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  • 1995 Volume 50 Issue 4
    Published: 15 July 1995
      
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  • TOWARD ESTABLISHING THE CONCEPT OF PHYSICAL URBAN AREA IN CHINA
    Zhou Yixing, Shi Yulong
    1995, 50(4): 289-301. https://doi.org/10.11821/xb199504001
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    It is generally agreed that human settlements are classified either as urban places or as rural places,In urban studies,one has to deal with the relerant materials in the right way so as to reflect the reality of urban area.Urban areas may be conceived as administrative, functional and physical entities. This paper make a detailed analysis on the various drawbacks of the continued use of adiministrative area in the division of urban and rural area in spite of the serious discrepancies between urban administrative boundaries and the real’ urban space in China, Almost the administrative area of all cities and towns are much larger than the urban built-up area. As a result, vast rural areas and large agricultural population were included in the urban count. Here lies the principal difference with western countries. Obviously, it is difficult if not impossible for us to solve the contradiction by reducing the adiministrative area of a city or town. The authors believe that to solve this problem, it is essential to establish the concept of physical urban area with both adaptability to Chinese conditions and international comparability and make it the basis of urban-rural division and statistics.It is proposed that physical urban area in China can be delimitated in terms of three criteria,prescribed minimum population scale, degree of nonagricuturalization and population density, and the names of citied area or townized area can be given as the counterpart of urbanized area in the United States.The administrative area of a city or town in China consists of two parts: urban district and suburban area. The combination of the two parts is very conplex. For this reason, the key to put our scheme into effect is the classification of types according to the different relations between the two parts.Based on extensive research, the authors find that three factors bring about twelve types. AIa and AIb of them are the most basic types,All these types have their own quantitative standards.After understanding these types, the delineation of the physical urban areas become fairly easy according to the flow diagram(Fig.1).Eleven samples, except one type which is not find,are cited in this paper (Fig.2).
  • POSSIBLE IMPACTS OF SEA LEVEL RISE ON MAJOR PROJECTS AND URBAN DEVELOPMENT IN THE COASTAL AREAS IN CHINA
    YangGuishan, Shi Yafeng
    1995, 50(4): 302-309. https://doi.org/10.11821/xb199504002
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    The coastal plains are the regions with dense population and well-developed economy in China. where there are over thirty middle or big cities and nearly twenty important harbors.including Tianjin, Shanghai and Guangzhou etc. Due to land subsidence and other factors, relative sea level rise of these areas can be 2-3 times of the global mean value in the mid-21th century.So the coastal plains of China will be one of the regions which are the most vulnerable to future sea level rise in the world. Through the typical researches on the old Huanghe Delta near Tianjin, the Changjiang Delta and its adjacent area and the Zhujiang Delta,this paper analyses the adverse impacts of a 50 cm sea level rising on coastal defense, water conservancy and harbor projects, as well as urban water supply, flood control and tourism in the coastal areas in China.The research results show that, acceleated relative sea level rising will cause marked decline in the function of the various coastal defense and water conservancy projects and endangerseriously the functional working of more than half of sixteen major harbors. Meanwhile, it will also influence urban development through deteriorating water quality, aggravating the tasks of urban flood control and damaging tourism beaches. Tianjin, Shanghai and Guangzhou would be seriouly affected.
  • THE THANATOCOENOSIS AND ENVIRONMENT EVOLUTION IN THE ZHUJIANG DELTA
    Huang Zhenguo, Zhang Weiqiang, Chen Junhong
    1995, 50(4): 310-323. https://doi.org/10.11821/xb199504003
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    The modern environment in the estuary area of the Zhujiang River can be divided into six types:the delta plain, shallow,tidal estuary, delta front slope. prodelta and shallow sea.The thanatocoenosis composed of foraminfera, ostracoda, diatom and shell in different environmental unit is enumerated.Comparing the thanatocoenosis occured in the Quaternary system with that found from modern environment, two maps of paleoenvironment during the transgression period of Q32-2 and Q24 in Zhujiang Delta are produced respectively. The authors suggest that the environment during transgression period in a estuary includes three units, namely the typical transgression area including prodelta and delta front slope, the area involved by transgression including tidal estuary and shallow, and the area influenced by transgression which is delta plain.According to the feature of fossil group found in the profiles which have been dated,the transgression scope during the period of Q32-2 was mainly distributed along the western and eastern sides of Lingdingyang, but a tidal estuary was involved northwest forward to the central part of the delta such as Daliang and Fushan. There were two estuaries in the southern part of the delta but they were not involved northward so far from sea. During the transgression period of Q24,the paleoenvironmental feature was different from that of Q32-2 mentioned above. An area of about two-thirds of the delta had been submerged by sea water, resulting an extensive scope of prodelta. The limit of prodelta at that time was ranged by a strike of NE-SW along the line of Huangpu-Panyu-Daliang-Xingtan-Nantou-Lile. In other words, the transgression of Q24 is the greatest one since Late Quaternary in the area of Zhujiang Delta. moreover, there were two tidal estuaries which involved to Nanzhuang, Fushan and Zhoubiao north to Guangzhou, Therefore the scope of delta lain was quite small at that time.As for the transgression of Q2, the authors consider that it may be impossible because the sand-pebble deposits found in the northwestern margin of the delta are of alluvial and proluvial features,and the marine sediments of Q2 have only been found on the shelf of the basin of Zhujiang River mouth at an altitude of about -100m at present.
  • RESEARCHES ON MUNICIPAL ADMINISTRATIVE CITIES IN YUAN DYNASTY (AD 1260-1368)
    Guanghui Han
    1995, 50(4): 324-334. https://doi.org/10.11821/xb199504004
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    The municipal administrative system in ancient China appeared in the mid-12th century, developed and matured in the 13th and the first half of 14th century. The main sign was the establishment of Jingxunyuan (municipal council) and Lushisi (municipality) . During the Yuan Dynasty(A. D. 1260-1368) there appeared 123 municipal administrative cities, of which 102 were developed steadily. The special administration on cities was both the objective demand of urban development and the result of urban expansion and functional integration. Therefore, the appearance of such number of municipal administrative cities is the important sign of the then leading status of the Chinese urban development in the world. In this paper. the systematic research is focused on the functions of municipal organizations and the scales and characters of municipal administritive cities in Yuan Dynasty.Jingxunyuans (municipal council) were founded only in the two capital cities: Dadu and Shangdu, where municipal magistrates, Just like those in adjacent capital counties, administrated the civil affairs, taxations and corvees of urban residents. Lushisis (municipality), whose administrative level were lower than that of Jingxunyuans, were generally founded in Zongguanfus (great regional capital) or Luzhis (provincal capital). Magistrates just like those in adjacent provincal capital counties were also appointed, and they administrated the same issues as those of Jingxunyuan magistrates. Commanded by Lus (province) and Zongguanfus, and paralleled with suburban Zhous (small cities) and counties, Jingxunyuans and Lushisis were independent municipal administration agencies in Yuan Dynasty.Having been regional political, cultural and educational centers. municipal administative cities developed into regional economic centers with the intensification of social division of labour and the development of urban economies. This can be proved by the economic statistics of Jiqing (Nanjing at present), Guangzhou (Canton). Zhenjiang and Jiaxing.The urban population varied greatly in different cities owing to distinct economic, social and physical factors. In the late Yuan Period (about A. D. 1345), the population in Jiqing reached 140 000, Guangzhou and Jingjiang reached 70 000, Jiaxing reached 40 000. They were the typical different scale cities. As a country with diversified nationalities, Yuan Empire made complex nationalitical and household structures in municipal administration cities. For example, the population of municipal administrative cities in South China were mainly Nanrens (southern people).while richer northern migrators constructed a certain ratio.With regard to the regional geographical distribution of municipal administrative cities, we can conclude that the two capitals in which Jingxunyuans were set up were located at the edge of the north agriculture-stock raising interlocking area; more than 100 cities with Lushisis were in the following two regions Huabei (northern China) and middle and low Yangtze River Basin. Between the two regions there was a obvious empty area. This geographic character of municipal administrative cities is the result of the long historical process of political, social, economical and migrational development.
  • RIVER CHANNEL PATTERN CHANGE AS INFLUENCED BY THE FLOODPLAIN GEOECOSYSTEM:AN EXAMPLE FROM THE HONGSHAN RESERVOIR
    Xu Juongxin, Shi Changxing
    1995, 50(4): 335-343. https://doi.org/10.11821/xb199504005
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    The floodplain geoecosystem can be defined as a system composed of factors such as floodplain morphology,alluvial materials,soils, groundwater and vegetation. A strong coupling relation between the floodplain geoecosystem and the channel system is established by the matter and energy fluxes through their interface.After the construction of the Hongshan Reservoir,a dramatic change of the upstream-reservoir floodplain geoecosystem has taken place.Before and after the reservoir construction,the succession of the floodplain geoecosystem can be generalized as 3 stages, namely,the semi-desert geoecosystem,the marsh and swamp geoecosystem,and the agricultural ecosystem.After the upstream-reservoir floodplain geoecosystem turned from a semi-desert to a marsh and swamp,the dynamics of matter exchange between the floodplain and the channel has been changed significantly,leading to a strong reform of the composition of floodplain material.Before the growth of aquatic and marsh weeds,the clay content in the bed material was very low, ranging from 5%to 7.5%.After dense weeds appeared, the water flow velocity declined greatly,a factor favourable to the fine sediment deposition. So the clay content of the bed material increased rapidly up to 45%on average.Adjusting itself to accommodate the reworked channel boundary conditions, the channel reforms its bed morphology and tends to re-establish the balance among the material, process and morphology. Consequently, the pre-dam wandering braided channel pattern has been gradually transformed to a meandering one. With the narrowing of the channel due to the strong sedimentation induced by aquatic and marsh weeds growth, the width-depth ratio tends to be much smaller,associated by a lower and lower degree of braiding. Finally the channel becomes a singethread one. In the meantime, the channel sinuosity increases continuously, from 1.06 in 1961to 1.27 1n 1985, and the channel is turning to a meandering one.
  • THE EVOLUTION AND OPTIMIZATION OF THE SPATIAL STRUCTURE OF MILK OF PRODUCTION IN SHANGHAI
    Guo Balin
    1995, 50(4): 344-352. https://doi.org/10.11821/xb199504006
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    The spatial structure of milk production in Shanghai has three hierarchies:the circular distribution, the system for milk traffic and the collective-distributive network.The circular structure, centering round urban districts, divides milk production into three different circles based on structures and functions:the consumption center of fresh milk in the urban districts,the processing circle for dairy products in the rural-urban fringe area,the production circle of fresh milk in the suburb. The circular structure is the result of mutual effects of milk production and regional condition. The milk productions are connected to a whole by a milk traffic.The system for milk traffic is constituted by the original region of raw milk and dairy factory and the supply region of fresh milk.Its sector spatial character and spatial arrangement of formation in regular sequence reflect the circular sturcture of milk production.The original region of raw milk(supply region of fresh milk)is constituted by a series of collective regions of raw milk(distributive region of fresh milk).They are the two entirely diffrent areal cells functionally between the collective-distributive networks of milk production.They are service regions of collective-distributive stations of milk.The spatial structures of all hierarchies are connected and limited each other and their evolution has a synchronism. The evolution of spatial structure of milk production is circle to move out. It propels the recomposition of the system for milk traffic and the restructure of collectivedistributive network. The contradiction between the expansion of the scale and the limited capacity of the region is the impetus of evolution of the spatial structure of milk production. The difference in locational superiority causes the internal disintegration of spatial structure of every hierachies of milk production.There are three points for optimization of spatial structure of milk production in Shanghai:1.The aim of adjustment of circular structure should be to fully play the locational superiority in all the places.2. Adjustment of the system of milk traffic should be practiced together with productionsale regionalization, so as to improve transportation efficiency.3. The optimization of collective-distributive network should be distributed resonably on the base of the suitability and service radius of the collective-distribtitive stations of milk. the production density of raw milk and the consumptive density of fresh milk in all the pleces.
  • A STUDY ON TOURIST DEVELOPMENT OF KARST CAVES
    Bao Jigang
    1995, 50(4): 353-359. https://doi.org/10.11821/xb199504007
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    China is a country with the largest area of carbonatite and the total is 1300 000 square kilometers. Karst caves are found all over the country, especially in Yunnan.Guizhou, Guangxi, Guangdong, Hunan, and Zhejiang provinces. At present, there are about 200 Karst caves open to tourists.Karst caves are a tourist resource with a lot in common and little individuality. As a result, the rate of repeat visits is low. After development,the spatial competition among caves is very strong. As far as the same region is concerned, it is usual for a resource with a high quality and a good location to replace that with a high quality and a poor location. In general. Karst caves can hardly have a nationwide attraction and have only a provincial or regional attraction.The life cycle of Karst caves is very unique which does not have exploratory and involvenment stages. It goes into development stage directly. often having a tourist peak in the first year. An isolated cave has a very short consolidation stage and short stagnation stage and comes quickly to the decline stage. If it is in line with a tourist attraction or is part of a famous scenic spot, its consolidation and stagnation stages will be longer and the decline stage will come much later.Tourist development of Karst caves can be divided into three types (1) Tourist development of isolated Karst caves.(2) Tourist development of Karst caves with a positive neighboring effect. This type can be divided into 4 subtypes:a)The cave is of high quality and is near famous scenic spot.b) The cave is not high in quality but is near a well-known tourist resort.c) The cave is very good in quality with a famous scenic spot that has low tourist capacity.d)The cave has intervening opportunities. (3) Tourist development of Karst caves in well-known scenic resorts. The present paper uses a lot of cases to demonstrate the conditions and characteristics of the tourist development of the Karst types mentioned above.
  • THRESHOLD VELOCITIES OF SAND-DRIVING WIND IN THE TAKLIMAKAN DESERT
    Chen Weinan, Dong Zhibao, Yang Zuotao, Han Zhiwen, Zhang Minli, Zhang Jiashen
    1995, 50(4): 360-367. https://doi.org/10.11821/xb199504008
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    Sand-driving wind is one of the important factors in the study of aeolian sand movement, therefore it is of great significance to determine the threshold velocity accurately for the estimation of sand transport rate and recommendaton of proper sand control measures. On the basis of field observation this paper attempts to make out the fluid threshold and impact threshold and adapt them for different heights and time durations. Consequently, the wind data derived from the meteorological observatory will be more efficiently used in the study of sand movement. By means of the work mentioned above, the following results have been reached.At the height 2m above ground surface.for naturally mixed sands,the instant fluid and impact threshold velocities are 6.0 and 5. 0m/s respectively,equivalent to one minute averages of 5.2 and 4. 3m/s respectively. While averaging on ten minutes duration, the fluid and impact threshold velocities are 5.7 and 4. 7m/s respectively. Both fluid and impact thresholds have been adopted for the height of 11.4m (the height of anemometer tower) at which the instant velocities for the former and later are 7.8 and 6.63m/s respectively, equivalent to 7. 4 and 5.97(≈6.0)m/s of ten minute averages.
  • GEOMORPHOLOGY RESEARCH ON THE LARSEMANN HILLS,EAST ANTARCTICA
    Li Shuanke
    1995, 50(4): 368-376. https://doi.org/10.11821/xb199504009
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    The Larsemann hills are a series of gneiss islands and peninsulas extending into Prydz Bay, with an ice free area of approximately 200 km2 at 69°21′S 69°28′S and 76°00′E 76°25′E on the Ingrid Christensen Coast of Princess Elizabeth Land in East Antarctica. The area lies in the pole permafrost zone, aeolian action is very frequently and generally. The characteristics of modern landform are controled by periglacial processes. Because of the short history of ice free area and the relatively stable older Archean Shield, the weathering process is very weak with mainly mechanical weathering, especially frost process. The major geomorphic types consist of aeolian landforms. periglacial landforms,glacial landforms, lake landforms, coast landforms and geological structure landforms, etc. The deposited landforms have not been developded successfully and fully. The landforms on the west hills are relatively young. The direction of glacial retreat is from NE to SW, according to the distribution of glacial relics, i. e. , moraines and rub traces. Islands. peninsulas and ice-land transition zone are three geomorphic regions.
  • THE NEW RECOGNITION OF THE CHANGES IN DRAINAGE NETWORK AT THE UPPER REACHES OF THE HUTUO RIVER
    Pan Mao
    1995, 50(4): 377-384. https://doi.org/10.11821/xb199504010
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    In this paper,three contentious questions on the changes in drainage network at the upper reaches of the Hutuo River were discussed emphatically: (a) the change of the course of the Yangwu River, (b) the bandoned river course in the Qicun Valley; (c) whether the Hutuo River flowed southward into the Taiyuan Basin. Following results were obtained form the investigation.(1) The Yangwu River, a tributary of the Hutuo River, was not a pirate, capturing an ancient southwestward flowing river. Its main stream and tributaries were developed along two sets of faults trending NW SE and NE SW respectively.(2)During the geological period, probably throughout the Pleistocene, the Qicun Valley and the Jiehepu Valley were two co-existing branch courses of the Hutuo River.Of course. it is possible that one of the two branches was the main course of the Hutuo River,while another one was abandoned in the short time. Finally, the main course was abandoned because it was totally filled up by deposits from the mountains on the west side.(3) The Hutuo River Gorge across the Taihang Mountain was antecedent to the uplift of that mountain which occured mainly at the end of pliocene. The Shilingguan wind gap which is situated just to the south of the Xinzhou Dingxing Basin was a relic valley formed by an ancient southwestward flowing river which existed before the basin along the upper reaches of the Hutuo River was formed. The Yuzi gap, which consists of loose sediments, may be another relic valley formed by the ancient river, but not by the Hutuo River.