A Finite Volume Coastal Ocean Model (FVCOM) that assimilated tidal gauge data was used to study the tidal energy flux and dissipation in the Northwest Pacific, including the China seas, the Japan Sea (JS) and the Sea of Okhotsk (SO). Most of the tidal energy in the Northwest Pacific is transmitted to the East China Sea (ECS), the South China Sea (SCS)and the SO. The semi-diurnal tidal energy transported into the ECS is three times larger than that transported into the SCS; whilst the diurnal tidal energy transported into the SCS is five times of that transported into the ECS. In the waters east of China, 64.3% of M₂ semi-diurnal tidal energy is dissipated in the ECS,32.4% in the Yellow Sea (YS), and only 3.2% in the Bohai Sea (BS). For K₁ diurnal tide, 48.2%, 31.4% and 7.1% of the tidal energy are dissipated in the ECS, the YS and the BS, respectively. Among the tidal energy transported into the SCS, 32.7% of M₂ and 38.3% of K₁ are dissipated in the northern region, 23.9% of M₂ is transported into and dissipated in the Taiwan Strait, and the rest enters the southern SCS. Little tidal energy is transported from the Pacific Ocean into the JS. The dissipation of diurnal tidal energy in the SO doubles that of the semi-diurnal tidal energy.

A mooring system was placed at a depth of about 3300 m west of the Luzon Strait. Upper ocean current, temperature and salinity were measured at a high frequency for more than nine months. Using harmonic analysis and power spectral analysis, we discover that at the measuring site, O₁ tides had a greater amplitude in spring, and K₁ tides had a greater amplitude in winter. In summer, the internal tides were relatively weak, but there were always irregular diurnal tides at our observation site. We observed near-inertial oscillations at a depth of 200~270 m after Typhoon Nanmadol passed by; they rotated clockwise and the energy was transported downward. There were 105 internal solitary waves (solitons) passed by during our observation period, while there were no less internal solitary waves in winter than in spring and summer. The arrival times of two adjacent internal solitary waves differed by about 24.6~24.7 h, which cannot be divided into type-a waves or type-b waves.

Based on gridded Argo data during 2005~2009 provided by the Real-time Argo Data Center in China, the surface and deep ocean temperature of the ocean east of Taiwan are investigated. The results show that the North Pacific Subtropical Mode Water exists south of Japan. The authors put forward an idea of constant warm mode water, revealed its cause and vertical structure, and confirm it with SODA (Simple Ocean Data Assimilation) and WOA09 (World Ocean Atlas 2005) data. It can be concluded that there are three kinds of mode in different layers of the ocean east of Taiwan. Thus, the ocean east of Taiwan can be divided into three areas: tropical area, subtropical area and temperate area. By analyzing the thermocline of each area using thermocline profiles, permanent and seasonal thermoclines’ vertical distributions and seasonal variability are summarized. They authors provided explanations to these results.

Seasonal variation of the surface-layer circulation in the eastern tropical Indian Ocean (ETIO) is analyzed using nearly 20 years of surface absolute dynamic topography (ADT) data derived from satellite observations, ocean surface current analysis-realtime (OSCAR) data and the trajectories of Argos surface drifters. The results show that the seasonal variations of the surface circulation and the monsoons in the ETIO are almost coinstantaneous. The seasonal variations are more significant north of the equator. With this seasonal cycle of large-scale circulation, the circulation at the mouth of the Bay of Bengal changes accordingly. During May-September, the eastern mouth of the bay is dominated by the southward meridional current, which extends further southward off Sumatra, while it reverses to flow northward during the rest months. The meridional current in the western bay mouth is generally opposite to that in the east. The Argos drifting buoy trajectories further reveal that the water exchange pathways in and out the bay change seasonally. During the summer monsoon, the drifting buoys from the southern India Ocean and the Arabian Sea are mainly drifted into the bay from the west side of the bay mouth, while those from the bay are drifted out from the east side. The pathway reverses during the winter monsoon. This study also shows that the maximum variance of the zonal currents is caused by the monsoon currents including the Wyrtki Jet, while the maximum variance of the meridional currents is due to the East Indian Coastal Current (EICC) and Lakshadweep High (Lakshadweep Low).

Based on the NCEP/NCAR reanalysis data and the sea surface temperature (SST) data from the NOAA, the influence of SST anomalies (SSTAs) associated with the ENSO and IOD (Indian Ocean Dipole) events on low-level anomalous anticyclone in the Philippine Sea (named PSAC) was investigated using diagnosis methods and simulation experiments. The results are as follows. There is a more significant relationship between the IOD events in preceding autumn and the PSAC from winter to spring than that between other Indian SSTA events and PSAC. In a pure El Niño year, there is a notable PSAC appearing over the Philippine Sea from November to the following April. Compared to the El Niño events, the influence of pure positive IOD events on the PSAC is much weaker based on the reanalysis data and has shorter lifecycle from November to the following April. In the co-occurring year of El Niño and IOD, the PSAC tends to enhance and remain until the following August, which indicates that these SSTA events reinforce the PSAC jointly.

In this study, the Advanced Television and Infrared Observation Satellite Operational Vertical Sounder (ATOVS) radiance (including AMSUA, AMSUB and HIRS) was assimilated into the Weather Research and Forecasting (WRF) model to improve track simulation of Typhoon Megi (2010) and Typhoon Nesat (2011) using the three-dimensional variational (3DVAR) approach. The results from a series of assimilation experiments are as follows. 1) The assimilation of the radiance data can improve the accuracy of typhoon track simulation through adjusting the initial fields of typhoon structure including the atmospheric circulation, temperature and moisture. 2) Different satellite radiance data have different effects on improving typhoon track simulation. The improvement by AMSUA data is obviously greater than that by AMSUB data or HIRS3 data. 3) The assimilation of satellite radiance data can significantly influence the environmental steering flow through changing the strength and location of the subtropical high, leading to the improvement of typhoon track simulation.

A total of 224 surface sediment samples collected from the northern South China Sea were studied in terms of grain size and carbonate content, to understand the sediment transport patterns and the corresponding depositional environments in the region. Results revealed that sediments in the study area could be divided into the following types: gravelly sand, coarse sand, medium sand, fine sand, silty sand, sandy silt, sand-silt-clay, clayey silt, silty clay, and clay. The abyssal-bathyal sediments could be divided into eight types, namely, siliceous clay, calcareous clay, calcareous and siliceous clay, foraminifer ooze, calcareous clayey silt, calcareous sand-silt-clay, and siliceous clayey silt. Among them, the silty clay, clayey silt, sand, sandy silt, and clay are the major types, accounting for more than 80% of the area total. Factor analysis of grain size parameters and carbonate content was used to discriminate different depositional environments. Results showed that the above parameters may be divided into three types and the study area could then be divided into four subareas. The factor 1 acts on subareasⅠand Ⅱ. Clayey sediments are distributed in subarea Ⅰ, which is mainly located in the deep waters in the southeast. The medium and fine sand zones are distributed in subarea Ⅱ, which normally occurs on the outer continental shelf off the west of Guangdong Province and the offshore area along the coast of South China. The factor 2 acts on subarea Ⅲ, where silt of coarse and medium sizes is mainly distributed on the slope in the southeast off Hainan island and off the Pearl River Estuary, and on the outer shelf southwest off Taiwan. The factor 3 acts on subarea Ⅳ, where coarse sand is mainly distributed on the inner continental shelf southwest of Taiwan.

Using flexural backstripping and gravity anomaly modeling techniques and Process-Oriented Gravity Modelling (POGM), we calculated variable effective elastic thickness (T_e) of a long cable, multi-channel seismic reflection profile across the northern margin of the South China Sea and analyzed the lithospheric strength distribution during rifting and post rifting. Results show that the lithospheric strength is weak during rifting and that the post-rifting T_e is different for different tectonic units. The lithospheric strengths of the Panyu Low Rise and Lower Slope are larger, with T_e of about 15 km; the T_e of the Northern Depression is about 7 km, and the Baiyun Sag is the weakest in strength, whose T_e is only about 5 km. Lithospheric strength can help to understand the distribution of the basin and the process of lithospheric evolution in the northern continental margin of the South China Sea.

Using plate screening method, a moderately halophilic strain LYG1-1 was isolated from seawater sample offshore of Sanya. According to physiological and biochemical characterizations, 16S rRNA sequences and phylogenetic analysis, cells were Gram-negative. It grew best at 30℃, pH 7.5 and with the presence of 10% NaCl. Phylogenetic analysis based on 16S rRNA gene sequence showed that it belonged to the genus Halomonas, having the highest similarity (99.72%) with Halomonas salina. The maximum esterase activity was observed at 45℃, pH 8.0. The effects of various divalent cations were studied based on the activity of esterase from Halomonas sp. The concentrations of 5 mmol·L^-1 Mg²⁺ and Ca²⁺ enhanced the esterase activity of LYG1-1, while the presence of Hg²⁺ strongly inhibited its activity.

Lipid and fatty acid contents were firstly monitored in the reef coral Acropora hyacinthus during its reproductive cycle by using chloroform-methanol mixture extraction method and gas chromatography-mass spectrometry. The results are summarized here. The lipid content and tissues of the reef coral A. hyacinthus fluctuated markedly during the reproductive process, with the lipid content decreased drastically by approximately 43.4% and the tissues reduced by about 19.6% after reproduction. However, there was no significant difference in symbiotic algae density during the breeding process, implying that the eggs were probably without zooxanthellae. The reef coral A. hyacinthus accumulated lipid in the process of reproduction preparing. EPA (C20:5n-3, eicosapntemacnioc acid) and DHA (C22:6n-3, docosahexaenoic acid) played important roles in reproduction, since their contents changed significantly during this process. EPA and DHA increased by 41.3% and 36.5%, respectively, before breeding. However, their contents decreased by 32.0% and 34.3%, respectively, after breeding. Meanwhile, the content of poly-unsaturated fatty acids (PUFAs) also reduced appreciably, suggesting that they were intimately bound up with the reproduction. Scleractinian corals likely increased feeding to meet the need of fatty acids and energy during the reproductive process.

Symbiosis of coral and zooxanthellae is the primary ecological characteristic of coral reef ecosystem, and photosynthetic efficiency of zooxanthellae decides the health of symbiont. The present study monitored the photochemical efficiency of zooxanthellae within tissues of five typical species of scleractinian corals, Porites Lutea, Galaxea fascicularis, Favia speciosa, Goniastrea favulus and Acropora corymbosa, in a Sanya fringing reef for five consecutive days, and recorded the environmental parameters of the area. Aiming at exploring the potential diurnal change of photosynthetic efficiency, we analyzed the pivotal factors that impede the photosynthesis of symbiotic algae. The results suggested that photosynthetic active radiation (PAR) determines the diurnal variation of Φ_PSⅡ, an indicator of actual photochemical efficiency. Temperature and tidal height also had prevalent influences on corals. In addition, Porites lutea showed the biggest amplitude of daily Φ_PSⅡ than the other four species.

Cruises were carried out to survey urea concentration and urease activity together with other environmental parameters in the Daya Bay. The bioavailability of urea for succession in the phytoplankton community was analyzed based on these cruise data. The results showed that the average concentration of urea varied from 0.81 to 8.54 μmol N·L^-1 in the four seasons. The urea concentration was the highest in summer, up to 4.32±1.65μmol N·L^-1, and the lowest in winter, up to 1.57±0.49 μmol N·L^-1. There were many stations where urea concentrations were 1-3 times higher than dissolved inorganic nitrogen (DIN) in summer and autumn, which suggested that urea as one important nitrogen source should not be ignored in the growth and productivity of phytoplankton in the Daya Bay. Higher levels of urea were distributed in the aquaculture area and the nearshore waters where sewage drains were located. Plankton urease activities were the highest in autumn, up to 61.0 ± 33.6 nmol N ·L^-1·h^-1; however, in winter and spring the urease activities were often below the detection limit. Dinoflagellates densities were closely related to urease activities in autumn. Urease activity has been shown to be the most important way in the hydrolysis of urea by of phytoplankton in the oceans, so urea may affect the growth of dinoflagellates and other phytoplankton in the Daya Bay.

Nuclear division of eggs and cell division of zygote of Sargassum cinereum were observed by tissue culture in vitro. The effects of various salinity values (15‰, 22‰, 26‰, 30‰, 34‰, 38‰, and 42‰) on egg release and early development of S. cinereum germlings were studied under laboratory conditions. The results indicated that the algal eggs could be released normally in the salinity range studied. The eggs were released concentratedly and rapidly in the salinity range of 22‰~34‰; however, at 15‰, 38‰, or 42‰, concentrated egg release was delayed. More eggs were detected at salinity over 30‰ than below 26‰. A freshly released unfertilized egg from the nest hole had only one nucleus in the center, which was then divided into eight daughter nuclei within about 4 hours; finally only one combined with sperm nucleus, and changed into zygote with a large nucleus in the center. The first two cell divisions of zygote were transverse, and the subsequent two were all longitudinal. Four to five hours after fertilization were needed for the four cell division, then zygote cleavage was speeded up and cell number was increased rapidly, and finally a multicellular germling was formed within about 22 hours. The rhizoid grew prior to thallus in the next day, and then thallus length increased gradually. Salinity significantly affected the early development of S. cinereum germlings. Rhizoid grew normally in salinity range of 22‰~38‰; however, higher or lower salinity inhibited its forming and elongation, and the inhibition action at 42‰ was stronger than that at 15‰. In addition, the suitable salinity for growth was 26‰~38‰ for S. cinereum thallus. In conclusion, the suitable salinity was 26‰~34‰, and the optimal salinity was 34‰ for early development of S. cinereum germlings.

Based on the summer cruise conductivity-temperature-depth (CTD) data in 2001, 2002, 2006, and 2009, this paper reveals the interannual variation of spatial structure and intensity of upwelling in eastern Guangdong and southern Fujian coastal seas. Using the QuikSCAT wind data, the current and bottom temperature data from seabed-based observations, and the sea surface temperature data at the ocean station of Nan’ao, we discuss the influence of sea surface wind and tropical cyclones on the upwelling, temporal and spatial characteristics and short-term variation of the upwelling, the evolution of the upwelling, and the source of the upwelling. We show that the range and intensity of the upwelling present an interannual variation in the coastal seas between eastern Guangdong and southern Fujian. The upwelled water only reached the surface in July-August 2009. In the border area of Guangdong and Fujian, the upwelling region was narrow, and was located mostly northeastward in July-August 2006; in contrast, it was wider in July-August 2009, and was located mostly southwestward in July-August 2001. In the eastern Guangdong coastal sea, the upwelled water reached 20 m in July-August 2006, deeper than in other years. The upwelling in the study area was stronger in July-August 2002 than on the other years. A strong vertical mixing within the upwelling area induced by a tropical cyclone warmed the middle- and bottom-layer waters rapidly, and finally led to the disruption of the upwelling. The coastal upwelling appeared earlier and was stronger in eastern Guangdong coast than in southern Fujian coast. During early and mid July, the upwelling started to appear but was not permanent. It was strengthened in mid July and early August, and became weaker from mid August to early September. Finally, it disappeared rapidly during early and mid September. The upwelled water in the coastal seas of eastern Guangdong and southern Fujian came from the lower-layer cold water in the open sea of the eastern Guangdong.

Stirring is an important part of mixing, which can be quantified using Finite Time Lyapunov Exponents (FTLE) based on Lagrangian view. In this paper, we calculated the FTLE of surface ocean derived from satellite altimeter from 2002 to 2011, and then analyzed spatial and temporal variation of horizontal stirring in the South China Sea (SCS). Results show that FTLE in the SCS is not uniform, with high values southeast of Vietnam indicating strong stirring, and low values in the northwest and southeast of the SCS. A slowly increasing trend of stirring in the SCS is observed during the 10 year period. FTLE also displays a seasonal fluctuation, strong in summer but weak in winter. Furthermore, we found that FTLE has a similar spatial distribution with Euler-based eddy kinetic energy (EKE) and strain rate, with high and low values of these three quantities locating roughly in the same areas. A comparison with Okubo-Weiss parameter reveals a strong relationship between vortices and FTLE ridges, referred to as Lagrangian Coherent Structures (LCS). Low values of FTLE are mainly present inside rotation-dominated vortices, while high values occur in strain-dominated regions surrounding the vortices.

Satellite-derived sea surface temperature (SST) data from the MODIS (moderate resolution imaging spectroradiometer)/ Aqua, AMSR-E (advanced microwave scanning radiometer for the earth observing system)/Aqua and MODIS/Terra over the past ~10 years are analyzed to investigate the sea surface diurnal warming in the South China Sea (SCS). The results reveal that sea surface diurnal warming derived by MODIS/Aqua is slightly higher than that by AMSR-E/Aqua and MODIS/Terra, due to the differences in satellite transit time, sampling manner and retrieval algorithm, among others. However, there are no significant biases in terms of spatial and temporal distributions, and of the variation of sea surface diurnal warming over the SCS. The magnitude of sea surface diurnal warming in the SCS is the weakest during winter, and the strongest during spring. The magnitude is generally larger in the southern regions than in the central and northern regions, and is larger in the eastern regions than in the western regions. Northwest of the Luzon Strait, the sea surface diurnal warming tends to appear easily from late spring to early summer. It is suggested that the seasonal variation of sea surface diurnal warming in the SCS be affected by solar radiation, wind speed and cloud amount; among them, the wind speed is the most important factor with a significant negative correlation with the diurnal warming.

The goal of this study is to further explore the nonlinear correlation characteristics between variables in the tropical Pacific ocean-atmosphere system. The data used include the sea surface temperature (SST) data provided by the Hadley Center, and the sea surface wind field and sea level pressure data provided by the U.S. National Center for Environmental Prediction (NCEP) and the National Center for Atmospheric Research (NCAR). The empirical orthogonal function (EOF) analysis and the nonlinear canonical correlative analysis (NLCCA) are used to analyze nonlinear correlations among SST, sea surface wind and sea level pressure. The results show that the Pacific warm pool in the abnormal warming state and the westerly wind anomalies in the tropical western Pacific are two foreboding conditions of ENSO events. Using the singular value decomposition (SVD) method, combined with the NLCCA method, the area affected by coupling and the distribution characteristics of the anisotropic relationship of SST, sea surface wind and sea level pressure in the tropical Pacific Ocean are also analyzed. The results show good correlations exist among the tropical Pacific westerly anomaly, the western Pacific subtropical high and ENSO cycle.

Effects of ration (from starvation to satiation) and temperature (21℃, 27℃ and 31℃) on growth and nitrogen budget of young cobia (initial body weight about 10g) were studied, and the relationship between specific growth rate (SGR) and ration as well as temperature and the nitrogen budget were established in this paper. The results showed that at a given temperature, as ration increased, SGR increased significantly, exhibiting a linear pattern described as a simple function at 33℃ whereas a decelerating pattern described as a logarithmical equations at 27℃ and 21℃. At a given ration, except for starvation, as temperature increased, SGR increased or first increased then decreased, all described as quadric functions. At a given temperature, as ration increased, feed conversion efficiency (FCE) increased at 21℃ and 33℃ whereas first increased then decreased at 27℃. At a given ration (except for the starvation), as temperature increased, FCE increased or first increased then decreased and peaked at 27℃ for fish fed restricted food while there was no significant difference between 27℃ and 33℃ though FCE peaked at 33℃ for fish fed satiation. Over the experimental ration and temperature range excretion nitrogen of young cobia increased significantly with increasing ration and temperature.

Reproductive biological parameters including size composition, sex ratio, percent of maturity, gonadosomatic index (GSI), and so on, were analyzed based on the 353 yellowfin tuna Thunnus albacores samples caught in the waters of the Solomon Islands from September to December, 2012. The results showed that the yellowfin tuna individuals caught consisted of two groups. The body size of female was significantly smaller than for male (p<0.001). The total sex ratio of female to male was 0.67︰1, significantly different from expected 1︰1 from spring to summer. But it was closely related to the months when the samples were taken and to the body size, increasing gradually from September to December, and was close to 1︰1 in December (p>0.05). However, it gradually decreased with fork length (FL) increasing, and males became predominant at 110 cm and larger (p<0.05). Furthermore, the proportion of female showed a linear negative correlation with FL; the correlation coefficient was -0.90 (p<0.01). Both the percentage of maturity and monthly mean of GSI of female and male increased from spring to summer, and in November and December they reached the relatively higher values, and percentage of spawning individuals of V-VI increased, suggesting that spawning population of yellowfin tuna occurred in the waters of the Solomon Islands from spring to summer and that the spawning individuals began to appear in October with a relatively higher proportion of spawning individuals in December investigated. The GSI was positively correlated with FL. The FLs at first maturity of female and male were estimated to be 97.4 cm and 103.7 cm, respectively, based on further analysis results. So, study on reproductive biology of yellowfin tuna helps to understand the status of its fisheries resources and has significance in assessing this stock in this area.

Meiofauna and environmental variables were sampled and analyzed at five deep-sea stations and one shallow-sea station in the northern South China Sea in September 2010. A total of 10 taxa of meiofauna were identified, including Nematoda, Copepoda, Polychaeta, Ostracoda, nauplii, Tanaidacea, Oligochaeta, Turbellaria, Aplacophora, and Isopoda. Nematoda was the most dominant group, accounting for 94.72% of the total meiofauna abundance, followed by Copepoda (2.70%), Polychaeta (1.62%) and other taxa that only account for 0.96%. In terms of biomass, Nematoda accounts for 53.83%, followed by Polychaeta (32.17%), Copepoda (7.14%) and other taxa that account for 6.85%. The average abundance and dry biomass of meiofauna were 566.12±635.61 ind·(10cm²)^-1 and 398.43±431.98 µg·(10cm²)^-1, respectively. Those of Nematoda were 536.21±593.48 ind·(10cm²)^-1 and 214.48±237.39 µg·(10cm²)^-1, respectively. Results of correlation analysis between abundance of nematode, copepod, polychaete, total meiofauna, biomass of total meiofauna and environmental factors showed that the main factors controlling nematode abundance, meiofaunal abundance and biomass were bottom-water pH, silt-clay percentage and sediment organic matter. Results of one-way analysis of variance (ANOVA) showed that there were significant differences for nematode abundance, copepod abundance, total meiofauna abundance, and biomass at different stations. Compared with the Bohai Sea, northern Yellow Sea, southern Yellow Sea, Yangtze River Estuary, Nha Trang Bay (Vietnam), Daya Bay, Beibu Gulf, and the coastal areas of South China Sea, the abundance and biomass of meiofauna in the present study were lower.

We investigated the abundance and biomass of planktonic ciliates along two intersecting transects (Transects A and B) in the Beibu Gulf during summer 2009. The average abundance of ciliates was 521±369 ind·L^-1, the average biomass was 0.63±0.54 μg·L^-1. Ciliate abundance and biomass in the surface layer were higher in the coastal waters and at Station A5 (located in the central gulf). Ciliate abundance and biomass were uniformly distributed vertically in the water column along Transect A, while ciliates tended to accumulate in the upper 15 m along Transect B. Twenty tintinnid species of 13 genera were identified. The most dominant species were Tintinnidium primitivum, Eutintinnus tenuis, Rhabdonella sanyahensis, tintinnid sp., and Tintinnopsis schotti, and they exhibited distinct patterns along the two transects.

Prorocentrum triestinum BBW-02 strain, isolated from the Beibu Gulf of Guangxi province, was described on the basis of morphological characteristics and phylogenetic evolution relationship using light microscopy and molecular sequencing. The cells are lanceolate or heart-shaped, 20-26 μm long and 10-14 μm wide. The anterior spine is spearhead-shaped. The thichocysts of the surface are few, and mainly distribute around the margin irregularly. Two thichocysts distribute approximate symmetrically in the two-third of the theca. Homologous retrieval and system evolution analysis showed that P. triestinum BBW-02 was closely related to the other analysed P. triestinum. Compared with other species, P. triestinum BBW-02 had the most intimate relationship with P. gracile.

Nannochloropsis has been believed to be a promising genus of microalgae, which has the potential as the feed stock for biofuels. To achieve the goal for industrial application, use of genetic modifications to improve oil-producing and growth characters is of great significance in reduction of costs. So, it is necessary to develop an efficient transformation method. Here, a vector pHB4857 that has a sh ble gene derived by Nannochloropsis β-tublin promoter and Phaeodactylum tricornutum fcpA terminator was constructed and transformed in N. gaditana CCAP849/5 by electroporation. Transformants were able to grow on 3 μg·mL^-1 zeocin. PCR detection indicated that 100% of the selected colonies were positive transformants. The efficiency was 1.25×10ˉ⁶. A Southern blot analysis verified that the sh ble gene with single or multiple copies was randomly inserted into the geneome and most of the transformants owned the intact heterologous genes. The transformants were inoculated in fresh zeocin-resistant medium every 10 days for more than seven months. The integration of heterologous gene in the host nuclear genome appeared to be stable since no sh ble gene was lost.

Based on the cruise in the central and southern South China Sea from November 28^th, 2011 to January 12^th, 2012, the characteristics of dissolved aluminum distribution and its correlation with phytoplankton community structure were presented in this paper. The data included 78 dissolved Al samples at 25 stations between 5 and 18°N. The average value of dissolved Al in the surface water was 138.3±39.1 nmol·L^-1, showing a horizontal distribution with high concentration in the continental shelf water and low concentration in the open sea and around islands and reefs. In the surface water samples, we identified 132 phytoplankton species belonging to 57 genera, including Bacillariophyta, Pyrrophyta and Cyanophyta. Phytoplankton biomass fluctuated from 0.75×10³ to 21.09×10³ cell·dm^-3 and showed a significant positive correlation with dissolved Al (n=22, r=0.55, p<0.01). Dissolved Al showed obvious variation from the surface to 100 m in the vertical profiles, but little change from 100 to 300 m. No strong analogy between dissolved Al and nutrients was observed at two vertical profiles. However, dissolved Al exhibited a significant positive correlation with chlorophyll a (n=16, r=0.58, p<0.05), the total abundance of phytoplankton (n=16, r=0.59, p<0.05), and the Pyrrophyta abundance (n=15, r=0.69, p<0.01), which indicates that the dissolved Al may have stimulated Pyrrophyta’s growth in the central and southern South China Sea in winter.

Giant clams are of the family Tridacnidae with 10 living species in only two genera, Tridacna and Hippopus. In the 1980s and 1990s, the Pacific Rim countries, including Australia, the Philippines and the U.S., conducted a series of joint research on the cultivation of giant clams and the relevant physiological, ecological and economic factors. The unique feature of giant clams among bivalve molluscs is their symbiotic relationship with dinoflagellate algae, zooxanthellae (Symbiodinium. sp); this gives them a nutritional and growth advantage over normal bivalve molluscs. Since the stocking of giant clams can reach 400 tonnes per hectare, giant clams have great significance to both mariculture sector and tropical coral reef ecosystem. Moreover, due to benefits to coral reef restoration and carbon sink fisheries, the growth of giant clams also has a significance for marine development and protection. Meantime The South China Sea has 3000 km² tropical reef water, which is suitable for developing mariculture. We suggest that giant clams cultivation have the potential to become a principle sector of tropical mariculture that could facilitates the protection of coral reefs as well as the recovery and conservation of the South China Sea ecosystem.

Foraminiferal Mg/Ca-thermometer is one of the key methods in reconstructing past ocean temperatures. Increasing evidence, however, revealed that precision of Mg/Ca-thermometer is influenced by various factors in addition to seawater temperature. Of these factors, salinity is in particular highlighted. This study measured and collected an amount of more than one thousand Holocene (since about 11 ka B.P.) foraminiferal Mg/Ca ratios from sediment cores recovered from the Indo-Pacific warm pool. These Mg/Ca ratios were converted into temperatures using two conventional equations, with and without salinity involved. Estimated temperatures were then compared to reveal salinity effects on Mg/Ca-thermometer used for samples from the Indo-Pacific warm-pool region. It is shown that values resulted from the two equations are very similar, with a difference of 0.07℃ on average in the case that the estimated temperature is lower than 28℃. In contrast, difference is up to 1℃ when the estimated temperature is higher than 28℃. Moreover, it is also revealed that less saline water and larger seawater oxygen isotope were estimated using the equation involving salinity. These findings imply that salinity likely had little influence on foraminiferal Mg/Ca in this region.

According to research demand, a deep-sea extreme environment simulator was designed. This paper gave an analysis of system architecture principles, and expounded training vessel, temperature control system and pressure control system. Because of low pressure control accuracy for the current simulator, a high precision pressure sensor was designed and an iterative learning PID pressure control algorithm was put forward, which could automatically detect the system pressure and continuously control it. At the same time, a training vessel with two observation windows could take real-time observation of microorganism. Experiments showed that the system can control the vessel pressure accurately and simulate the deep-sea environment; it provides a good platform for deep-sea extreme environment research.

In order to understand the characteristics of atmospheric nutrient deposition, measurements of dry and wet depositions of nitrogen and phosphorus were made at Daya Bay in Huizhou during spring and summer. Results showed that the average atmospheric fluxes were 257.45 and 1.79 kg·km^-2·month^-1 for TN and TP, respectively. Wet deposition had a larger contribution to the total flux than dry deposition for both N and P species. N species showed different variation regularity during the study period; dry deposition fluxes were higher in summer and lower in spring, while wet deposition fluxes showed the opposite trend. For P species, both dry and wet depositions showed no significant difference. With the effect of rainfall and atmospheric transmission caused by monsoon climate and regional pollution, the nutrients in the atmosphere existed mainly in the form of NO₃^--N. N species were the main controlled target of air pollutions at Daya Bay.

Using the data collected during 2010~2012 Eastern Indian Ocean (EIO) cruises, we analyzed the hydrographical features in the upper layer of the southern Bay of Bengal (BoB) and eastern equatorial Indian Ocean (EEIO) during spring monsoon transition. We also studied the variations of meridional geostrophic transport and the thermocline at the mouth of the BoB. The results show that the equatorial westerly wind bursts become the dominant force in this region during spring intermonsoon transition around March-May. They change the equatorial pressure gradient force from eastward to westward by transporting the Arabian Sea water to the east, and weaken the equatorial undercurrent. At the BoB mouth, the wave propagation in the equator enhances the northward water volume transport, mixes the water masses form the Arabian Sea and BoB, and increase the salinity gradient. In addition, the remote forcing of equatorial waves leads to the formation of a cyclonic eddy at the BoB mouth. The remote forcing also deepens the thermocline at the west end in the southern BoB, while the upper-layer low salinity water keeps it shallow at the east end even though the thermocline in the EEIO is deepened.

Using the hydrographic data collected during August 19 to September 12, 2011 and the altimetry data, we studied the characteristics and distribution of water masses in the northern South China Sea (SCS). In this study, fuzzy cluster analysis of temperature and salinity data was employed to categorize the water in the northern SCS vertically in terms of five groups: the coastal mixing water mass (M), the surface water mass (S), the subsurface water mass (U), the intermediate water mass (I), and the deep water mass (D). Results show that there is Kuroshio water intrusion into the SCS in summer 2011, and that the intrusion could reach 119°E. The geostrophic currents derived from the altimetry data show several meso-scale eddies, including two anticyclonic eddies east of Dongsha Island and east of the Luzon Strait, respectively, and a cyclonic eddy south of Dongsha Island. This indicates distinct meso-scale structures of the circulation in the northern SCS in summer 2011, which would influence the vertical distribution of water mass and the Kuroshio intrusion.

Based on the 49-month wave data collected continually at the station of Gyanghai Bay, statistical analysis of wave characteristics was conducted. The results show that the wave height in the bay is usually below 0.5 m. The year-to-year variation of annual-average wave height is small, while the seasonal variation is quite notable. Both the year-to-year and seasonal variations of maximum wave height are prominent. Higher waves occur mainly in summer and autumn, due to tropical cyclones. During Typhoon Hagupit, the wave height increased rapidly, with the maximum wave height reaching 3.55 m. The pattern of typhoon wave was wind-driven wave pattern.

Based on the hydrodynamic model of the environmental fluid dynamics code (EFDC), The water exchange in the Qinglan tidal inlet was calculated in 1965 and 2006 using water age concentration and water quality formula. The results showed that the average water exchange time of the Qinglan tidal inlet was about 107 d in 2006, while it was about 114 d in 1965. This was mainly because the Qinglan harbor channel was dredged to 7~8m, which led to significantly enhanced tidal energy and the increase of tidal prism by 4.3%.

A ship wake automatic identification algorithm based on improved Hough Transform is proposed in this paper. First, the algorithm detects the ship and replaces the pixels’ gray value of the detected ship with the gray mean value of the image. Second, the peaks are modified in the Hough transform filed through setting a threshold. Third, ship wake detection and identification are realized automatically with improved Hough transform. Finally, it confirms the beginning and the end of the ship wake with constraint conditions. The experiment of wake detection in the advanced synthetic aperture radar image showed that the algorithm can detect ship wake, identify the kind of ship wake automatically and derive the beginning and end of the wake, which is significant for marine monitoring and management.

Based on the data from 1990 to 2008, which includes meteorological elements, tropical cyclone tracks and data at nine tidal stations along the Fujian coast, the characteristics of storm surges caused by tropical cyclones along the Fujian coast were analyzed. The aspect of tropical cyclone tracks and geographical features of the Fujian coast were considered in the study. The results show that there were on average 5.58 tropical cyclones that make landfall or affect Fujian province every year. The incidence of storm surge was 81.1%. The storm surges along the Fujian coast mainly occurred from May to October, and most frequently in August and September. On average, 4.53 storm surges occurred along the Fujian coast every year. The tropical cyclones that entered Fujian province or made landfall in southern Zhejiang province initiated storm surges most easily. In these situations, the storm surge would be the strongest and the maximum water increment would exceed 200 cm. The tropical cyclones that landed in Guangdong province could also cause storm surges along the Fujian coast. Due to the trumpet-shaped topography, the Minjiang Estuary segment, which is located at the mouth of the Minjiang River, became the place where the storm surges were the strongest.

The four component ocean bottom seismometer (OBS) is a new instrument. The seismic data obtained from the OBS contains a large amount of information; it has high SNR (signal-to-noise ratio) and abundant frequency compared to streamer data. The study of deep crustal structure has achieved good progress using OBS data, but the studies of oil-gas exploration and basin structure have achieved less progress. Using large capacity air-gun array (0.083 m³) as source in the northwestern South China Sea, we obtained seismic information from reflection and refraction data from the OBS, and then interpreted it for oil-gas exploration in an attempt. To properly use the OBS seismic data, we must adopt the method that is different from conventional seismic data processing method, in this paper we proposed a new method which used the method of mirror time migration of pre-stack processing. The method includes the OBS data vector fidelity processing, the P (pressure) and Z (vertical) component of the pre-stack processing and image of pre-stack time migration processing; the vector fidelity processing is to control and correct the positioning in space (x, y, z) and in time (clock drift), and the geophone sensor orientation (vertical and horizontal components); the P and Z component of the pre-stack processing includes zero phase processing and seismic- channel correcting, P and Z summation, residual static correction, image superposition and multiple attenuation; mirroring the pre-stack time migration processing is to use the multiple wave imaging technology. Using the mirror of pre-stack time migration processing, good imaging profile can be obtained.

All coral atolls consist of several facies zones. Tidal inlet, which is the channel to connect the lagoon and the sea, has different geometric shapes. According to different angle and principle, coral atolls have been classified into various types. In order to identify the open type of atolls quantificationally, two geometric parameters of tidal inlet are regarded as new metrical factors to construct a new expression. The new description function is the ratio of tidal inlet’s width to atoll’s midline. Finally, the threshold division of the atolls’ type is formed on the basis of the new expression. The threshold result shows that the open degree of the enclosed atolls is 0, the contiguous enclosed atolls is between 0 and 0.06, the half-opening atolls’ is between 0.06 and 0.25, and the opening atolls’ is between 0.25 and 1. Thus, the new function can be used to reflect the openness of different atolls for development regularity of coral atolls in the South China Sea.

This study investigated the genetic characteristics of mitochondrial COⅠ?(mitochondrial cytochrome c oxidase subunit Ⅰ) and 16S rRNA gene fragments and their applicability in species identification and phylogeny of sole fish Through sequencing and downloading available data from the GenBank, we obtained COⅠ?gene fragments from 65 individuals of 24 species in 14 genera and 16S rRNA gene fragments from 62 individuals of 23 species in 14 genera of Soleidae, respectively. Results of base composition analysis showed that the A+T content was higher than 50% except for 16S rRNA sequence of B. luteum (49.8%). The proportion of variation base of COⅠ?(about 45.5%) was a little higher than that of 16S rRNA (about 44.3%). Means of intraspecific and interspecific K2P genetic distances were respectively 0.33% and 19.91% for COⅠ sequences, and 0.26% and 7.19% for 16S rRNA sequences. Genetic differences of COⅠ?sequences between congeners were, on average, about 60 times (minimum 19 times) higher than the differences within species, which met Hebert’s species identification standard (more than 10 times the difference between intraspecies and interspecies). Genetic differences of 16S rRNA sequences were 28 times between intraspecies and interspecies (minimum five times). Therefore, COⅠ and 16S rRNA sequences were both applicable for species identification in sole fish. Moreover, there were overlaps in genetic distance distribution of the two gene fragments between different taxa. The overlap region in COⅠ-based genetic distance distribution existed in higher taxa (interspecies, genus, family), while that in 16S rRNA sequence existed in lower taxa (intraspecies, interspecies, genus) 16S rRNA. As a result, it is advisable to select appropriate molecular markers according to different classified levels when applying the two gene fragments for studying systematic evolution.

Based on the research from the time scale from 1997 to 2008, we aim to study the coastal wetlands’ dynamic changes in Zhuhai City. Taking the 1997, 2000, 2004, and 2008 images as the information sources, in combination with other survey data and the support of the geographic information system, a landscape classification system for Zhuhai City was set up and related landscape information was extracted. On that basis, we select some socio-economic indicator of Zhuhai City. With the help of statistic software of SPSS and using canonical correlation analysis, we proclaim the correlation correlativity between the area change of each kind of coastal wetland and the elements of economic and society, and carry on research on the driving force that causes the coastal wetlands’ changes.

Surface sediments were collected from the Xiamen Gulf in March 2010. The sediments were analyzed with modified SEDEX (sequential extraction and separation analysis method) to obtain Ads-P (absorbed phosphorus), Fe-P (iron-bound phosphorus), Ca-P (phosphate bound onto CaCO₃), De-P (detritus phosphorus), and OP (organic phosphorus). Along with environmental parameters of sediments, the geochemistry characters of phosphorus were discussed．The mean contents of Ads-P, Fe-P, De-P, Ca-P, OP, and TP (total phosphorus) were 9.80, 48.69, 14.07, 136.89, 91.97, and 401.41 μg?g^-1, respectively. The results showed that TP was weakly influenced by terrestrial input, and De-P, OP and Fe-P were mainly influenced by terrestrial input. Ads-P and Ca-P were mainly from biogeochemical processes of the sea area. Ca-P, De-P and OP with heavy metals (Cu, Pb, Cd, and As) possessed chemical coupling, and might have similar geochemical behavior in the deposition process.

The concentrations, spatial distributions and sources of heavy metals in the surface sediments of the coastal wetland on the Leizhou Peninsular were analyzed through multiple statistics. The ecological risk assessments of heavy metals were conducted. The mean concentrations of Cu, Zn, Pb, Cr, As, Cd, and Hg were 10.29±7.80, 47.06±28.47, 24.74±10.78, 41.70±26.25, 7.98±4.73, 0.042±0.029, and 0.020±0.027 μg·g^-1, respectively. High positive correlations were found in two groups among the seven metals. The metals including Cu, Zn and Cr in the first group were mainly originated naturally, whereas the second group consisting of Pb, Cd and Hg were originated from both human activities and natural sources. The high concentration areas of the metals were in the Liusha Bay, western Zhanjiang Bay, Hai’an Bay, and western Leizhou Bay. According to the biological effect criterion suggested by the NOAA, nearly no negative effects would occur for the metals in the study area except As. This is because its concentration is between the effect range low (ERL) and effect range median (ERM) level at about 50% of the sampling stations, which indicates the negative effects would occur occasionally. The degree of contamination and potential ecological risk index of the heavy metals were both low for the whole study area. However, the contaminations in some areas such as the western Zhangjiang Bay, Liusha Bay and Hai’an Bay need further investigation and monitoring to avoid inducing ecological risk to benthos under continued accumulation due to human activities.