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1.
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
2.
Relationship between the path of the Kuroshio in the south of Japan and the path of the Kuroshio Extension in the east 总被引：2，自引：0，他引：2
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
3.
北太平洋副热带海洋环流强度异常对长江中下游夏季降水的影响 总被引：3，自引：0，他引：3
利用SODA资料和ECCO资料计算得到的北太平洋副热带海洋环流强度,和国家气候中心整编的中国160站逐月降水资料,结合NCEP/NCAR再分析资料和Hadley中心海表面温度资料,分析了1970－2007年海洋环流强度异常同期的大尺度大气环流异常特征及对中国东部夏季降水的影响。结果表明:海洋环流强度变化与长江中下游地区降水存在密切的反相关。环流强度异常可以通过影响西太平洋副热带高压的南北位置异常进而影响长江中下游降水。海洋环流偏弱时,副高位置偏南,长江中下游地区受气旋性环流异常影响,来自副高西北侧的强西南水汽输送至此,在该地区形成强水汽辐合中心,同时伴随上升运动加强和对流的加强,进一步导致该地区降水偏多;当海洋环流偏强时,西太平洋副高位置偏北,长江中下游地区受反气旋性环流异常影响,伴随辐散下沉及水汽辐散,导致该地区降水偏少;海洋环流强度异常导致的中纬度海区海表面温度异常,可能是导致副高南北位置异常的主要原因。 相似文献
4.
采用海洋再分析结果,研究了海洋涡旋和锋面波动对台湾以东黑潮锋的影响,结果表明,Rossby波第一斜压模态形成的冷涡(暖涡),减弱(增强)台湾以东黑潮温度锋强度,减小(加大)锋的宽度.在再分析结果中,捕获到1991年1-2月台湾以东的一次黑潮锋面波动.锋面波动的波槽(波脊)到达时,该温度锋强度减弱(增强),宽度和厚度减小... 相似文献
5.
利用1973-2016年日本西海水产研究所提供的日本鲐(Scomber Japanicus)对马群系的资源量与渔获量数据,结合产卵场1(SG1, 26°~31°N,122°~127°E)、产卵场2(SG2, 30°~35°N,128°~131°E)、索饵场(FG, 35°~38°N,127°~138°E)的海表面温度、太平洋年代际振荡指数(PDO)和Nino3.4区海表温距平值(SSTA),建立基于灰色系统的日本鲐对马群系资源丰度预测模型。灰色关联和相关系数分析结果显示:选择产卵场2的4月、9月海表面温度和索饵场4月海表面温度作为日本鲐资源丰度关键影响因子。建立的模型有:分别包含产卵场2的4月、9月和索饵场4月的海表面温度3个因子的GM(1,2),GM(1,3),GM(1,4)的7种模型。这7种模型的相对残差Q检验值分别为:0.131 0,0.140 2,0.145 9,0.149 3,0.176 7,0.140 3和0.173 5。结果表明,基于产卵场2的4月海表面温度所建立的GM(1,2)模型是对日本鲐对马群系资源丰度最优预测模型。 相似文献
6.
Satellite observations of the partial pressure of carbon dioxide in the surface water of the Huanghai Sea and the Bohai Sea 总被引：1，自引：0，他引：1
Based on 5 831 continuous in situ measurements of the partial pressure of carbon dioxide on the sea surface p(CO2),related parameters of the sea surface temperature(SST) and chlorophyll-a(Chl a) concentration in 2010 winter,spring and summer of the Huanghai Sea and the Bohai Sea,the inherent relations among them are investigated preliminarily.This study reveals that the seasonal variability of SST and Chl a concentration has a significant influence on p(CO2).The authors have proposed a new algorithm to estimate p(CO2) from SST and Chl a concentration measurements.Compared with the vessel data,the root mean square error(RMSE) of p(CO2) retrieved by using the new model is 13.45 μatm(1atm=101.325 kPa) and the relative error is less than 4%.Then,SST and Chl a concentration data observed by satellite are used to retrieve p(CO2) in the Huanghai Sea and the Bohai Sea;and a better accuracy can be obtained if the quality control for sea surface chlorophyll-a concentration observed by satellite is used.The RMSE of retrieved p(CO2) data with quality control and that without quality control are 15.82 μatm and 31.74 μatm,respectively. 相似文献
7.
The spatial distribution of physico-chemical parameters(sea surface temperature(SST), p H, sea surface salinity(SSS), dissolved oxygen(DO) and Secchi depth) along with filterable nutrients(dissolved inorganic nitrate(DIN),dissolved inorganic phosphate(DIP) and reactive silicate(DSi)) are measured in the winter months of November,December, January and February for four consecutive years from 2009–2010 to 2012–2013 on the shallow continental shelf(20 m bathymetry) of the coastal waters(up to 18 km away from shoreline) of the northern Bay of Bengal(n Bo B) during the highest high tide(HHT) and lowest low tide(LLT) hours for the first time. The variability of the coastal biogeochemical environment is assessed during the HHT and LLT hours and for this purpose, seawater samples are collected from seven different locations of a transect in the coastal region. Physicochemical parameters(except SST) show significant difference in magnitude during the HHT and LLT hours respectively. p H, SSS and DO are found to increase in the HHT hours and vice-versa. The data reveal that during the LLT hours, a relative increase of freshwater input in the n Bo B can have elevated the nutrient concentration compared with that observed during the HHT hours. The ratio of nutrient concentration is found to deviate significantly from the Redfield ratio. The abundance of DIP is much higher compared with that of DIN and DSi.The anthropogenic sources of DIP from the upstream flow(especially the domestic effluent of several metropolises) can be mainly attributed behind such an observation. In order to characterize and establish the trend of such variation in such an important bio-climatic region, long-term and systematic ecosystem monitoring in the coastal water of the n Bo B northern Bay of Bengal should be carried out throughout the year. 相似文献
8.
A study of the state of the Russian coastal marine ecosystems of the Sea of Japan (the Tumen River mouth) and the Sea of Okhotsk
(the eastern shelf of Sakhalin Island and the Sakhalin Gulf) and Kraternya Bight (Yankich Island, Kuril Islands) was carried
out during the 29th expedition of the R/V Akademik Oparin. A highly sensitive express analysis using the DNase of the Strongylocentrotus intermedius sea urchin was utilized in order to evaluate the quality of the natural marine water of the areas experiencing different
degrees of anthropogenic impact. The marine water quality was evaluated according to the degree of the DNase inhibition in
the samples. The presence of ecological stress was shown at the aforementioned sites excluding Kraternya Bight. The method
allows the fast (1 hour) analysis of the pollution of marine areas and, coupled with data on the hydrological, hydrochemical,
and microbiological studies of water samples, provides the possibility to make an ecological forecast. 相似文献
9.
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
10.
11.
Joan E. Cartes Manuel Hidalgo Vanesa Papiol Enric Massutí Joan Moranta 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(3):344-365
Short spatio–temporal variations in the feeding intensity and the diet of the European hake, Merluccius merluccius, together with the abundance of their potential prey were studied between August 2003 and June 2004 at two locations, northwest (Sóller) and south (Cabrera), off the island of Mallorca (Balearic Islands, Western Mediterranean) at depths between 150 and 750 m. The two areas present different oceanographic conditions. Hake was mainly distributed along the shelf-slope break and the upper slope (between 166 and 350 m) where recruits (TL<18 cm) were dominant. The hake's diet varied as a function of size. Recruits fed mainly on micronektonic prey, and the diet was influenced primarily by seasonality, with two dietary patterns (identified by MDS analyses) corresponding to August–September 2003 (summer) and to November 2003/February–April 2004 (autumn–winter). The summer pattern was consistent with a thermally stratified water column, while November and April were consistent with homogenized temperature and salinity throughout all the water column. The main prey of recruits were the euphausiid Meganyctiphanes norvegica and the midwater fish Maurolicus muelleri in autumn–winter and myctophids (mainly Ceratoscopelus maderensis) in summer. In contrast to recruits, the geographic factor (NW vs. S) was the main factor influencing the diets of post-recruits (TL between 18 and 21.9 cm) and adults (TL?22 cm). Hake recruits (and to a lesser extent post-recruits) and their preferred prey occupied different depth ranges during daylight periods. Meganyctiphanes norvegica and Ceratoscopelus maderensis were, for instance, distributed as much as 500 m deeper than hake that had eaten them. All these trends were especially obvious at NW, an area with a more abrupt slope and with a greater influence by northern winter intermediate water (WIW) inflow in early spring than the S area. These factors probably enhanced micronekton aggregation in April, when feeding intensity (stomach fullness) increased among recruits and post-recruits only at NW. All these factors may have a crucial role in the diet, distribution and probably recruitment success of small hake. Biological factors were also important in trophic shifts in the diet and feeding of hake. Multi-linear regression models pointed to a trend of higher fullness with higher hepato-somatic index (HSI). Therefore greater food consumption by hake may enhance its metabolic condition. Within the framework of shelf-break and slope ecology, we show how the ‘boundary’ mesopelagic community inhabiting the middle slope sustains the trophic requirements of hake, a species distributed at shallower depths along the shelf-slope break. Mesopelagic euphausiids and myctophids are often found in the diets of shelf-break fish. Because the boundary mesopelagic community is distributed worldwide, the high levels of fish biomass often found at shelf-slope breaks could be sustained trophically by deeper, offshore mesopelagic communities, an inverse energy transfer from deep to shallow-water marine ecosystems. 相似文献
12.
V. A. Ivanov S. P. Lyubartseva N. Mikhailova N. B. Shapiro 《Physical Oceanography》2001,11(6):509-524
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an
ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics
is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of
a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic
elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as
a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water
area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the
shelf zone and open sea.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
13.
The study of the Kuroshio in the East China Sea and the currents east of the Ryukyu Islands 总被引：3，自引：0，他引：3
In this study, the inverse method is used to compute the Kuroshio in the East China Sea and southeast of Kyushu and the currents east of the Ryukyu Islands, on the basis of hydrographic data obtained during September-October, 1987 by R/V Chofu Maru. The results show that: (1)A part of the Taiwan Warm Current has a tendency to converge to the shelf break; (2) the Kuroshio flows across the section C3 (PN) with a reduced current width, and the velocity of the Kuroshio at the section C3 increases and its maximum current speed is about 158 cm/s, and its volume transport here is about 26×106m3/s; (3) the Kuroshio has two current cores at the sections C3 (PN) and B2 (at the Tokara Strait); (4) the currents east of the Ryukyu Islands are found to flow northward over the Ryukyu Trench during September-October, 1987. The velocities of the currents are not strong throughout the depths. At the section C2 east of the Ryukyu Islands, the maximum current speed is at the 699 m levei and its magnitude is 25 cm/s, and i 相似文献
14.
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
15.
为了研究烟曲霉次生代谢产物,我们采用硅胶柱层析、sephadex LH-20凝胶柱层析、半制备液相色谱等分离方法对来源于印度洋深海区的烟曲霉(Aspergillus fumigatus)的乙醇提取液进行系统的次生代谢产物分离,根据所分离得到的化合物的理化性质和波谱数据确定化合物的结构。共分离鉴定了15个化合物,其中11个二酮哌嗪类生物碱(diketopiperazine),4个喹唑啉类衍生物(fumiquinazoline),分别为:fumitremorgin B(1),13-oxofumitremorgin B(2),fumitremorgin C(3),12-hydroxyfumitremorgin(13),3-hydroxyfumiquinazoline A(14)和fumiquinazoline E(15)。分离得到的15个化合物,丰富了烟曲霉次生代谢产物的类型,为烟曲霉的开发利用提供了化学研究基础。 相似文献
16.
I. E. Timchenko A. A. Primalenny V. D. Yarin E. F. Vasechkina E. M. Igumnova 《Physical Oceanography》2001,11(4):367-378
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of
the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption
(fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by
the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with
application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem,
which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge,
water exchange with the Black Sea, etc.).
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
17.
胶州湾海岸线历史变迁的分形分析 总被引：3，自引：0，他引：3
使用网格法以1987-2006年间5景经过精确校正的Landsat-TM遥感图像为基本资料,计算出了胶州湾海岸线的分形维数,其值为1.090 1(1987年),1.090 3(1992年),1.082 9(1997年),1.076 2(2003年)和1.080 1(2006年).结果表明,1987-2006年胶州湾海岸线分形维数先后经历了缓慢增大、减小、再增大的三个变化阶段.胶州湾较大规模的海岸工程是其岸线分形维数减小的主要原因,而较小规模的海岸工程和自然过程则是其分形维数增大的原因. 相似文献
18.
In this work, the history of the development of the Turali area (the Dagestan coast of the Caspian Sea) in the Late Holocene
is under consideration. The analysis of the geological structure of the bay bar that separates the Bolshoy Turali lagoon from
the sea, the granulometric analysis of the coastal deposits, and the data of geo-radar profiles make it possible to assert
that the large eolian relief forms were formed during the New Caspian (Novokaspiyskoe) transgression of the Caspian Sea. 相似文献
19.
We correct the diurnal data on precipitation obtained from the output of the global system of reanalysis as applied to the
observed daily amounts of precipitation at certain geographic points of the coastal region of the Black Sea. The estimations
of the actual amounts of precipitation are taken from the ECAD (European Climate Assessment and Dataset) database. We analyze
the amounts of precipitation for three winter months. As a working tool for the investigation of correlations between the
regular meteorological variables (predictors) taken from the reanalysis and the local amounts of precipitation at certain
geographic points (predictants), we use the method of artificial neural networks (ANN). A numerical criterion of adequacy
of the estimates of the daily amounts of precipitation performed according to reanalysis and the ANN method is proposed. By
using this criterion, we show that the efficiency of the ANN method in simulating precipitation is higher as compared with
the procedure of reanalysis.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 23–35, May–June, 2006. 相似文献