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1.
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   

2.
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   

3.
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   

4.
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   

5.
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   

6.
In view of the declining inflow into the Aral Sea, alternative proposals are advanced to save this inland sea by reducing its area as well as its salinity levels. The proposals involve the closing off of some portions of the sea, notably the Little Aral in the northeast and the Western Aral, from the large shallow eastern portion. Some portions of this fragmented sea would then be treated as active bodies of water with a throughflow regime, discharging surplus waters of high salinity into other portions, which would be allowed to become salt marshes. Various combinations of active water areas and residual water areas are examined, and possible trends in waterlevel and salinity are projected to the middle of the 21st century.  相似文献   

7.
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   

8.
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   

9.
The authors, questioning the implications for the Caspian of a conventional model of shoreline dynamics on a flat, sandy coast upon a rise in sea level, present the findings of field observations made along the Dagestan shore during the period (post-1977) of the recent rise of the Caspian Sea level. They argue that changes in coastal morphology have varied largely according to the steepness of the offshore slope and, in general, sharply accelerated erosion was observed only on more steeply sloping sections of coast and in areas previously protected by rock benches (translated by Jay K. Mitchell; PlanEcon, Inc.; Washington, DC 20005).  相似文献   

10.
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   

11.
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   

12.
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   

13.
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   

14.
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   

15.
哈大巨型城市带要素集聚分异与空间极化格局   总被引:3,自引:0,他引:3  
在界定空间极化概念的基础上,应用均匀度指数、基尼系数、崔王指数分析城市带内部要素集聚程度分异及空间极化格局,结论如下:①1990-2014 年哈大巨型城市带要素集聚程度时空分异明显,"核心-边缘"结构逐步显现,城市带内部基于要素集聚程度的哈长与辽中南次区域逐渐发育;②城市带内部要素集聚存在显著的空间极化,空间极化的"四城市"格局已经形成;③城市发展内源力是哈大巨型城市带整体空间极化的主要影响因素,城市投资强度和经济发展水平对城市带空间极化格局演变的影响也较显著。城市投资强度与吸引力差异是哈长次区域空间极化分异的重要影响因素,而城市发展内源力是影响辽中南次区域空间极化的主要因素。  相似文献   

16.
The long-term grain requirements of the growing Soviet population are calculated. On the basis of the relationship between water use and grain yields by natural soil zones of the USSR, the authors show that the amount of water needed per unit of output declines with a growth of productivity, especially in the non-chernozem zone of the Soviet Union. It is therefore concluded that greater water savings might be assured by expanding grain production in zones with an adequate supply of natural moisture rather than by the use of artificial irrigation of arid lands.  相似文献   

17.
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   

18.
The Sarykamysh depression of Soviet Central Asia, southwest of the Aral Sea, has begun to fill with water since around 1960 after having lain dry for 350 years. As of 1976, the lake, fed mainly by irrigation drainage water from the nearby Khorezm (Khiva) oasis, had grown to 2,000 km2, with a depth of at least 40 m. The depression was receiving 4 to 4.5 km3 of water a year and continued to fill. While the appearance of such a large body of water in the desert would appear in itself to be a positive development, the question is raised whether the water would not be put to better use by being directed toward the Aral Sea.  相似文献   

19.
关伟  王春明 《人文地理》2014,29(3):103-108
沈阳经济区作为国家新型工业化综合配套改革试验区,对其区域差异的研究具有重要的意义。通过研究区域自1992年以来经济重心的动态演化过程,得出该地区经济发展县际差异的动态变化规律,并且就其演化的机制因子进行了分析。研究表明:沈阳经济区经济重心主要介于沈阳市苏家屯区和辽阳市灯塔县之间,基本接近几何中心,并与几何中心的距离呈现不断缩小的趋势,表明区域经济发展的不平衡性在减弱。19年来,经济重心总的移动趋势为先由东北向西南移动,再由西南向东北推进,但移动轨迹呈现出一定的曲折和波动,其年移动距离和方向与区域经济发展水平、速度及政策等显现正相关关系,反映出区域不同时期发展战略政策的变化。  相似文献   

20.
李军  李恩玮 《考古学报》2008,(2):253-272,图版伍-图版贰拾
普彤塔位于邢台南宫市西北1.5公里,旧城村东北约200米处,原普彤寺内(图一)。1966年3月8日,邢台大地震时从普彤塔上震落观音铜造像3尊(NW006、NW040、NW047)。1990年10月,河北省文物局拨款对四层以上普彤塔进行落架重修时在塔身佛龛内又发现铜造像39尊。  相似文献   

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