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1.
A second paper devoted to problems of predicting the future level of the Caspian Sea attempts, as did the first, to discount overly simplistic explanations for its nearly century-long decline and recent slight rise. Long-term climatic changes within the drainage basin of the Caspian and the resultant change in discharge of tributary rivers are proposed as the basic mechanism controlling sea level fluctuations and not, as argued in the popular press, tectonic movements, groundwater discharge variations, or the damming of the Kara-Bogaz-Gol. Various models for predicting future levels are compared, although no specific forecasts are made (translated by Andrew R. Bond).  相似文献   

2.
The first of two papers on the problem of forecasting the level of the Caspian Sea evaluates factors widely believed to have been responsible for its lowering during much of the present century (including tectonic movements, climatic cycles, human activity). It concludes that previous forecasts have been inaccurate because of the failure to adequately model the complexity of processes involved, specifically the internal mechanisms of “self-regulation” of water levels. Continuation of the recent slight rise in the Caspian's level is predicted at least into the early 1990s (translated by Andrew R. Bond).  相似文献   

3.
The author raise several significant problems involved in plans to establish resort functions on the Apsheron Peninsula, which together with its major metropolitan areas (Baku and Sumgait), serves as a center for oil refining and petrochemical production based on significant offshore oil drilling in the Caspian Sea. Among these problems are the fact that part of the area of greatest resort/recreational potential (northern coast) is also the area of highest SC2 concentrations (reflecting chemical production in Sumgait), and that another promising location (southern coast) exhibits high levels of NO2 (largely attributed to automobile traffic and power generation in Baku) (translated by Andrew R. Bond).  相似文献   

4.
The delta of the Volga River on the Caspian Sea is a highly dynamic form, whose growth has been affected by a combination of physical and human factors. Rapid delta growth in recent years has resulted in a deterioration of both physical and economic conditions (navigation problems, inadequate moisture supply, overgrowing of shallows with vegetation, loss of spawning grounds). Regression analysis yields a number of relationships between the inflow of water and suspended sediments, on the one hand, and delta growth, on the other hand, with a distinction between periods of a lowering of the Caspian Sea level and relative stability. The regression equations are used to project the likely future evolution of the delta. The only combination of conditions that is likely to limit further delta growth by the year 2000 is the stability of the Caspian Sea level and a period of average moisture supply. In all other cases, the delta is likely to continue its undesirable advance.  相似文献   

5.
In an effort to stabilize the declining level of the Caspian Sea, it has been proposed that evaporation from the water surface be reduced by decreasing the size of the sea through construction of a dam in the northern portion. Data on the geology and hydrology of the Caspian Sea bed suggest that the construction of a dam might have undesirable consequences not only for the northern fisheries basin but for the sea as a whole. The findings are based on the presence of salt domes on the bottom of the northern Caspian Sea. An influx of highly mineralized subsurface waters along faults associated with the salt domes as well as leaching of salt from the structures themselves may threaten to raise the salinity of the northern fisheries basin to intolerable magnitudes. The presence of a man-made dam, in the author's view, would also interfere with the natural circulation of water, threatening contamination of deeper layers of the Caspian Sea with hydrogen sulfide, as has happened in the case of the Black Sea. [For a discussion of the Caspian Sea problem, see Soviet Geography, November 1972.]  相似文献   

6.
Although both the Caspian and Aral Sea basins are affected by fluctuations in the general moisture conditions affecting the Northern Hemisphere, the two drainage basins react differently to identical moisture changes both over the long term and over the short term. Over the short term, a shift in wet periods has been observed between the European part of the USSR, which contains the Volga basin draining into the Caspian, and western Asia, which contains the Aral Sea drainage basin. Since there is a direct relationship between general moisture conditions and level changes, the short-term level fluctuations would be heterochronous (out of phase) in the two seas. Over the long term, the comparison is complicated by the fact that Caspian drainage derives mainly from snow meltwater in the Russian plain while Aral Sea drainage derives from a combination of snow and glacier meltwater. Glacier runoff tends to increase in dry, warm periods and to decrease in wet, cold periods of glacier growth, while snow is related directly to general moisture conditions.  相似文献   

7.
A number of investigators have noted a movement of Soviet population toward the seacoasts, contrasting with the nation's traditional inland development. The pull of the coast has been linked to the increasing foreign trade of the USSR and to greater involvement in ocean affairs in general. The author analyzes the recent growth of maritime urban places in terms of the nation's major maritime regions: Azov-Black Sea, Baltic, Caspian, Pacific and Arctic, compares the rates of urban population growth and discusses some of the factors that account for differences in regional development.  相似文献   

8.
A specialist in loess geomorphology and arid-zone hydrology distinguishes three categories of factors accounting for waterlevel changes in the Aral Sea. She judges the most significant to be changes in inflow resulting from changes in the course of the Amudarya, the more important of the two tributary streams. The Amudarya at various times emptied into the Sarykamysh depression, southwest of the Aral Sea, giving rise to a flow of water through the now dry Uzboy channel to the Caspian Sea. Climatic change, involving alternations of wet and dry cycles, is said to have accounted for only minor water level fluctuations, of the order of 4 to 6 m, against the background of the major fluctuations produced by the Amudarya course migrations. Human activity, notably irrigation, is regarded as having become significant only in modern times as a result of an expansion of irrigation works. The present abrupt decline in the Aral waterlevel (6 m from 1960 to 1977, including 2 m in the last three years) is attributed to the combination of a dry climatic cycle and greatly increased use of water for irrigation.  相似文献   

9.
On the basis of new calculations of the loss of water through evaporation from the temporarily flooded litteral zone of the northeast Caspian and the possible savings in the water budget that might be achieved by partitioning off the northeast shoals, the authors conclude that little would be gained by any project designed to reduce the water area of the northern Caspian.  相似文献   

10.
Differences in available data on the area of the Caspian Sea are analyzed, and an effort is made to explain them. The differences are particularly pronounced in the shallower northern portion of the sea, where the drop of the sea level over the years has produced more significant changes in shoreline configuration. Greater use of space imagery is urged in determining changes in shoreline configuration, and the setting of “geographical standards” is proposed to avoid continuing confusion in published data. The technical problem of calculating the physical water area, including surface roughness produced by wave motion, is discussed.  相似文献   

11.
The Transformation of the Caspian Sea   总被引:1,自引:0,他引:1  
The author reviews the problem of the level fluctuations of the Caspian Sea, particularly the steady drop since 1929. The drop in level is affecting many key sectors of the regional economy. Among several remedial schemes is a plan for diverting the rivers of northern European Russia to the Caspian, and a project for a localized regulation of the level of the Caspian Sea.  相似文献   

12.
The author analyzes a functional relationship between the historical fate of the Khazar people of the Caspian steppe and changes in the landscape produced by an alternation of wet and dry cycles and changes of the Caspian Sea level. A previous article of this series appeared in Soviet Geography, June 1964.  相似文献   

13.
The increasing demand on water in the Soviet Union and the problem of assuring water quality require the construction of long-term water-management balances by drainage basins. These balances, based on predicted demand and water availability, would suggest the need for water-management projects within basins and interbasin transfers. Water needs would be evaluated both in terms of water requirements by categories of users and in terms of water quality. The most crucial regional problems involve the increasing shortage of water in Central Asia (with the prospect of interbasin transfer from Siberia) and in southern regions of the European USSR (with the problem of diverting water southward from the northern runoff slope). The Caspian Sea is expected to require a supplementary inflow of 80 to 100 cubic kilometers a year by the end of the century if the decline of its waterlevel is to be arrested. But southward diversion of northern waters is not expected to add more than 50 to 70 km3 at best, with a possible saving of an additional 10 to 20 km3 through decline of evaporation from a reduced Caspian Sea surface. The preservation of conditions in the Sea of Azov, the Aral Sea and Lake Balkhash pose additional water problems. [The senior author died in October, 1974].  相似文献   

14.
The author tries to show that the level of the Caspian Sea could be stabilized at relatively low cost at its present low level without further damage to the coastal economy. He denies the need for costly projects designed to increase the inflow into the Caspian or to separate the shallow northern section from the main body of the sea. He maintains that water gained by diverting the northern streams into the Volga basin should be used to irrigate the arid Southeast rather than to replenish the water supply of the Caspian Sea.  相似文献   

15.
Abstract

The authors review expected water requirements within the Volga-Caspian basin for industry, agriculture, fisheries and municipal uses and plans for the diversion of the streams of northern European Russia to the south to support the level of the Caspian Sea. They suggest that the diversion of part of the flow of the northern streams and isolation of the natural evaporation basin of the Kara-Bogaz-Gol will be sufficient to maintain the Caspian Sea level at ?28 meters. Previous articles on the Caspian problem appeared in Soviet Geography, September 1961, January 1962, and June 1963.  相似文献   

16.
An early 1949 version of Davydov's grandiose scheme for diverting water from the Yenisey and Ob' Rivers to Kazakhstan and Central Asia via the Turgay Gates and the Aral and Caspian Seas in order to stabilize the level of the Caspian, expand the irrigated acreage of Kazakhstan and Central Asia, generate abundant hydro-electric power, provide a cheap water transport route between Siberia and Central Asia, eliminate sukhovei (dry winds) at their source, and ameliorate the continental climate of Western Siberia, Kazakhstan, and Central Asia. The plan reflects the anthropocentric “transformation of nature” and the large-scale “great projects of communism” drives of the late Stalinist period. The translation was prepared by James R. Gibson of York University, Toronto.  相似文献   

17.
Abstract

Reconstructions of the late Quaternary paleogeography of Greece and the Aegean show that at 18,000 years B.P. the northern Aegean and northern Adriatic formed large coastal plains traversed by many rivers. Broad plains also existed off the coast of Elis and the present Gulf of Korinth, and along the Anatolian coast. Many islands, such as Kerkira, Euboea, and the northern Sporadhes, were connected with the mainland, and most of the Cycladic islands were joined together in a Cycladic semi-peninsula. The post-glacial rise of sea level beginning ca. 15,000 B.P. restored around 9,000 B.P. the coastal geography to approximately its present configuration. The late Quaternary paleogeography and its subsequent changes have many archeological implications that are worth serious consideration. The well-watered northern coastal plains may have furnished subsistence for a plains population quite independent of the resources of the northern mountain regions, and they constituted easy access to the Greek peninsula from the NE and NW. Loss of coastal plain land during the post-glacial rise of sea level drastically changed the resource base in many areas. The island of Melos, known source of obsidian for toolmaking since at least 10,000 B.P., may have been discovered considerably earlier when access to the island was largely over land.  相似文献   

18.
ABSTRACT This study estimates the impact of sea‐level rise on coastal real estate in North Carolina using a unique integration of geospatial and hedonic property data. With rates of sea‐level rise approximately double the global average, North Carolina has one of the most vulnerable coastlines in the United States. A range of modest sea‐level rise scenarios based on the IPCC Fourth Assessment Report projections (2007) are considered for four counties of North Carolina—New Hanover, Dare, Carteret, and Bertie—which represent a cross‐section of the state's coastline in geographical distribution and economic development. High‐resolution topographic LIDAR (light detection and ranging) data are used to provide accurate inundation maps for the properties that will be at risk under six different sea‐level rise scenarios. A simulation approach based on spatial hedonic models is used to provide consistent estimates of the property value losses. Considering just four coastal counties in North Carolina, the value of residential property loss without discounting in 2030 (2080) is estimated to be about $179 ($526) million for the mid‐range sea‐level rise scenarios. Low‐lying and heavily developed areas in the northern coastline are comparatively more vulnerable to the effect of sea‐level rise than the other areas.  相似文献   

19.
Palaeogeographic analysis and radiocarbon dating indicate that sometime in the second half of the fifth millennium BC a sea-level rise occurred along the coast of the western side of the Arabian (Persian) Gulf. Cultural remains of the'Ubaid archaeological period are intimately associated with the event and the palaeogeographic environment that accompanied it. The sea-level rise appears to have had a catastrophic effect on habitation sites.  相似文献   

20.
Previous and current fieldwork has generated a significant body of data on the occupation of the south coast of Peru during the Formative Period (ca. 3800-2200 B.P.). These data are placed in a synthetic framework and evaluated and compared to the trajectory of cultural development in the better studied regions of the Central Andes. Critical review of this panorama necessitates consideration of the relative chronological framework and definition of the Formative Period, the parameters and validity of the south coast as a culture area, contacts south coast societies sustained with other Central Andean regions, and the role of monumental architecture in the rise of complex society.  相似文献   

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