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1.
This paper analyses the global tendency of the sea level rise (SLR) and its long term influence on the sea level upstream drainage cascade based on the example of the level’s variation in the Vistula Lagoon of the Baltic Sea compared to the other lagoons and coastal regions of the southeastern part of the Baltic Sea. A steady positive trend in the water level variations was revealed; its magnitude varies significantly depending on the time period. In general, during the 100–150 year period, the rate of the SLR in the lagoons and coastal areas of the Baltic Sea (1.7–1.8 mm per year) is close to the SLR rate in the World Ocean. In the second half of the 20th century, the increased rate of the SLR in the lagoons and marine areas became stronger (up to 3.6 mm per year in the Vistula Lagoon and in 1959–2006 in the sea and exceeded the rate of global ocean SLR). It dramatically increased at the end of the last century both in the lagoons and in the sea (up to 10.0–15.0 mm per year). This is the response not only to the global climate warming but it is likely that it is also a response to the changes of the climate driving forces that influence the regimes of the local wind and precipitation in the catchment.  相似文献   

2.
1Introduction Besidestheprecipitationandriverdischarges,the watersinthePacificOceanandtheAtlanticOceanare thesourcesoftheArcticOceanwater.TheAtlantic waterenterstheArcticOceanviatheFramStraitand theBarentsSea.Foritsdenserfeatureduetohigh salinity,mostofitsinkstothenorthofSvaldbardand circulatesinallthedeepbasinsintheArcticOcean, formingthedeepandbottomwatersoftheArcticO- cean(Aagaardetal.,1985;Rudelsetal.,1999).The BeringStraitistheonlychannelforthePacificwater toflowintotheArcticOce…  相似文献   

3.
1 古新-下渐新统含油气层系 古新-始新统母岩形成于滨海和湖泊沉积环境中,并在大量冲积源的参与之下,促进了含分散有机质混合类型砂-黏土质陆源岩层的堆积。在中国东北诸盆地中,含工业油气的白垩-早第三纪建造形成于开阔的浅水和深水湖泊环境中。与中国的盆地类似,在下第三系下部  相似文献   

4.
Izvestiya, Atmospheric and Oceanic Physics - The Great Andaman–Sumatra earthquake (GASE) on December 26, 2004, with magnitude Mw of 9.2, occurred in the Indian Ocean near the northwestern...  相似文献   

5.
Data on the contents and compositions of the hydrocarbons (HCs)—aliphatic (AHCs) and polycyclic aromatic (PAHs)—are provided in comparison with the contents of the total organic carbon (Corg), the lipids in the particulates, and the Corg in bottom sediments. Particular attention has been paid to the distribution of the HCs in the water area of the Kravtsov oil field. It has been established that the concentrations of AHCs in the water are governed by the content of particulates, and the elevated AHC concentrations are confined to the coastal areas. In the water area of platform D-6, the sandy bottom sediments were notable for the great variability of the HC concentrations, both laterally and from year to year. In the summer of 2010, the content of AHCs averaged 40 μg/g (19% in the Corg), and that of PAHs, 23 ng/g. Natural seepage from the sediment mass is considered to be a source of HCs along with oil contamination.  相似文献   

6.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

7.
A. A. Maximov 《Oceanology》2006,46(2):185-191
The data on the bottom concentrations of dissolved oxygen in the eastern part of the Gulf of Finland obtained in 1923–1939 and in 1962–1989 were analyzed. No statistically reliable differences were found between the two periods studied. It was found that, during the 20th century, the fluctuations in the oxygen concentration were caused by the interannual variability of the winter severity and water salinity. A strong oxygen deficit in the summer was recorded after cold winters, when early freezing suppressed the vertical mixing, and/or in the years of a significant inflow of salt waters from the Baltic Sea with low oxygen contents. It is likely that the long-term dynamics of the oxygen concentration near the bottom in the open parts of the bay is determined by the large-scale variability of the hydrometeorological parameters.  相似文献   

8.
The role of the small-size (SF; 0.1–0.5 mm) and large-size (LF; 0.5–20.0 mm) fractions in the biomass and abundance of mesozooplankton (0.1–20.0 mm) was assessed using the database of samples obtained during the cruises of RV Akvanavt in the northeastern Black Sea in November 2000 and October 2006. The mesozooplankton was collected by means of Juday nets (37/50, filtering gauze 160 μm) and Niskin bottles in two areas: (1) the shelf and continental slope (30–1480 m depth) and (2) the deep sea (depths of more than 1500 m). The plankton net was considerably less effective in collecting the SF of the mesozooplankton (by a factor of 30–36) than the Niskin bottles. When comparing the SF and LF, we estimated the abundance and biomass of the SF in the samples obtained with the Niskin bottles. The abundance of the SF in the deep-sea area was 2.5 times lower compared to the shelf and continental slope, and the LF abundance was 5.0 times lower in the same way. The abundance of the SF constituted 88% of the total mesozooplankton on the shelf and continental slope, and 78% in the deep-sea area. The biomass of the SF was higher as well on the shelf and continental slope. Meroplankton played a significant role in the SF zooplankton abundance (0.5 × 103 + 0.16 ind. m−3) in this area. The SF grazing impact was 10% of the total mesozooplankton grazing on the shelf and continental slope, and 17% in the deepsea area. Appendicularia and nauplii of copepods had the greatest contribution to the mesozooplankton grazing among the SF group.  相似文献   

9.
10.
Using the data of long-term simultaneous optical, biological, and hydrological observations (1980–1993), particular features of the horizontal distribution of the transparency and the total particulate matter content and the contents of its organic components (organic carbon and nitrogen and chlorophyll a) and their variability in the surface water layer (0–5m) over the northwestern shelf and the adjacent abyssal part of the Black Sea in the autumn season are considered. The detritus/phytoplankton ratio in the particulate organic matter and their relative contents in the total particulate matter are calculated. The distributions of the transparency and particulate matter content were found to be in good agreement and both depend on the water dynamics. It was established that, during the period of the abrupt growth in the Black Sea water turbidity (in the early 1990s), a significant decrease in the transparency and an increase in the particulate matter content caused by the production-destruction processes were observed only in the central and southern regions of the sea.  相似文献   

11.
This paper presents an evaluation of the effectiveness of the regulatory regime in the management of oil pollution on Kenya's marine and coastal environment. The prospect of chronic oil pollution along the Kenyan coastline and the port of Mombasa is discussed. A review of the vulnerable marine and coastal resources, commonly used indicators of effectiveness in oil pollution management and the legislation governing oil pollution is given. The author concludes by emphasising that despite having the right legislation in place, there is need for the establishment of criteria and indicators necessary for evaluation of policy effectiveness.  相似文献   

12.
近30年来莱州湾滨海湿地景观格局变化特征研究   总被引:1,自引:0,他引:1  
基于莱州湾滨海湿地特征以及野外实地观测数据,利用landsat遥感影像手段,揭示1990-2018年莱州湾滨海湿地景观格局变化特征,并结合景观指数分析莱州湾滨海湿地异质性。结果表明,1990-2018年间,莱州湾滨海湿地呈现人工滨海湿地面积增加而天然滨海湿地面积减少的趋势。截至2018年莱州湾滨海湿地面积总计1954 km2,其中天然滨海湿地面积约811 km2,人工滨海湿地面积约1143 km2,分别占42%和58%,滨海湿地向建设用地转化的趋势明显。斑块数量(NP)、景观形状指数(LSI)等景观指数值逐年增加,表明莱州湾景观格局变化明显且破碎化程度加重。莱州湾滨海湿地不同岸段之间景观格局变化的驱动机制不完全一样,造成其破碎化程度加重的自然驱动力有河口冲淤、降水量变化等;人工驱动力主要为城市建设、港口码头、集约用海区建设、养殖业和制盐业的开发利用等。以期对莱州湾滨海湿地生态系统退化原因、合理利用和优化土地空间布局、采取有效措施保护及恢复滨海湿地提供一定的技术支持。  相似文献   

13.
1 IntroductionTheBeringStrait, with them aximum depth lessthan 60 m , isthe uniquepassagebetween the ArcticOcean and the North Pacific Ocean, and links twoshelfseas:theBeringSeainthesouthandtheChukchiSea in the north. The background flow field oftheBering…  相似文献   

14.
According to the results of the comparative study performed of the littoral sediments sampled in small inlets of Kandalaksha Bay (the White Sea in the Russian Arctic), the metals (Fe, Mn, Cu, Zn, Pb, Cr, and Li) occur mainly in a biogeochemical-stable mineral-incorporated form, which comprises 77–99% of the total metal content. The ratio of the liable form, which is easily extracted by a weak acid, is on average 3.2% for the total Fe, 2.0% for Mn, 1.7% for Cr, 5.6% for Pb, 5.8% for Zn, 6.5% for Cu, and is negligible for Li. The concentrations of the most studied trace metals are below the threshold level according to the environmental quality guidelines (the sediment analysis). The ratio of the metal forms evidences the natural origin of the elevated concentrations of both Zn and Cr in the sediments.  相似文献   

15.
16.
A numerical experiment on the reproduction of the variability in the state of North Atlantic water in 1948–2007 with a spatial resolution of 0.25° has been performed using the global ocean model developed at Institute of Numerical Mathematics, Russian Academy of Sciences (INM RAS), and the Shirshov Institute of Oceanology (IO RAS) (the INM–IO model). The data on the state of the atmosphere, radiation fluxes, and bulk formulas of the CORE-II protocol are used as boundary conditions. Five successive 60-year calculation cycles have been performed in order to obtain the quasi-equilibrium state of a model ocean. For the last 20 years, the main elements of large-scale ocean circulation have been analyzed and compared with the WOA09 atlas data and the results of other models.  相似文献   

17.
红树林生态系统小型底栖动物研究进展   总被引:1,自引:0,他引:1  
刘均玲  黄勃 《海洋科学》2012,36(10):118-122
  相似文献   

18.
本文基于南大洋环流研究最新资料,从资料来源、动力模式以及有待解决的问题几个方面较详细地阐述南大洋环流动力学研究动态。  相似文献   

19.
深海原生动物多样性研究进展   总被引:2,自引:0,他引:2  
陈旭淼  徐奎栋 《海洋科学》2014,38(10):119-126
<正>1引言原生动物是一大类单细胞真核生物的统称,其中自由生活的主要类群包括异养鞭毛虫、纤毛虫和肉足虫(有孔虫和放射虫为代表);它们是生物圈中数量最为庞大的吞噬营养类群,部分种类具有内共生藻类或功能性叶绿体而进行兼性营养。在水环境中,不论是浮游或是底栖生活的原生动物,其生命过程与水体和底质的环境存在着密切的联系;并且通过各种营养关系与其他生物共同联结成为一个有机整体。同时,原生动物的基础研究也为探索真核生  相似文献   

20.
The data for the present study were collected at 20 sampling stations in the Kara Sea along the transect from the Ob estuary to the deep sea St. Anna Trough in September 2007. Based on the hydrophysical features, the distribution of the Chl a, and the primary production, we distinguished six habitats: the river, estuary, inner and outer shelf, continental slope, and trough. The impact of the small-size (<0.5 mm) and large-size (>0.5 mm) fractions of the zooplankton on the phytoplankton’s organic carbon in the different regions of the Kara Sea was estimated. The ingestion rate was assessed using the analysis of the gut fluorescence content and the gut evacuation rate. The zooplankton grazed 1–2% of the phytoplankton biomass in the river and estuary; 3.5% over the shelf; and 6 and 10% in the regions of the trough and slope, respectively. The grazing impact of the small-sized zooplankton increased from the river zone to the deep regions (from 1 to 90%) along with their share in the total zooplankton abundance (from 18 to 95%). From 72 to 86% of the primary production was grazed over the shelf and slope. The primary production did not cover the feeding requirements of the zooplankton in the estuarine regions and St. Anna Trough in the autumn. In the estuarine regions, the major portion of the organic matter settles on the bottom due to the strong inflow of the allochthonous matter and the relatively low zooplankton grazing.  相似文献   

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