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1.
以水族馆内圈养的北海狮为研究对象,利用长达29 h的连续被动声学观测数据,对北海狮水下声信号类型进行了研究。共检测出22 689个水下声信号,对时长、最小频率、最大频率和峰值频率这4个声学参数采用聚类分析方法将信号分为10种类型:单脉冲(SP)、哨声(WS)、咕咕声(GG)、咚咚声(DS)、狗吠声(BK)、吼叫声(WY)、嗡嗡声(BZ)、撞击声(BG)、单频声(SF)以及咩咩声(BT)。该分类方式涵盖了北海狮92.6%的水下发声。北海狮水下声信号时长的均值为5~1 244 ms,峰值频率一般小于10 kHz。10种类型信号的占比各有不同,BK,BT和BG信号的比例较高;SP,WS和BZ信号的比例次之;DS,WY,SF和GG信号的比例较低。对北海狮水下声信号类型的分析能帮助了解北海狮的声行为特征,对野外北海狮的声学观测具有重要的指导价值。 相似文献
2.
The structure of the reproductive gathering of beluga whales (RG) was studied near Cape Beluzhii in the Solovetsky Islands
in the White Sea by the photo identification of individuals in 2007–2008; in addition, the peculiarities of the seasonal and
interseasonal dynamics of the RG incomings were analyzed. The gathering is formed by predominantly females and calves of different
ages, which visit the RG area as stable “family” groups. About 15% of the observed females come to Beluzhii Cape every year
and stay there during the whole summer season; thus, forming the regular part of the RG. The other animals come there for
a certain time period, which is probably preconditioned by their physiological readiness for coupling and procreation for
some of the females. When comparing our data with the catalogue of the visually registered beluga whales’ markers (1996–2008),
we found that most of the identified animals of the Solovetsky RG appear here during one summer season or even with an off
period of several years despite the significantly regular findings of most of them for this area. We conclude this may be
linked with the natural changes of the individual markers due both to the shedding and the sexual cycle in the mature animals.
Our data allow concluding that the total population of the Solovetsky PG is higher than was reported before using the visual
supervision methods. 相似文献
3.
A. K. Ambrosimov D. A. Ambrosimov P. N. Makkaveev Yu. R. Nalbandov L. E. Skibinskii P. V. Hlebopashev 《Oceanology》2009,49(5):630-642
Characteristics of different types of river drainage were obtained during studies of a polygon in the near-mouth part of the
Volga River in 2000–2003: “fast” (flowing through deep channels) and “slow” (that which passes through the littoral parts
of the delta (1–2 m)). The low current velocities (lower than in the channel waters by a factor of ten), the abundance of
water vegetation, and the strong heating of the waters lead to the high intensity of the biochemical processes. Therefore,
the chemical composition of the waters is subjected to significant transformation with intensity so high that it allows comparing
these regions with some sort of “bioreactor.” These changes influence the dissolved oxygen and various forms of carbon content. 相似文献
4.
5.
A proxy named “upwelling age”, defined as the ratio of wind time scale to “advection time”, was developed to quantify the
local tendency for coastal upwelling. The formulation of the “advection time” was derived from Ekman theory. A 3D numerical
model was used to validate and refine the theoretical formula by simulating a total of 30 cases of different bottom topographies
and wind stresses. The results agree reasonably well with the theoretical formulation although some modifications are necessary.
The final formulation of the “advection time” was parameterized as a function of pycnocline depth, bottom slope, and wind
stress. 相似文献
6.
Based on the scatterometer QuickScat wind data and the water-leaving radiances from the ocean color scanner SeaWiFS data for
2000–2004, we composed a pair of mean annual images of a testing site in the South Caspian Sea under conditions of west-bound
and east-bound winds corresponding to the offset and onset state of the shallows in the east of the testing site. It was established
that both the “offset” and “onset” radiances grow shorewards, but the former becomes about twice as large as the latter in
the middle of the shallows with 10–15 m of water, while their difference tends to zero at the seaward and coastal boundaries
of the shallow. These and other findings are hypothetically attributable to the inclination of the sea floor of the shallows,
due to which the surfacing of bottom sediments resuspended by the drift current takes less time under the “offset” wind conditions
than under the “onset” ones. The study’s results indicate that the effect of the bottom sediments resuspension upon the structure
of the images of the marine shallows is universal in character and needs to be taken into account to improve the bio-optical
algorithms for estimating the admixtures in the thickness of the shallows from the satellite data. 相似文献
7.
A. S. Samodurov V. Z. Dykman V. A. Barabash O. I. Efremov A. G. Zubov O. I. Pavlenko A. M. Chukharev 《Physical Oceanography》2005,15(5):311-322
We describe a new measuring complex aimed at the investigation of small-scale processes in the upper active layer of the sea.
The necessity of creation of a complex of this sort is justified and a circle of problems that can be solved with the help
of this complex is described. The scales of resolution of horizontal and vertical inhomogeneities in measuring in the mode
of vertical probing are theoretically estimated. The basic technical characteristics of the complex are presented. We also
present the results of laboratory and field tests, which confirm the agreement between the calculated and actual technical
possibilities of the complex. The structural features of various versions of the “Sigma-1” measuring complex (the “Sigma-1P”
point-to-point-operation version and the “Sigma-1Z” probing version) are described.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 60–71, September–October, 2005. 相似文献
8.
There has been a long-standing debate concerning how dangerous seismic surveys are with respect to marine life. Marine seismic
work today is dominated by airgun technology, where high energy is generated by a release of compressed air into the water.
The objective of the “Time coded impulse seismic technique” project is to examine whether a new low energy acoustic source
can be used for seismic purposes. If the method turns out to be successful, the low output energy and continuous operation
will make the source suitable in environmental sensitive areas. The Low level Acoustic Combustion Source (LACS) is a petrol
driven pulsed underwater acoustic source. It operates at a few meters depth, and each shot can be digitally controlled from
the surface by a computer located in the mother vessel. A presentation of the recorded LACS signal characteristics, the modulation,
the Pseudo Noise coding/decoding principles and field test results, is given. The importance of using an optimized code with
fine resolution and of using the near field recording as a correlator sequence is demonstrated. Clear correlation peaks could
then be seen from the bottom and sub bottom reflectors. 相似文献
9.
A. Baltzer B. Tessier H. Nouzé R. Bates C. Moore D. Menier 《Marine Geophysical Researches》2005,26(2-4):235-245
The presence of gas is a common feature in many seismic sections. However, the origin of the gas is often difficult to determine.
Recently acquired very high resolution seismic profiles using an IKB Seistec boomer provide useful insight to the understanding
of the gas origins in a range of environmental settings including sea lochs and coastal lagoons. The gas features are described
both from a qualitative point of view through their acoustic facies, and quantitatively through the associated seismic signal
(polarisation, amplitude). Acoustic facies include acoustic turbidity, gas “curtains” and “blankets” as well as “white fringes”
and “black shadows”. All the features encountered have been related to specific gas nature generated by different sources
(organic matter degradation in paleo-valley infillings, waste material effluent). 相似文献
10.
During the Dives Nos. 409, 410, 480 and 481 of the Japanese submersible Shinkai 2000, conducted on June 10 and 11, 1989 and on May 16 and 17, 1990, several hydrothermal vents and prosperous vent associated
biological communities were found on the northern slope of the Iheya Ridge in the Mid-Okinawa Trough (27°32.5′ N, 126°58.5′
E: depth 1,400 m). The first site we found, the “Calyptogena Site”, was characterized by a relatively thick blanket of sediments, pleated and/or laminated lava flows, with occasional
lobate pillows and white and yellow stains. Although no remarkable shimmering water and thermal anomalies were detected during
the observations, the extraordinarily dense community must be related to hydrothermal activities. The community was dominated
by the giant white clam, Calyptogena okutanii, in biomass, and by Neolepas-type primitive scalpellids and slender vestimentiferan tube-worms in number. The second site, the “Pyramid Site”, situated
only 200 m northward from the Calyptogena Site has typical clear smokers emitting hot water over 200°C, and is characterized by a hard substratum of volcanic rocks
and hydrothermal slabs. No noteworthy succession was perceived at the Calyptogena Site over a year. Many of the vent members occurred at both sites. However, Calyptogena okutanii, which were confined to the sediment bottom, Neolepas spp. and larger vestimentiferan tube-worms were found to thrive only at the Calyptogena Site, being only minor elements in the Pyramid Site. The global distribution of several groups of organisms is discussed
preliminarily in zoogeographical terms based on comparison with other submersible missions and surveys done by surface vessels.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
11.
We executed investigations of Mediterranean lenses detection in the Atlantic using data recorded by buoys-profilers of the
“Argo” project (more than 11200 profiles). We investigate the region from 28° to 47° N and from 7° to 27° W for the period
from 2001 to 2010. From these data, we revealed “lenses profiles” with the salinity values exceeding 36 psu (2043 cases).
We demonstrate the allocation of Argo buoys in the area investigated and indicate their working periods; we also show the
periodicity of the “lenses profiles.” It was found out that the Argo buoys traced individual lenses and depicted correctly
their movements, the vertical scale of the eddy, its location in the depth, and the hydrological peculiarities of the lenses.
We estimated the number of lenses occurring in different periods and analyzed the interaction of the Argo buoy with the intrathermocline
lenses. The importance of these investigations for studying the Mediterranean water dynamics was pointed out. 相似文献
12.
The sedimentary infill of the Bay of Biscay off Ireland, UK, France and Spain took place in four phases. The last one (35 Ma to present) is characterised by gravitational, pelagic, contouritic and glacigenic processes leading to the setup of three deep sea systems. To the North, the Celtic and Armorican fans are fed by a “canyon-dominated” margin and its connection with the “Manche” palaeoriver, which drained a large area of western Europe. To the South, the Cap-Ferret fan results from the evolution of a “tectonic-dominated” margin and the erosion of the Pyrenee mountains. 相似文献
13.
A. S. Samodurov 《Physical Oceanography》2009,19(1):13-21
We make an attempt to answer the following question: how a natural stationary system formed by a layer and an interface “selects”
a unique set of governing parameters from a great number of possible collections under the conditions of double-diffusion
layer convection (e.g., for the bottom boundary layer in the Black Sea)? As the “rule of selection,” we use the principle
of minimum entropy production for systems close to the state of thermodynamic equilibrium. In the process of solution of the
problem, the system is regarded as a heat engine. The proposed approach is reduced to a simple procedure of application of
the principle of minimum entropy production to the analyzed case. The combined analysis of the theoretical results, the data
of deepwater field measurements in the Black Sea, and the results of laboratory experiments leads us to the conclusion that,
most likely, the stationary system “selects” its governing parameters according to the Prigogine–Glansdorff principle. The
density ratio (approximately equal to three for the stationary case) proves to be the key parameter of the system.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 16–25, January–February, 2009. 相似文献
14.
E. B. Shibanov 《Physical Oceanography》2005,15(3):192-202
We study the problem of the choice of initial approximation for the reflection and transmission coefficients in numerical
methods based on the principle of “interaction.” The disadvantages of the approximation of single scattering are demonstrated
and the regularities of propagation of light in media with strongly anisotropic scattering are analyzed. Semianalytic expressions
proposed for the evaluation of the initial approximation enable one to determine the characteristics of the light field in
plane-parallel media with relative errors of about 10−5 within the framework of the algorithm of “adding” of layers.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 62–72, May–June, 2005. 相似文献
15.
《Marine environmental research》1999,47(1):1-15
Brain, liver and muscle samples from seven male beluga whales, Delphinapterus leucas, from Hendrickson Island in the Canadian Arctic (n=3) and the St. Lawrence River estuary (n=4), were analyzed for polychlorinated biphenyls (PCBs) and other organochlorine (OC) compounds to determine whether there are differences in the distribution of these contaminants in beluga tissues and between geographic locations. Wet weight concentrations of ΣPCB, ΣDDT, Σchlordane and mirex were significantly higher (p<0.05) in St. Lawrence samples. Principal component analysis (PCA) of the PCB and OC data indicated that contaminant profiles in belugas from the St. Lawrence reflect point-source inputs of these compounds while Arctic samples appear to be dominated by PCB congeners and OC compounds subject to long-range transport and deposition. Discriminant functions analysis of the contaminant data for the brain, liver and muscle tissues indicated that the distributions of OC compounds in the liver and muscle tissues were very similar, while brain samples could be distinguished from other tissues by differences in PCB congener patterns and higher concentrations of Σhexachlorocyclohexane (ΣHCH), primarily αHCH. 相似文献
16.
E. L. Vinogradova P. N. Makkaveev Z. G. Melnikova Yu. R. Nalbandov P. A. Stunzhas P. V. Khlebopashev 《Oceanology》2011,51(5):796-803
The Volga River discharge consists of the waters transferred by fast currents through channels and the waters which are passing
through the shallow areas of the delta overgrown by cane. Using the hydrochemical data, it is possible to track distribution
of the waters modified by “biofilters” of macrophytes in the delta shallows starting from the external edge of the delta.
The main distinctive features of these waters are the high content of dissolved oxygen, the abnormally high values of the
pH, and the low content of dissolved inorganic carbon (both total and as CO2). These waters extend in the shape of 1 to 3-km-wide strips at a distance of 20–40 km from the outer border of the delta.
The analysis of the data obtained during the expeditions run by the Institute of Oceanology of the Russian Academy of Sciences
in 2003–2009, along with archived and published data, show that such “modified” waters occur almost constantly along the outer
edge of the Volga River delta. 相似文献
17.
Biological Responses to Seasonally Varying Fluxes of Organic Matter to the Ocean Floor: A Review 总被引：8，自引：0，他引：8
Andrew J. Gooday 《Journal of Oceanography》2002,58(2):305-332
Deep-sea benthic ecosystems are sustained largely by organic matter settling from the euphotic zone. These fluxes usually
have a more or less well-defined seasonal component, often with two peaks, one in spring/early summer, the other later in
the year. Long time-series datasets suggest that inter-annual variability in the intensity, timing and composition of flux
maxima is normal. The settling material may form a deposit of “phytodetritus” on the deep-seafloor. These deposits, which
are most common in temperate and high latitude regions, particularly the North Atlantic, evoke a response by the benthic biota.
Much of our knowledge of these responses comes from a few time-series programmes, which suggest that the nature of the response
varies in different oceanographic settings. In particular, there are contrasts between seasonal processes in oligotrophic,
central oceanic areas and those along eutrophic continental margins. In the former, it is mainly “small organisms” (bacteria
and protozoans) that respond to pulsed inputs. Initial responses are biochemical (e.g. secretion of bacterial exoenzymes)
and any biomass increases are time lagged. Increased metabolic activity of small organisms probably leads to seasonal fluctuations
in sediment community oxygen consumption, reported mainly in the North Pacific. Metazoan meiofauna are generally less responsive
than protozoans (foraminifera), although seasonal increases in abundance and body size have been reported. Measurable population
responses by macrofauna and megafauna are less common and confined largely to continental margins. In addition, seasonally
synchronised reproduction and larval settlement occur in some larger animals, again mainly in continental margin settings.
Although seasonal benthic responses to pulsed food inputs are apparently widespread on the ocean floor, they are not ubiquitous.
Most deep-sea species are not seasonal breeders and there are probably large areas, particularly at abyssal depths, where
biological process rates are fairly uniform over time. As with other aspects of deep-sea ecology, temporal processes cannot
be encapsulated by a single paradigm. Further long time-series studies are needed to understand better the nature and extent
of seasonality in deep-sea benthic ecosystems.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
18.
O. V. Krivenko 《Physical Oceanography》2006,16(6):337-349
Based on the experimental data obtained in 1990–1993 by the method of isotopic tracers with the help of a stable isotope of
nitrogen (15N), we establish basic regularities of the formation of “new” and regeneration production in the Black Sea and reveal the
factors specifying their combination. It is shown that the rates of nitrate and ammonium uptake by microplankton vary from
the minimum values in winter to the maximum values in summer. In the surface layer, the uptake of nitrates corresponding to
the amount of “new” production in deep-water layers is equal to ∼ 50% (in winter) and ∼ 30% (in summer) of the total uptake
of inorganic nitrogen compounds by microplankton. In the zone of photosynthesis, the average fractions of nitrates are equal
to 31 ± 10% in winter and 41 ± 10% in summer. The minimum values of this parameter are attained in the middle of spring and
in autumn. The fraction of “new” production (f-ratio) and the integral content of nitrates in the zone of photosynthesis are connected by a hyperbolic dependence. The period
of cyclic transformations of nitrates in this zone decreases from several dozens of days at the beginning of winter to 12
h in the mid-spring. In summer, this period is equal, on the average, to one day. The average period of cyclic transformations
of ammonium is equal to 15 ± 4 h in winter and 5 ± 3 h in summer.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 29–43, November–December, 2006. 相似文献
19.
An improved method of two-dimensional kinematical structural analysis of tides (the “method of the orbits”) is presented.
This method allows us to determine the parameters of the primary tidal waves shaping the observed tidal structure. The construction
of the vertical orbits for the individual tidal harmonics is performed along the horizontal coordinate axes; one of them is
oriented along the so-called “reactive azimuth,” which coincides with the direction of the tidal current at the instant of
the zero tidal level. In this case, the orbit parameters include information on the amplitude-phase relations of the interfering
waves and allow us to determine the angle of the waves crossing. The suggested method enables us to quantitatively describe
the mechanism of the tidal formation with oblique interference both close to the shore and in the open sea. We tested the
new method in two local zones of the White Sea (Morzhovets Island and in the vicinity of the entrance to Kandalaksha Gulf)
where the presence of rotating semidiurnal tidal currents evidences the significant role of oblique interference of tidal
waves. In these zones, the developed method made it possible to perform a detailed quantitative analysis of the local tide
structure caused by the M2 tidal wave, which plays the dominant role in the White Sea. The result describes the structure of the propagation of the
primary tidal waves better than the field of “pure” energy fluxes that was used earlier. 相似文献
20.
The processes underlying the development of the Kuroshio large meanders that occurred in 1986 and 1989 are investigated using
a satellite SST data set and hydrographic data. In both processes visible on the satellite SST images, a round-shaped, lower
SST region with a diameter of about 200 km is found to the east of the Kuroshio small “trigger” meander (Solomon, 1978) until
the region became extinguished near theEnshu Nada. The lower SST region can be interpreted as an anti cyclonic eddy, mainly because of the existence of a warm water mass in
the subsurface layer of this region. The warm water mass is characterized by a constant temperature of 18–19°C, the maximum
thickness of which is about 400 m. The satellite images show that the eddy is closely related to the Kuroshio path transforming
into a shape like the letter “S”. This means that the eddy plays an important role in the development of the Kuroshio large
meander since this, too, tends to follow an “S”-shaped path. Added to this, the subsurface layer structure of the eddy is
similar to that of the warm water mass offShikoku. This similarity, together with the eddy behavior visible on the satellite SST images, implies that the examined eddy corresponds
to the warm water mass offShikoku. In other words, the warm water mass offShikoku can be advected near to theEnshu Nada when the Kuroshio large meander occurs. 相似文献