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Table of Content

    20 September 1999, Volume 19 Issue 5 Previous Issue    Next Issue
    Wetlands and Global Environmental Change
    MENG Xian-min
    1999, 19 (5):  385-391.  doi: 10.13249/j.cnki.sgs.1999.05.385
    Abstract ( 244 )   PDF (905KB) ( 58 )   Save
    Wetland is one of ecosystems with important environmental functions and habitats for various biota on the earth. It is composed of hydrology, biogeochemical cycling and adaptation and improvement of biota for it. The interaction among those factors creates the entire function of wetlands. The role of wetlands in global environment is mainly found in the two aspects amongst health of wetlands themselves and function of wetlands in global environmental change. A wetland without being disturbed by unusual natural and human activities is in health statue since its diverse species, complex structure, function integration and stability of resisting disturbance. If disturbance is beyond the repairing ability of wetland environment, the health of wetland will be deteriorated, function of wetlands will be degenerated, consequently, will affect local and global environment. Wetland environmental change is sensitive to the responses of global environmental change and effect of global change to the wetland environment, especially human community activities on wetland. Global environment will inevitably affect wetland ecosystem and local environment, conversely, wetland ecosystem and local environment problem probably turn into global environment prblem.
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    On the Tendency, Problems and Countermeasures of the Sustainable Development in the Changjiang River Valley
    WANG He-sheng
    1999, 19 (5):  392-399.  doi: 10.13249/j.cnki.sgs.1999.05.392
    Abstract ( 146 )   PDF (892KB) ( 5 )   Save
    By studying the sustainable, fast and healthy economic development in the Changjiang River valley, harmonious development in the upper, middle and lower reaches, the adjustment of industrial structures and the implementation of favorable industrial policies, development of export-oriented economy, the development and rational layout of fundamental industries and infrastructures, harmonious development among cities of large, middle and small scales, urban and rural unification, rational exploritation and utilization of natural resources, the harnessing and protection of eco-environment, this paper analyzes the main tendency of sustainable development in the Changjiang River valley, the existing problems and the countermeasures.
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    Research on a GIS about the China’s Sealevel Changes in Quaternary
    WU Guo-ping, HUANG Yan, XIE Zhi-ren, WANG Wen, XU Ding-qing
    1999, 19 (5):  400-404.  doi: 10.13249/j.cnki.sgs.1999.05.400
    Abstract ( 95 )   PDF (650KB) ( 11 )   Save
    It is important to study sea level changes in theory and practice. With the rapid progress in remote sensing and computer technology, the development of GIS has been deepening and spreading. More and more practical GIS have been constructed. But little research has been conducted on how to use the technology of GIS which is a useful toolbox for the sea level changes. With the help of advanced GIS’s applied software ARC/INFO, and by using varied data, this report has build up a Sea level Change Geographical Information System and the application model of the sea level changes in Chinese shelf region in Quaternary since 18000 a B.P.. The application model not only resumes and demonstrates the ancient environment of Chinese shelf region in Quaternary but also supplies the fundamental data and analytical service of Chinese sea level changes. All results shall be resumed and demonstrated by using various compute output device.
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    Development of the Information-intensive Services and Their Impacts on the Urban Spatial Structure of Guangzhou, China
    YAN Xiao-pei
    1999, 19 (5):  405-410.  doi: 10.13249/j.cnki.sgs.1999.05.405
    Abstract ( 135 )   PDF (583KB) ( 17 )   Save
    This paper, based on the general survey data of the tertiary sector, focused on the development of the information intensive services and their impacts on the urban spatial structure of Guangzhou since the middle of 1980s. The development levels of information intensive services, including the general and internal levels, were initially analysed, which showed that the information intensive services of Guangzhou had higher development level than those of Guangdong Province and the whole country, and contributed greatly to the rapid development of the whole services. Then, the attention was turned to the analysis of the spatial development characteristics and reasons of information intensive services. Three characteristics were identified: the information intensive services had a multi cluster spatial pattern, there existed some dominant trades in the neighborhoods with relatively developed information intensive services, and the development centre of the information intensive services shifted obviously northwards. Many factors influenced the formation of the current spatial pattern of information intensive services, including historical, policy, economic, urban planning and construction factors and so on, but policy could be ranked the most important factor. Thirdly, the impacts of the development of information intensive services on the spatial structure of the city was examined. The results showed that the development of the information intensive services caused 1)the spatial replacement of urban function areas, 2)the upgrading and change of CBD functions and morphology, and the appearance of twin centre urban spatial structure, and 3)formation of the new growth core of the city with the development of technopole in Guangzhou. Finally a conclusion was drawn.
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    The Variations of Nitrogen and Phosphorus Concentrations in the Monitoring Stations of the Three Major Rivers in China
    DUAN Shui-wang, ZHANG Shen
    1999, 19 (5):  411-416.  doi: 10.13249/j.cnki.sgs.1999.05.411
    Abstract ( 133 )   PDF (1078KB) ( 30 )   Save
    The mean concentrations of nitrogen and phosphorus in the three major rivers of China during the 1980s in the monitoring stations were calculated according to the hydrological and water-quality data of the Luokou Station of the Yellow River, the Wuhan Station of the Yangtze River and the Gaoyao Station of the Pearl River from 1980 to 1989. Seasonal variations of nitrogen and phosphorus concentrations of the rivers are discussed,and their relationships with hydrological regimes are reported as well.
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    Evaluation and Analysis on Soil Quality Changes in the Sanjiang Plain
    HU Jin-ming, LIU Xing-tu
    1999, 19 (5):  417-421.  doi: 10.13249/j.cnki.sgs.1999.05.417
    Abstract ( 89 )   PDF (797KB) ( 6 )   Save
    Soil quality comprehensively reflects soil properties and is the most sensitive indicator mirroring dynamic changes of soil condition under the influences of human activities. It is very important for the prevention of soil degradation and the sustainable utilization of soil resources to research the changes of soil quality under the influences of the human activities. The Sanjiang Plain has been built into an important foodstuff base since large area reclamation in 1949. But due to lacking of environmental protection awareness and blindly pursuing economic benefit in the earlier reclamation processes, the soil environment of this area degrades, which will influence the sustainable development of agriculture. This paper establishes soil quality change evaluation model to calculate the soil quality matrixes of the top soils(cultivated layer soil)of the main cultivated soils in the Sanjiang Plain. The Changjing trend of soil quality after large area redamation in the Sanjiang Plain are quantitatively evaluated through analyzing the changes of soil quality indexes of the top soils of the main cultivated soils. Results show the quality indexes of the top soils of the main cultivated soils decrease after large area reclamation. Moreover, with the increment of the cultivation years the indexes decrease more. In the end, the forming reasons of this changing trends is simply discussed.
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    Basic Characteristics and Controlling Factors of Anastomosing Fluvial Systems
    WANG Sui-ji, LI Jing-song, YIN Shou-peng
    1999, 19 (5):  422-427.  doi: 10.13249/j.cnki.sgs.1999.05.422
    Abstract ( 172 )   PDF (814KB) ( 11 )   Save
    Anastomosing fluvial river is attached great importance by researcher only in resent years because anastomosed channel sandstone is a type of fine reservoirs of petroleum and natural gas and its flood plains and interchannel wetlands are fine places where coal is formed. The anastomosing river is typical in all sedimentary characteristics, geomorphology and hydrology, but the understanding on anastomosing fluvial systems is limited. In this paper some basic characteristics and controlling factors of anastomosing fluvial systems are summarized systematically.
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    A Discussion About the Changes of Radiation Balance and Surface Runoff in the Reservoir Area After the Three Gorge Project Being Built
    HONG Song, GE Lei, WU Sheng-jun, LI Xiao-yu
    1999, 19 (5):  428-431.  doi: 10.13249/j.cnki.sgs.1999.05.428
    Abstract ( 132 )   PDF (176KB) ( 3 )   Save
    This thesis started from equations of discharge and heat balance on earth surface, and discussed changes of the whole hydrothermal condition in the reservoir area after the Three Gorge Project being built through analysis of a series of variables. The preliminary estimates show that the surface radiation balance in the area along the reservoir will have a increase of 4.2%-6.7%, namely 8.0-12.6?103J/cm2·a, and the surface evaporation capality will also rise by 2.2%-3.9%,namely 12-21 mm/a. But the surface runoff in the reservoir area tend to descend about 8%-10%, mean 45-55 mm/a. In addition, the latent heat exchange and the turbulent heat exchange between earth surface and atmosphere will increase in different extents. The above mentioned conclusion has momentous significance to understand eco-environmental evolution in reservoir area.
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    Study on Classfication System of Middle Scale Landscape Ecology Mapping in the Sanjiang Plain
    LIU Hong-yu, LU Xian-guo
    1999, 19 (5):  432-436.  doi: 10.13249/j.cnki.sgs.1999.05.432
    Abstract ( 100 )   PDF (600KB) ( 39 )   Save
    A study on the classification of wetland landscape ecosystem is the key of landscape mapping. The fundamental rules of wetland landscape mapping classification system were studied first. The main factors which cause difference between landscape ecosystems were further detailed analyzed, and the conclusion is that the main factors are human activities, hydrology, geomorphology and vegetation. Finally, each category of the classification system is that: 1)the extent of human activities as the first class: natural wetland landscape, half natural wetland landscape and artificial wetland landscape; 2)geomorphology as the second class: flood land, depression, valley and terrace; 3)marsh wetland vegetation as the third class, which amalgamated with the way of indistinct assemble classification. Rivers as important wetlands were divided into two types: permanent river and marsh river. The classification system can give good service for landscape patterns, function, ecological planning and reconstruction of wetland in the Sanjiang Plain.
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    Study on Combination of Recreation Activities in Tourism Destination
    WU Cheng-zhao
    1999, 19 (5):  437-441.  doi: 10.13249/j.cnki.sgs.1999.05.437
    Abstract ( 149 )   PDF (789KB) ( 11 )   Save
    This paper tries to find out the methods and techniques about the integrated problem between the strategy of tourism development directed by market and planning of tourism resort from the aspect of recreation. The paper analyses the relations among recreation demands, recreation activities, facilities and their environment, and has the conclusions that a tourist resort consists of recreation activities, facilities, environment and their supporting system, the key of tourism resort planning is recreation planning. The combination of recreation activities has four types, and the general forms of their spatial layout have three models.
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    GIS Supporting Study on Current Siltation and Erosion Dynamic Changes of Yellow River Mouth
    ZHAO Geng-xing, ZHANG Wan-qing, LI Yu-huan, CHEN Le-zeng
    1999, 19 (5):  442-445.  doi: 10.13249/j.cnki.sgs.1999.05.442
    Abstract ( 107 )   PDF (182KB) ( 15 )   Save
    The dynamic change of siltation and erosion from May 1986 to October 1996 of the Yellow River mouth was studied supported by remote sensing and GIS. The results are as follows: 1. The current trend of the Yellow River mouth is that siltation tends to decrease and erosion tends to increase. Before January 1990 it increased by 24.9 km2 per year and it decreased by 2.40km2 per year after then. The northern and southwestern parts of the Yellow River mouth are main positions of erosion and the southern and mouth part are main positions of siltation. Also, the advancing rate of river mouth getting into the sea is decreasing obviously. 2. The area of the Yellow River mouth does not continuously increase as we studied before. Attention should be paid to the erosion of this region. 3. The reason of siltation decreasing and erosion increasing is the decreasing of water and sediment in the Yellow River, which caused by increasing use of the Yellow River water as well as the water and soil conservation in the upper reaches. In addition, the climatic change is one of the reasons, too.
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    A Preliminary Reflection on Several Theoretical Problems of Desertification
    ZHANG Hong, CI Long-jun, SUN Bao-ping
    1999, 19 (5):  446-450.  doi: 10.13249/j.cnki.sgs.1999.05.446
    Abstract ( 99 )   PDF (219KB) ( 3 )   Save
    The conception and connotation, assessment indicator system, mechanism of desertification occurrence, as well as the relationship between the land use/land cover change in desertification affected area and desertification were discussed tentatively. The definition of desertification in “United Nation Convention to Combat Desertification in Those Countries Experiencing Serious Drought and/or Desertification. Particularly in Africa”(hereinafter referred as CCD), from the author’s point of view, revealed the general intrinsic property of all types of desertification with different causes. The definition of desertification in CCD, therefor, represented the scientific connotation and was acknowledged worldwidely. The “Bench Mark" of assessment indicators, the climatic types and the areas in which the desertification occurred and the spatial scale of assessment should be taken into account when establishing the assessment indicator system of desertification. The mechanism of desertification occurrence is a core issue of desertification research. It involves the feedback courses and the nonequilibrium processes in desertification,as well as the relationship between the biodiversity,complexity and the stability of land ecosystem. Finally, the relations of land use/land cover change(LUCC)to desertification were discussed. It was pointed out that LUCC was one of the driving forces of desertification.
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    The Study of the Surface Emerging Ancient Channels on the South Coast Plain of Laizhou Bay
    HAN Mei, LI Dao-gao, ZHAO Ming-hua, JIANG Ai-xia
    1999, 19 (5):  451-456.  doi: 10.13249/j.cnki.sgs.1999.05.451
    Abstract ( 129 )   PDF (1380KB) ( 13 )   Save
    By the synthetical method, a systematic study of the surface-emerging ancient channels on the south coast plain of Laizhou Bay has been made. 25 surface-emerging ancient channels have been found and verified.According to the formed times, these ancient channels were divided into two stages: 6 palaeochannels formed in the Early and Middle Holocene, and 19 palaeochannels formed in the historical period. According to the landform features,the palaeochannels were divided into four types: upland palaeochannel belts,strip-shaped upland palaeochannels,trough-shaped depression palaeochannels, and ancient river beds. Among the four types, the strip-shaped upland palaeochannels are the main type.
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    Analysis on Development Stages of Coal Industry Cities
    GUO Shu-fen
    1999, 19 (5):  457-461.  doi: 10.13249/j.cnki.sgs.1999.05.457
    Abstract ( 127 )   PDF (717KB) ( 27 )   Save
    In the paper, the development of coal-industry cities is divided into four stages: initial exploitation; middle stable exploitation; last exploitation and coal resource exhaustion stages. And the characters of different stages discussed.
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    Artificial Neural Network Evaluation of Nutrient States of South Lake Water in Changchun
    LU Wen-xi, ZHU Ting-cheng
    1999, 19 (5):  462-465.  doi: 10.13249/j.cnki.sgs.1999.05.462
    Abstract ( 146 )   PDF (160KB) ( 21 )   Save
    Artificial neural network was developed to evaluate the nutrient states of South Lake water in Changchun in this paper. Taking Chemical Oxygen Demand, Tolal Nitrogen and Total Phosphorus as evaluation parameters and after repeating attempts, the four-layer structural Error Back Propagation network was established to evaluate lake nutrient states.There are three neural units in input layer, four in both hidden layers, and one in output layer. Taking the evaluation criterion of lake nutrient states as sample pattern, the network was trained in the light of learning rule of Error Back Propagation network. After 39?925 tries, the network reached the convergence standard given in advance. The operation process of the network is simple and convenient, and the results indicate that South Lake water in Changchun is, on the whole, in the state of extreme eutrophication.
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    Study of Extraction and Charting of Forest Resources Information
    ZANG Shu-ying, ZU Yuan-gang
    1999, 19 (5):  466-469.  doi: 10.13249/j.cnki.sgs.1999.05.466
    Abstract ( 70 )   PDF (193KB) ( 9 )   Save
    Information of forest resources is powerful impetus to improve the productive forces and economic development of forestry, also is the key to realize forestry sustainable development. Extraction and charting of forest resources information depends on effective process to enormous spatial data. Geographic Information System(GIS)consists of a database containing spatially referenced land related data, as well as the procedures and techniques for systematically capturing, storing, retrieving, analyzing, processing, updating, and displaying those data. GIS enables the user to manage geographic data more efficiently and enhances the decision-making process for planning purposes. It has become increasingly important for spatial analysis of forest resources and forest sustainable management. The theme made inquiries about the technique of ARC/INFO 7.0.1 and ARCVIEW 3.0 in the extraction and charting of forest resources information. And taking Tayuan Forest Farm in Daxinganing Forestry Area as an example, makes a concrete exposition for the application of the new methods.
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    Study on Geophysical Survy Mothods Used in Soil Improvement
    GUO Xiu-jun, ZHANG Guang-xin, TAN Xiao-ping
    1999, 19 (5):  470-474.  doi: 10.13249/j.cnki.sgs.1999.05.470
    Abstract ( 73 )   PDF (723KB) ( 17 )   Save
    How to master the distribution of soil, especially the distribution of saline-alkali soil and the saline-alkali degree in the whole transformation area before exploration, how to test the result of transformation effectively are the problems that must be faced during the exploitation. This paper discusses the theory and process which resolve those problems with the methods of geophysics, and proves that those methods are feasible and effective. In order to make scientific and technical researches between different subjects, all those methods will be used in the national key programs of the Ninth Five-Year Plan: comprehensive management of saline-alkali land and agricultural sustainable development in the Songnen Plain.
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    Mechanical Analysis of a Single Saltating Particle in Air Flow
    YANG Bao, ZOU Xue-yong, WANG Zhou-long, DONG Guang-rong, LIU Yu-zhang
    1999, 19 (5):  475-478.  doi: 10.13249/j.cnki.sgs.1999.05.475
    Abstract ( 39 )   PDF (606KB) ( 7 )   Save
    Mechanical analysis of a single saltating particle in air flow and its motion mechanism play an important role in development the Physics of Wind blown Sand. By means of high speed multi flash photography, this paper analyzes the variation law of drag coefficient and lift coefficient of saltation particle, and makes a comparison between drag, lift force and gravity force. Conclusions are as follows. First, drag coefficient of sand particle is different from one of idealistic small sphere. Second, among all forces, drag whose values can reach several times of gravity force is the most important, gravity force lists second, and lift force which accounts for more than 20% is not negligible. Third, using numerical method, saltating trajectory of sand particle has been obtained. Comparison of computed trajectory and measured trajectory shows that mechanical analysis discussed forward is very reasonable. Last but not least, sand particle may be subject to other forces similar to Magnus or Saffman lift forces.
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