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1.
The correlation between the azooxantellate scleractinian coral distribution and the abundance of the zooplankton in the Atlantic Ocean is discussed. The analysis is based on a dataset of 943 specimens (82 species) sampled at 87 stations that were performed during the scientific cruises of Russian research vessels in the Atlantic. The hypothesis concerning if the coral biodiversity and population density correlate with the zooplankton abundance was tested. The relationships between these parameters are contradictory. High coral biodiversity and population density were registered for the areas of low and average zooplankton abundance in the surface waters.  相似文献   

2.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

3.
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   

4.
An analysis of the data of measurements of the fine structure and microstructure fluctuations of hydrophysical fields in the upper 200-m layer of the Black Sea carried out using CTD profilers and a Baklan free falling microstructure and turbulence profiler revealed the existence of a positive correlation between the intensity of the fine structure and microstructure fluctuations and the dynamics of the currents. On the other hand, the level of the fine structure and microstructure fluctuations reflects the rate of the vertical turbulent exchange. It was shown that, in the case of the absence of the Black Sea Rim Current (BSRC) jet or clearly manifested mesoscale eddy structures, the vertical turbulent exchange in the pycnocline is weak, while, in the opposite case, it is stronger. The results obtained support the supposition that the interbasin dynamics play an important role in the maintenance of the rate of small-scale mixing in the pycnocline and halocline and provide the vertical transport of dissolved oxygen from the cold intermediate layer into the deeper layers of the sea.  相似文献   

5.
为研究黄河入海径流变化条件下河口附近海域盐度扩散特征,以更好地保护河口海域生物资源多样性,本文以黄河下游利津水文站的长序列实测径流数据资料为基础,利用近海水动力模型FVCOM,分析径流变化对黄河口海域盐度的影响规律。结果表明:黄河口与莱州湾之间存在顺时针的环流系统,在余流作用以及涨落潮方向的影响下,黄河冲淡水长期向莱州湾扩散;丰水期黄河冲淡水几乎影响了整个莱州湾,27盐度锋可以到达莱州湾中部,27等盐线的表层包络面积为2 665.61 km2,占莱州湾的1/4左右,枯水期低盐度水只有向南扩散的趋势,27以下的低盐度水集中分布在黄河口门附近,27等盐线的表层包络面积只有199.65 km2;5月份,随着入海径流量增加,27等盐线扩散的范围、距离、方向都会发生明显变化。在对近海生物资源有迫切保护需求的情景下,适当减少其他用水户供水量以增加入海生态径流量,可以有效改善黄河口海域附近的盐度情况,为生物资源的生长繁殖创造良好条件。  相似文献   

6.
Variations of monsoon wind field in the sea area along the southeastern coast of China during the ENSO events and its influence on the sea level and sea surface temperature (SST) are explored mainly on the basis of the data of monthly mean wind at 850 hPa and five coastal stations during 1973-1987. The results from the analyses of the data and theoretical estimation show that the southwest wind anomalies appeared in the study area during the events, and northeast wind anomalies occurred in general before the events. With the coastline of the area being parallel basically to the direction of the wind, an Ekman transport will result in an accumulation of the water near the coast or a departure of the water from the coast. As a result , the sea level and SST there will be affected markedly. During the events, southwest wind will intensify in the summer, and northeast wind will weaken in the winter. Their total effect is that a large negative anomaly of the sea level and SST will occur. The estimations indi  相似文献   

7.
The potentiality of the nephelometric indication of the relationship of small and large particles in shallow waters is investigated using a submersible nephelometer. One of its channels measures the light scattered from the water at an angle of 90° in the blue spectrum, while the other does the same in the far red. The results of the field observations demonstrate differences in the vertical distributions of the signals of the channels supposedly due to the vertical variations in the ratio of the concentration of the small and large particles.  相似文献   

8.
According to Ocean Re-Analysis System 3 (ORA-S3) data, all components of the annual mean heat budget of the upper quasi-homogeneous ocean layer (UQL) in the North Atlantic for the period of 1959–2011 have been calculated and errors of these estimates have been determined. It has been shown that the contribution of the horizontal eddy diffusivity (estimated as a residual term of the UQL heat balance equation) to changes in the UQL annual mean temperature is significantly overestimated. This takes place mainly due to neglecting the covariances of seasonal fluctuations of current velocity vector components and UQL temperature gradients in calculations carried out with the use of annual average values. These covariances play an important role in the annual mean heat budget in some regions of the North Atlantic, especially in tropical latitudes. Changes in the annual average UQL temperature in the central and eastern parts of the North Atlantic are significantly affected by errors related to an inaccuracy of estimates of annual average heat fluxes on the ocean surface. The maximum contribution of the horizontal eddy diffusivity to the interannual variability of the UQL temperature is observed in the northwestern part of the North Atlantic and the region of the Subpolar Gyre.  相似文献   

9.
入海河口是河流和海洋生态系统的过渡带,陆源生态敏感因素入海将极大地影响近岸海域的生态状况。因此,入海生态敏感因素监测是海岸带生态保护和生态防灾减灾的重要基础,也是促进海洋经济可持续发展的关键一环。然而,当前我国入海河口生态预警监测系统的建立尚处于起步阶段,与发达国家之间还存在较大差距。文章从入海河口生态状况对海域生态系统健康的影响入手,总结了国内外入海河口海洋生态预警监测技术的发展历程、建设情况和应用方向,探讨了建设入海河口生态预警监测站的生态意义和系统发展方向。  相似文献   

10.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

11.
长江、黄河入海沉积物中元素组成的对比   总被引:3,自引:0,他引:3  
使用X射线荧光分析仪对取自长江大通站(包括部分南京段)和黄河利津站入海沉积物进行了分析,研究了25种元素的含量特征及它们在长江和黄河里的差异,并与前人研究成果作了比较.研究表明,长江、黄河中的沉积物存在较明显差异,黄河沉积物中明显富集Ca,Sr,Si等元素;长江沉积物中明显富集Al,Fe,Ti,Mn,Cu,Zn,Pb,Rb,P,V等元素.这与2条河流流域的地质背景、气候带特征、风化程度以及人为活动影响关系密切.与前人研究结果相比,2类沉积物中重金属元素的含量有明显增加的趋势,但是用Al标准化之后发现只有部分重金属元素含量有所增加.重金属的变化可能与近年来中国工业快速发展及两河流域污染物质的排放增加有关.  相似文献   

12.
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   

13.
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   

14.
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   

15.
辽宁近岸海域水质演化及对近海陆域生态水文格局的响应   总被引:4,自引:0,他引:4  
根据1991-2000年对辽宁省近岸海域水质的连续监测资料,采用秩相关系数法对辽宁近岸海域水质做了定量评估,结果表明,辽宁省近岸海域海水水质较差,主要污染物为无机氮、活性磷酸盐、石油类和Pb,2000年全省近海海域各类功能区水质总达标率仅为48.1%。秩相关系数趋势预测表明:除COD有下降趋势外,其他主要污染物均有逐年上升趋势,且无机氮的上升趋势最为显著。辽宁省在沿海改革开放的初期,沿海海域的水环境做出了相当大的牺牲:20世纪90年代的中后期水质有了明显的改善,陆域非点源污染对近岸海域水质污染的贡献较大;各主要污染物在各海域的变化不同。生物学指标整体上显示,大连海域和营口海域水质在枯水期要好于丰水期,表现出明显的季节变化。无机氮与石油类和COD呈现出正相关关系,COD与石汕类、活悱磷酸盐和Pb呈现出弱正相关关系,水质PCA结果进一步表明辽宁近海海域水质污染除工业污染外,近海陆域非点源污染对水质污染的贡献最大。生态水文参数的主成分分析(PCA)及与主要污染物的回归分析结果表明,近海海域水质演化受到近海陆域生态水文过程的影响较大,无机氮受到近海陆地水开发影响最大;活性磷酸盐、石油类受到水文过程因子的影响最大;COD和Pb受到农业开发活动的影响最大。建议在辽宁省海水质综合整治的过程中,要加强对近海陆域生态水文过程的调节,实施海陆一体化的综合治理模式。  相似文献   

16.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

17.
The circulation pattern and volume transports in the eastern Weddell Gyre are estimated on the basis of hydrographic data collected by R.V. Polarstern between 1989 and 1996. In the northeastern edge of the Weddell Gyre, eastward-flowing water masses from the Antarctic Circumpolar Current and the Weddell Sea converge. Due to the strong effect of topographic constraints on ocean currents in the weakly stratified waters of high latitudes, the wedge-like structure of the Southwest Indian Ridge can cause the convergence. The increased shear leads to instabilities of the current at the eastern end of the ridge, which produce an intense mesoscale eddy field between 15° and 30°E. In the eddies, water from the Weddell cold regime and the Antarctic Circumpolar Current waters mix and form the water masses of the Weddell warm regime. These waters are advected southward and flow towards the westward southern rim current, which is driven by the Antarctic eastwind band. Hence, there is not a continous flow from the northern to the southern rim, but a decay of the mean flow in the northeast and a reformation in the south. Volume transports across the Greenwich Meridian, estimated on the basis of a combined CTD/ADCP data set, result in an eastward flow of 61 Sv in the northern rim current and a westward return flow of 66 Sv in the southern part of the gyre. The transport is about twice as high as previous estimates between Kapp Norvegia and the northern tip of the Antarctic Pensinsula, indicating a significant gyre circulation north of 70°S.  相似文献   

18.
Particular features of the distribution of the transparency and particulate matter content, their variability, and their interdependence in the surface water layer (0–5 m) over the northwestern shelf and in the adjacent abyssal part of the Black Sea in the summer were considered on the basis of long-term simultaneous optical, biological, and hydrological observations (1979–1993). In the shelf regions with different river discharges and in the waters of the open part of the sea, the distributions of the transparency, the total particulate matter, and its organic components (organic carbon, nitrogen, and chlorophyll a), as well as the relative content of particulate organic carbon in the total amount of the particulate matter and the content of chlorophyll a in the particulate organic carbon, were considered. The distributions of the transparency and particulate matter and their dependence on the water dynamics are in good agreement. It was demonstrated that extreme anthropogenic eutrophication influences the western and northern coastal shelf areas. The water transparency and particulate organic matter distributions in the central shelf area subjected to the influence of transformed river water and the water properties of the southern part of the shelf, which is influenced by the waters of the open sea, were determined according to the particular structure of the phytoplankton, its abundance, and the processes of its production and destruction.  相似文献   

19.
The origin and the spreading of the shallow Mediterranean water core (Ms) in the Iberian basin is discussed with a quasi-synoptic hydrographic data set enhanced by chlorofluoromethane (CFM) measurements. Its characteristic density level is found to be σt = 27.4. Characterized by high temperature and CFM values, Ms enters the Iberian basin in the region of Cape St Vincent between depths of 500–750 dbar. A heat anomaly of >11.8 × 109 J m−2 is chosen as the boundary between the presence of Ms and the background field. The core is found in a tongue-like shape as well as in separate isolated eddies of both cyclonic and anticyclonic circulation. Using the optimum multiparameter analysis (Tomczak and Large, 1989, Journal of Geophysical Research, 94, 16141–16149), the North Atlantic Central Water (NACW), which mixes with the Mediterranean outflow to form Ms, turned out to be in the mean 1°C warmer and 0.11 saltier than in regions with minor Mediterranean influence. This points to the Gulf of Cadiz as the origin of Ms, where the Mediterranean oufflows is in contact with NACW of the appropriate characteristics.  相似文献   

20.
本文基于渤海南部各测站观测风和浪的资料,分析了本海域波候的区域性特征.大浪的季节性变化和地理分布及风浪随风速成长特征等也作了讨论.另外,还指出本海域中大浪区.这些结果可用于制定防灾措施的依据.  相似文献   

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