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451.
M. F. Barker 《新西兰海洋与淡水研究杂志》2013,47(1):139-158
The larval stages of the acorn barnacles Chamaesipho columna, Chamaesipho brunnea, Elminius plicatus, Elminius modestus, Balanus trigonus, and Tetraclita purpurascens are described from larvae reared in the laboratory. A key and a table are included for separating larval stages and species. Skeletonema costatum appears to have a wide application as a food in the rearing of larvae of the Balanidae. The two Chamaesipho species show typical chthamalid characters of hispid antennal setae and unilobed labrum. The similarity between the larvae of Elminius plicatus and Tetraclita purpurascens supports the classification of E. plicatus as a tetraclitid. 相似文献
452.
B. F. Webb 《新西兰海洋与淡水研究杂志》2013,47(1-2):206-207
On 4 January 1971 a solitary specimen of the broadbilled swordfish Xiphias gladius Linneaus (Osteichthyes: Xiphiidae) was shot in Croisilles Harbour (41° 04’ S, 173° 40’ E). This was the first time the species has been recorded in the Tasman Bay area. 相似文献
453.
G. G. Matishov M. V. Nabozhenko I. V. Shokhin A. E. Zolotareva N. I. Bulysheva V. L. Semin V. V. Polshin V. V. Povazhnyi R. E. Verbitskyi E. V. Verbitskyi F. V. Sapozhnikov V. A. Spiridonov A. K. Zalota 《Oceanology》2013,53(3):374-376
The shelf zones of the Black Sea, Taman Bay, and the Sea of Azov are currently subjected to gross load related to the impact of invasive species, large-scale construction activities near the coast, intensive recreation activity, water pollution in large cities and ports, active navigation, unreasonable coastal arrangement, and dam construction. Another factor substantially affecting the composition of bottom sediments and, thus, the benthos environment is the terrigenous material carried by rivers in the course of catastrophic overflows. An example is the Kubansk flood in 2012, which significantly affected the sea coast near Novorossiysk, Gelendzhik, and Divnomorsk. The intensive onshore dumping results in the delivery of abundant allochthonous material, bottom silting causing changes in the dominants in the benthos associations, a decrease in the photic layer and the death of the phytobenthos, and also debris formation at the bottom. Debris can play the role of artificial reefs contributory for the formation of periphytic biocoenoses. 相似文献
454.
对虾传染性肌肉坏死病(infectious myonecrosis,IMN)最初于2002年8月爆发于巴西Piaui州的凡纳滨对虾(Litopenaeus vannamei)养殖场,并很快在巴西东北沿岸蔓延开来,目前已传至亚洲.2004年,经美国亚利桑那大学(University of Arizona)水产病害实验室研究,该病为一种新的对虾疾病,根据其症状,暂定名为传染性肌肉坏死病. 相似文献
455.
The experimental investigation of the run-up of periodic internal waves in a two-layer fluid on the coastal slope is performed
in an open hydrochannel at the Physical Department of the Lomonosov Moscow State University. The waves are produced by a wave
generator. We study the transformation of waves, the vertical structure of the field of velocities of mass transfer, and the
behavior of the parameters of internal waves propagating over the sloping bottom. It is shown that the run-up and breaking
of internal waves are accompanied by periodic emissions of portions of the heavier fluid from the bottom layer upward along
the slope. The Stokes drift velocity changes its sign as a function of depth. Moreover, both the wave length (the horizontal
distance between the neighboring crests) and the height of waves over the sloping bottom (the elevation of the crest over
the slope along the vertical) decrease as the wave approaches the coast. 相似文献
456.
F. Sardà J.B. Company N. Bahamón G. Rotllant M.M. Flexas J.D. Sánchez D. Zúñiga J. Coenjaerts D. Orellana G. Jordà J. Puigdefábregas A. Sánchez-Vidal A. Calafat D. Martín M. Espino 《Progress in Oceanography》2009,82(4):227-238
We performed a multidisciplinary study characterizing the relationships between hydrodynamic conditions (currents and water masses) and the presence and abundance of the deep-water rose shrimp Aristeus antennatus in a submarine canyon (Blanes canyon in the NW Mediterranean Sea). This species is heavily commercially exploited and is the main target species of a bottom trawl fishery. Seasonal fluctuations in landings are attributed to spatio-temporal movements by this species associated with submarine canyons in the study area. Despite the economic importance of this species and the decreases in catches in the area in recent years, few studies have provided significant insight into the environmental conditions driving shrimp distribution. We therefore measured daily A. antennatus catches over the course of an entire year and analyzed this time series in terms of daily average temperature, salinity, mean kinetic energy (MKE), and eddy kinetic energy (EKE) values using generalized additive models and decision trees. A. antennatus was captured between 600 and 900 m in the Blanes canyon, depths that include Levantine Intermediate Water (LIW) and the underlying Western Mediterranean Deep Water (WMDW). The greatest catches were associated with relatively salty waters (38.5–38.6), low MKE values (6 and 9 cm2 s−2) and moderate EKE values (10 and 20 cm2 s−2). Deep-water rose shrimp occurrence appears to be driven in a non-linear manner by environmental conditions including local temperature. A. antennatus appears to prefer relatively salty (LIW) waters and low currents (MKE) with moderate variability (EKE). 相似文献
457.
I. G. Granberg V. F. Kramar R. D. Kuznetsov O. G. Chkhetiani M. A. Kallistratova S. N. Kulichkov M. S. Artamonova D. D. Kuznetsov V. G. Perepelkin V. V. Perepelkin F. A. Pogarskii 《Izvestiya Atmospheric and Oceanic Physics》2009,45(5):541-548
The studies conducted in 1991–2004 by scientists of the A.M. Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences, and the Karpov Institute of Physical Chemistry yielded data on the structures of the surface air layer (to a height of 20 m) and both subinversion and inversion layers (to heights of from 800 m to 1 km), where arid aerosol is transported. One of the main objectives of the 2007 experiment was to record the space-vortex structures within a layer of 30–700 m that directly provide the removal and long-range transport of fine-dispersed (<5 µm) desert aerosol. This paper describes the organization of the Khar-Gzyr 2007 experiment (Black Lands, 2007) to study the convective removal of arid aerosol from desertificated lands, and it presents some data obtained from the remote sensing of the atmospheric boundary layer with a sodar network in the course of this experiment. The sodar network, which was developed to study a spatial structure of coherent vortices, included three identical minisodars (with carrier frequencies of 3.8 kHz) located at the apices of a triangle, each side of which was about 3.5 km, and a sodar (with a carrier frequency of 1.7 kHz). The vertical profiles of the three wind-velocity components and the characteristics of air temperature fluctuations were determined. The procedure of identifying coherent vortex structures is described. The variations in the vertical and horizontal wind-velocity components and the scales characteristic of such structures are estimated. 相似文献
458.
F. Rodriguez Monreal H.J. Villar R. Baudino D. Delpino S. Zencich 《Marine and Petroleum Geology》2009
In the Altiplanicie del Payún area (Neuquen Basin, Argentina), immature source rock sections intruded by up to 600 m thick Tertiary laccoliths show full spectrum maturity aureoles over hundreds of meters from the contacts. Commercial oil accumulations (20–33°API) and oil shows are located along the entire column, both in sandstone/carbonate and fractured igneous reservoirs. A challenging numerical model that included the emplacement of the intrusive bodies, with extreme temperature ranges and unusually short calculation time steps, has been done with the aim to better understand hydrocarbon generation and migration processes related to these thermal anomalies. 相似文献
459.
T. Feseker T. Pape K. Wallmann S.A. Klapp F. Schmidt-Schierhorn G. Bohrmann 《Marine and Petroleum Geology》2009
The sediment temperature distribution at mud volcanoes provides insights into their activity and into the occurrence of gas hydrates. If ambient pressure and temperature conditions are close to the limits of the gas hydrate stability field, the sediment temperature distribution not only limits the occurrence of gas hydrates, but is itself influenced by heat production and consumption related to the formation and dissociation of gas hydrates. Located in the Sorokin Trough in the northern Black Sea, the Dvurechenskii mud volcano (DMV) was in the focus of detailed investigations during the M72/2 and M73/3a cruises of the German R/V Meteor and the ROV Quest 4000 m in February and March 2007. A large number of in-situ sediment temperature measurements were conducted from the ROV and with a sensor-equipped gravity corer. Gas hydrates were sampled in pressurized cores using a dynamic autoclave piston corer (DAPC). The thermal structure of the DMV suggests a regime of fluid flow at rates decreasing from the summit towards the edges of the mud volcano, accompanied by intermittent mud expulsion at the summit. Modeled gas hydrate dissociation temperatures reveal that the gas hydrates at the DMV are very close to the stability limits. Changes in heat flow due to variable seepage rates probably do not result in changes in sediment temperature but are compensated by gas hydrate dissociation and formation. 相似文献
460.