东海表层沉积硅藻组合与环境关系研究

对东海表层沉积硅藻分析研究,共发现有103种和变种,根据其中分布特征和规律,结合因子负荷变化曲线,把东海表层沉积分为六个硅藻组合和分布区,并探讨影响硅藻分布的环境因素,为恢复古环境提供科学依据。     

Diatoms in surface sediments of the Gotland Basin in the Baltic Sea

A sediment core, 55 cm long, from station F81 in the Gotland Basin of the Baltic Sea was analysed for diatoms and ebridians. Chrysophyte stomatocysts found in the core were also counted but not identified. The aim was to trace environmental changes, e.g. eutrophication and salinity variations. There is evidence that eutrophication has been increasing in the Baltic Sea in recent decades.Brackish-marine plankton diatoms dominate the entire core and reflect the local planktonic taxa rather well. The dominant taxon is the polyhalobous Actinocyclus octonarius. The main biostratigraphical change within the core analysed takes place at a depth of about 22 cm, where the abundance of diatoms, and especially of Chaetoceros spp., Thalassiosira hyberborea var. pelagica and T. baltica start to increase. This may reflect eutrophication which can be estimated to have started c. 200 years ago.     

New Data on Scleractinians from the Northwestern Sea of Japan

three species of scleractinians, individual caryophyllids Caryophyllia alaskensis, C. japonica, and the colonial dendrophyllid Dendrophyllia arbuscula were described for the first time for the Sea of Japan. The findings of these corals in different areas of Peter the Great Bay, Sea of Japan, allow us to expand their geographic range and the depth range of their distribution. The depth of inhabitation reached 1280 m for C. alaskensis and up to 15–3 m deep for D. arbuscula.     

Diatom flora of surface sediments of the Amur River Estuary and adjacent areas of the Sea of Japan and the Sea of Okhotsk

Results of the study of the diatom flora from surface sediments of the Amur River Estuary and adjacent areas of the Sea of Japan and the Sea of Okhotsk are presented for the first time. This study revealed high species diversity of diatoms: 287 diatom taxa belonging to 80 genera were identified in 35 surface sediment samples. The ecological composition of diatom assemblages allowed us to evaluate the influence of the Amur River runoff on adjacent areas of the seas.     

The Meroplankton of Amurskii Bay (Peter the Great Bay,Sea of Japan)

Russian Journal of Marine Biology - The composition and seasonal dynamics of meroplankton in Amurskii Bay (Sea of Japan) were studied for the first time. The total survey period exceeded two years....     

Some Data on the Composition and Distribution of the Meiofauna in Vostok Bay (Sea of Japan)

The effect of some environmental factors on the composition and spatial distribution of the meiobenthos were studied in Vostok Bay. The spatial density of the meiobenthos significantly positively correlated with ground type and was maximum in fine- grained sands. The eumeiobenthos was dominated by harpacticoids in coarse-grained ground and by nematodes in ground with a high silt content. The pseudomeiobenthos was dominated by polychaetes and bivalve mollusks in all ground types. The depth distribution of the meiobenthos was highly heterogenous, harpacticoids being the only group whose distribution correlated significantly with depth.     

Vertical distribution of hydroids in wharf fouling in the Northwestern Sea of Japan

The features of the vertical distribution of hydroids on various types of wharves in the northwest part of the Sea of Japan were studied. It was shown that the highest values of biomass of the common species of hydroids Obelia longissima and Bougainvillia ramosa were at wharf sites below the zone of varying submergence up to a depth of 1 m. The spatial variability of hydroid abundance is discussed in relation to the local specifics of their environment and the character of formation and the structure of the fouling community.     

New data about the distribution and migrations of pink salmon in the Sea of Japan

Data are presented for the first time on the quantitative distribution of pink salmon yearlings in the autumn period in the northwestern Sea of Japan that characterize one of the stages of salmon migrations toward wintering grounds. Data are presented concerning pink salmon wintering in near-bottom water layers near southwestern Sakhalin.Original Russian Text Copyright © 2005 by Biologiya Morya, Temnykh, Loboda, Ilinskii.     

Steryl chlorin esters in sediments of the southern Baltic Sea

Sediments of the southern Baltic Sea were analysed for content of steryl chlorin esters, the chlorin compounds discovered recently in the marine environment. The chlorin esters occur in the Baltic sediments in substantial amounts and form a considerable fraction of the total chlorin content. Among the physicochemical parameters studied the highest correlation with the steryl chlorins showed organic carbon content in sediments and the content of fraction of sediments smaller than 10 μm. A significant correlation was observed between the steryl chlorins content and other chlorins as chlorophylla, phaeophytina, pyrophaeophytina as well as with β-carotene, the distinctly less significant correlation was with phaeophorbidea. This indicates an other way of formation of the steryl chlorins from algae than zooplankton grazing.     

Transfer function between surface sediment diatom assemblages and sea-surface temperature and salinity of the Labrador Sea

Q-mode factor analysis (CABFAC) of 38 diatom species in 66 surface sediment samples from the Labrador Sea allowed the definition of six assemblages explaining 95.69% of the total variance. The first assemblage (40.12% of the total variance) is represented by Thalassiothrix longissima, a species characteristic of the Irminger Current and associated with the West Greenland Current. The second assemblage (34.52% of the total variance) is represented by Thalassiosira gravida (resting spores), a cold water species associated with the Labrador Current. A third assemblage (11.43% of the variance) represented by Chaetoceros spp. is concentrated in the northeastern section of the Labrador Sea and associated with upwelling and high productivity. The fourth, the fifth and the sixth assemblages, represented, respectively, by Coscinodiscus marginatus, Coscinodiscus oculus iridis, and Coscinodiscus divisus, and Nitzschia frigida, are less significant and account, respectively, for 4.95, 2.62 and 2.04% of the total variance. Transfer functions derived by relating factor assemblages to surface water temperature and salinity (August and February) give standard errors of estimate of ±0.93°C (August) and ±0.64°C (February) for temperature, and of ±0.58‰ (August) and ±0.45‰ (February) for salinity. High correlations between the measured and estimated parameters confirm the validity of the paleoecological equations for the reconstruction of the Labrador Sea paleoclimate.     

Molecular phylogenetic and chemical analyses of the microbial mats in deep-sea cold seep sediments at the northeastern Japan Sea

Microbial communities inhabiting deep-sea cold seep sediments at the northeastern Japan Sea were characterized by molecular phylogenetic and chemical analyses. White patchy microbial mats were observed along the fault offshore the Hokkaido Island and sediment samples were collected from two stations at the southern foot of the Shiribeshi seamount (M1 site at a depth of 2,961 m on the active fault) and off the Motta Cape site (M2 site at a depth of 3,064 m off the active fault). The phylogenetic and terminal-restriction fragment polymorphism analyses of PCR-amplified 16S rRNA genes revealed that microbial community structures were different between two sampling stations. The members of ANME-2 archaea and diverse bacterial components including sulfate reducers within Deltaproteobacteria were detected from M1 site, indicating the occurrence of biologically mediated anaerobic oxidation of methane, while microbial community at M2 site was predominantly composed of members of Marine Crenarchaeota group I, sulfate reducers of Deltaproteobacteria, and sulfur oxidizers of Epsilonproteobacteria. Chemical analyses of seawater above microbial mats suggested that concentrations of sulfate and methane at M1 site were largely decreased relative to those at M2 site and carbon isotopic composition of methane at M1 site shifted heavier (¹³C-enriched), the results of which are consistent with molecular analyses. These results suggest that the mat microbial communities in deep-sea cold seep sediments at the northeastern Japan Sea are significantly responsible for sulfur and carbon circulations and the geological activity associated with plate movements serves unique microbial habitats in deep-sea environments.     

Diatoms of the genus Attheya west, 1860 from the Sea of Japan

This paper documents the species diversity of the diatom genus Attheya from the Sea of Japan. Two species (A. arenicola and A. longicornis) were studied in field samples and in culture. Their morphology is described using light and electron microscopy; the ecology and the distribution data are provided. A. arenicola is a new record for the seas of Russia.     

Distribution and contamination pattern of heavy metals from surface sediments in the southern part of Caspian Sea,Iran

This study concentrates on the speciation and distribution patterns of some heavy metals (Pb, Ni, Cd, Zn, and Cu) in surface sediments in the southern part of the Caspian Sea, the biggest lake in the world, to obtain an overall classification for the origins of metals in the area using a sequential extraction technique. At all sampling stations, Pb, Ni, Zn, and Cu were mostly (>50%) accumulated in the resistant fraction, which indicated that there were no significant anthropogenic inputs of Pb, Ni, Zn, and Cu into the surface sediments of the south Caspian Sea. Guilan province on the west coast of Caspian Sea accumulated higher percentages of non-resistant fractions of Pb and Zn, while Mazandaran and Golestan provinces in the middle and western parts of the Caspian Sea, in the Iranian zone, accumulated higher percentages of non-resistant fractions of Ni and Cu. The present study revealed that the coastal area of the south Caspian Sea is still not seriously contaminated. Cadmium in Guilan and Golestan provinces were dominated by non-resistant fractions (55–69%), which indicated more anthropogenic inputs of Cd on the south coast of the Caspian Sea in comparison with other metals.     

Fauna of Calcareous Sponges (Calcarea) in Russian Waters of the Sea of Japan

Based on the collection of the Zoological Institute (Russian Academy of Sciences, St. Petersburg) and the data available in the literature, a list of calcareous sponges (Calcarea) of the Russian waters of the Sea of Japan was compiled. It comprises 15 species belonging to ten genera and seven families. Among these sponges, five species were found in the Sea of Japan for the first time: Leucetta poculiformis (Hozawa), Sycon protectum Lambe, Grantia uchidai Hozawa et Tanita, Heteropia medioarticulata Hozawa, and Leucopsila stilifera (Schmidt). Data on the distribution and ecology of the calcareous sponges in the area of study are reported.     

Eco-physiological characteristic of some common caprellid species in the Possjet Bay (the Japan Sea)

Parameters of equations relating wet and dry body weight to length have been calculated for four species of caprellids from the Japan Sea (Possjet Bay), specifically Caprella cristibrachium, C. kroyeri, C. penantis, and C. bispinosa. A common equation was obtained for oxygen consumption rate in relation to body weight. It was shown that within the Order Amphipoda the metabolic rate of caprellids is 1.5 times lower than that of gammarids. The differences in the fecundity of gravid females of four species and females of one species in the spring and summer, respectively, are shown. At the same time the relationship between number of eggs per female and wet body weight of female is approximated by one equation. The equation obtained shows that caprellids represent an ecologically homogeneous group.     

Parmales species (siliceous marine nanoplankton) in surface sediments of the Weddell Sea, Southern Ocean: indicators for sea ice environment?

The distribution pattern of the Parmales, a recently described order of siliceous marine nanophytoplankton, is described and quantified in surface sediments of the Atlantic sector of the Southern Ocean. Additional samples were investigated from the Bransfield Strait and the eastern Bellingshausen Sea. Highest abundances occurred in nearshore areas of the southern and southeastern Weddell Sea. Due to the distribution of Parmales species, which is strictly linked to these neritic areas, influenced most of the year by sea ice, it is suggested that the presence of Parmales species may be an indicator of sea ice influence probably useful in later down core studies.     

Vertical Distribution of the Far East Trepang Apostichopus japonicusin Vostok Bay,Sea of Japan

The abundance, weight, and age structure of aggregations of the Far East trepang Apostichopus japonicuswere studied in Vostok Bay, Sea of Japan, during the first part of September 2000. The highest density of aggregations (8.3 ± 0.5 ind/m²) and biomass (131.88 ± 10.50 g/m²) of animals was characteristic for coastal sites at the depth 0.5–1.5 m. With anincrease in depth the biomass and density of A. japonicusreduced 1.5 and 3 (depth 5–6 m), 220 and 830 times (depth 8–15 m) respectively. The ratio of large animals concurrently increased in the aggregation structure. The specifics of the distribution and spatial variability of the aggregation structure are discussed in relation to uncontrolled fishing of holothurians of large sizes.     

Abundance and distribution of toxic Alexandrium tamarense resting cysts in the sediments of the Chukchi Sea and the eastern Bering Sea

Abundance and distribution of the toxic dinoflagellate Alexandrium tamarense species complex resting cyst were investigated in the eastern Bering Sea and the Chukchi Sea for the first time. Sediment samples (top 0–3 cm depth) were collected from the continental shelf of the eastern Bering Sea (17 stations) and the Chukchi Sea (13 stations) together with a long core sample (top 0–21 cm depth) from one station in the Chukchi Sea during 2009–2012. The cysts were enumerated using the primuline staining method. Species identification of the cysts was carried out with multiplex PCR assay and the plate morphology of vegetative cells germinated from cysts in the both areas. Alexandrium cysts were widely detected in the both areas, ranging from not detected (<1 cysts cm⁻³) to 835 cysts cm⁻³ wet sediment in the eastern Bering Sea and from not detected (<1 cysts cm⁻³) to 10,600 cysts cm⁻³ in the Chukchi Sea, and all isolated cysts were genetically and morphologically identified as the North American clade A. tamarense. Their cysts were mainly distributed in the shallow continental shelf where the water depth was less than 100 m in both areas. The cysts were detected from the deep layer (18–21 cm depth of sediment core) of the long core sample. The present study confirmed the abundant existence of A. tamarense with wide range of distribution in these areas. This fact suggests that A. tamarense vegetative cells have appeared in the water column in the both areas. Furthermore, these abundant cyst depositions indicate that this species originally distributed in the Arctic and subarctic regions and well adapted to the environments in the marginal ice zone.     

Diatom assemblages in superficial sediments from the Gulf of Riga,eastern Baltic Sea

Twenty one superficial sediment samples from areas of high and moderate eutrophication in the Gulf of Riga were studied with respect to siliceous microfossils, mainly diatoms.The results seem to imply that the number of taxa and the abundance of the frustules are affected by runoff from rivers and the degree of eutrophication in different parts of the Gulf. Areas with high eutrophication, e.g. the river estuaries, have diatom assemblages of varying composition, while in areas with moderate eutrophication the composition is almost constant and the influx of freshwater diatoms and littoral periphyton small. The high abundance and low diversity of brackish-marine and brackish, planktonic diatoms seem to be a result of an influx of nutrients and pollutants in the water and bottom sediments. The sea ice diatoms occurring in the Baltic waters and also in the Gulf of Riga tend to be resistant to eutrophication or are even favoured by it.     

Mesocosm experiments: mimicking seasonal developments of microbial variables in North Sea sediments

This study investigated the suitability of mesocosms for studying the seasonal development of microbial variables in the benthic system of the North Sea. Undisturbed sediment cores were taken from two locations in the North Sea, one with sandy sediment (28 m depth) and the other with silty sediment (38 m depth) and installed in mesocosms in January–April 1989. Cores were kept as in situ temperature in the dark until December 1989. One set of sandy and silty sediments was starved and the other set received a supply of organic matter in May–June, simulating the settlement of the spring bloom of Phaeocystis pouchetii. Seasonal developments in bacterial production (methyl ³H-thymidine incorporation), abundance and biomass of bacteria and nanoflagellates and oxygen consumption were compared between the mesocosms and the field in surface sediments every 1.5 to 2.5 months. Effects of seasonal temperature variations (range 6–17.5 °C) on microbial variables in starved mesocosms were limited, which possibly indicates a subordinate role of temperature in microbial processes in North Sea sediments. Organic matter produced a direct response in bacterial production and oxygen consumption in mesocosms. Bacterial and protozoan abundance also increased. The effect of the organic input disappeared within 2 months and values of enhanced variables declined to initial levels. The organic matter enrichment in mesocosms apparently did not provide sufficient energy to keep the microbenthos active at field levels through summer.These results suggest that in the silty sediments in the field, organic matter is available for bacterial production throughout summer. In sandy sediments, the major organic matter input, which sets the seasonal pattern, appears to be in June. Apparently the seasonal development of microbial variables can be mimicked in mesocosms with organic matter supplies. Differences between the field and mesocosms are further illustrated by carbon budgets. Recycling of bacterial biomass was required to meet the bacterial carbon demand in the budget.Publication No. 22 of the project Applied Scientific Research Neth. Inst. for Sea Res. (BEWON).