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    15 September 1994, Volume 49 Issue 5 Previous Issue    Next Issue
    DISTRIBUTION OF PORTS IN CHINA
    Guo Laixi
    1994, 49 (5):  385-393.  doi: 10.11821/xb199405001
    Abstract ( )   PDF (623KB) ( )   Save
    Ports,as doors of the country opening toward the world,is playing double roles making a bridge between the domestic market and the overseas market and defending state sovereignty.In China,the ports are some seaports,railstations,passways,and airports where the goverments permit passengers,goods and vehicles to pass through and some facilities (e. g. frontier inspection stations.customhouse,harbour superintendency administrations and quarantine stations for human being,animals and plants,etc),infrastrucutre and administration offices are established.This paper includes five sections: (1)Classification and function.China’s ports can be divided into the state ports and the localports based administrative level and seaports.airports and local ports based on modes of transportation.(2)Fundamental elements of ports.A basic port includes the external transportation system,the foreign trade system.the supervisory and testing system,the service system and the comprehensive administrative system.(3)Allocation of ports and regional development.(4)Distribution of China’s ports.The author discussed mainly the seaport system along the coast,the trading port system along the interior border,the waterport system along the Changjiang River(Yangtze River).(5)Some suggestions for the development of China’s port system.They are :(a)The establishment of ports must depend on the development of external economy.international passways,airline networks.(b)The function of ports in the interior area and along the Changjiang River(Yangtze River)should be diversified.(c)The port planning must march the urban construction.
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    INTERNATIONAL COMPETITION AND COOPERATION OF CHINA’S BOHAI SEA RIM AREA UP TO 2000
    Cao Yong
    1994, 49 (5):  394-402.  doi: 10.11821/xb199405002
    Abstract ( )   PDF (565KB) ( )   Save
    The East coastal zone is China’s most important area which engages in international competition and cooperation,and its economic development is now influenced by international factors more and more.The Bohai area,which including Beijing,TianJin,Liaoning,Shandong,and Hebei,is the north part of the east coastal zone.This paper analyses the influences of various external factors,such as geo-economies,international trade,foreign direct investment on the Bohai region’s economic development and makes some proposals of policy-making.1.Regional background and international,domestic environment.Strategic position of the Bohai Sea Rim will be improved gradually.By 2000,it will become the most important strategic economic region and its importance will be superior to the Yangtze River Delta and the south east coastal area because of the following reasons.(1)Japanese economic strategic points will be moved from north America and EEC and south east Asia,where are nowadays Japan’ most important area of investment and foreign trade,to the Bohai Region and Far east area of Russia by 2000.(2)Japanese and south Korean investors always take cities and provinces in the Bohai area as their favorable location when they evaluate the investment environment of the related provinces of China.(3)After Chinese currency(RMB)can be exchanged freely,the location choice of American investment will move from south China to north China.(4)A new way of international cooperation for the Bohai Area has been opened after DPR Korea open its door to outside in a limited way.2.The main characters and problems of international economic linkage and cooperation in the Bohai Rim are its low level of industrial structure and export-import structure.The main export products are low-value added which include textile.raw material,agricultural products,arts and crafts,mechanic and electronic products,whereas the imported products are mainly high value added products,such as mechanic equipments and electronic products.3.To improve the position of the Bohai rim in international division,following industries should be taken as the key industries to develop:communication equipments,computer and micro-electronics,motor vehicles,office equipments,chemical engineering,new energy and materials,and some others.A state export-import bank should be established to help the industries to develop.
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    THE DISTRIBUTION PATTERNS OF SPERMATOPHYTIC FAMILIES AND GENERA ENDEMIC TO CHINA
    Wang Hesheng, Zhang Yili
    1994, 49 (5):  403-417.  doi: 10.11821/xb199405003
    Abstract ( )   PDF (860KB) ( )   Save
    It is a high level endemism of chinese flora with 8 endemic families and 268 endemic genera.This paper deals with the distribution patterns based on their geographical distribution and the relationship with environrnents and the cartographic method.They are classified into 9 distribution patterns and 23 subpatterns,i. e. 1)S.China─S.Yunnan. 2)Yunnan Plateau─S.Yunnan,3)Hengduan Mts.─S.Xizang, 4) SW.China─C.China─E.China,5)SW.China─N.China, 6) C.China─E.China.7) N.China,8)Arid─region of NW.China and 9)Qinghai─Xizang plateau and have been made the statistics of number and the analysis are made.Various disjunctive and vicarious distribution phenomena are introduced in some genera or species endemic to China.3 basic characteristies of distribution patterns and main dispersal routes of endemic genera.i.e.(1).It is unequal in every region distributing mainly in the tropical and subtropical region of the south part of Qialing-Dabei Mts─Changjiang River and appearing 8 abundance centers.(2).It is radial dispersal from SW.China toward all directions and along several routes like to S.China─SE.China,C.China ─E.China,Northern China and S.Xizang.(3).There are various distribution forms as continued,disjunctive and vicarious areal.
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    A STUDY ON MICRO-EROSION OF THE STONE SCULPTURES OF THE LIANG DYNASTY (522-526AD) IN NANJING
    Zhang Jie, Li Shengfeng, Chen Shufan, Yang Tianqi
    1994, 49 (5):  418-429.  doi: 10.11821/xb199405004
    Abstract ( )   PDF (878KB) ( )   Save
    Natural damage to ancient stone sculptures or cultural relicts,especial the biodeterioration,has become a new research topic.The Liang stone sculptures during the Liang Dynasty in the suburb of Nangjing,which are a group of limestone sculptures and inscripted tablets of the Liang tombs,built in the period of 522-526 AD,have been enrolled in the list of National Cultural Heritages of China.The Liang stone Sculptures have been situated in the open air for more than 1400 years since they were built.The damages to them belong to a kind of karst geomorphological phenomena,This paper presents a micro-morphological approach to the study on weathering of the stone sculptures.I. Observation on micro morphology of produced by natural damage.A. Observation in situLiang stone sculptures include stone sculptures of the mausoleums of Xiao Dan,Xiao Hui,XiaoJing and Xiao Xiu,The main types of sculptures are Bixie (a symbolic divine beast as evil-spirits exorciser),ornamental colums and inscripted tablets.The main types of the damage phenomenon can be classified in accordence to section morphology into: a) Solutional fissures and furrows,mainly along the suture line;b) Solutional pits, c) Meandering furrows, distributed on sculpture below the buried surface,d) Selective corrosional features.In order to understand the penetrating character of the fissures,we measured the weathering(solution) fissure along suture line on Xiao Hui’ s Sculpture.The parameters measured included:a) Width of fissure mouth,b) The depth of the fissure with plug gauge of 0. 5mm and 0.1mm,The measured data show a trend that the wider the fissure mouth,the deeper the total fissure.We also calculated the outer angle and the inner angle between the corroded fissures ong rock walls,where the inner angle refers to the angle between rock walls of the fissure from 0.5mm to 0.1mm wide and the outer angle from mouth to 0.1mm wide.The data indicate that:a)Inner angles are smaller than outer angle generally,b) There is a trend that the larger the total depth of the fissure,the larger thd outer angle will be.The main results of the observation in situ are summed up as follows:a) The damage to sculpture surface is mainly due to the solution with several section types,b) The solution fissure formed along suture line is an initial fatal damage,which may cause the disintegration of the whole sculpture,c) There is a difference between the surface damage on the burried line and that below the line.d) There are lichen and algal covered surfaces with obvious biodeterioration.B.Lab ObservationWe identified the epi-and endolithic lichen and alage collected from the sculpture surface.The lichens identified are Caloploca sp.;Collama sp.,Diploschistes actinostomus,Lecanora muralis;and Verrucarin sp.,The algae include Gloeocapsa sp.and the species from the order of Chamaesiphomales and Chroococales.With optical stereo microscape observation,the micro solutional fissures with chasmolithic algae along suture line can be observed.The chasmolithic algae may form the patched solutional pits and the related relict micro steps with a height of about o.1-0. 3mm.Calcite vein often forms a ridge with micro corrosion furrow on both sides.Algal coating may become full of crack with the tension of mucus while in dry season.With observation on certain minor solutional features under Scanning Electronic Microscope (SEM),the related ultral corrosional features were identified as follows:a) Bore-hole with diameter around 10μm formed by fungi filament of lichen,b) Ultral etched pits on minor patched erosional pits,composed of networks of ultral furrows which 1.5-3μm wide.Under SEM,we observed the ultral features of the normal solution surface.The main characters are that:a) Ultral solutional pits are basically along the cleavage plane of calicite or fissure among calcite grains, b)There are still organisms and a few bioerosinal features,c) Calcite grain or micrite may loosen or even come off during the weathering (solution) processes.II.Discussion A. Micro-morphologic mechanism of natural damage The basi
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    THE CONFLUENCE AND DIVISION FLOWS IN RIVER CHANNEL
    Gao Jin
    1994, 49 (5):  430-439.  doi: 10.11821/xb199405005
    Abstract ( )   PDF (516KB) ( )   Save
    Alluvial river has a capability of automatic regulation.One problem which should be noticed is that the confluence and divison flows in river channel also have some effects of automatic regulation and follow the principle of the least resistance.In fact,the forming of the angles of the confluence and divison flows in river channel and the constitution of their width ratio (or their area ratio of cross section)for tributary and main current are all not random,they should ensure that the water and sediments in tributary and main currents can be drained freely.In this paper,a few problems are described.River mouth 1.When the water flow passes through the place where there are confluence and divison flowsin river channel an intersecting angle and their width ratio (or their area ratio of cross section) areformed,which correspond to the minimum value of head loss.Under turbulent flow the angle canbe worked out as follows:cosθ=(b1/b2)5(1+2(Q2/Q1))where the cross section of rive channel is supposed to be arc,the b1/b2is a specific value of riverwidth for tributary and main current.the Q2/Q1is a specific value of discharge for main current andtributary.when their water flow velocity is the same,we can get:cosθ=(b1/b2)5+2(b1/b2)3 When b1/b2=1/3 θ= 85°31’When b1/b2=1/5 θ=89°3’ So the angles of confluence and divison flows in general river channels are nearly right. 2.The calculated value is 62°23’ which is the angle of divison flow in the Shiyezhou branch ofthe Changjiang river and the real angle is approximately 60°.Both are nearly the same.3.At the place where there are confluence and divison flows in river channel,the functional relation between hydrodynamical essential factor and formal essential factor may be constituted andcan be expressed as follows: Q2/Q1=1/2[cosθ/((b1/b2)5)-1] or Q2/Q1=1/2[cosθ/((ω12)5)-1]Where is a specific value of the area of cross section for tributary and main currents.When the discharge ratio Q2/Q1changes,at the place with confluence and divison flows ,the intersecting angle and the width ratio(or their area ratio of cross section) for tributary and main currentsneed to be regulated.so that water flow may attain the condition of least resistance.4.The angle θ of confluence and divison flows in river channel are not greater than 90°.Becauseit can not meet the least resistance principle.5.Usually,the segment of river mouth is at a right angle or tend to be right with the line ofsea bank.River flows into the sea can be regarded as that the tributary with finite width (or finitearea of cross section) flows into the main current with infinite width (or infinite area of crosssection).The intersecting angles tend inevitably to be 90°.The characteristic of the strike of the segment of river mouth is also resulted from the fact that the water flow regulates constantly to attainthe condition of least resistance.
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    THE FORMATION AND GROWTH REGULARITIES OF SPATIAL TRANSPORT LINKAGE
    Zhang Wenchang, Jin Fengjun, Tang Xiufang
    1994, 49 (5):  440-448.  doi: 10.11821/xb199405006
    Abstract ( )   PDF (356KB) ( )   Save
    Spatial transport linkage which is defined as interregional traffic exchange by means of transport facilities is an important part of spatial interaction. It makes different parts of human being’s living space link each other, thus making up an interrelated structure and network by goods and passenger flow. Regional differentiation and interdependence are key reasons for transport linkage.The regularities of spatial transport linkage are composed of four sections formation regularities, growth regularities, distribution regularities, and exchange regularities. In this paper, formation and growth regularities are studied which are based on the domestic and foreign statistic data. The formation features of transport linkage can be summed up following 1) formation density of passenger is increased with economic development, but the density of goods is decreased. 2) The densities are very related with the structures and features of regional economy. 3) The area of region is also a factor for differentiaton of densities.The growth of transport linkage is closely related with the development of economy and industrial structure. Its regularities are featured as phasic. fluctuated, and correlative development.
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    TIDAL FLAT SEDIMENTS AND SEDIMENTATION ON THE CHANGXIN AND HENGSA ISLANDS AT THE MOUTH OF CHANGJIANG RIVER
    Yang Shilun, Xu Haigen
    1994, 49 (5):  449-456.  doi: 10.11821/xb199405007
    Abstract ( )   PDF (342KB) ( )   Save
    Based on the data of field observation and sediment samples. the paper deals with the grain parameters. the sedimentary structures and the formation processes. Meanwhile a basic model for tidal flat sedimentation on the alluvial islands in bifurcate river mouthes was established. Each profile has a general trend that sediments become finer landward though the details are different. Averagely,MZ(φ) increases from 3. 36 in the subtidal zone to 7. 03 in the supratidal zone. This trend is either due to the weakening of water energy of currents and waves or the appearance of the vegetation at the high Fart of the fla. Along the middle tidal line, the average MZ(φ) are respectively 3. 29, 4. 69,5. 79 and 6. 45 in the open east Hengsa coast, the bifurcate coast of west Changxin. the north and south branch coasts. δ= 0. 463.MZ-0. 785, r= 0. 94 (n=40), which is similar to the Chongming Island and the south coast of the Yangtze Estuary. 90% of the SK is positive that is different from beach sediment.there are apparent diversities among sedimentary structures on the east Hengsa coast. west Changxin coast and the north and south coasts although each profile shows the reduction of water energy from the low to the high places. The bare flat of the eastern Hengsa is dominated by thick sand bands in which flaser bedding and cross bedding sometime occur and the marsh is mainly alternate thick beds of sands and silts. In the west Changxin coast. flaser beddings and wavy beddings usually appear on the bare flat, alternate thick beds of fine sands and fine silts which are composed of alternate thin beds or wavy beddings occur in the Scirpus zone and horizofital laminers occur in the reed zone. In contrast. structures on the bare flats on the north and south coasts consisting of wavy beddings and alternate thin beds of silts and mudy silts and horizontal laminers of muds occur in the intertidal marshes and no beddings can be found in the supratidal marshes. This difference is also due to the variation of hydrodynamics.Abundant roots of plants in the marsh sediments often deform or destroy the layers. Sediments are slightly disturbed and shells are scarce because of the low biomass of benthic fauna and the unsteadyness of the flats.
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    A STUDY ON PROBABILITY DISTRIBUTION OF CRITICAL HYDROLOGIC DROUGHT DURATIONS USING THE METHODS OF ANALYTICS AND SIMULATION
    Feng Guozhang
    1994, 49 (5):  457-466.  doi: 10.11821/xb199405008
    Abstract ( )   PDF (340KB) ( )   Save
    Hydrologic drought is a common natural phenomenon. Its essential properties and pertinent indexes are important topics in drought study and hydrologic analysis and calculation, and also are important bases for planning and management of water resources system. In the view of the fact that the quantitative investigation to hydrologic drought is very limited in China, the definition of hydrologic drought is briefily described. From the viewpoint of hydrology. it is pointed out that hydrologic drought is a low flow process in which the stream flow is successively lower than a given truncation level in any averaging period such as a month, a season. a year. etc. The physical concepts of the main indexes. duration, severity and density. in a hydrologic drought. are explained. Also the basic concept of critical hydrologic drought duration is introduced.Properties of probability distribution of critical hydrologic drought durations in which the drought is characterized by a mean annual stream flow series with statistical independence are investigated. It is widely recognized that the most primary difficulty for quantitative investigation to hydrologic drought is the deficiency in measured data. Two methods are used in this study to solve the difficulty. One is the direct method. namely the analytic or statistic method. another is the indirect mothod, i. e. the experimental or simulative method. A probability density function of critical hydrologic drought durations characterized by the longest negative run lengths is transformed from a probability density function of the longest positive run lengths for an independently and identically distributed random variable series derived by Sen, using the enumeration method. Accordingly, a probability distribution function of critical hydrologic drought durations is also derived. A skewed (Pearson type three) one─order autoregressive model is used to simulate mean annual stream flow series based on both the characteristics of the stream flow in the study region and the experience in simulating practice.The region selected for this study is the Wei River basin. the largest tributary of the Yellow River. including two major tributaries of the Wei River. the Jing River and the North Luo River, and each of the three rivers has main station. A 60-years measured mean annual stream flow series for each station is used for the analysis. It is observed that the simulated flow series efficiently preserved the main statistic properties of the measured series. The results show a pretty goodaccordance among the probability densrties and distributions of critical hydrologic drought durations of the theoretical (analytic) model, and the simulated and measured data. In conventional or scientific hydrologic classification of drought and high flows, the mean or median of flow series is commonly regarded as a standard truncation level. However, it is not consistent with the design criterion of water supply projects and is lack of practical value. Therefore, for thepractical purposes, it is suggested that the flow corresponding to the design criterion of water supply projects should be a operational truncation level of hydrologic drought. It makes the drought have a meaning of" Water conservancy drought" . Because the design criterion has obvious regional properties, the classification criterion of hydrologic drought should reflect the regional properties. Therefore, the criterion can be regarded as a regionalized hydrologic drought index or parameter. Critical hydrologic drought duration is an important index in determining the drought protection period of a water supply project in the planning of water resources system. However, during a certain period, such as the economic life or safe service life of a project, the duration of critical hydrologic drought may be long or short but with different recurrent frequencies. If a relative long duration is used as the drought protection period. it may lead to a larger project scale and may be extravagant in funds due to the less recurrent opportunities. On the
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    A PARAMETERIZED ENERGY BALANCE MODEL OF GLACIER MELTING ON THE TIANSHAN MOUNTAIN
    Kang Ersi, Atsumu Ohmura
    1994, 49 (5):  467-476.  doi: 10.11821/xb199405009
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    Based on the measurement of energy balance on a glacier at the source area of the Urumqi River on the Tianshan Mountain druing the ablation seasons from June to August of 1986 and 1987, a parameterized energy balance model of glacier melting is developed with standard meteorological elements. Taking daily sunshine duration hours. daily mean air temperature. low cloud cover, wind velocity and vapour pressure at a standard meteorological station as the inputs to the model, the daily global radiation albedo, long-wave incoming and outgoing radiation, sensible and latent heat fluxes are simulated on the glacier, then the daily rediation balance. energy balance and melting heat of the glacier are obtained.In the parameterized heat flux expressions of the model, the extraatmospheric solar radiation is calculated by taking the slope influence into account. The ratio of daily global radiation to extraatmospheric solar radiation has a significant linear correlation to the ratio of daily sunshine duration hours to potential sunshine duration hours. The albedo of snow and ice decreases with the increase of air temperature, but the ratio of decrease of snow albedo is much larger than that of ice. The snow albedo is correlated to the power function of air temperature. while the ice albedo is linearly correlated to air temperature. Atmospheric emissivity is calculated with low cloud cover, while the surface emissivity of melting ice and snow is considered constant. According to the flux-gradient relationship, sensible and latent heat fluxes are approximated by the one level measurement of wind velocity, air temperature and vapour pressure.The simulated results indicate that during the summer months from June to August, most of net radiation is received by the glacier surface because of the relatively small albedo. In addition to the more sensible heat flux, the melting heat is then mostly distributed in the two months. Therefore, the intense melting period of glaciers on the Tianshan mountain is during July and August. At the height of 3910m a. s. 1. on Glacier No. 1 at the source of the Urumqi River, during June to August from 1986 to 1990, the incoming radiation is 224W/m2 which is global radiaton. While the outgoing radiaton consists mainly of reflected radiation (54%) and the surface effective radiation.(13%), and the remaining 33% belongs to net radiation. The incoming part in the energy balance consists mainly of net radiation, and sensible heat flux 13W/m2 which accounts for 15%. The incoming energy is consumed mostly by melting heat, accounting for 94%, and by evaporation latent heat.
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    ON THE DISCUSSION OF "CALCULATING THE CRITICAL DISCHARGE BY THE RELATION BETWEEN SEDIMENT DISCHARGE AND DISCHARGE"
    Yang Jiwu
    1994, 49 (5):  477-480.  doi: 10.11821/xb199405010
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    The Author thinks that it is discussible to calcaulate the critial discharge by using the relation,Qs=kQm, in two stations. where Qs is sedimemt discharge, Q is discharge, k is coefficient. and m is exponent.The reasons are 1) the values of m and k vary intensive, which have the relations with sediment concentration, slope, and morphology of the river, and the values of the above three vary in a large range also . 2) between two stations the discharges are not equal at the same time . 3) the calculated values of discharges will vary largely, when the values of m in two stations are similar.
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