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    15 January 1990, Volume 45 Issue 1 Previous Issue    Next Issue
    GLACIER RECESSION AND LAKE SHRINKAGE INDICATING THE CLIMATIC WARMING AND DRYING TREND IN CENTRAL ASIA
    Shi Yafeng
    1990, 45 (1):  1-13.  doi: 10.11821/xb199001001
    Abstract ( )   PDF (810KB) ( )   Save
    Mass balance observations on Urumqi River, No.l Glacier and Tuyuksu Glacier in Tian-span show a large deficit during the 1980's as compared with the decades before. The Qinghai Lake in Northeastern Qinghai-xizang (Tibet) Plateau and the Issyk-kul Lake in Soviet Tianshan have been continuously shrinking during the past few centuries. Since the maximum of the Little Ice Age which occurred mainly in the 18th century, glaciers have decreased in area by aboue 44% in the Urumqi valley. These data and other evidence of glaciers, lakes, etc. clearly indicate that the climatic warming and drying tendency grows stronger in this century and would pos-sibly persist to the early decades of next century. T'he growing greenhouse effect due to the incr-ease of CO2 and other related gases will enhance this tendency in the near future. However, should the high temperature period of the early and middle Holocene reappear, the climate mi-ght become humid.
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    DR. ZHU KEZHEN'S (CHU COCHING'S) CONTRIBUTION TO THE RESEARCH WORKS ON PHENOLOGY
    Wan Minwei
    1990, 45 (1):  14-21.  doi: 10.11821/xb199001002
    Abstract ( )   PDF (558KB) ( )   Save
    Dr. Zhu(Chu) is the leader of the research work on Phenology in China. His research works on Phenology in China can he divided into three stages. 1. The first stage was from 1921 to 1931, when he studied ancient and modern phenology in China, and observed the seasonable naturel phenomena by himself. 2. The second stage was from 1931 to 1940, when he worked on establishing phenological observation networks all over China. 3. The third stage was from 1950 to 1973, when he established a new phenological observ-anon network. He made greater contribution to the research works on Phenology in China.
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    THE EVALUATION ON CLIMATIC INFORMATION IN THE HISTORICAL LITERATURES
    Ge Quansheng, Zhang Peiyuan
    1990, 45 (1):  22-30.  doi: 10.11821/xb199001003
    Abstract ( )   PDF (546KB) ( )   Save
    This paper documents methods of evaluating the climatic information extracted from Ch-inese historical literatures. Relevant sources include local gazettes, official histories, memorial to the emperor and personal and private writings. Some indexes has been developed to modify climatic information in three aspects, they are: the time interval between the climatic event occurred and when it was recorded, the distant between the event and where it was recorded, and the ability in language of the writer's explanation. After some numerical treatments, it shows that:(1)The realiability of climatic informa-tion is not only determined by the accuracy of the data, but also by the distribution and resolu-tion of the data. (2) The more grades divided, the more uncertainty will appears. (3) The lar-ger variance schedulled, the more information would be available.
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    ON THE ALLOCATION OF COTTON PRODUCTION BASE IN XINJIANG
    Xu Peixiu, Zhang Yunsheng, Wang Lan
    1990, 45 (1):  31-40.  doi: 10.11821/xb199001004
    Abstract ( )   PDF (702KB) ( )   Save
    Xinjiang is one of major cotton production regions in China. Its natural conditions as well as production traditions have been analysed. Considering the land and water resources, the cot-ton production in Xinjiang might reach at 0.533 million hectare and 0.5 million ton. A sugges-tion of spatial allocation strategic has been proposed. 1) The plantation of upland cotton (G hirsutum) with high quality and long-staple cotton (G barbadeuse) should be emphasised in sou-th Xinjiang; A specialized cotton production b0lt along the Yarkant River and the Tarim Riv-er would be established. 2) The production areas of cotton with high quality in north Xinjiang should be strengthened and improved; In the area of Mosauwan-Xiayedi-Chepaizi a specialized cotton production belt will arise. 3) The ultra long-staple cotton plantation region in east Xin-jiang should be steadily enlarged.
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    PHYSICO-GEOGRAPHICAL REGIONALIZATION AND REGIONAL DEVELOPMENT OF GUIZHOU PROVINCE
    Cai Yunlong
    1990, 45 (1):  41-55.  doi: 10.11821/xb199001005
    Abstract ( )   PDF (972KB) ( )   Save
    Not one previous scheme of physico-geographical regionalization has divided China into the lowest regional units. An important cause of this is that the genesis theory, upon which the Pra- cedure of division "from top to bottom" is based, can suit only for analysis of larger-scale ter-restrial differentiation. This paper takes the procedure of grouping "from bottom to top" on the land classification map as a necessary supplement. Thus the scheme of physico-geogra-phical regionalization of China is implemented thoroughly in Guizhou province and the two kinds of research, i.e. land classification and physico-geographical regionalization, are integra-ted. Guizhou province is situated in the southwestern China. It has an area of 176636 sq km, which comprises 1.84 per cent of the whole land of China. Its climate belongs to monsoon type of plateau humid subtropical zone with more overcast and rain and less sunshine. Geomor-phologically it is an erosion karst plateau and has various types of landforms. It is rich in water and waterpower resources. Its soils are mainly yellow and calcareous types. It has the vegetation of evergreen broad-leaved forest with characteristics of lcarst habitat. Most part of the Guizhou province belongs to the Natural Region of Guizhou Plateau, and others to the Na-tural Region of Sichuan Basin and Natural Region of Yunnan Plateau respectively. The Gui-zhou Plateau Region can be divided into five subregions, i.e. the Northern Mountains and Gorges, the Eastern Mountains, and Hills, t:he Southern Low Mountains and Valleys, the Wes-tern Mountains and the Central Hilly Plateau. Every subregion comprises many natural areas which have a unique land structure. In Guizhou province, the main factors of land differentiation are pattern of basic land-forsm, elevation above see level, surface material and human activity. They comprehensively reflect geomorphology and soil-vegetation. According to these indexes and taking land system as mapping unit, five land types at the first order and seventy-eight land types at the second order can be distinguished. Then, ranges with relative identical land structure may be grou-ped into natural areas. Thirty two natural areas are grouped. "Chey are regrouped so that the boundaries of natural subregions and regions are. determined. Conforming to the development of economic situation of China, the application of physico-geographical regionalization ought to be expanded from "agriculture" to "regional develop-ment and territorial readjustment". This paper analyses features of natural resources and lo- canon conditions, compares them with prohlems of present development, and suggests the fu-ture development strategies for every subregions and areas.
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    QUANTITATIVE PROPERTIES AND CLASSIFICATION MODELS OF BRANCHING ESTUARIES
    Jin Yuanhuan
    1990, 45 (1):  56-67.  doi: 10.11821/xb199001006
    Abstract ( )   PDF (651KB) ( )   Save
    An estuarine branching system has four skinds of vertices, i.e., forks, junctions, knots and outlets, and thirteen kinds of links correspondingly. Some concepts of theory of topology and graphs have been introduced in this paper to make further expression quantitatively to the topo-logic properties of estuarine branching system. After redefining the: recombination factor, or the ratio of number of junctions and knots to number of forks, this paper points out the recomb- ination factor varies from zero to one nearly, with the extent of bifurcating and rejoining of an estuary. Ninteen natural branching estuaries have been studied in details. The results show us the recombination factor ranging from 0.25 to 0.93, which is related to various kinds of vertices and links, deltaic area, the exterior angle of an estuarine branching system to a certain extent. The most frequently appeared vertices in a natural estuarine branching system are forks and outlets, while links are ff, fj and fo. Tlhe most scarcely appeaxed vertices are knots, while links are kk and ko. Finally, in accordance with the principle to combine the cause, plain feature and channel changing characteristics together of a branching estuary. this paper proposed that four branch-ing models: less-branching, much-branching. complex networks and wandering. The properties of topology of each model have beem studied quantitatively.
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    THE RELATIONSHIP BETWEEN THE WINTER MONSOON ACTIVITY OVER EAST ASIA AND THE EI NI袿 EVENTS
    Guo Qiyun, Wang Risheng
    1990, 45 (1):  68-77.  doi: 10.11821/xb199001007
    Abstract ( )   PDF (463KB) ( )   Save
    In this paper the relationship between the interannual variations of East Asial wi-nter monsoon and the El Ni?o events is examined based on the monthly mean sea level pressure (SLP) data set over the greater parts of the globe (50°S一60°N),, auk the sea surface tempereture (SST) in the Equatorial Eastern Pacific (0°-10°S, 180°一90°W) from 1951 to 1986. The: main results are as follows: (1) Significant correlations between the SST in the Equatorial .Eastern Paeific} and the SLP during predominating of the East Asia winter monsoon (Oct.-Mar.), occur in southern Asia and western Pacific (positive correlation) northern Austra-lia (positive correlation) and Aleutians Island (negative correlation). (2) The variations of the SST lead that of the SLP in one or two seasons. The greatst correlation is found .between the SST in November and the SLP in the mo-nths preceded and followed. (3) In the winters (Dec. of 0 year to Feb. of+1 year) of an E1 Ni?es year, the path of cold wave over East Asian continent migrates to the east in comparing to the normal and the precipitations increase in South China. On the contrery, in an anti-E1 Ni?o year the path of cold wave moves to the west and the precipitation decreasesin in South China.
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    THE CONSTRUCTION OF THE SHANGHAI PORT AND ITS SEA-ENTERING CHANNEL, INFLUENCED BY THE SEDIMENTS AND THE FLUVIAL PROCESSES AT THE CHANG3IANG RIVER ESTUARY AND THE HANGZHOU WAN
    Lin Chengkun
    1990, 45 (1):  78-89.  doi: 10.11821/xb199001008
    Abstract ( )   PDF (856KB) ( )   Save
    The Changjiang Estuary in an estuary characterized by immense runoff and strong tide. Its average discharge is 29 400m3/s, in time of flood-tide, it can be as great as about 5.3 X lO9m3. The average tidal range at the river mouth is 2.66 m. The amount of sediment is 4.605 X 108m3/a. The dynamic interaction of these two strong forces leads to from the braided pattern in the Changjiang Estuary. It is divied into the South and the North Branches by the Chongm-ing Island. The South branch is likewise subdivided into two waterways, the South Waterway and the North Waterway by the Changxing and the Hengsha Island, and furthermore the Smr th Channel and the North,Channel by the Jiuduansha sandbars. Now we regard the braided channels as the North Waterway and the North and the South Channel. At their estuaries, there exist the mouth bars and the natural water depth of them are limited to about一5.8m of the base level of the Wuson (all those following are of this base level). At the present, the North Chan-nel is sea-entering channel of the Shanghai port and Harbours of the Changjiang Delta. The North Channel dredge to一7m, material dredging from the channel amounts to 1.8 X 107m3/a. A 10 000 ton carrier may pass throuth this channel with the tide. The fluvial processes of the North and the South waterway appear primarily to be thriving and degenerating alternatively. A study of historical records and topographic maps of the Changjiang Estuary reveals that on an average the waterway changed its position with a frequence of about once in twenty years. The Hangzhou Wan is a typical funnel-shaped estuary with strong tide from the mouth to the apex. The reduction of width is 80km, while the increase of tidal ramge is twice as much. The average tidal range is 5.45m, the maximum tidal range is 8.93 m. The annual average dis-charge of Qiantangjiang is only 921 m3/s, while the average discharge of flood tide may reach 190 OOOm3/s. The formation of a funnelshaped estuary of a deltaic estuary is due to the less qu-antity of sediment of the Hangzhou Wan with an average amount of merely 5.328 X 107 t/a, of which clay sediment takes up 76.2% of the total. The Hangzhou Wan is divided into the South and the North Branches by the Qiqu Archiplage. The average natural water depth is about一9.11 m, The less quantity of sediment and very fine particle are not liable to settle down and sa the waterways are quite stable. The change of channel is rather slow. At the present, these two wZterways are not developed as yet. The Shanghai Port, the biggest port of China, has at present, not enough passing capacity. Inorder to solve this difficulty, some new ports must be built. According to sedimentation, flu-vial processes and water depth of sea-entering channel and port-sites, the author suggests the best port-sites at Jinshzui and Qiyikou which are selected from the Hangzhou Bay and the Ch-angjiang Estuary. For the former, the berth will be limited from 35 000 to 50 000 ton-class and for the latter from 10 000 to 20 000 ton-class. The passing capacity of the main channel at the Changjiang Estuary is affected by the dr- edging difficulty. To solve this problem, in order to make full use of the main entering citan-nel, an auxilliary channel of South Branch of the Changjiang Estuary and a sea-entering eh-annel at the Hangzhou Wan must be opened up at the same time in the nest decade.
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    THE THEORY OF GOODS AND MATERIALS FLOW FIELD AND ITS APPLICATION IN ECONOMIC ANALYSIS
    Wang Zhiguo
    1990, 45 (1):  90-101.  doi: 10.11821/xb199001009
    Abstract ( )   PDF (786KB) ( )   Save
    The author held that the moving of goods and materials flow(GMF) which joins man-kind producing or dwelling site in a certain order to form a."field"—GMF field(GMFF). This GMFF is a basic form of material connections of mankind activities. It brings about the most general prooess of development of society and productive forces. In the first part, a concept system and analysis method about GMFF have been given. There are main concepts: the GMFF, the intensity of GMFF(IGMFF), tile potential of GMF(PGMF), and the density of GMF(DGMF). The GMFF theory can analyse the problems about economic and social development, especially the geographical, the communication and trarsspnrtations economy in its corresponding area. In the second part, some actual samples have been analysed by using the theory and me-thod: 1. the evolution of GMFF, interrelation between GMFF and the economic development level and the statistical law around 2000 yeas in China. 2, the distribution of GMFF, economic development level and productive forces and their interrelations in China.
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    A STUDY OF THE VARIATION OF DRYNESS/WETNESS IN BEIJING AND ITS FOPECASTING EXPERIMENT
    Huang Jiayou
    1990, 45 (1):  102-109.  doi: 10.11821/xb199001010
    Abstract ( )   PDF (488KB) ( )   Save
    Water supplement is very important in Beijing where drought has frequently occurred since the 1960s. The climatic prospect about drought or flood is studied in this paper. The study will focus the attention on three problems: first, how is the climate situation about dryness and wetness described? Second, how do they vary with time? Third, which method will be better for forecasting them? The yearly dryness/wetness index for describing climate situation is proposed in this pa-per. It is the sum over twelve证the monthly moisture index which is the standardized mon-thly precipitation. It is more meaningful a.nd representative than the index of yearly preci-pitation. The series of the yearly dryness/wetness index in Beijing for the period from 1869 to 1987 have been built. Furthermore, it is investigated using power spectral analysis and variance analysis for its characteristics of the periodic variation, and is found that the main periods are 5-yr and 2Z-yr. The period patterns, for 5-yr and 22-yr are extracted. by means of the period pattern method proposed in this paper. The patterns are represented by the eigenvectors of the cross-product matrix of the period matrix whose elements are from the original series arranged as an array according to the length of the period. The forecasting of the dryness/wetness index is completed through the regression equation in which the period patterns are considered as the predictors. The results show that the water supplement wi}1t probably get improvement in Beijing by the end of this century.
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    QUANTITATIVE STUDY OF THE STAGE AF GEOMORPHOLOGICAL EVOLUTION
    Li Qiang, Lu Zhongchen, Yuan Baoyin
    1990, 45 (1):  110-120.  doi: 10.11821/xb199001011
    Abstract ( )   PDF (650KB) ( )   Save
    This paper puts forward the integral value of erosion of threshold as a quantitative stan-dard to divide the stages of geomorphological evolution which inherits and develops the classical theories in geomorphology. The advantages by using the integral value of erosion are as follows: (1) putting the stage of geomorphological evolution into the concept of open system; (2) avoiding the uncertainty caused by Strahler's Area-Altitude analysis to divide the stages of geomorphological evolution; (3) setting up the quantitative relation between the stages of geomorphological evolution and matter movement of drainage basins; and (4) distinguishing the natural and accelerating erosion of drainage basin. By analyzising and calculating the drainage basins which belong to rolling gully area on Loess Plateau, the conclusions are reached that the drainage basin enters maturity from youth, when the integral value of erosion equals 0.30, in which the evolutionary time was 70 thousand years ago and erosional modulus was 7008 t/km2. a; the drainage basin will enter old age from maturity when the integral value of erosion equals 0.70, in which the evolu-tionary time will be 72 thousand years later from now on and erosional modulus will be 7008 t/km2. a only for natural process. The percentage of accelerating erosion in rolling gully area on Loess Plateau is 30% now.
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