Probabilistic methods for marine ecological risk assessment     

Schobben  H. P. M.; Scholten  M. C. Th. 《ICES Journal of Marine Science》1993,50(4):349-358

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Seasonal variation of zinc in the barnacle, Balanus balanoides (L.) maintained on a raft in the Menai Strait     

G. Walker  P. Foster 《Marine environmental research》1979,2(3):209-221

A population of the intertidal barnacle, Balanus balanoides (L.) maintained on a raft in the Menai Strait was sampled regularly over a two-year period and pooled fractions analysed for zinc and other trace metals. The seasonal variation of zinc in three fractions (body, other soft tissues and shell) has been followed and related to physiological condition. The body accumulates zinc almost continuously whilst this trace metal accumulates in the ovary only as it develops and is lost in the gametes when these are laid. The newly formed egg-masses therefore may be the more useful sample for indicating zinc pollution.  相似文献   

Feeding Habits of Ocinebrina edwardsi (Mollusca: Prosobranchia) a Common Mussel Drill of the Italian Coasts     

P. Tongiorgi    P. Nardi    L. Galleni    M. Nigro  U. Salghetti 《Marine Ecology》1981,2(2):169-180

Abstract. The shell-boring gastropod Ocinebrina edwardsi (PAYR.) lives associated with Mytilus galloprovincialis LMK on which it preys. Predation is preferentially directed towards small (< 15 mm long) mussels. The predation rate (number of mussels eaten per gastropod per day) for medium sized mussels (16–25 mm long) during a year ranges from 0.03 to 0.11. The predation rate is directly influenced by the sea-water temperature. Predation follows a seasonal cycle reaching a maximum in July and a minimum in January. O. edwardsi drills selectively the median anterior region of the mussel valve, close to the dorsal edge.  相似文献   

Investigation of a eutrophic tidal basin: part 1—factors affecting the distribution and biomass of macroalgae     

D. Lowthion  P. G. Soulsby  M. C. M. Houston 《Marine environmental research》1985,15(4):263-284

The distribution and biomass of macroalgae, principally Enteromorpha spp., have been estimated in Langstone Harbour, a 19 km² tidal basin in southenrn England. Comprehensive mapping was carried out annually at the time of maximum biomass and monthly mapping of selected areas allowed seasonal changes to be studied. Aerial false-colour photography and ground-level mapping were used for assessing the area and density of cover of macroalgae, but have identified no continuous trends between 1973 and 1982. In nine years, some 48% of the intertidal mudflat has supported >75% macroalgal cover at some stage, but generally only one-third of this potential has been achieved annually. The average peak biomass was determined by a stratified sampling method and varied about a mean of 38.5 g dry weight per square metre and showed significant annual differences. The processes controlling macroalgal growth and distribution reviewed, but, in general, factors other than nutrient availability are effective in determining areas supporting high macroalgal cover in any particular year.  相似文献   

Turbulent structure of the subsurface layer of the sea according to the data of the <Emphasis Type="Italic">Sigma-1</Emphasis> measuring complex     

A. M. Chukharev  V. A. Barabash  A. G. Zubov  O. I. Pavlenko 《Physical Oceanography》2007,17(2):75-87

We present the results of experimental investigations of the characteristics of turbulence in the layer of wave-induced mixing. The data on the fluctuations of velocity, temperature, and conductivity are obtained with the help of a Sigma-1 measuring complex. The computed values of the dissipation rate of turbulent energy are compared with different models proposed for the subsurface layer. It is shown that the available models fail to guarantee satisfactory agreement of the numerical results with the experimental data for the layer of active wave action and, in particular, in the presence of swell. This leads us to the conclusion concerning the necessity of parametrization and assimilation of more complete data on the state of the sea surface, the structure of currents, and the surface layer of the atmosphere in the models. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 15–28, March–April, 2007.  相似文献   

The CPR survey (1948–1997): a gridded database browser of plankton abundance in the North Sea     

L. Vezzulli  P. C. Reid 《Progress in Oceanography》2003,58(2-4):327

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The Structure of A Turbulent Jet in A Crossflow-Effect of Jet-Crossflow Velocity     

李行伟  匡翠萍  陈国谦 《中国海洋工程》2002,(1)

A comprehensive numerical study on the three-dimensional structure of a turbulent jet in crossflow is performed. The jet-to-crossflow velocity ratio (R) varies in the range of 2 - 16; both vertical jets and inclined jets without excess streamwise momentum are considered. The numerical results of the Standard two-equation k-ε model show that the turbulent structure can be broadly categorised according to the jet-to-crossflow velocity ratio. For strong to moderate jet discharges, i.e. R> 4, the jet is characterized by a longitudinal transition through a bent-over phase during which the jet becomes almost parallel with the main freestream, to a sectional vortex-pair flow with double concentration maxima; the computed flow details and scalar mixing characteristics can be described by self-similar relations beyond a dimensionless distance of around 20-60. The similarity coefficients are only weakly dependent on R. The cross-section scalar field is kidney-shaped and bifurcated, vvith distinct double concentr  相似文献   

On the application of the units of measurement of the amount and composition of matter in oceanology     

E. I. Ovsyanyi  V. I. Zaburdaev  A. S. Romanov 《Physical Oceanography》2004,14(4):243-254

We consider the procedures of conversion of the conventional and out-of-system units of measurement of the amount and composition of matter used in oceanology to the International System of Units (SI). The coefficients of conversion are presented in the form of a table. We present the data on the units of measurement of mineralization (scales of salinity) of seawater for the oceanic range of its variability, freshened waters of internal seas, and brines. The contemporary concept of salinity as a dimensionless quantity is discussed.Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 61–72, July–August, 2004.  相似文献   

Temperature of the ocean surface as an indicator of thermodynamic processes in the northwest Pacific     

G. A. Vlasova  A. M. Polyakova 《Physical Oceanography》2004,14(5):295-302

The numerical computations and analysis of the anomalies of temperature of the ocean surface in the northwest part of the Pacific Ocean were carried out on the basis of the archival data for 1960 and 1964–1985. A five-year period of general instability of the annual average temperature was revealed (1973–1977). In this period, the year 1974 was the coldest and the year 1977 was characterized as extremely warm. We performed the analysis of the interannual and annual variability of the anomalies of temperature of the ocean surface and revealed common features and distinctions of the seasonal evolution of these anomalies for years with substantially different temperature conditions. A quasistationary zone of maximally heated waters was discovered in the band located (independently of the year and season) between 36 and 46°N to the east of 140°E. This zone coincides in space with the zone of the subarctic front and the south part of the subarctic region. The influence of the meanders of the Kuroshio Current was demonstrated. It is shown that their activity increases after the events of El-Niño and, hence, the thermal energy of the water area considerably increases and remains elevated for a period of 1–2 yr after the indicated events.Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 45–52, September–October, 2004.This revised version was published online in May 2005 with corrections to cover date.  相似文献   

Structure of the mesoscale variability of the troposphere and stratosphere found from radio refraction measurements via CHAMP satellites     

N. M. Gavrilov 《Izvestiya Atmospheric and Oceanic Physics》2007,43(4):451-460

Data of an experiment on radio occultation sounding of the atmosphere with the use of GPS signals were used to obtain global distributions of the variances of mesoscale variations in the refractive index in the troposphere and stratosphere. The experiment was carried out with the CHAMP satellite during the period 2001–2005. Measured vertical profiles were smoothed inside 5–10-km-thick layers centered at different altitudes in the troposphere and stratosphere with the use of second-degree polynomials. Deviations from the smoothed quantities and the corresponding variances were obtained for each profile and averaged for each month during the analyzed interval of the CHAMP experiment. Altitude-longitude-latitude inhomogeneities in the distribution of refractive index variances were analyzed. Altitude and latitude distributions of maxima and minima of refractive index variances depend on altitude and season. Turbulence and acoustic gravity waves can be the causes of small-scale and mesoscale variations in the refractive index of the troposphere and stratosphere. The variances of variations in the refractive index are greater in the regions of tropospheric jet streams and in the zones of near-equatorial deep convection. Atmospheric disturbances increase over mountain systems.  相似文献