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821.
We present a model of the processes of development in the ecosystem of the coastal zone of the sea constructed by the method
of adaptive balance of causes (ABC-method). The model contains nine variables (phyto- and zooplankton, fish larvae, fishes, oxygen, carbon dioxide, salinity,
biogenic elements, and detritus) affected by the solar radiation, surface wind, sea temperature, and river discharge. The
equations of the model contain control agents governing the dependences of the elements of the food chain on the vitally important
resources and environmental conditions. The scenarios of the processes of development are constructed for the simulated annual
courses of external actions. The possibility of management of fish resources by regulating the flows of biogenic elements
and detritus with river discharge is discussed. A mechanism of management based on the monitoring of the concentration of
dissolved oxygen in seawater is proposed. The numerical experiments show that the ABC-model of the processes of development in the ecosystem of the coastal zone of the sea makes it possible to simulate the scenarios
of regulation of the flows of biogenic elements and detritus into the sea with an aim of preservation of of fish resources.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 36–49, January–February, 2009. 相似文献
822.
Specific features of variations in the bottom topography of the mid-ocean rift zones with intermediate spreading rates are considered in this work. The rift zones with a transition morphology are analyzed, and the main features of the transition topography are distinguished. Several successive stages of topographic variations, each of which is characterized by a specific relative position of the topographic features of the rift zone cross section, have been distinguished based on an analysis of the character of rift zone topographic variations in going from axial rises to rift valleys. The specific features of variations in the structural segmentation of rift zones with intermediate spreading rates, depending on the morphological changes, have been established. The thermal models of the structure of the rift zone magmatic formations have been considered, and the geodynamic relations of the magmatic systems with the specific features of the morphology and the structural segmentation of the mid-ocean axial zones with the intermediate spreading rates have been discussed. 相似文献
823.
D. V. Kulyamin E. M. Volodin V. P. Dymnikov 《Izvestiya Atmospheric and Oceanic Physics》2009,45(1):37-54
The problem of simulating quasi-biennial oscillations (QBOs) of zonal velocity in the equatorial stratosphere in atmospheric general circulation models is considered. In accordance with the results from Part I of this study on the basis of the models developed at the Institute of Numerical Mathematics of the Russian Academy of Sciences (INM RAS), the possibility of implementing (in these models) mechanisms of QBO excitation through both the interaction of planetary waves with the mean flow and breaking of short gravity waves is investigated. A new high-resolution 2° × 2.5° × 80 version of the INM RAS model is designed, a climate simulation with the two 2° × 2.5° × 39 and 2° × 2.5° × 80 versions of the INM RAS model is briefly described, results of spectral analysis of equatorial wave activity are presented, and the QBO formation processes in these models are considered in detail. For the new 2° × 2.5° × 80 model, realistic QBOs of zonal wind are obtained as the result of the action of both mechanisms. 相似文献
824.
Pockmarks in the inner Oslofjord,Norway 总被引:2,自引:3,他引:2
Multibeam bathymetric surveys of the Inner Oslofjord, Norway have revealed a high density of pockmarks in the 179-km2 inner fjord area, which contains over 500 pockmarks of varying size, typically 20–50 m in diameter and 2–10 m deep. These
pockmarks have been investigated with a variety of techniques, including acoustic subbottom profiling, sedimentological and
geochemical analyses of cores, remotely operated vehicle observation, and morphometry. Both the distribution and shapes of
the pockmarks suggest that they are related to structures in the bedrock underlying relatively thin (<50 m) unconsolidated
glacial and postglacial sediments. The data provide no direct indication of a particular mode of pockmark formation, but release
of large amounts of biogenic, shallow methane seems unlikely. Several lines of evidence point to a continuous process of pockmark
formation followed by inactivity, with some pockmarks recently active whereas others have been inactive for a considerable
time. Some pockmarks are characterised by coarse sediment in their centres. The density, variety and easy access make this
pockmark field an ideal model area for pockmark research.
John S. Gray is deceased. 相似文献
825.
This paper documents a new method for describing channel-related sedimentary deposits based on formal language theory. Using this method an analogue model of a sedimentary deposit can be encoded as a grammar. A program, called a parser, has been developed which can generate stochastic maps of these sedimentary deposits based on information in a specified grammar. The maps of sedimentary deposits generated by the parser have the same type, spatial arrangement, shape and size distribution as the analogue model. The successful generation of depositional maps represents a crucial step in the ongoing development of a new technique designed to generate 3D static geological models of sedimentary successions. The maps can be conditioned to match sparse hard data in the form of channel segments interpreted from seismic horizon maps. 相似文献
826.
Taro Takahashi Stewart C. Sutherland Rik Wanninkhof Colm Sweeney Richard A. Feely David W. Chipman Burke Hales Gernot Friederich Francisco Chavez Christopher Sabine Andrew Watson Dorothee C.E. Bakker Ute Schuster Nicolas Metzl Hisayuki Yoshikawa-Inoue Masao Ishii Takashi Midorikawa Yukihiro Nojiri Arne Krtzinger Tobias Steinhoff Mario Hoppema Jon Olafsson Thorarinn S. Arnarson Bronte Tilbrook Truls Johannessen Are Olsen Richard Bellerby C.S. Wong Bruno Delille N.R. Bates Hein J.W. de Baar 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(11):2075-2076
827.
E. N. Badyukova 《Oceanology》2010,50(6):953-960
On the basis of geologic-geomorphologic studies, an alternative concept regarding the evolution of the Northern Caspian Sea
Region and the adjacent areas in the boundary of the Pleistocene-Holocene is presented. A supposition is made about the existence
of a large lagoon in the North Caspian Region that the Volga River emptied into forming a delta. Later, water from the lagoon
flowed as a “stratum” stream into the Black Sea through the Manych Strait. A conclusion is reached that the Baer mounds were
formed on the bottom of this stream. 相似文献
828.
The structure of the assemblages associated with the mussel aggregations of Bathymodiolus azoricus was investigated. The mussel beds were found on the hydrothermal vent fields on the Mid-Atlantic Ridge (the Menez Gwen, Lucky
Strike, and Rainbow areas) at the depths of 850–2400 m. The community structure of the mussel bed assemblages varied between
the studied areas. Large number of species was unique to Menez Gwen mussel beds; the most observed taxa were not specialized
hydrothermal species. All the other, nonunique species were found for the Lucky Strike region. The lowest mussel assemblage
structure evenness was observed in the shallowest area, the Menez Gwen area (850 m depth). We assume that two types of mussel
assemblages—nematode-dominated and copepod-dominated ones—exist in the Lucky Strike field. The assemblages of B. azoricus differ significantly from the assemblages of B. thermophilus inhabiting the Pacific hydrothermal vents. 相似文献
829.
Appropriate conditions have been achieved for the accurate, rapid, and highly precise shipboard simultaneous determination of dissolved organic carbon and total dissolved nitrogen in seawater by high temperature catalytic oxidation. A nitrogen-specific Antek 705D chemiluminescence detector and a CO2-specific LiCor Li6252 IRGA have been coupled in-series with a Shimadzu TOC-5000 organic carbon analyser. Precision of both simultaneous measurements is ≤1.5%, i.e. ±1 μmol C l−1 and ±0.3 μmol N l−1, respectively. Quality of analysis is not compromised by vibrations associated with ocean going research vessels. 相似文献
830.
T. Richard Seaborne 《Marine and Petroleum Geology》1996,13(8):963-972
The Shabwa Basin is the northeastern extension of the Marib-Al Jawf-Shabwa system of Mesozoic grabens, located onshore in the Republic of Yemen. An evaporitic sequence with an estimated maximum depositional thickness of 300 metres was deposited during the Tithonian. It is designated the Sabatayn Formation and exerts significant control on most of the play elements in the principal hydrocarbon play systems anticipated in the northeastern part of the basin. Migration of hydrocarbons from pre-salt source rocks into intra-and post-salt reservoirs is restricted by the evaporites. Localised heat flow perturbations introduced by the salt, increase the maturity of post-salt source rocks. Post and intra-salt reservoirs are structured by listric faulting on a salt detachment, salt pillowing due to post-depositional loading, by local salt dissolution and by late folding due to gravity sliding of the post-salt section on a salt detachment. Early dissolution and reprecipitation of salt is responsible for occlusion of porosity in intra-salt clastic reservoirs. 相似文献