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631.
We study the processes of global self-regulation of Earth’s biota (GAIA-theory) by applying the method of adaptive balance of causes proposed by the authors. By using, as an example, the Daisy World model constructed by this method, we reveal the phenomenon of preservation of the mean temperature of Earth’s surface due
to the presence of the vegetation cover. We develop an integral model of global natural, social, and economic processes in
which the World Ocean is one of the factors regulating the amount of greenhouse gases in the atmosphere. The decrease in the
amount of greenhouse gases in the atmosphere caused by the GAIA-effects increases the number of hurricanes and floods on the Earth. As a result, the levels of ecological and social hazards
for the mankind become much higher. To eliminate these threats, it is necessary to intensify the processes of self-organization
of the society realized via the improvement of education, development of science, and global regulation of the competition
for natural resources. We present the results of numerical experiments performed by using the model demonstrating possible
scenarios of global development with regard for the processes of self-organization of the society.
__________
Translated From Morskoi Gidrofizicheskii Zhurnal, No. 3, Pp. 62–80, May–June, 2007. 相似文献
632.
Akcha F Tanguy A Leday G Pelluhet L Budzinski H Chiffoleau JF 《Marine environmental research》2004,58(2-5):753-756
DNA single-strand breaks were measured by the comet assay in both gill and hemolymph cells of mussels collected in 3 sampling areas of the French coast (Pointe du Castelli, Pen Bron and Saint-Nazaire Harbour). Whole mussel tissue samples were also collected for the chemical determination of PAH, PCB and heavy metal concentrations. In mussel, a higher level of DNA strand breaks was measured in gill than in hemolymph cells (p < 0.01). Despite a factor of contamination from 2 to 3 between sites, no difference in the extent of mussel DNA strand breaks was shown between sampling locations (p > 0.05), questioning the sensitivity of the assays used in biomonitoring studies. 相似文献
633.
Periods and amplitudes of long-term temperature fluctuations were obtained using the methods of spectral analysis and filtration of secular time series of the air temperature at 13 hydrometeorological stations in the Black Sea region. The prognostic calculations of the long-term air temperature variability are based on the results of processing of time series. The calculations of the air temperature agree with the data of observations. The possibility of the long-term air temperature variability prediction is shown. 相似文献
634.
Petroleum hydrocarbons were investigated in Mytilus edulis and Macoma balthica at six intertidal sites in Port Valdez, Alaska after three to five years of oil terminal operation. Information about the concentrations of total hydrocarbons, unresolved complex mixture, normal alkanes, isoprenoids, olefins, hopanes and polycyclic aromatic hyrocarbons shows that petroleum accumulation in these bivalve mollusks is greatest at the Valdez municipal boat harbor and a crude oil terminal which has been permitted to discharge 170 kg oil day−1. Accumulation two- to ten-fold less were observed at 3 km from the terminal and boat harbor. The temporal trends in petroleum hydrocarbon concentrations in M. edulis and M. balthica reflect the effects of selective retention and depuration of different hydrocarbon classes as well as variation in hydrocarbon sources. It is not clear whether the petroleum concentrations in Port Valdez bivalves had reached steady state by 1982, the final sampling time reported here. 相似文献
635.
636.
In application to the Crimean regional centre for satellite data reception, treatment, and dissemination, we have identified
the earth’s satellite-surveyed areas, with orbital heights (H) ranging from 650 to 750 km. This paper shows that for the Ukrainian territory and the Sea of Azov-Black Sea environment
to be monitored, the regional centre’s receiving station must be capable of receiving radar signals from a range of about
1500 km. For typical high-speed radio lines, this may be achieved through the use of a satellite data-receiving station, with
the antenna’s diameter being about 3 m.
Translated by Vladimir A. Puchkin. 相似文献
637.
cDNA's coding for cytochrome P4501A1 (CYP1A1), phenol UDP-glucuronosyltransferase (UDPGT) and glutathione S-transferase (GST-A) were cloned and sequenced from an expression library prepared from the liver of a 3-methylcholanthrene (3-MC) induced plaice. Plaice CYP1A1 and Phenol UDPGT display a high degree of structural conservation with homologous mammalian isoforms and their mRNAs were shown to be highly induced in liver after 3-MC treatment of fish. Expression of plaice GST-A, which displays closer homology to GSTs from plants and invertebrates than those of mammals, is repressed after 3-MC treatment. 相似文献
638.
Arthur C. R. Gleason Diego Lirman Dana Williams Nuno R. Gracias Brooke E. Gintert Hossein Madjidi R. Pamela Reid G. Chris Boynton Shahriar Negahdaripour Margaret Miller & Philip Kramer 《Marine Ecology》2007,28(2):254-258
Four hurricanes impacted the reefs of Florida in 2005. In this study, we evaluate the combined impacts of hurricanes Dennis, Katrina, Rita, and Wilma on a population of Acropora palmata using a newly developed video‐mosaic methodology that provides a high‐resolution, spatially accurate landscape view of the reef benthos. Storm damage to A. palmata was surprisingly limited; only 2 out of 19 colonies were removed from the study plot at Molasses Reef. The net tissue losses for those colonies that remained were only 10% and mean diameter of colonies decreased slightly from 88.4 to 79.6 cm. In contrast, the damage to the reef framework was more severe, and a large section (6 m in diameter) was dislodged, overturned, and transported to the bottom of the reef spur. The data presented here show that two‐dimensional video‐mosaic technology is well‐suited to assess the impacts of physical disturbance on coral reefs and can be used to complement existing survey methodologies. 相似文献
639.
The currents and surface level oscillations in the Sea of Azov ensuing from contraction of the mouth of Taganrog Bay are computed using the grid technique on the basis of a numerical solution to the system of quasi-linear, degenerate, parabolic, partial derivative equations (shallow-water equations). It is demonstrated what changes are to be expected in the dynamics of the Sea of Azov should this project be realized. The computations were carried out for typical wind directions.Translated by Vladimir A. Puchkin. 相似文献
640.