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    1991年, 第1卷, 第1期 刊出日期:1991-03-20    下一期
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    论文
    SEDIMENT DISCHARGE OF THE HUANGHE RIVER AND ITS EFFECT ON SEDIMENTATION OF THE BOHAI SEA AND THE YELLOW SEA
    任美锷, 史运良
    1991 (1):  1-18. 
    摘要 ( 696 )   PDF(1327KB) ( 760 )  

    The Huanghe (Yellow) River, with annual sediment discharge about 11×108tons, contributes about 17% of the fluvial sediment discharge of world's 21 major rivers to the ocean because its middle reaches flow across the great Loess Plateau of China. Sediment discharge of the Huanghe River has a widespread and profound effect on sedimentation of the sea. The remarkable shift of its outlet in 1128-1855 A.D. to the South Yellow Sea formed a large subaqueous delta and provided the substrate for an extensive submarine ridge field.The shift of its outlet in the modern delta every 10 years is the main reason why with an extremely heavy sediment input and a micro- tidal environment, the Huanghe River has not succeeded in building a birdfoot delta like the Mississippi. The Huanghe River has consistently brought heavy sediment input to sea at least since 0.7 myr.B.P. Paleochannels, paleosols, cheniers and fossils on the sea bottom indicate that the Yellow Sea was exposed during the late Quaternary glacial low-sea level and the Huanghe River had crossed the continental shelf, discharging its sediment to the Okinawa Trough in about 25,000-15,000 yr.B.P.

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    AN APPROACH TO RETAIL COMMERCE LOCATION OF GUANGZHOU URBAN AREA
    吴郁文, 谢彬, 骆慈广, 张蕴坚
    1991 (1):  19-29. 
    摘要 ( 721 )   PDF(631KB) ( 853 )  

    Proceeding from the commercial function of Guangzhou urban area, this paper expounds the principles and requirements for choosing commercial location, puts forward the bases to determine the limits of commercial centres. Thirty major commercial centres, in Guangzhou urban area are classified by means of cluster analysis. The function, size, hierarchy and interconnection of commercial centres of different groups are studied. The paper emphatically analyzes the major characteristics and formation factors of the commercial location of Guangzhou urban area. Finally, to counter some problems in existence, some suggestions are put forward in order to improve the commercial location of Guangzhou urban area.

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    THE POSSIBILITIES AND REALITIES ON THE REMANAGEMENT OF DESERTIFIED LANDS IN THE TRANSITIONAL ZONE BETWEEN THE DRY-FARMING AREA AND THE GRAZING AREA IN NORTH CHINA
    朱震达, 刘恕, 杨有林
    1991 (1):  30-41. 
    摘要 ( 927 )   PDF(710KB) ( 723 )  

    The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified and 47.4% are the lands where desertification is under way. They are caused by over-reclamation for farming, over-grazing, unreasonable collection of firewood, the destruction of vegetation and the misuse of water resources. Under the ecological environment in semi-arid zone, the degraded environment process possesses the ability of restoring to its original status as soon as the interruption of excessive human activities are eliminated. The fencing- and-self-cultivating method is an effective measure adopted universally in semi-arid zone to cure the desertified lands.The desertified lands can be readjusted and controlled easily if other controlling measures are supplemented. The fundamental ways to control desertification are to utilize rationally the resources, to readjust the existing land use pattern in the transitional zone between the dry-farming area and the grazing area, and to adopt a series of measures that are suitable to local conditions.It is found that the desertified lands in the zone are characterized by the possibilities to readjust, and also that the successful reverse readjustment is becoming a reality in many typical regions.

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    ON THE RELATION BETWEEN THE EVOLUTION OF NATURAL ENVIRONMENT AND HUMAN FACTORS AND THE DEVELOPMENT OF URBAN SETTLEMENT——Take the Lanzhou Valley Basin as An Examples
    鲜肖威, 张林源, 艾南山, Wihelm Wohlke
    1991 (1):  42-53. 
    摘要 ( 631 )   PDF(717KB) ( 664 )  

    Lanzhou Valley Basin is composed of two smaller diamond-shaped basins striking from NW to SE and including 6 river terraces. The lower terraces remaining even and smooth are main sites for city buildings. The main function of Lanzhou urban settlement is a ferry and transport centre. Lanzhou used to be an im-portant crossing site and post on the "silk road", and then became a transport and trade centre in Northwest China. In the middle part of the 17th century, Lanzhou became the capital of Gansu, a new province. The development process of Lanzhou urban settlement indicates that urban settlement is a system consisting of natural environment and human society based on the former.

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    THE ECOLOGICAL FEATURES AND ECOLOGICAL CONSTRUCTIONS OF A MIRE IN CHINA
    黄锡畴
    1991 (1):  54-61. 
    摘要 ( 695 )   PDF(465KB) ( 831 )  

    A mire as an ecosystem, usually is considered as an aquatic ecosystem, or a terrestrial ecosystem. The author thinks that mire is a special ecosystem between these two ecosystems, and proposes the new concept that a mire is a natural ecosystem with transitional nature of semi-water and semi-land formed by water and land interaction. The paper discusses the nature of the mire ecosystem, the exploitation and utilization and ecological construction of a mire.

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    TREND SURFACE ANALYSIS OF THE EXISTENT SNOWLINE IN WEST CHINA
    蒋忠信
    1991 (1):  62-69. 
    摘要 ( 849 )   PDF(430KB) ( 724 )  

    The analysis of twenty five existent snowline elevation values in West China indicates that snowline elevationH (meter) presents zonality change declining from south to north with latitude φ(degree) and the change declining from west to east with longitude which relates to the distance L (kilometer) to the east coastline. Therefore, the first order trend surface equation of the snowline in West China shows a plane incline from southwest to northeast. The second order trend surface equation of the snowline in West China truly represents the distribution law of the snowline in West China. Its form resembles a "overturned anticline" from southwest to northeast. The "raised axis" seems to be superimposed upon the first order trend surface.It reflects the effect of the relief. The snowline elevation in West China depends on horizontal zonality, distribution of ocean and land, and the relief.

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    SOME PROBLEMS ON REGIONAL DEVELOPMENT IN XIAMEN CITY
    姚士谋, 赵锐, 徐桂卿, 张立生
    1991 (1):  70-82. 
    摘要 ( 715 )   PDF(782KB) ( 883 )  

    Xiamen is an important coastal harbour and tourist city. Since the establishment of the Xiamen Special Economic Zone in 1980, great changes of developments in economy and urban construction have taken place. The comprehensive development is most important to Xiamen's future. Xiamen has favorable geographical location, high level of economy opening to the outside world and close relation with Xiamen-Zhangzhou-Guanzhou economic area. The Xiamen Special Economic Zone should play the role of central city in the south Fujian Province.

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    SALT LAKES ON THE INNER MONGOLIAN PLATEAU OF CHINA
    郑喜玉
    1991 (1):  83-94. 
    摘要 ( 591 )   PDF(678KB) ( 844 )  

    Salt lakes, the main source of trona resources in China, are widely distributed on the Inner Mongolian Plateau. Their characteristics are large in number, various in type, and short in salt-forming stage, especially their considerable number is well-known at home and abroad. The paper discusses the physical constituents, hydrochemical features, classification, formation, evolution, and salt-forming regularities of salt lakes through analyzing their distribution, lacustrine deposits and salt-forming conditions.

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