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Table of Content

    24 December 2001, Volume 20 Issue 4 Previous Issue    Next Issue
    Original Articles
    The Progress on Comprehensive Land Sciences focused on Land-use and Land-cover change
    ZHANG Ming
    2001, 20 (4):  297-304.  doi: 10.11820/dlkxjz.2001.04.001
    Abstract ( 576 )   PDF (925KB) ( 1197 )   Save
    Land use and land cover change has become the core region of land sciences, earth systematic sciences, global environmental change and sustainable development. The fundamental objective of such research is to realize the effective management and sustainable use of land resource. They are not only the fundamental basis to solve the problem of resource and environment, but also the essential predomination for the economic growth and the process of regional sustainable development. Taking major related research plans and projects both in China and abroad in recent years for reference, this paper summarized the up to date international progress of several regions in the land science, such as land use and land cover change, systematic analysis and evaluation of land resources, land quality indicators system, impacts on ecological environment and the sustainable land use.
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    The Theoretical Basis and Progress: Utility and Protection of the Farmer-land in Foreign and Home
    LI Xian wen, Lin Pei
    2001, 20 (4):  305-312.  doi: 10.11820/dlkxjz.2001.04.002
    Abstract ( 465 )   PDF (198KB) ( 762 )   Save
    This article reviews the theories and progress of farmer land utility and protection, and analyzes the scientific basis and developing process of farmer land protection. This article pointed out that land productivity study is the scientific basis to ascertain the amount of the protected farmer land, that land evaluation and assessment is the basis of farmer land protection planning, and that the land plan and regulations is the shield of practice of farmer land protection. At the same time, this article further analyzes several theoretical and practical problems with farmer land use and protection in China, and some suggestions are given based on the practices of farmer land protection in foreign countries.
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    Land Sustainable Use and Optimize of the Yellow River Delta
    HE Shu jin, LI Xiu bin, ZHU Hui yi, SU Guang quan
    2001, 20 (4):  313-323.  doi: 10.11820/dlkxjz.2001.04.003
    Abstract ( 388 )   PDF (1061KB) ( 564 )   Save
    The current status of land use in Dongying city, a major part of the Yellow River Delta, is dominated in terms of land types by farmland, water surface and unused land and its land use changes in the last 50 years are mainly reflected in a undulating trend of farmland area, the adjustment of agricultural structure and increase in non farmland area prevailed in the process of land use type transformation, and close relationship between farmland change with population and economic development. The sustainable land use of the region should follow the optimized principle and objective of adopting measures suitable for local conditions, bringing into full play superiorities, emphasizing synthetic benefits and protecting eco environment. Constrained analyses of sustainable land use are conducted concerning land use types including land suitability grades, cultivated area, land for forestry, land for animal husbandry, land devoting to settlements, industry and mining, land for transportation, water surface and unused land. Based upon which optimization structure and allocation schemes related to sustainable land use are raised such as returning grain plots to forest and grassland, increasing forest coverage, properly concentrating rural settlement locations, strengthening land consolidation, rationally reclaiming marshland, wasteland, grassland, saline alkali land.
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    The Analysis on Spatial Feature of Land Use under the Defferent Background of Eco-Environment Based on GIS
    WANG Si yuan, ZHANG Zeng xiang, ZHAO Xiao li, LIU Bin, ZHOU Quan bin
    2001, 20 (4):  324-330.  doi: 10.11820/dlkxjz.2001.04.004
    Abstract ( 393 )   PDF (783KB) ( 583 )   Save
    The research of spatial temporal features of land use and land cover is significantly important for better understanding of land use/land cover change and environmental management for sustainable development. In order to study the spatial temporal changes of land use and land cover, researchers use the technologies of Remote Sensing and Geographical Information System to analyze the spatial distribution of spatial temporal feature of land use and land cover under the different temperature, different rainfall, and different elevation. It is shown that the maximum of percentage of land distributes in cold temperate zone, in drought zone with the rainfall is less than 250mm, and in region with the altitude between 1 000 meter and 3 500 meter. Above all, the maximum of percentage of plantation distributes in temperate zone with the rainfall between 400 mm and 800 mm and the altitude between 1 000 m and 3 500 m; The meadow distributes mostly in cold temperate zone with the rainfall is less than 250 mm and the altitude between 1 000 m and 3 500 m; The build land distributes mostly in warm temperate zone with the rainfall between 400 mm and 800 mm and the altitude between 0 and 100 m; The maximum of percentage of un use land distributes in cold temperate zone with the rainfall is less than 250 mm and the altitude between 1 000 m and 3 500 m.
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    The Complexity Analysis of the Spatial Structure in Shanghai
    WANG Zheng, DENG Yue, SONG Xiu kun, WU Bing
    2001, 20 (4):  331-340.  doi: 10.11820/dlkxjz.2001.04.005
    Abstract ( 783 )   PDF (944KB) ( 1678 )   Save
    In this paper we make a research on complexity of the spatial structure of Shanghai. It is found that the spatial structure of Shanghai not only shows the typical Burgess structure and Lo sch sector but also shows a sign of complexity. The evidences are as following: Firstly, the commercial cg (center of gravity) and the central business center (CBD) of Shanghai are separated. The CBD of Shanghai is quiet stable because the existence of industrial inertia. But the commercial cg always moves after the population cg to pursue maximal profit. The interaction of the commercial cg and the CBD may cause a sudden transition of the CBD. This phenomenon is the mutation in Chaos theory. Secondly, the industrial zones may not always be of united Burgess Structure. Different period may produce different Burgess rings because of different technique. In 1950’s and 1960’s there’s only one peak in Shanghai which stands for the agglomeration of industry. It is near the central business center. And in 1970’s and 1980’s another peak appeared in the area 7~8 kilometers away from center. After 1990 the third peak came out further away from the CBD. There are stable low density industrial areas between the first peak and the second peak from the center. So the industrial zones appear alternatively in spatial. As to the case of Shanghai, it is showed as an industry oriented multiple structure. Thirdly, edge cities will appear after the central city overcomes the potential threshold. Edge cities appear in a hierachical way, and look like flying spots in spatial. It is seemed that in Shanghai the edge cities are controlled by the round force and sector tension simultaneously. The scales of the edge cities are controlled by the spatial distance between the center of Shanghai and edge cities. But the control power shows no linear character. If the edge cities are too near to the center, they are of course more likely to accept the leakage from the center, but it also raise the rent of edge cities. So the scale of these edge cities will be neither too large nor too small. As the distance becomes longer, edge cities will be sparse. But as the rental comes down the scale of the edge cities are larger although the number of them are small. In general, the spatial distribution of the edge cities in Shanghai shows the evidences of chaos.
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    The Study of Distribution of N, P and heavy metals in Guanting Reservoir and Yongdinghe River
    LIANG Tao, ZHANG Xiu mei, ZHANG Shen
    2001, 20 (4):  341-346.  doi: 10.11820/dlkxjz.2001.04.006
    Abstract ( 411 )   PDF (250KB) ( 518 )   Save
    samples in water were collected in Guanting Reservoir and Yongdinghe River during low water period (winter and spring). Contents of N, P and heavy metals in original and filtering water were analyzed. Various species of N were also determined. Contents and spatial distribution of N, P and heavy metals were discussed. The results show that heavy metals pollution is very slight. Contents of most kinds of heavy metals are below the level III of surface water standard, and only very few samples go beyond level III, but they are still below level IV. However, N?P pollution are very heavy both in reservoir and along the river. Contents of most samples in Guanting Reservoir exceed the level IV of lake and reservoir water standard. A few of them even exceed level V. In addition, contents of various species of N change with locations. The pollution in Guanting Reservoir is more serious than Yongdinghe River, and the most serious site is located at bridge No.8 and the estuary following it. In all kinds of species of nitrogen, content of ammonia nitrogen is the highest in the reservoir. And particle phosphorous is the main species of phosphorous pollution. The pollution degrees of N and P can reflect the different sources of pollutants.
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    The Computational Domain Discretion for Hydrological Model
    WAN Hong tao, ZHOU Cheng hu, WAN Qing
    2001, 20 (4):  347-354.  doi: 10.11820/dlkxjz.2001.04.007
    Abstract ( 528 )   PDF (522KB) ( 670 )   Save
    In the lumped hydrological model the temporal hydrological process can be simulated very well with no concern to the spatial distribution and spatial variation of the hydrological variable and hydrological parameters. With the increase of the spatial data and the development of spatial discretion technology, the distributed hydrological model, in which the spatial distribution is concerned, is the research focus in the recent years. In this paper the discretion method, which is used to discrete the computational domain of the distributed hydrological model and flood routing model, is discussed in detail. In the distributed rainfall runoff models there are several computational domain discretion methods, such as representative elemental areas, or REA; hydrological response unit, or HRU; grouped response unit, or GRU; and aggregated simulation areas, or ASA. In the runoff routing model, the computational domain can be discreted into structured mesh and unstructured mesh. The structured mesh can be regular mesh and irregular mesh. In addition, we also elucidate the role of Geographical Information System technology and Remote Sensing in the hydrological model and its computational domain discretion. GIS technology can be used to generate and adjust the irregular and unstructured mesh for the computational domain. In addition, RS can provide the information of relief map and landuse map. Based on the GIS and RS, some necessary hydrological parameters can be derived from the relief map and landuse map.
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    A Research of the Impacts of Uneven Precipitation on the Natural Runoff in the Yellow River
    ZHANG Shi feng, JIA Shao feng
    2001, 20 (4):  355-363.  doi: 10.11820/dlkxjz.2001.04.008
    Abstract ( 385 )   PDF (850KB) ( 885 )   Save
    The impact of uneven precipitation on the runoff amount is very significant in the Yellow River basin. The years of 1983 and 1985 are both rich hydrological years with precipitation of 501 mm and 502 mm, respectively, but the natural runoff amounts of the two years at the Huayuankou station are 76 5 and 63 8 billion m\+3. This means that there is a 12 7 billions m\+3 difference of runoff amount when the rainfalls are almost the same. This paper analyzes the impact of precipitation unhomogeneity on runoff generation. Firstly, the impact of spatial unhomogeneity is analyzed. The normal method is to divide the Yellow river basin into five sections , namely, upper Lanzhou section, Lanzhou-Hekou section, Hekou-Longmen section, Longmen-Sanmenxia section, Sanmenxia-Huayuankou section. When we analyze by using this division, the simulation result in the four sections of lower Lanzhou region is quite good, but the simulation result in upper Lanzhou section is bad. Concretely, the simulation result is that the runoff amount in 1983 is 6 7 billion m\+3 more than that of 1985 in the middle reaches, which is very close to the measured 5 4 billion m\+3. And the result also shows that the reason of the difference of the runoff amount generated in the middle reach is that the precipitation and runoff in the Longmen-Sanmenxia section is different. In the Lanzhou-Hekou section, the difference of precipitation doesn’t impact the runoff very significantly since the precipitation-runoff generation coefficient is very small. The runoff amount generated in this section is very small. The precipitation and runoff in the Hekou-Longmen section and Sanmenxia-Huayuankou section are different but total amounts are very close. Therefore the reason for the difference of water amount is the runoff generation in the upper Lanzhou section and Longmen-Sanmenxia section. According to simulation result through the precipitation-runoff relation, the precipitation and runoff amount in 1983 is less than that of 1985, but the measured figure of precipitation in 1983 is less than that of 1985 while the runoff in 1983 is 7 5 billion m\+3 more than that of 1985. This means that the normal division can not explain the runoff generation characteristics. Then we make further division of the spatial scale by subdivision of upper Lanzhou section into upper Tangnaihai section and Tangnaihai-Lanzhou section. The result is that, although the precipitation of upper Lanzhou section of 1983 is less than that of 1985, the precipitation and runoff of upper Tangnaihai section of 1983 are larger than those of 1985, and the precipitation and runoff of Tangnaihai-Lanzhou section of 1983 keep less than those of 1985, while this upper Tangnaihai section is the so-called high water generation rate section. This result can explain why the runoff of upper Lanzhou section in 1983 is larger than that of 1985 while the precipitation of upper Lanzhou section in 1983 is less than that of 1985. Such a subdivision can clearly indicate that the precipitation and runoff relation in upper Tangnaihai section is dominant in the upper Lanzhou sction. Therefore spatial division must be drawn into Tangnaihai section at least, and the result could explain the precipitation-runoff relation. Secondly, we subdivide the temporal scale into flood period and non flood period. Analysis result shows that such a time scale division doesn’t impact very much of precipitation-runoff relation and that, at the verse, the simulation result of precipitation-runoff relation is worse than that in year-scale.
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    Reanalysis on the Climatic Characteristics of Lhasa During 1904~1907 A.D.
    ZHANG Xue qin, GE Quan sheng
    2001, 20 (4):  364-370.  doi: 10.11820/dlkxjz.2001.04.009
    Abstract ( 413 )   PDF (274KB) ( 507 )   Save
    Historical documents, especially the personal diaries in history, have unique advantages in reflecting climatic events or disaster events, i.e., accuracy in recording time and describing events. Basing on the deep analysis on historical documents, particularly "Weather Diary of Lhasa Recorded by You Tai" lasting from February 9, 1904 to April 17, 1907, the climatic characteristics of Lhasa during this period are summarized as follows. During 1904~1907 A.D., the climate of Lhasa was warm with obvious warm winter, and the temperature of 1905 was warmer than that of 1904. At the same period, it was dominated by dry climate accompanied by temporary periods with rich rain; the weather was diverse with plenty of wind and fog. In addition, the natural disasters occurred frequently, including waterlogging, snow hazard, and drought, etc. Analysis also indicates that the climatic change of Lhasa during 1904~1907 A.D. was generally consistent with that of other regions of China and the world, which implies that the period from the late 19th century and the early 20th century was one transition period from the cold to the warm for the climate of Tibetan Plateau. Combining with other analyses about the proxy records of climatic change, we can approve from the regional angle that the Little Ice Age (LIA) was the most direct background event of current global warming. In the future research, we expect to perfect the understanding about the climatic change characteristics of Lhasa during 1904~1907 A.D., which will be beneficial to the understanding about the climatic change of the whole Tibetan Plateau.
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    The Study of Airborne Pollen and Spores in Hailun of Northeast China Plain
    HUANG Ci xuan, Pierre COUR, XU Qing hai YANG Xiao lan, LIANG Wen dong
    2001, 20 (4):  371-377.  doi: 10.11820/dlkxjz.2001.04.010
    Abstract ( 345 )   PDF (366KB) ( 380 )   Save
    In order to study the airborne pollen and spores, we collected a year round airborne samples at 10 m height above ground from Hailun ecological station, which is located in Hai1un County of Heilongjing Province. The analytical results shows that there are 72 plant families and genera in airborne pollen and spores. Of them, 18 are Xylophyte plants, 52 are herbaceous plants, and 2 are Pteridophyta plants. The main pollen and spore families and genera are Betula, Populus, Salix, Quercus, Artremisia , Chenopodiaceae and Gramineae. There are two peak stages of airborne pollen and spore concentrations throughout the year. One is the peak stage of Xylophyte plants from mid April to end of May and other herbaceous plants from early August to mid September. The maximum year round value is 343 000 grains/1000 m 3 air in the mid dekad of May. The second value is 307 000 grains/1000 m 3 air in end of August, and the minimum value is 100 grains/1000 m 3 air in early February. In the local district, the airborne pollen and spores which can induce respiratory tract disease in spring are Betula and Populus , and those that can induce disease in autumn are Artemisia, Ambrosia , Chenopodiaceae and Gramineae.
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    A Study on Remote Sensing Methods in Estimating Urban Built-up Volume Ratio Based on Aerial Photographs
    ZHA Yong
    2001, 20 (4):  378-383.  doi: 10.11820/dlkxjz.2001.04.011
    Abstract ( 453 )   PDF (651KB) ( 809 )   Save
    The determination of the ratio of urban built-up volume requires the height information or the number of floors of a building. The purpose of this paper is to compare the accuracy of the ratio measured with the direct, the displacement, the shadow and the parallax methods. The number of floors/height of 21 buildings is determined from 1∶2500 and 1∶4000 aerial photographs. The comparative analysis of these results shows that the direct method is the least accurate. Although the parallax method is the most accurate in determining height, its accuracy is next to that of the shadow method in estimating the ratio. The impact of the scale of the photographs used on the estimation of accuracy varies with the height determination methods. With the decrease of scale, the accuracy of the direct method improves, but the shadow and the parallax’s accuracy worsens. Scale hardly affects the accuracy of the displacement method.
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    The Paleoclimatic Records and Paleoecological Paleoenvironmental Meanings of Speleothems
    LIU Qi ming, WANG Shi jie, OUYANG Zi yuan
    2001, 20 (4):  384-390.  doi: 10.11820/dlkxjz.2001.04.012
    Abstract ( 465 )   PDF (828KB) ( 840 )   Save
    It’s one of the important task to reconstruct Paleoclimatic and Paleoecological Paleoenvironmental changes of global change. Based on the microbanding structure, stable oxygen carbon isotope and trace elements, like other natural materials (loess?ice core?tree rings?sea deposits) , Speleothems are important repositories of Paleoclimatic and Paleoecological Paleoenvironmental data. In recent decades, the study of the paleoclimatic records and paleoecological paleoenvironmental meanings of speleothems achieved appreciable progress. The stable oxygen isotopic sequences of speleothems can give information about precipitation and temperature. The history of changing vegetation can be traced by the stable carbon isotopic sequences of speleothems. And much high resolution climatic environment information, such as precipitation, temperature, soil and vegetation, is involved in microbanding type and trace elements character of stalagmite. This paper is intended to review and synthesize the recent advances. It also points out the existing problems and forecasts the developing trends toward.
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