node. This B-L curve is applied to measure and calculate the length of estuary shoreline of China mainland, and some perfect results are acquired.

Surface zooplankton samples were collected between 21°S and 38°S during the Dayang-1 scientific cruise in Southwest Indian Ocean in summer of 2013. By using zooplankton community structure analysis and clustering method, the distribution pattern of community structure and biodiversity of this region were explored. The results showed that the zooplankton species belonged to 69 species of 50 genus, including copepods, euphausiids, amphipods, decapods, ostracods, chaetognaths, tunicates, heteropods, pteropods, cnidarians, polychaetes and etc. In terms of abundance, copepods and euphausiids accounted for the largest percentages (69% and 27%, respectively). The variation of H′, D, J biodiversity indices with the latitude accorded a linear trend, i.e. most biodiversity indices decreased with the increase of latitude. In contrast, a binomial relationship was found between the biodiversity indices and longitude. Most biodiversity indices increased with the longitude. The clustering results showed that northern and southern zones could be distinguished by the latitude boundary around 36°S, with the predominant species of copepods (small particle) in northern zone and euphausiids (large particle) in southern zone respectively. Moreover, the similarity of species composition indicated that the spatial connectivity of zooplankton communities was week between the southern zone and Crocker Strait or Great Wall Bay in Antarctica, as well as between the northern zone and Northwest Indian Ocean.

Size-fractionated chlorophyll a concentration (Chl a) and primary production (PP) of phytoplankton in the northern South China Sea (nSCS) were investigated during the winter of 2009. The results showed that Chl a and PP had obviously spatial variation in the nSCS. The water column integrated average values of Chl a varied from 0.11 to 8.37 mg/m³, the average value was (1.28±2.23) mg/m³, and decreased from the coastal zone to the open sea. The lowest and highest value of PP were 344.8 mgC/(m²·d) and 1 222.5 mgC/(m²·d), respectively, with the high value appearing in the coastal zone and continental shelf. The result of size-fractionated Chl a showed that microplankton (Net-Chl a) was greater contributor (about 40.9%) to phytoplankton stocks in the eutrophic coastal zone and the proportions of nanoplankton (Nano-Chl a) and picoplankton (Pico-Chl a) were 34.6% and 24.5%; while in the oligotrophic continental shelf and open sea, the contributions of three size-fractionated Chl a from greatest to least in order were Pico-Chl a (78.9%), Nano-Chl a (17.2%) and Net-Chl a (3.9%). Relevant analysis results showed that the regional distributions of Chl a were closely related to the nutrient dynamics driven by the ocean currents; meanwhile the distributions of Chl a drastically affected the distributions of PP as well. Furthermore, compared P^B_opt in situ with that estimated by the depth-resolved model for carbon fixation (VGPM), it was found that the later were less than the former obviously, and this indicated that the underestimated value of P^B_opt through temperature might be exited in nSCS.

The temporal and spatial distribution of seawater transparency was analyzed according to the marine monitoring data of Qingdao coastal area in 2014. Multiple linear regression analysis was utilized to find out seven key environmental factors as the independent variables, and an optimal multiple linear regression statistical model was established. In addition, the single-factor correlation analysis and curve fitting analysis were also utilized to further prove that the seawater transparency was significantly correlated with the content of chlorophyll a, suspended matter and water depth, and the curve fitting equation is drawn.

To understand the diversity of bacteria during the seedling stage of Apostichopusjaponcicus, bacteria were isolated and identified. On the basis of the morphology, physiology and biochemistry, 16S rDNA sequence homology analysis, the 19 marine bacteria were identified to be Brevibacillus sp., Pseudoalteromonas sp., Cobetia sp., Enterobacter sp., Bacillus sp., Providenciasp., and Oceanospirillaceae sp.. Isolation and screening of bacteria from the marine environment is of great significance to the development and utilization of marine resources. In addition, the identification of the bacterial species in the period of seedling stage of Apostichopusjaponcicus is helpful to the prevention and treatment of disease, and it has a certain guiding significance for the aquaculture of Apostichopusjaponcicus.

Three-dimensional mathematical model of scour around Trawl Resistant Seabed Basement on sand bed was established using Flow-3D. By changing the flow velocity and sediment particle size, the scour on sand bed under different conditions was simulated, and the changes in the trend of maximum scour depth around Trawl Resistant Seabed Basement with the two factors was analyzed. The results show that the scour depth around Trawl Resistant Seabed Basement is increased with current velocity increases, under the other setting conditions unchanged, the scour pit deepened velocity with increasing flow velocity is gradually slowed down, and ultimately achieved sedimentation balance. At the same time, due to the complex and changeable seabed environment, the model and the actual situation are different, and therefore further research should be continued.