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  • 1997 Volume 52 Issue 4
    Published: 15 July 1997
      

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  • Zhou Yixing, Meng Yanchun
    1997, 52(4): 289-299. https://doi.org/10.11821/xb199704001
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    Since 1980’s, suburbanization has been beginning in China. Research on suburbanization has been done lots in the western countries, whereas its research is just begun in our country now. In order to explore its benefits and avoid its ill side effects on urban development, it is urgent to work hard on the essence, mechanism and law of suburbanization, and to compare the difference between China and the western countries. Therefore, the article makes the research on Shenyang’s suburbanization. It is composed of the following parts: 1. Defining division concept on urban central area, inner suburb, and outer suburb. 2. Testifying the beginning of suburbanization since 1980’s and its intensity by checking the data of the third and forth census. 3. Describing 1990’s suburbanization by positivism study on two samples. 4. Analysing the suburbanization mechanism, specially emphasizing the system of land paid use. 5. Giving suburbanization comparison between China and the western countries. 6. Suggesting some policies of adjustment and controlment on suburbanization in view of existing situation.
  • Wei Chaoyang, Zhang Licheng, He Shujin, Zhao Guijiu
    1997, 52(4): 300-307. https://doi.org/10.11821/xb199704002
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    Based on some reported statistical data, this paper summarizes the general conditions of the eco-environment in coal mining areas in China. The general characteristics of the eco environment in coal mining areas in China are also concluded. It is pointed out that there exist three kinds of antinomies on this issue: 1) region with large extent of coal exploitation owning large population but little cultivated land in northern China; 2) region rich in coal resources but with fragile ecosystem in northwestern China; 3) dispersion of coal exploitation with heavy pollution in the broad southern China. The major existing problems on the management of the eco environment in the coal mining areas in China are as follows: 1) irrational distribution of mining areas and absence of rational eco environmental planning; 2) inperfections in policy and law; 3) passive and unitary conditions in the management of eco environment; 4) uncontrollable expolitation of the small coalpits; 5) deficiency in research, which results in the blindness in the management. 5 strategies are put forward on the comprehensive management of the eco environment in coal mining areas in China: 1) adjusting the industrial structure in order to strengthen the economy of mining areas and ensure ecological management and restoration with economical development; 2) setting up experimentations and demonstrations in various regions in China; 3) carrying out land reclamation and waste utilization; 4) extending clean coal technology; 5) accelerating the establishing speed of environmental policies and laws.
  • Chen Zhiqing
    1997, 52(4): 308-315. https://doi.org/10.11821/xb199704003
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    This paper analyzes grain size characteristics based on samples of flood plain substance composition collected systematically from Longmen Sanmenxia section of the Yellow River. In terms of spatial changes, the longitudinal distribution of alongshore flood plain substances is characterized by coarseness at upstreams and fineness at downstreams. In terms of horizontal changes, grain size of flood plain substances changes from coarse at forward fringe to fine at backward fringe. Comparisons of grain size graduation of flood plain substances with that of river bed substances indicated that substances of flood plain facies are finer than that of river bed facies. They differ distinctively from each other. Comparisons of flood plain substances with suspended particles showed that sediments deposited on flood plains are mainly the portion of coarser particles in incoming suspended load from upstreams. The paper also studies the impact of flood plain width and substance composition on river bed geometric morphologies. It is found out that river bed width depth ratio is very closely related with flood plain width as well as percentage of silt and clay content in flood plain substances. The results of the above studies indicated that the first important condition accountable for Yellow River wandering is intense channel accumulation, and then a broad flood plain wider enough to satisfy the great amplitude in wandering. In case finer particles in flood plain substances is low in concentraction with weak anti scouring capability, the river channel will become even shallower and wider, so aggravating the extent of wandering.
  • Xie Ping, Liang Ruiju
    1997, 52(4): 316-323. https://doi.org/10.11821/xb199704004
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    According to a general theory of conceptual watershed geomorphy concentration model, using the conceptual element of diffusion analogy reach to simulate the concentration action of each ordering unit channel, this paper developes a diffusion analogy type watershed geomorphy concentration model in which the parameters are flood wave velocity and diffusion coefficient. The instantaneous unit hydrograph (iuh) of three order basin is derived, and the nature of the iuh is analysied. The author discusses the methods of moment and interior penalty functon (ipf) which are used to obtain the parameters of the proposed model. The model is tested in Nanyan catchment and the result shows that the model has a rational structure and an accuracy when the ipf method is used.
  • Feng Ping, Feng Yan
    1997, 52(4): 324-330. https://doi.org/10.11821/xb199704005
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    The application of fractal theory has been largely developed since it was used in geography and hydrology in 1980’s. In this paper, the fractal dimensions of stream length and river network are investigated by two methods of box counting and stream order law, and the fractal features of some main rivers in the Haihe River basin are practically estimated. The following conclusions were obtained through analysis. (1) It is feasible to study the fractal dimension of river morphology by two methods of box counting and stream order law. The accuracy of box counting is higher because the method uses the basic definition of fractal dimentsion, but its calculating work is very large, especailly for the fractal dimension of river network. The method of Horton’s stream order law can also provide the fractal imension by river system parameters. This indirctly shows that horton’s stream order law can reprent some basic characteristics of rivers. (2) The value of fractal dimension can be used as the index of river morphology becuase stream length and river network have the obvious fractal feature. The fractal dimension shows the complex of river morphology, and has the property of scale invariant. Therefore, the problem of calculation river morphology under different ratio scale can be resolved by the fractal dimension, and it is helpful to understand the evolution process of river morphology. (3) The fractal dimensions of stream length in Haihe River baisn vary from 1.01 to 1.14, and its mean value is 1.10. The fractal dimensions of Lanhe River and Daqing River are larger because their stream channels are zigzag. On the constrary, the fractal dimension of Rongding River is the smallest for its smooth stream channel. The fractal dimensions of river network vary from 1.50 to 1.69, and that of Zhiya River is the largest because it has many branch rivers. The mean fractal dimension of Haihe River system is 1.57, and this value accords with La Barbera and Rossos’s (1989) statistical data that the fractal dimensions of river network are from 1.6 to 1.7. This result shows that Haihe River system is roughly a standard river basin.
  • Liu Gengnian, Cui Zhijiu, Ge Daokai, Wu Yongqiu
    1997, 52(4): 331-338. https://doi.org/10.11821/xb199704006
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    The stratified slope deposits (gr zes lit es) locate on the east or southeast ward slope base and distribute 4 100 m above sea level at Xiaonanchuan of Kunlunshan Pass. The typical profile is near 5y Daoban by the Qinghai Tibet Highway at Xiaonanchan, with a total thickness of 27m. The profile is composed of three layers, the base layer is of residue with a thickness of 2m~3m, the middle layer is of stralified slope deposits with a thickness of 10m~15m, and the top layer is of loess with a thickness of 9m. According to the grain size and sedimentary structures, the middle stratified slope deposits can be divided into two parts, the lower part is greater in grain size and thicker in bedding, and is evolved from gelifluction, the upper part is smaller in grain size and thinner in bedding with an average bet thickness of 0.4cm. The fragments of the upper part show a prolonged and repeated frost action, and the bedding shows that the deposit is formed by sheet wash that is supplyed by perennial show patch on the upper slope. The stratified slope deposits began at 60000aBP and ended at 44000aBP. The loess on top layer was formed in a cold dry climate at 38000aBP. Analysis data of sedimentary structures, grain size, chemical composition, scanning electron microscope and dating show that the stratified slope deposits were formed in the early period of Last Glaciation ( 60000aBP~44000aBP), with a climate change from cold wet tl cold dry. The loess on the stratified slope deposits reflects a remarkable cold dry condition in the Last Glaciation and Holocene. In general, this profile shows projectively a cold wet climate instead of a cold dry climate in the early period of Last Glaciation in the area of Kunlunshan Pass. This does not fit with the monsoon model, therfore, it is believed that this area was influenced by the westerlies in the early Last Glaciation.
  • Lu Jinfa, Cui Shuhong, Lin Li, Huang Xiuhua
    1997, 52(4): 339-344. https://doi.org/10.11821/xb199704007
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    According to the definition of land degradation/desertification by UN, vegetation coverage, erosional morphology and surface material were chosen as the criteria for asseessing land degradation in this paper.Based on this, assessment, mapping and comparison of land degradation between 1950’s and 1980’s were carried out by the interpretation of aerial photos of the two periods and by using a Fuzzy model. It was shown that the degraded land caused by water action accounts for 36% of the total studied area, in which severely and very severely degraded land, with the characteristics of bare badland, occupied 5% of it. Moreover, obvious downslope zonation and spatial variation of land degradation were observed in the studied area. It was proved that the severely and very severely degraded land existed even before the foundation of the country and could be traced back to the Ming and Qing Dynasties at least. Development of land degradation manifested itself as drastic reduction of non degraded land and relevant increase of slightly and moderately degraded land from 1950’s to 1980’s.
  • Zhang Zhaogan, Yang Jianming, Wang Xiang, Shen Ping
    1997, 52(4): 345-352. https://doi.org/10.11821/xb199704008
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    A further karstlogical research including morphology, hydrogeology, hydrology and pulse test is done in an experimental area the Houzhai underground river basin, Puding county, Guizhou Province. Eight types of spatial structures are obtained by cluster analysis. These are Fenglin basin, Fenglin clay platform, revived, Fenglin doline depression, oldfenglin doling depression, Fenglin (or fengcony) valley and Fenglin depression. They have their own surface and underground structral features, so their characteristics of morphology, hydrogeology, hydrological process, hydrochemistry and pulse waves are different. By analysing these characteristics on the basis of observations it can be seen that different hydrology process curves and the respons curves of puls test may reflect distinct underground structral features. Further, it is believed that the Karst landform evolution in the basin is mainly a positive evolutionary process from Fenglin doline to Fenglin basin accoding to the study on the spatial structure. But reverse evolutionary process from fenglin basin to Fenglin doline has been formed in the western region.
  • Li Chunchu
    1997, 52(4): 353-360. https://doi.org/10.11821/xb199704009
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    1. The estuary can generally be divided into three sections. (1) Near mouth section: Its upper boundary is the tidal influence limit in the flood season, and the lower boundary is the limit between fresh water and brackish water (with salinity 0 1‰) in the dry season. This section is controlled by the fresh water and not influenced by diluted water (or mixed water) going upstream, which represents the runoff predominance. (2) River mouth section: Its upper boundary is the limit between the fresh water and brakish water in the dry season, and the lower boundary is at the place where there is the salt water with salinity about 30‰ in the bottom layer during flood season. It is the intruding front of the salt water (or continental water) during flood season where exists mixing and interaction of salt and fresh waters, with reciprocal tidal current. (3) Mouth outside seashore: Its bottom layer is controlled by salt water or continental water, and surface layer is covered by the diluted water (or mixed water), where the movement of tidal current is characterized by the rotation. 2. Accoding to the relative intensity of the influences of the river, tide or wave, the estuaries can be divided into three basic classes: river dominated, tide dominated and wave dominated. Their chief characteristics of dynamics, sedmentations and geomorphologies are also discussed in this paper. 3. The function of estuarine system can possibly be accommodated and satisfied by the input, transfer and output of informations and energies from river and sea, which is activated by continuous adjustment of the system′s elements, such as density ( ρ ), depth of the limit of salt and fresh water ( h′ ), velocity ( U ), slope of water surface ( J ), water depth ( H ), width ( B ) and sediment composition ( D ), and a specific optimized form of the estuary is established. The automatic adjustment of estuary is subordinated to the general rules in the alluvial river processes, including: (1) having balance tendency; (2) making initial energy of the system tend to redistribute in some rules; (3) integrating the adjustment processes, that is, the element of the system are influenced with each other and response as a whole; (4) having feedback of automat. For satisfying a transformation from river to sea or from sea to river, the estuary should modulate and transform by mixing salt and fresh water. However, because different estuarine types have their own predominant dynamic conditions, the estuarine system should draw supports from other regimes to do the automatic adjustment in order to maintain the balance. The characteristics of automatic adjustment for the three classes of estuaries are discussed in this paper.
  • Zhang Xianzhou, Zhang Yiguang, Zhou Yunhua
    1997, 52(4): 361-365. https://doi.org/10.11821/xb199704010
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    Based on the measured data of spectral radiation on Qinghai Xizang Plateau from April to October, 1994, ratio of photosynthetically active radiation ( PAR ) to global radiation was presented, i.e. η =0.439±0.009, and 1J energy of PAR is equivalent to 4.43 μmol quantum. In the climatological estimation of Qinghai Xizang Plateau, following equations can be used to estimate the averages for every ten days of daily total PAR energy HPAR(MJ·m-2d-1)and daily total quantum UPAR(mol·m-2d-1):HPAR=(0.399+0.036lgE*)·H UPAR=(1.768+0.159lgE*)·H H(MJ·m-2d-1) is the average daily global radiation for ten days. E*=E·P0/P,P0(hpa) is the standard atmospheric pressure, P (hpa) is the atmospheric pressure at the spot, E (hpa) is the water vapor pressure on the ground.
  • Liu Changming
    1997, 52(4): 366-373. https://doi.org/10.11821/xb199704011
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    The descriptions of this paper is based on field experimental research of water transfer mechanism in soil plant atmosphere continuum (SPAC), which was involved in a key project under the title of “Scientific Base of Applied Research on Water saving Agriculture in the North China Plain” supported by National Natural Science Foundation of China (NNSFC). Water movement in soil plant atmosphere regarding hydrological cycle includes the interactions between surface water, groundwater, soil water, plant water and atmospheric water. Some detailed experimentats have conducted in recent years.These issues include following four parts: (1) simulation of soil water movement and calculation of soil water by using large sized lysimeters; (2) studies on field evapotranspiration regulations under water saving conditions; (3) the interface processes of water fluxes and water saving regulation in SPAC; (4) development of integrated model of water movement in SPAC. Three representative experimental stations of CAS at Luancheng (Hebei province), Nanpi (Hebei Province) and Yucheng (Shandong Province) with different conditions of buried groundwater tables 26, 6 and 2 m, respectively were selected to conduct the experiments and observations on water and energy processes of groundwater, soil, crop and atmosphere system, which carefully scheduled to observe at same time. Several interface processes of water fluxed in SPAC including interfaces between soil and root, plant and atmosphere, soil and atmosphere, soil water and groundwater with different physiological and ecological conditions involved in this study. Finally the author draws brief remarks as follows: field water systems consist of several links of hydrological states being of complexity, and the preliminary outcomes of this study illustrated the applicability in water saving agriculture. The development of interface hydrology study could be very helpful to better understanding of hydrological cycle mechanism. This would create a new aspect of hydrological science.
  • Ding Jing, Yuan Peng, Yang Rongfu, Deng Yuren
    1997, 52(4): 374-381. https://doi.org/10.11821/xb199704012
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    A drought is recognized as natural phenomenon which is characterized by the fact that demanded water quantity surpasses natural supply. However, on its definitions and quantitative indices there is no general agreement. In order to examine the drought properties of the main rivers in china, negative run lengths (NRL) is chosen as an index indicating the quantitative degree of a drought. In this paper NRL is defined by persistent duration of annual runoff related to negative deviation from mean annual runoff. The choice of NRL is due to its clear concept, convenient computation and ability in comparison. Based on a large number of observed data on the main rivers in China, the statistical properties of NRL such as distribution, mean value, and maximum value have been exmined in this paper. The distribution type of NRL is explored and identified by using a station year method. The final results obtained in this paper can be summarized as follows: 1. Pearson Type Ⅲ distribution may be used to describe the statistical properties of NRL on the main rivers in China; 2. Mean NRL has a close relation to first order autoregressive coefficient of annual runoff; 3. Maximum NRL within a period can be taken as a measure of drought severity. Its occurrence probability may be reasonably estimated by using a stochastic generation approach. Two case studies are given for two hydologic stations: Harbin and Shanxian.