Seasonal dynamics of the density of the crab larvae (Decapoda: Brachyura et Anomura) in Minonosok Bay of Pos’eta Bay (Peter the Great Bay, Sea of Japan)

As the materials for this project, we used data on the distribution of the larvae of the Asian paddle crab Charybdis japonicus (A. Milne-Edwards, 1861); the spider crabs Hyas coarctatus ursinus (=Hyas ursinus) (Rathbun, 1924), Pugettia quadridens (de Haan, 1839), and Pisoides bidentatus (H. Milne-Edwards, 1873); the samurai crab Paradorippe granulata (=Dorippe granulata) (de Haan, 1841); the pea crab Pinnixa rathbuni (Sakai, 1934); and the porcelain crab Pachycheles stevensii (Stimpson, 1858) in Minonosok Bay of Pos’eta Bay obtained during 2000–2002 and in 2004. The planktonic samples were collected from the last third of May to September. The greatest density of the larvae was observed in May, mid-June, late June-early July, and late July-early August. The greatest densities of the crab larvae and the decapod larvae ranged from 20.4 to 48.2 and from 88.4 to 245.3 specimens/m³. The schedule of the crab larvae’s occurrence in the plankton is provided for the first time. The distribution of the density showed pronounced patchiness.     

Geochemical characteristic of hydrocarbon compounds in the Hangzhou Bay

The source and distribution of the organic pollutants such as the oil , n-alkanes籥romatic,and the pesticide in the water column, suspended particulates and surface sediments in the Hangzhou Bay (HB) during winter 1987 and summer 1988 are studied with analytical method of fluorometry, GC, LC, GC-MS, etc.The influence of the tide and salinity on the distribution of dissolved and paniculate organic matter is investigated in this paper. The data show that the highest content of suspending silt, organic matter > and chemical oxygen demand (COD) occurs at salinity 15. This results from the fact that the water front limits the transfer and dispersion of the matter in different water mass, and enriches the suspending silt and organic matter in water column.The running direction of the oil-content equivalue lines is similar to that of the water front, and interrelated closely with the terrestrial materials from the Changjiang River.     

Long-term evolution (1988–2008) of Zostera spp. meadows in Arcachon Bay (Bay of Biscay)

The spatial variability of seagrass meadows in Arcachon Bay, was studied between 1988 and 2008 using a combination of mapping techniques based on aerial photographs for intertidal dwarf-grass (Zostera noltii) beds and acoustic sonar for permanently submerged eelgrass (Zostera marina) populations. The results show a severe decline over the period for both species, as well as an acceleration of the decline since 2005 for Z. noltii. The total surface regression over the studied period is estimated to be 22.8 km² for Z. noltii and 2.7 km² for Z. marina, which represent declines of 33 and 74% respectively.     

Distribution Pattern of Heavy Metals in the Surface Sediments of the Jiaozhou Bay

Introduction Due to the joint influence of hydrodynamics and the impacts of biological and human activities, the distribution pattern of heavy metals in the coastal sediments becomes rather complicated. The question has raised attention from the world geocommunities since the 1970s. During the past 30 years, a lot of data have been accumulated [1-7]. The study of heavy metals in the sea bottom sediments began in the 1980s in China [8-13]. It includes the study of sources, occurrence, depositi…     

Study on fishery biology features of spawning group of Pseudopleuronectes yokamae(Gunther) in the Sheath Bay

Pseudopleuronectes yokamae (Günther) is one of the most important economic fish species in the genus living specially in the northwest Pacific, and is distributed in the southern area of the far east sea of Russia, Japan, Korea, the Huanghai Sea, the Bohai Sea and the northern area of the East China Sea. Usually they live in nearshore waters of these areas as geographic subpopulations. P. yokamae in the Sheath Bay belongs to a local group of the Huanghai-Bohai Sea subpopulation and is distributed in the mouth and adjacent waters of the bay all the year round, and the catch of its spawning group has     

Residual currents in plume front zone of the Hangzhou Bay

It is of some limitations to analyse residual currents by means of the 25 h anchored current measurements. On the basis of the drift tracking and the mooring system data, here, analyses have been done aiming at the structural characteristics and the dynamical mechanisms of the frontal residual current field of the Hangzhou Bay. Especially a theoritical model is given focusing on the frontal density-driven currents. The results indicate that there exists obviously the upper-layer front-driven flow along the orientation of the front during neap tides in the research area of the Hangzhou Bay. But the flow is restrained by the strong vortical viscosity during spring tides. In the lower layer, the effect of the front is little and the subtidal movements are dominated by the tide-induced residual currents. In addition, the influences of wind forcing to the residual current field are also suggested to be important.     

Mechanisms of low-frequency sea level fluctuations in the Hangzhou Bay

-low-frequency sea level fluctuations in the Hangzhou Bay in winter and summer, 1973-1974 are analyzed in this paper. The established multi-spectrum response models effectively identify the different dynamical factors and their contributions to the low-frequency sea level fluctuations inside the bay. The results show that the Ekman transport due to longshore winds is the major mechanism to induce the sea level fluctuations, more important than the frictional effect of local winds. There also exists obviously the influental effect of the free fluctuations of the continental shelf. In addition ,a simple estimation suggests that the remarkable sea level fluctuation of 0. 4 d-1 in the bay is related to the resonance of the Huanghai Sea and the Bohai Sea (taken as a single bay).     

Fronts and transport of suspended matter in the Hangzhou Bay

A persistent, year-round NE-SW front is found to exist inside the Hangzhou Bay. This front is actually the merging of the secondary Changjiang plume front from the bay mouth and the Qiantang plume front from the upstream side of the bay. During neap tides low runoff periods these two plumes can readily be identified. Our findings suggest that suspended matter is transported into the bay through the north end by the secondary Changjiang plume. The front inside the bay acts the part of concentrating suspended matter, and also plays an important role in both the fine-grained sediment and heavy metal distributions in this sedimentary basin.     

Genetic structure of the common sole (Solea solea) in the Bay of Biscay: Nurseries as units of selection?

Coastal and estuarine areas in the Bay of Biscay are essential nursery habitats for sole (Solea solea). Using three intronic markers, we investigated patterns of genetic differentiation among cohorts of juveniles (0+, 1+, sub-adults) inhabiting four major nurseries in the Vilaine and Loire river estuaries, the Pertuis d'Antioche strait, and the Gironde estuary. Genetic differentiation was not significant for the age 0- and 1-groups, but was among sub-adult samples (θ_WC = 0.017; P = 0.031). Hierarchical analyses of genotypic frequencies by nested multivariate ANOVA using redundancy analysis indicated that northern nurseries of Loire and Vilaine rivers had different patterns of genotypic variation with age than southern nurseries of the Pertuis d'Antioche and Gironde estuaries (F = 1.36; P = 0.007). Bay of Biscay nurseries appeared to be spatially structured between a southern and a northern group that exhibit different genotypic distributions. Genetic drift and gene flow explains this pattern poorly, but a statistical test (P < 0.035) suggested that the metallothionein (MT) locus may be significantly impacted by selection in southern estuaries. As metallothionein is involved in heavy-metal detoxification, and southern nurseries are known to be affected by cadmium, this indicates a possible correlation between observed genotypic distributions and some nursery habitat features in sole. Some selective patterns might also be proposed to explain patterns of linkage disequilibrium observed at amylase loci in three of the four nurseries.     

Ecological characteristics of the abundance and distribution of bacteria in the waters nearby the front of the Hangzhou Bay

- Abundance of total bacteria, heterotrophic bacteria, coliform and oil degradable bacteria and their relations with salinity and suspended matter in the frontal waters in the Hangzhou Bay are described. The results obtained show that the highest abundances of total bacteria , heterotrophic bacteria are encountered around the front and near the northern shore of the Hangzhou Bay, where a positive correlation ( r =0. 70) between the total bacteria abundance and the total suspended matter (TSM) is persent. Moreover,the abundance of oil degradable bacteria being an indicator of oil pollution, is also high in that region.     

Phytoplankton ecology in the adjacent waters of the Daya Bay Nuclear Power Station in Guangdong in spring

The purpose of this study is to detail the ecological characteristics of phytoplankton in waters around the Daya Bay Nuclear Power Station in Guangdong (GNPS) (Fig. 1) in spring, the bloom period of algae. The collections with a small temporal scale of every three days were made during 30 cruises from March to May in 1987. Such an investigation has never been carried out before in China except that the seasonal distribution and composition of phytoplankton in these regions were reported in     

Annual change of the number of anaerobic sulf ite reducing bacteria in sediment of the Daya Bay

The surface sediment samples were collected month by month at nine stations in the Daya Bay from January to December 1987, and the number of anaerobic sulfite reducing bacteria and their spores and the regularity of seasonal change were determined. The effect of environmental factors, water temperature and the resoluble oxygen concentration in the bottom of seawater on the number of them were discussed. The results show that the number of anaerobic su|fite reducing bacteria were low in sediment of the Daya Bay, indicating that the hay was less contaminated.     

Distribution of chlorophyll a and some ecological factors in the Daya Bay

The marine environment, productivity and potential biotic resources in the waters of the Daya Bay were investigated by South China Sea Institute of Oceanology, Academia Sinica from 1984 to 1986. The present paper deals mainly with the annual variation and distribution characteristics in chlorophyll a and with some of the ecological factors involved in chlorophyll distribution within the bay. Correlation models are established and discussed. The results could be helpful for further probing into ecosystem and for the exploitation-utilization of aquatic resources in this region.     

Dynamics of the Organic Matter Content of Bottom Sediments along the Razdolnaya River–Amur Bay Boundary (Sea of Japan)

Oceanology - The contents of Corg, humiс acids (HA), and fulvic acids (FA) in soil and riverine and marine bottom sediments have been investigated along a transect between the Razdolnaya...     

Simulation of Pollutant Transport in Marmaris Bay

The circulation pattern and the pollutant transport in the Marmaris Bay are simulated by the developed three-dimensional baroclinic model. The Marmaris Bay is located at the Mediterranean Sea coast of Turkey. Since the sp ring tidal range is typically 20- 30 cm, the dominant forcing for the circulation and water exchange is due to the wind action. In the Marmaris Bay, there is sea outfall discharging directly into the bay. and that threats the bay water quality significantly. The current patterns in the vicinity of the outfall have been observed by tracking drogues which are moved by currents at different water depths. In the simulations of pollutant transport, the coliforms-counts is used as the tracer. The model provides realistic predictions for the circulation and pollutant transport in the Marmaris Bay. The transport model component predictions well agree with the results of a laboratory model study.     

Organic Compounds in Bottom Sediments under Conditions of Coastal Urbanization (a Case Study of Kazach’ya Bay of the Black Sea)

Oceanology - Data on the hydrocarbon composition of bottom sediments from a water area adjacent to an area with massive cottage construction (Kazach’ya Bay, coast of Sevastopol, the Black...     

Sedimentary Waves of the Southeastern Barents Sea Shelf (Kanin Peninsula–Cheshskaya Bay)

Oceanology - Sedimentary waves are represented by a series of wavelike accumulative features with various degrees of morphological expression. These morphological forms are superimposed on the...     

Simulation of transport mechanism of radium isotopes in aquifer on the southern coast of Laizhou Bay

Naturally occurring radium(²²³Ra, ²²⁴Ra, ²²⁶Ra, and ²²⁸Ra) isotopes have been widely applied as geochemical tracers in marine environments, especially when estimating the submarine groundwater discharge(SGD). In this sense, the influencing factors and transport mechanism of radium isotope activity in aquifers can be key information for SGD estimation. This work evaluates the adsorption/desorption behavior of ²²⁴Ra and ²²⁶Ra in the...     

Study on fishery biology features of spawning group of Pseudopleuronectes yokamae(Günther) in the Sheath Bay

Pseudopleuronectes yokamae (Günther) is one of the most important economic fish species in the genus living specially in the northwest Pacific, and is distributed in the southern area of the far east sea of Russia, Japan, Korea, the Huanghai Sea, the Bohai Sea and the northern area of the East China Sea. Usually they live in nearshore waters of these areas as geographic subpopulations. P. yokamae in the Sheath Bay belongs to a local group of the Huanghai-Bohai Sea subpopulation and is distributed in the mouth and adjacent waters of the bay all the year round, and the catch of its spawning group has important economic value in the area. In this paper the fishery biology features of spawning group of P. yokamae in the Sheath Bay is systematically studied to give biology evidence for proper utilization and the multiplification of its resources.