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    15 July 1994, Volume 49 Issue 4 Previous Issue    Next Issue
    NEW RECOGNITIONS OF QUATERNARY ENVIRONMENT IN THE NORTHWEST TIBETAN PLATEAU
    Zhang Qingsong, Li Bingyuan, Zhu Liping
    1994, 49 (4):  289-297.  doi: 10.11821/xb199404001
    Abstract ( )   PDF (593KB) ( )   Save
    Various new data derived from the investigations to the West Kunlun shan and Karakorum Shan area in the duration from 1987 to 1992 testify again that the intense uplift of west Tibetan Plateau began from the end of Pliocene to early Pleistocene (e. g. about 3.4 Ma) . A total amplitude of the uplift since that time is 3 100-3 600m which is similar to the Himalayas. The uplift is characterized by totality and stadiality and being accelerated in the late period. Present mean uplift rate along the high way from Yecheng to Shiquanhe is 4. 2 mm/a.according to the repeated measurement carried out in 1959-1961 and 1979-1981. It means that the North-western Tibetan Plateau is still in the intense uplift period at present day.Due to the intense uplifting, climate over the Northwestern Tibetan Plateau has been changed significantly which has exerted great impact on the development of glaciation, loess deposition. interior lakes and drainage system etc.Three glaciations can be recognized in the area. The earliest one appeared in early-middle Pleistocene and the later two occurred in the late middle Pleistocene and late Pleistocene respectively. The glaciation of the early Pleistocene which was referred by former investigators had never appeared in this area. The middle Pleistocene glaciers were well developed as a maritime monsoon glacier type in forms of piedmont glaciers or trellis valley glaciers. Glaciers in the later stages were changed to be continental style in forms of tongue, cirque and valley glaciers.They were consequently decreased in size since the late Pleistocene. It was impossible to develop an ice sheet on the Plateau during the last glaciation. This indicates that climatically it became colder and drier in the area in the late Pleistocene and Holocene stages followed by intense uplift.Loess deposits are scare to the south of the Kunlun Shan . but well developed and widely distributed on the northern side of the West Kunlun Shan with maximum thickness of 20m below an elevation of 4 200m asl. The loess began to deposit after 158kaBP. and accumulate more intensively in the Holocene. Evidences show that the loess on the northern slope of West Kunlun Shan is a correlative deposits of the sand dunes on the southern periphery of the TarimBasin under the environmental disintegration in the late Pleistocene and Holocene ages. The desertification in the Tarim Basin therefore might mainly be generated from the late Pleistocene time.Evidences show that there were many big ancient lakes which were combined with the existing isolated lakes in the Karakorum-West Kunlun Shan area during 40-20kaBP since about 20-18kaBP. most of them were separated into small isolated lakes because lake level was significantly dropped down. During the Holocene. processes of lake shrink became fast after the isolated lakes settled. For instances. the level of the Longimu Co has dropped down by more than 72m since about 11 kaBP. The intense lake shrinkage appeared in recent 20ka might be contributed to the continued uplift of the Plateau in late Pleistocene except the global changes. 
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    RESEARCH ON THE FORMATION AND LATERIZATION OF THE “OLD RED SANDY SEDIMENT”ALONG THE COAST OF SOUTH CHINA
    Wu Zheng, Huang Shan, Jin Zhimin, Hu Shouzhen
    1994, 49 (4):  298-306.  doi: 10.11821/xb199404002
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    One kind of semicement medium-fine sand sediment with red (10 R 4/8) of brown-red (2. 5YR 4/8) colour which is known as "Old Red Sandy Sediment". is intermittently distributed southwards along the coast of South China from the Pingtan island in Fujian Province. By investigating in field along the coast of South China and experimental analysing in laboratory, the authers confirm that the "old Red Sandy Sediment" is belong to the coastal aeolian deposit formed in the last glacial period of late Pleistocene according to its distribution. landform, deposition and age, which was considered as the proximal littoral deposit in the past. The experimental research also shows that the red colour of the seiment is contributed to a film of red clay material coating on the suface of uncoloured quartz sands. which is composed of clay minerals mainly as kaolinite, mixing with ferric oxides such as hematite and geothite. The clay minerals were formed by weathering of the minerals as feldspar in the paleo-aeolian sands under the condition of a wet and hot climate in the high-temperature period of sub-interglacial or postglacial stage, and the ferric oxides are derived from oxidization ferric-silicate minerals.Development of the "Old Red Sandy Sediment" went through about two different stages which were coastal aeolian deposition stage in the period of the sub-glacial──the lower sea level andweathering (oxidization) stage in the sub-interglacial or postglacial high-temperature period the higher sea level. The former is the original formation process of coastal aeolian deposition and the latter is the intense subsequent oxidization (laterization) process. The time of laterization is no more than 104 years. 
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    A STUDY ON THE OASIS ECONOMIC AND ECOLOGICAL SYSTEM BY USING THE METHOD OF SYSTEM DYNAMICS──TAKING THE MANAS OASIS AS AN EXAMPLE
    Han Delin, Chen Zhengjiang
    1994, 49 (4):  307-316.  doi: 10.11821/xb199404003
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    This research is intended to examine the internal cause of the development of oasis economyecology system, as well as the interaction between oasis and its environments in arid area by using the current theories, viewpoints and methods of system science, to explore a method to assess the loading capacity of oasis’ ecological system, to enlighten the relations between the evolutions of oasis and human behavior on society and economy. to test and choose a best way to control an oasis system by means of a Dynamic model of oasis sytem.Thearticle consists of four parts:1 The economy-ecology system of oasis and its basic feedback structure The genearal concept of oasis and oasis economy-ecology system is presented first, then its characters as well as feedback structure are analysed.2 The practice to establish a Dynamic model of oasis In this part, the problem is to establish a Dynamic model of oasis system.3 The main situation of the development of the economy-ecology system and the relations between it and main policies in the Manas oasis.In this part, some problems about the oasis development, such as the population and economy growth. Alloting invests. planting structure, water resources, optimal accumulation are studied by Model simulating.4 The loading capacity of land resources in the Manas Oasis In this part, the loading capacity of land resources in the Manas Oasis is roughly estimated by its possible living productions that are presented by the model simulating results. It is about 1-0.1. 2 and 1. 4 millions people in 2000. 2010 and 2020 respectively. 
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    DYNAMICS OF GROUND SUBSIDENCE AND ITS EFFECTS ON GEOGEAPHICAL ENVIRONMENT IN THE TIANJIN AREA
    Wang Ruobai, Sun Dongping, Geng Shichang, Hang Yueping
    1994, 49 (4):  317-323.  doi: 10.11821/xb199404004
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    Based on the data of precise repeated leveling from 60’s to the late 80’s and by using the uniform adjustment calculating method, the uniform initial points and the same network. the maps of crustal vertical deformation rate (1965 to 1975, 1975 to 1979, 1979 to 1983, 1983 to 1988) have been produced in Tianjin and its adjacent areas. Combing with the geological and seismological background, the features of ground subsidence and the dynamic of its development in this area have been studied.The results obtained show that the main reasons for ground subsidence and for increase of coastal disasters are overpumping of underground water, especially in the tectonic sinking areas like TianJin and its adjacent areas. The funnels of ground subsidence distributed in TianJin and its adjacent areas have been developed to a very critical extent, and a series of secondary disasters associated with ground subsidence should take place in the near future. such as sea inundation and flooding with strom surges. the siltation of river channels and flooding involved. deterioration of hydrogeological canditions etc. 
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    A STUDY ON THE MATHEMATICAL MODEL OF RIVER-BED DYNAMICS WHICH INVOLVES NEOTECTONIC MOVEMENT
    Jia Shaofeng
    1994, 49 (4):  324-331.  doi: 10.11821/xb199404005
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    Firstly, for the purpose of studying the integrated effects of many factors on river-bed profile.we considered to put neotectonic movement into the river-bed dynamics model. We got a mathematical model of river-bed dynamics which includes neotectonic movement.Then we studied the effects of different neotectonic movements on river-bed profile and sediment transportation. Some quantitative relations and expressions are studied and gived. For example. the relation between a small quantity of tectonic movement δT and the thickness of deposits δZs. induced by δT’ is that δZs. equals to T. but the signs are differandt Because the change of river-bed profile δZb = δZs +δT= (-δT) +δT=0. δT has no effect on river-bed profile.At last, we distinguished the neotectonic movement at the Lower Yellow River. The neotectonic falling is about 5 mm/a at the Lower Yellow River. Acording to the analysis above. it is clear that the neotectonic movement has no obvious effects on the river-bed profile at the Lower Yellow River, but it has obvious effects on the sediment transportation. There must be an equal quantity of deposits to compensate the neotectonic falling as great as 5mm/a. 
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    RECONSTRUCTION OF ANNUAL WINTER MEAN TEMPERATURE SERIES IN HEFEI AREA DURING 1736-1991 A. D.
    Zhou Qingbo, Zhang peiyuan, Wang zheng
    1994, 49 (4):  332-337.  doi: 10.11821/xb199404006
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    In this paper, we used a new and important historical document, which kept in the National First Historical Archive at the Palace Museum. This is a very systematic and rich climatic proxy document, which mainly records the depth of rainfall-penetration and snowfall. the beginning date and ending date of every rainfall or snowfall process in various areas. We find a good correlationship between annual winter mean temperature (T) and snowfall-days (D) in the Hefei area at the measurmental period, and the regression equation is:T=5. 06-0. 173D.According to the equation just mentioned above, an annual winter mean temperature series was reconstructed based on the snowfall-days during the period from 1736 A. D. to 1911 A.D..Since 1911 A. D. the annual winter mean temperature series in Hefei was supplemented by that in Nanjing and the measurmental value in Hefei. Therefore. a complete annual winter mean temperature series for Hefei region was reconstructed from 1736 A. D. to 1991 A. D..By adopting F statistical test, the reconstructed series of annual winter mean temperature is reliable and consistent. Further analysis indicates that there are three warm periods and two cold periods during the last 250 years in the Hefei area by using optimum division method. The warm periods are 1736-1790 A. D. 1851-1871 A. D. and 1907-1991 A. D. . and the coldperiods are.1791-1850 A. D.. and 1872-1906 A. D. . Comparson of temperature changes in different area in China shows that warm period is in 18th and 20th century. and 19th centuryis a cold period. The cold period of 19th century is the last cold period of modern little ice age.In addition. by analysing the temperature changes in the last 250 years in the Hefei area. the middle of 19th century (nearly 1851-1871 A. D.) is a very obvious warm period, and it can not be found in most areas in China. 
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    A PRELIMINARY STUDY ON THE COORDINATION BETWEEN REGIONAL WATER RESOURCES AND ITS NEW CITIES’SETTING UP IN CHINA
    Mou Haisheng, Liu Changming
    1994, 49 (4):  338-344.  doi: 10.11821/xb199404007
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    China has a water balance between water supply and water consumption according to whole country. but there are serious water shortages in some areas, especially in urban areas in the northern China. In general, the cities in the northern China are short of water resource and have less treated waste water. and the cities in southern China are rich in water resource but have water pollution. The paper indicated that the reasons of China’s crisis in water resources in urban areas are undeveloped industrial techniques. large population in the cities and natural conditions. But the irrational distributions and the scales of the cities are the most important causes. For example, there are about 200 cities in the arid. semi-arid. sub-humid areas of China on the north side of Yellow river,which amounts to 47% of total number of the cities in China. But the water resource in this area is only 17. 4 percent of the country’s total water resource. So the water shortage in the North China is mainly caused by natural conditions.Under the rapid social-economic development in recent years. China has a quick urbanization now. More and more towns want to became new cities. In the past decades. the population. socioeconomy. and urban construction were considered when a town was discussed for becoming a new city. The above factors indicate only urban space scale and socio-economical abilities. But whether a new city can develop successfully is determined by its natural conditions and its location. According to the past experience. water resources and water pollution are limiting factors of the cities’ development. So the water resource of the new urban area and where it can be used are very important.In order to avoid the water problems of the new cities, it is necessary for decisionmaking departments of the Government to control the population scales and the developments of the cities by setting up a criteria of water resources supply ability.Then the authors proposed some new issues that should be studied which are presented as following1 The smalles amount (water resource index) of water resources should be taken into account for new cities’ establishment in different regions and for different types. As a whole country. how to plan the cities in China according to the difference among river basins is an urgent research work to be finished. This work is to study the bearing capacity of each river basin’s water resource without water transfer from other river basins. and the largest possible scale of the new cities. The aims of this study are to get the coordinate relationship between river basins’ water resources and its cities, to reduce the limitation of water resources to cities’ development.2 There are many kinds of cities in China according to their functions. They can be divided into industrial and mining, traffic center, tourism, harbor, trade center and multiple-functions cities.The different kinds of cities have different water consumption because of their different industrial structure and inhabitants’ customs. Now the large cities have a lower water consumption per ten thousand RMB of output value because of their advanced techniques. The cities located along large rivers have a higher domestic water consumption. So when we drawn up the water resource indexes for new cities. the characteristics of the new cities should be considered and the different criteria should be given out.3 China has a large territory and a complex natural environment. The available water resources in different regions are different. The theory and methods for water resource assessment are different for different areas. And in the past years. the water conservancy departments emphasized on water quantity assessment. but the environmental protection departments paid much attention on water quality assessment. There is no a united water resource assessment that assesses both water quantity and water quality. The time and spatial distribution and changing law of water resource were rarely considered. So a satisfied assessment of water resource is a united 
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    THE CHANGE IN SOIL PROPERTIES UNDER BEEFWOOD SHELTER BELT ON THE AEOLIAN SANDY COAST IN FUJIAN AND ITS INFLUENCE ON THE REFORESTATION OF THE SLASHLAND
    Zheng Daxian,Sa Jiqin
    1994, 49 (4):  338-344.  doi: 10.11821/xb199404008
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    Beefwood (Casuarina equisetifolia) is the tree of the first importance for windbreak. sand fixation and ecological improvement on the aeolian sandy coast of Fujian. But the reforested beefwood on the slashland do not grow well and are not healthy.The study on the causes of this problem and on the countermeasures are urgently needed for safeguarding the ecological environment. The authors studied the biogeochemical characters of N, P, K, Na. Ca, Mg, Cu, Zn. Fe, Mn, B. Mo. in the beefwood shelter belt on the coast land on the Haitan Island. Fujian. It was found that the trace element Mo in the soils under beefwood forest will be exhausted with the growing of the trees becouse of the unbalanced cycle of the element. Moreover the PH values of the soils will decline, which will further reduce the availability of Mo in the soils. The Mo-exhaustion and acidization of the soils result in a decrease in the content of Mo in beefwood and leads to the unsatisfactory growth of the succeeded beefwood on the beefwood-slashland on sandy coast land in Fujian. According to above results.the authors put forward some countermeasures to preserve and promote the beefwood shelter belt and the ecological environment on the coast in Fujian. 
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    A STUDY ON THE CONTENTS AND SPECIES OF RARE EARTH ELEMENTS IN THE WATER BODY IN THE WUHAN SECTION OF THE CHANGJIANG RIVER
    Wang Lijun,Li Xiuxia,Zhang Shen,Zhang Chaosheng
    1994, 49 (4):  345-352.  doi: 10.11821/xb199404009
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    The contents and partitioning characteristics of rare earth elements (REE) in Wuhan section of the Changjiang River were analysed by neutron activiation analysis (NAA). The contents of solvable fraction of REE in the river was very limited,with the same results as other rivers. On the other hand.the contents of suspended fraction of REE in the river varied in a wide range. It varied with the variation of contents of suspended matter in the water.Contents of REE in the sediments were almost the same with those in the suspended matter. REE were accumulated in fine grained particles,and this showed strong relationship with minerals.The distribution modes showed strong accumulation in the light REE and relatively deficit in Eu. The partitioning charateristics of REE in the sediments and suspended matter were quite similar,With the main amount in residual forms. The amount of five forms obeyed the following order:residual> > bound to organic matter>bound to FeMn oxides> boune to carbonates> > exchangeable. Compared with light and heavy REE, the medium REE(Eu, Sm, Tb) had relatively low percentages in the residual form and high in the forms which are bound to organic matter and Fe-Me oxides. The water bodies of the Wuhan section of the Changjiand River had not been polluted by REE. 
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    OBSERVATION AND CONSIDERATION ON THE GELIFLUCTION IN THE ALPINE PERIGLACIAL ENVIRONMENT OF THE TIANSHAN MOUNTAINS
    Liu Gengnian, Xiong Heigang
    1994, 49 (4):  353-362.  doi: 10.11821/xb199404010
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    Field survey and laboratory analysis have been conducted to research the gelifluction in the alpine periglacial environment of the Tianshan Mountains since 1990. The gelifluctions distribute at 2500─3600 meters above sea level. on the northward slope with slope angles of 10°─31°. The length of the gelifluction ranges 7─28. 4 meters. the width 6─30 meters and height 0. 7─4 meters.Most of the gelifluctions have lobate forms with a ratio of length to width less than 1. and a few of them have tongue forms with length to width ratio greater than 1. The slope gradient of the steep front of the gelifluctions ranges 27. 5°─85°.Forming and developing in active layer of the alpine permafrost zone. the gelifluction is mainly forced by gravity and freeze─thaw action. Based on the data from field pitting and laboratory analysis. it shows that grain─size and water content are stratified in the gelifluctions. The debris in gelifluction is oriented parallel to ground surface. The permafrost table under active layer forms a water─proof plane and offers a sliding plane for gelifluction.The moving rate of the gelifluction is measured at 2 800─3 600 meters above sea level where the mean annual temperature ranges-3℃--5. 3℃ and the mean annual percipitation ranges 430-850 mm. The surface moving rate of the gelifluction is 2. 1─18. 77cm/a. and the mean rate is 11. 14cm/a. The maximam front advancing rate of the gelifluction is 6. 76cm/a. and the mean rate is 1. 86cm/a. It shows that the surface moving rate is greater than that of the front advancing rate.The mean advancing rate of the middle part is 3.1cm/a, while the sides is 0. 83cm/a. This shows that the middle part moves more actively than th both sides. 
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    WEST SCHOOLS OF URBAN STUDY AFTER THE SECOND WORLD WAR
    Gu Chaolin
    1994, 49 (4):  363-370.  doi: 10.11821/xb199404011
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    This paper makes a systematic exposition of Schools of urban study after the second world war,including their forming processes,theories and approaches and new progresses.This schools are :the ecological approach,neo-classical approach,behavioural approach,humanist approaches,Marx’s approach,neo-Weberian approach,new conservatism,structuralism,postmodernism and Fordism.These west schools of urban study after the second world war can be divided into three groups.The first group includes the ecological approach,noe-classical and behavioural approach, which formed in 1960s. The second group consists of new-Marx’s approach,neo-Weberian approach and humanist approaches and prospered in 1970’s.The last one is composed of new conservatism,structuralism,postmodernism and Fordism (including high-Fordism,late-Fordism,post-Fordism). 
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