我国近海和邻近海的海洋环境对最近全球气候变化的响应

鉴于全球气候变暖对海洋环境和海洋生态及对经济和社会可持续发展影响的严重性,作者首先利用ERA-40再分析的风场资料以及HadISST和SODA等海洋高分辨率再分析资料,分析了近50年来全球气候变化对中国近海(包括渤海、黄海、东海和南海)和邻近海(主要是热带和副热带西太平洋)海面附近的风力、海表纬向和经向风应力和海表温度的影响。分析结果表明:由于受全球气候变暖的影响,1976年之后中国近海和邻近海上空的冬、夏季风变弱,从而引起中国近海冬、夏季海表风应力减弱(尤其是经向风应力),而海表水温明显上升;并且,冬、夏季海表风应力的减弱和海水温度的上升在中国东海反映尤其明显,这些为中国近海赤潮的频繁发生提供了有利的海洋环境。此外,从中国近海上空环流散度分布的变化可见,中国近海上空从1976年之后大气环流辐散增强,这不利于中国近海上升流的形成,从而会对沿岸水域营养盐的输送产生影响。

厦门港及邻近海域水螅水母类、管水母类和栉水母类的生态研究

本文根据1980年9月-1981年8月在厦门港及邻近海域逐月定量采集浮游动物样品的周年资料,分析了水螅水母类、管水母类和栉水母类的种类组成,季节变化和平面分布,并扼要介绍了优势种单囊杯水母、拟细浅室水母和球型侧腕水母的分布状况,结果表明,水母种类的季节变化周年有一个高峰;总个体数的周年变化有1个高峰和两个次高峰,根据水母的生态特点,调查海区的水母可分为河口性、近岸性和大洋广暖水性等生态类群,它们的演替在一定程度上可反映出不同水系的强度。

Phytoplankton in Prydz Bay and Its Adjacent Sea Area of Antarctica During the Austral Summer (1998/1999)

The cell density, species composition and distribution of phytoplankton, and their relations to environmental factors in Prydz Bay and its adjacent sea area, Antarctica (69degrees-77degrees E, 62degrees-70degrees S) during the austral summer of 1998/1999 were investigated. A total of 48 taxa belonging to 21 genera of phytoplankton in the sea area were identified. The average cell density of phytoplankton was 22.46 x 10(3) cells/dm(3), of which diatoms were predominant (84.51%). The highest cell density of phytoplankton occurred in Prydz Bay and the adjacent continental shelf where the average cell density was 46.03 x 10(3) cells/dm(3). The lowest cell density (3.34 x 10(3) cells/dm(3)) occurred in deep sea area. The dominant species of phytoplankton was Fragilariopsis curta. The vertical distribution of phytoplankton density was highest in the upper part of 0-50 in depth, lower in 100 in and lowest in 150 in. The species composition and cell density of phytoplankton were influenced by water circulation. The cell density was positively correlated with water temperature and salinity, and negatively correlated with the concentration of nutrients.

Numerical Study on Tides in the Taiwan Strait and its Adjacent Areas

Diurnal and semi-diurnal tides in the Taiwan Strait and its adjacent areas are calculated by using a two-dimensional finite-difference model. Compared with data of more than 20 observation stations around the Taiwan Strait, the model-produced results agree quite well with those of previous researches using observational data from coastal tidal gauge stations. According to the results, the co-tidal and co-range charts are given. Furthermore, the characteristics of 8 major tidal constituents have been uminated respectively. The result shows that： （1） The tide motion can be attributed to the interaction between the degenerative rotary tidal system in the north and the progressive tidal system in the south. （2） The southward and northward tidal waves of semi-diurnal tide converge in the middle of the Taiwan Strait while the diurnal tidal waves propagate southwestward through the Taiwan Strait and the Luzon Strait. （3） The maximum amplitude of semi-diurnal tides exists at the area between the Meizhou Bay and Xinghua Bay, and that of diurnal tides appears in the region to the east of the Leizhou Peninsula, （4） The patterns of co-tidal and co-range charts of N2, K2 and P1, Q1 tidal constituents are similar to those of M2, S2 and K1 O1 tidat constituents, respectively

Late Cenozoic Tectonic Deformation in the Dongsha Islands and Adjacent Sea Area

Dongsha Island and the adjacent sea area locate at the northern continental margin of the South China Sea (SCS), and is connected to the east by the Manila Trench. Analyses of seismic stratigraphy and gravity, magnetic and drilling wells data led to the discovery of three post fault sequences (V, VI, VII). Extensive tectonic uplift, magma activity and erosion occurred in Dongsha Island and the adjacent area, where most of the faults in the northeastern SCS were still active during Pliocene and Quaternary. Two groups of faults trending NEE and NW were developed during Late Cenozoic. We conclude that three important tectonic movements, especially Dongsha movement (4.4-5.2 Ma) and Liuhua movement (1.4-1.89 Ma), controlled the structural framework in the Dongsha rise; whose deformation in the east is stronger than that in the west and whose stress field variation suggests that the tectonic uplift in the study area contributed to magmato tectonic events correlated to the main collision phases between the East China and Taiwan 5-3 and 3-0 Ma ago.

Fog Detection over China's Adjacent Sea Area by using the MTSAT Geostationary Satellite Data

A fog threshold method for the detection of sea fog from Multi-function Transport Satellite (MTSAT1R) infrared (IR) channel data is presented.This method uses principle component analysis (PCA),texture analysis,and threshold detection to extract sea fog information.A heavy sea fog episode that occurred over China's adjacent sea area during 7 8 April 2008 was detected,indicating that the fog threshold method can effectively detect sea fog areas nearly 24 hours a day.MTSAT-1R data from March 2006,June 2007,and April 2008 were processed using the fog threshold method,and sea fog coverage information was compared with the meteorological observation report data from ships.The hit rate,miss rate,and false alarm rate of sea fog detection were 66.1%,27.3%,and 33.9%,respectively.The results show that the fog threshold method can detect the formation,evolution,and dissipation of sea fog events over period of time and that the method has superior temporal and spatial resolution relative to conventional ship observations.In addition,through MTSAT-1R data processing and a statistical analysis of sea fog coverage information for the period from 2006 to 2009,the monthly mean sea fog day frequency,spatial distribution and seasonal variation characteristics of sea fog over China's adjacent sea area were obtained.

Characteristics of the δ15NNO3 distribution and its drivers in the Changjiang River estuary and adjacent waters

In this study, we conducted investigations in the Changjiang （Yangtze） River estuary and adjacent waters （CREAW） in June and November of 2014. We collected water samples from different depths to analyze the nitrogen isotopic compositions of nitrate, nutrient concentrations （including inorganic N, P, and Si）, and other physical and biological parameters, along with the vertical distribution and seasonal variations of these parameters. The compositions of nitrogen isotope in nitrate were measured with the denitrifier method. Results show that the Changjiang River diluted water （CDW） was the main factor affecting the shallow waters （above 10 m） of the CREAW, and CDW tended to influence the northern areas in June and the southern areas in November. 615Nrqo~ values in CDW ranged from 3.21%o-3.55%o. In contrast, the deep waters （below 30 m） were affected by the subsurface water of the Kuroshio Current, which intruded into the waters near 3 I^N in June. The ~iI^NNo3 values of these waters were 6.03%0-7.6%0, slightly higher than the values of the Kuroshio Current. Nitrate assimilation by phytoplankton in the shallow waters of the study area varied seasonally. Because of the favorable temperature and nutrient conditions in June, abundant phytoplankton growth resulted in harmful algae blooms （HABs）. Therefore, nitrate assimilation was strong in June and weak in November. The ~15NNo3 fractionations caused by assimilation of phytoplankton were 4.57%0 and 4.41%o in the shallow waters in June and November, respectively. These results are consistent with previous laboratory cultures and in situ investigations. Nitrification processes were observed in some deep waters of the study area, and they were more apparent in November than in June. The fractionation values of nitrification ranged from 24%0-25%o, which agrees with results for Nitrosospira tenuis reported by previous studies.

Molecular Characterization of Sulfate-Reducing Bacteria Community in Surface Sediments from the Adjacent Area of Changjiang Estuary

Sulfate-reducing bacteria(SRB),which obtain energy from dissimilatory sulfate reduction,play a vital role in the carbon and sulfur cycles.The dissimilatory sulfite reductase(Dsr),catalyzing the last step in the sulfate reduction pathway,has been found in all known SRB that have been tested so far.In this study,the diversity of SRB was investigated in the surface sediments from the adjacent area of Changjiang Estuary by PCR amplification,cloning and sequencing of the dissimilatory sulfite reductase beta subunit gene(dsr B).Based on dsr B clone libraries constructed in this study,diversified SRB were found,represented by 173 unique OTUs.Certain cloned sequences were associated with Desulfobacteraceae,Desulfobulbaceae,and a large fraction(60%) of novel sequences that have deeply branched groups in the dsr B tree,indicating that novel SRB inhabit the surface sediments.In addition,correlations of the SRB assemblages with environmental factors were analyzed by the linear model-based redundancy analysis(RDA).The result revealed that temperature,salinity and the content of TOC were most closely correlated with the SRB communities.More information on SRB community was obtained by applying the utility of Uni Frac to published dsr B gene sequences from this study and other 9 different kinds of marine environments.The results demonstrated that there were highly similar SRB genotypes in the marine and estuarine sediments,and that geographic positions and environmental factors influenced the SRB community distribution.

Seasonal Changes in Phytoplankton Biomass and Dominant Species in the Changjiang River Estuary and Adjacent Seas:General Trends Based on Field Survey Data 1959-2009

The characteristics of seasonal variation in phytoplankton biomass and dominant species in the Changjiang River Estuary and adjacent seas were discussed based on field investigation data from 1959 to 2009. The field data from 1981 to 2004 showed that the Chlorophyll-a concentration in surface seawater was between 0.4 and 8.5 ktg dm-3. The seasonal changes generally presented a bimodal trend, with the biomass peaks occurring in May and August, and Chlorophyll-a concentration was the lowest in winter. Seasonal biomass changes were mainly controlled by temperature and nutrient levels. From the end of autumn to the next early spring, phytoplankton biomass was mainly influenced by temperature, and in other seasons, nutrient level （including the nutrient supply from the terrestrial runoffs） was the major influence factor. Field investigation data from 1959 to 2009 demonstrated that dia- toms were the main phytoplankton in this area, and Skeletonerna costatum, Pseudo-nitzschia pungens, Coscinodiscus oculus-iridis, Thalassinoema nitzschioides, Paralia sulcata, Chaetoceros lorenzianus, Chaetoceros curvisetus, and Prorocentrum donghaiense Lu were common dominant species. The seasonal variations in major dominant phytoplankton species presented the following trends： 1） Skeletonema （mainly S. costatum） was dominant throughout the year; and 2） seasonal succession trends were Coscinodiscus （spring） →Chaetoceros （summer and autumn） → Coscinodiscus （winter）. The annual dominance of S. costatum was attributed to its environmental eurytopicity and long standing time in surface waters. The seasonal succession of Coscinodiscus and Chaetoceros was associated with the seasonal variation in water stability and nutrient level in this area. On the other hand, long-term field data also indicated obvious interannual variation of phytoplankton biomass and community structure in the Changjiang River Estuary and adjacent seas： average annual phytoplankton biomass and dinoflagellate proportion both presented increased trends during the 1950s - 2000s.

Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters

Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters were analyzed based on data from bottom trawl surveys conducted on the R/V Beidou in June, August and October 2006. Four fish assemblages were identified in each survey using two-way indicator species analysis (TWIA). High fish biomass was found in the northern part, central part and coastal waters of the survey area; in contrast, high fish diversity was found in the southern part of the survey area and the Changjiang estuary outer waters. Therefore, it is difficult to maintain high fishery production when high fish diversity is evenly distributed in the fish community. Fish became smaller and fish size spectra tended to be narrower because of fish species variations and differences in growth characteristics. Fish diversity increased, the age to maturity was reduced and some migrant species were not collected in the surveys. Fish with low economic value, small size, simple age structure and low tropic level were predominant in fish assemblages in the Changjiang estuary and its adjacent waters. The lowest hypoxic value decreased in the Changjiang estuary and its adjacent waters.

Spatial Distribution and Controlling Factors of Sedimentary Bodies in Jiaozhou Bay and Adjacent Sea Areas, Qingdao

The distributions of thickness of unconsolidated Quaternary sedimentary layers in Jiaozhou Bay and Qingdao offshore area were studied by using 1079-km high-resolution shallow seismic profiles and drilling core data, and the factors controlling the Quaternary evolution were discussed. The results show that such thickness distributions resulted from the coactions of geologic structures and marine hydrodynamic conditions since the Holocene. The geologic structures controlled the slope deposit, proluvial and fluvial fillings since the late Pleistocene. Holocene marine hydrodynamics eroded away sediments at the bay mouth, and tides carried these eroded materials to the sides of the bay mouth and released them there, forming channel-ridge-alternating geomorphic features. During transgressive processes, the sea level rose rapidly, and insufficient sediment supply and tidal actions yielded the relict sediments in the east of Qingdao offshore area.

Nutrient fluxes in the Changjiang River estuary and adjacent waters——a modified box model approach

To solve nutrient flux and budget among waters with distinct salinity difference for water-salt- nutrient budget, a traditional method is to build a stoichiometrically linked steady state model. However, the traditional way cannot cope appropriately with those without distinct salinity difference that parallel to coastline or in a complex current system, as the results would be highly affected by box division in time and space, such as the Changjiang （Yangtze） River estuary （CRE） and adjacent waters （30.75°-31.75°N, 122°10′-123°20′E）. Therefore, we developed a hydrodynamic box model based on the traditional way and the regional oceanic modeling system model （ROMS）. Using data from four cruises in 2005, horizontal, vertical and boundary nutrient fluxes were calculated in the hydrodynamic box model, in which flux fields and the major controlling factors were studied. Results show that the nutrient flux varied greatly in season and space. Water flux outweighs the nutrient concentration in horizontal flux, and upwelling flux outweighs upward diffusion flux in vertical direction （upwelling flux and upward diffusion flux regions overlap largely all the year）. Vertical flux in spring and summer are much greater than that in autumn and winter. The maximum vertical flux for DIP （dissolved inorganic phosphate） occurs in summer. Additional to the fluxes of the ChanNiang River discharge, coastal currents, the Taiwan Warm Current, and the upwelling, nutrient flux inflow from the southern Yellow Sea and outflow southward are found crucial to nutrient budgets of the study area. Horizontal nutrient flux is controlled by physical dilution and confined to coastal waters with a little into the open seas. The study area acts as a conveyer transferring nutrients from the Yellow Sea to the East China Sea in the whole year. In addition, vertical nutrient flux in spring and summer is a main source of DIP. Therefore, the hydrodynamic ROMS-based box model is superior to the traditional one in estimating nutrient fluxes in a complicated hydrodynamic current system and provides a modified box model approach to material flux research.

Taxonomic Distinctness of Macrofauna as an Ecological Indicator in Laizhou Bay and Adjacent Waters

In this paper, we assessed the ecological and biodiversity status in the Bohai Sea through a quantitative survey on mac-rofaunal community at 25 stations in Laizhou Bay and adjacent waters in the autumn of 2006.We tested the robustness and effectiveness of taxonomic distinctness as an ecological indictor by analyzing its correlation with species richness and natural environmental variables and by analyzing other ecological indicators (Shannon-Wiener H' and W statistics from Abundance Biomass Comparison curve).Results so obtained indicated that the benthic environment of the study waters in general is not under major impact of anthropogenic disturbance, but some stations in Laizhou Bay and along the coast of the Shandong Peninsula and even in the central Bohai Sea might be moderately disturbed and showed signs of ecological degradation.The taxonomic distinctness measures △+ and Λ+ were independent of sampling effort and natural environment factors and were compliant to other ecological indicators.Further application of the taxonomic distinctness indicator to assess marine biodiversity and ecosystem health on a larger regional scale with historical data seems promising.

Thermal Regime of the Crust of the Eastern Black Sea and Adjacent Territory

In the models to create a representation of the internal structure of the Earth, the distribution thicknesses of the layers, density and pressure is usually clearly shown while the idea of the distribution of temperature in them is extremely vague. Without any doubt, this is very important information that temperature should play a significant role in all of these models. In the presented work, the results of studying of a heat flow distribution and calculations of temperatures of the crust of the Eastern Black Sea water area and adjoining territory are given. The distribution of a heat flow is made on the basis of the experimental data and also on the basis of the calculated flow values. Temperature calculation was performed by solving the heat equation. Study region was covered with equal-step grid and in its node bedding depths of boundary surfaces are known. The temperature calculations were performed at the nodes of the lattice at the bottom of the sedimentary complex, and at the border of Conrad and Moho. The calculations take into account the dependence of the coefficient of thermal conductivity of rocks on temperature.

Carbon pools and fluxes in the China Seas and adjacent oceans

The China Seas include the South China Sea, East China Sea, Yellow Sea, and Bohai Sea. Located off the Northwestern Pacific margin, covering 4700000 km^2 from tropical to northern temperate zones, and including a variety of continental margins/basins and depths, the China Seas provide typical cases for carbon budget studies. The South China Sea being a deep basin and part of the Western Pacific Warm Pool is characterized by oceanic features; the East China Sea with a wide continental shelf, enormous terrestrial discharges and open margins to the West Pacific, is featured by strong cross-shelf materials transport; the Yellow Sea is featured by the confluence of cold and warm waters; and the Bohai Sea is a shallow semiclosed gulf with strong impacts of human activities. Three large rivers, the Yangtze River, Yellow River, and Pearl River, flow into the East China Sea, the Bohai Sea, and the South China Sea, respectively. The Kuroshio Current at the outer margin of the Chinese continental shelf is one of the two major western boundary currents of the world oceans and its strength and position directly affect the regional climate of China. These characteristics make the China Seas a typical case of marginal seas to study carbon storage and fluxes. This paper systematically analyzes the literature data on the carbon pools and fluxes of the Bohai Sea,Yellow Sea, East China Sea, and South China Sea, including different interfaces(land-sea, sea-air, sediment-water, and marginal sea-open ocean) and different ecosystems(mangroves, wetland, seagrass beds, macroalgae mariculture, coral reefs, euphotic zones, and water column). Among the four seas, the Bohai Sea and South China Sea are acting as CO_2 sources, releasing about0.22 and 13.86–33.60 Tg C yr^(-1) into the atmosphere, respectively, whereas the Yellow Sea and East China Sea are acting as carbon sinks, absorbing about 1.15 and 6.92–23.30 Tg C yr^(-1) of atmospheric CO_2, respectively. Overall, if only the CO_2 exchange at the sea-air interface is considered, the Chinese marginal seas appear to be a source of atmospheric CO_2, with a net release of 6.01–9.33 Tg C yr^(-1), mainly from the inputs of rivers and adjacent oceans. The riverine dissolved inorganic carbon (DIC) input into the Bohai Sea and Yellow Sea, East China Sea, and South China Sea are 5.04, 14.60, and 40.14 Tg C yr^(-1),respectively. The DIC input from adjacent oceans is as high as 144.81 Tg C yr^(-1), significantly exceeding the carbon released from the seas to the atmosphere. In terms of output, the depositional fluxes of organic carbon in the Bohai Sea, Yellow Sea, East China Sea, and South China Sea are 2.00, 3.60, 7.40, and 5.92 Tg C yr^(-1), respectively. The fluxes of organic carbon from the East China Sea and South China Sea to the adjacent oceans are 15.25–36.70 and 43.93 Tg C yr^(-1), respectively. The annual carbon storage of mangroves, wetlands, and seagrass in Chinese coastal waters is 0.36–1.75 Tg C yr^(-1), with a dissolved organic carbon(DOC) output from seagrass beds of up to 0.59 Tg C yr^(-1). Removable organic carbon flux by Chinese macroalgae mariculture account for 0.68 Tg C yr^(-1) and the associated POC depositional and DOC releasing fluxes are 0.14 and 0.82 Tg C yr^(-1), respectively. Thus, in total, the annual output of organic carbon, which is mainly DOC, in the China Seas is 81.72–104.56 Tg C yr^(-1). The DOC efflux from the East China Sea to the adjacent oceans is 15.00–35.00 Tg C yr^(-1). The DOC efflux from the South China Sea is 31.39 Tg C yr^(-1). Although the marginal China Seas seem to be a source of atmospheric CO_2 based on the CO_2 flux at the sea-air interface, the combined effects of the riverine input in the area, oceanic input, depositional export,and microbial carbon pump(DOC conversion and output) indicate that the China Seas represent an important carbon storage area.

Dissolved barium as a tracer of Kuroshio incursion in the Kuroshio region east of Taiwan Island and the adjacent East China Sea

From May to June 2014, the geochemical characteristics of dissolved barium(Ba) in sea water and its influx from the Kuroshio into the East China Sea(ECS) were studied by investigation of the Kuroshio mainstream east of Taiwan Island and the adjacent ECS. This allowed for the scope and extent of the Kuroshio incursion to be quantitatively described for the first time by using Ba as a tracer. The concentration of Ba in the Kuroshio mainstream increased gradually downward from the surface in the range 4.91–19.2 μg L.1. In the surface layer of the ECS, the Ba concentration was highest in coastal water and gradually decreased seaward, while it was higher in coastal and offshore water but lowest in middle shelf for bottom layer. The influx of Ba from Kuroshio into the ECS during May to October was calculated to be 2.19×108 kg by a water exchange model, in which the subsurface layer had the largest portion. The distribution of Ba indicated that Kuroshio upwelled in the sea area northeast of Taiwan Island. The north-flowing water in the Taiwan Strait restrained the incursion of Kuroshio surface water onto the ECS shelf, while Kuroshio subsurface water gradually affected the bottom of the ECS from outside. The results of end member calculation, using Ba as a parameter, showed that the Kuroshio surface water had little impact on the ECS, while the Kuroshio subsurface water formed an intrusion current by climbing northwest along the bottom of the middle shelf from the sea area northeast of Taiwan Island into the Qiantang Estuary, of which the volume of Kuroshio water was nearly 65%. Kuroshio water was the predominant part of the water on the outer shelf bottom and its proportion in areas deeper than the 100 m isobath could reach more than 95%. In the DH9 section(north of Taiwan Island), Kuroshio subsurface water intruded westward along the bottom from the shelf edge and then rose upward(in lower proportion). Kuroshio water accounted for 95% of the ocean volume could reach as far as 122°E. Ba was able to provide detailed tracing of the Kuroshio incursion into the ECS owing to its geochemical characteristics and became an effective tracer for revealing quantitative interactions between the Kuroshio and the ECS.