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    25 July 2003, Volume 58 Issue 4 Previous Issue    Next Issue
    Estimation of Ocean Primary Productivity by Remote Sensing and Introduction to Spatio-temporal Variation Mechanism for the East China Sea
    LI Guosheng, WANG Fang, LIANG Qiang, LI Jilong
    2003, 58 (4):  483-493.  doi: 10.11821/xb200304001
    Abstract ( 730 )   PDF (1529KB) ( 834 )   Save

    According to calculation results of ocean chlorophyll concentration based on SeaWiFS data by SeaBAM model and synchronous ship-measured data, this research set up an improved model for Case-I and Case-II water respectively. The monthly chlorophyll distributions in the East China Sea in 1998 have been obtained from this improved model on the calculation results of SeaBAM. The relative coefficient analysis between the ship-measured chlorophyll concentration and the calculation results of the improved model shows that the relative coefficient is 0.5752, which means they have obvious dependence. The fact that the coefficient of linear regressive equation is nearly 1 confirms their dependence further. Therefore, it can be said for certain that the improved model is suitable for calculation of the chlorophyll distribution for Case-I and Case-II water in the East China Sea. The euphotic depth distribution in 1998 in the East China Sea is calculated by using remote sensing data of K490 from SeaWiFS according to the relation between the euphotic depth and the oceanic diffuse attenuation coefficient. With the data of ocean chlorophyll concentration, euphotic depth, ocean surface photosynthetic available radiation (PAR), daily photoperiod and optimal rate of daily carbon fixation within a water column, the monthly and annual primary productivity spatio-temporal distribution in the East China Sea in 1998 have been obtained based on VGPM model. Based on analysis of those distributions, the conclusion can be drawn that there is a clear bimodality character of primary productivity in the monthly distribution in the East China Sea. In detail, the monthly distribution of primary productivity stays lowest level in winter and rises rapidly to the peak in spring. It gets down a little in summer, and gets up a little in autumn. The daily average of primary productivity in the whole East China Sea is 560.03 mg/m2/d, which is far higher than the average of subtropical ocean areas. The annual average of primary productivity is 236.95 g/m2/a, which is fit with the primary productivity obtained from the investigation in the Kuroshio zone in the East China Sea. The research on the seasonal variety mechanism of primary productivity shows that several elements that affect the spatio-temporal distribution may include the chlorophyll concentration distribution, temperature condition, the Yangtze River dilute water variety, the euphotic depth and ocean current variety etc. But the main influencing elements may be different in each local sea area.

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    The Comparison of Land Surface Temperature with CLM and Split Window Retrieving Method
    GAO Zhiqiang, LIU Jiyuan
    2003, 58 (4):  494-502.  doi: 10.11821/xb200304002
    Abstract ( 874 )   PDF (1267KB) ( 729 )   Save

    In this paper, the Common Land Surface Model (CLM) and split window retrieving method were employed to compute and retrieve land surface temperature along transects, and then the spatial distribution and errors of two kinds of land surface temperatures from different ways were analyzed and compared based on the observed temperature, the applicability of two ways was decided by the comparison results. The conclusions drawn by this study are as follows: the land surface temperature simulated with CLM matches best with that from observed in distribution, but because of the impacts of different topographic types and land covers the errors of water surface temperature simulated with CLM to land surface temperature are greater (errors > 3%), the errors of cultivated land surface temperature are smaller (errors < -3%), the surface temperatures of barren land, grassland and forest match best with observed values. The land surface temperatures with split window method differ obviously from that observed. The split window method is applicable to retrieve the temperature of grassland and forest, but it has significant errors to retrieve the surface temperatures of barren land and cultivated land.

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    The Valuation of Ecological Services from the Vegetation Ecosystems in the Qinling-Daba Mountains
    REN Zhiyuan, Li Jing
    2003, 58 (4):  503-511.  doi: 10.11821/xb200304003
    Abstract ( 896 )   PDF (1333KB) ( 625 )   Save

    Based on the characteristics of eco-environment in the Qinling-Daba Mountains of Shaanxi Province, according to differences of the vegetation types and coverage in the Qinling-Daba Mountains, combined with the advance of new research, this paper explores the theory and methods for the valuation of the vegetations ecosystem services, establishes the data basis of vegetation ecosystem, GIS and vegetation eco-account. By determining vegetation productions and eco-adjusted mass, taking advantage of the theory and methods on ecology-economics, the paper studies the value of the vegetation ecosystem services. The results show that: (1) the value of land-vegetation's primary productivity is 199.6 billion yuan/a; (2) the value of vegetation's soil and fertilization conservation is 22.64 billion yuan/a; (3) the value of vegetation water conservation is 22.66 billion yuan/a; (4) the value of fixing CO2 and releasing O2 is 352.24 billion yuan/a and 374.19 billion yuan/a respectively; and (5) the total value of ecosystem services is 968.33 billion yuan/a. The rate of contribution to the temperate deciduous broad-leaved forest is the highest, accounting for 29.35% of the total value.

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    The Relationship of NDVI and Climatic Factors under Different Radiation Dryness Indexes
    ZHOU Tao, YI Chuixiang, SHI Peijun
    2003, 58 (4):  512-518.  doi: 10.11821/xb200304004
    Abstract ( 678 )   PDF (764KB) ( 709 )   Save

    The global 1*1 degree grid data were used to analyse the relationship between NOAA/AVHRR NDVI and the climatic factors which include multi-year average precipitation (Pcp), multi-year averaged net radiation (Netrn), and multi-year average radiation dryness index (RDI) from 1986 to 1990. The results showed that: (1) There, as a whole, existed a logarithmic relationship between NDVI and RDI, Pcp; whereas NDVI and net radiation (Netrn) had a linear relationship. (2) The correlations of NDVI with precipitation and net radiation had great difference under different RDI scopes. When RDI was less than 1, there existed a nonlinear relationship between NDVI and precipitation and net radiation; when RDI was greater than 1 and less than 2, the nonlinear relationship of NDVI and precipitation was a little better than linear relationship; when RDI was greater than 2 and less than 10, they had an apparent linear relationship; when RDI was greater than 10, their correlations were rather weak. (3) Based on 13 global vegetation types, the correlations of NDVI and Pcp, Netrn, RDI were different in different vegetations. The hierarchical cluster analysis showed that the correlations of NDVI with Pcp and Netrn could be divided into 4 categories.

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    Exploration of Eco-environment Range in the Source Regions of the Yangtze and Yellow Rivers
    DING Yongjian, YANG Jianping, LIU Shiyin, CHEN Rensheng, WANG Genxu, SHEN Yongping, WANG Jian, XIE Changwei, ZHANG Shiqiang
    2003, 58 (4):  519-526.  doi: 10.11821/xb200304005
    Abstract ( 538 )   PDF (1293KB) ( 754 )   Save

    On the basis of geographical and hydrological ranges definition, four principles are determined, which are the foundation for deciding the extents of the source regions of the Yangtze and Yellow rivers, in this paper. Under the comprehensive analysis of topographical characteristics, climate conditions, vegetation distribution and hydrological features, ranges of the source regions of eco-environment study are defined. The Dari hydrological station is the eastern boundary point of the source region of the Yellow River which drains an area of 4.49×104 km2. The eastern boundary point is the convergence point of the Nieqia and the Tongtian rivers in the source region of the Yangtze River, which drains an area of 12.24×104 km2.

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    Net Water Natural Loss in the Main Channels of the Yellow River
    LI Chunhui, YANG Zhifeng
    2003, 58 (4):  527-533.  doi: 10.11821/xb200304006
    Abstract ( 739 )   PDF (808KB) ( 626 )   Save

    The interactions between river runoff and air water exist in the forms of precipitation and evaporation. These interactions are parts of "four waters" interactions. Only consumed water and changing volumes of reservoirs are recalculated in the natural runoff recalculation and the water natural loss in the river channels have been deducted, so it is important to know the changes of natural runoff controlled by hydrological stations at river sections from quantitative analysis of the net water natural loss in the river channels, especially in the main river channel. First, the water balance equation is set based on the water balance principle to find the relationships between QRN, QC, P and QL in the river channel. Then the net water natural loss in six main river channels of the Yellow River are calculated. At last, the varieties of the net water natural loss in the main channels of the Yellow River are analyzed, and the conclusions are: (1) The water supplement is more than loss in the regions of Hekouzhen-Longmen and Sanmenxia-Huayuankou, while the water supplement is less than loss in the other regions in the river channels of the Yellow River. (2) Since 1960, the net water supplement has got less and less in the regions of Hekouzhen-Longmen and Sanmenxia-Huayuankou, but the net water natural loss is more and more in the other river channels. In all, the net water natural loss in the river main channels is increasing gradually and the value is 44.16×108 m3 in the 1990s. (3) The over-exploitation of groundwater is the essential reason for the increase of net water natural loss in the Yellow River.

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    The Renewability of Water Resources and Its Quantification of the Yellow River Basin in China
    XIA Jun, WANG Zhonggen, LIU Changming
    2003, 58 (4):  534-541.  doi: 10.11821/xb200304007
    Abstract ( 498 )   PDF (1077KB) ( 527 )   Save

    The drying-up event in the lower reaches of the Yellow River during the 1990s was the most serious problem of water resources issues in China that involved the concept of water resources renewability in the Yellow River basin. The problem of renewability linked with hydrological process affected by climate change and human activity was addressed in this paper. A quantitative method was developed to analyse causes and to propose countermeasures to improve renewability of water resources. The magnitude of renewability and change in time and space within the river system can be represented using this method. According to the analysis of observation data set, the renewability of water resources of the Yellow River basin has had a significant declining trend since the 1950s. Specially, the renewability indicator in the downstream has reduced 0.2 with a worse situation of the 1990s. By renewability assessment, some of the workable countermeasures can be analyzed.

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    The Influence of Groundwater on Vegetation in the Lower Reaches of Tarim River, China
    CHEN Yaning, LI Weihong, XU Hailiang, LIU Jiazhen, ZHANG Hongfeng, CHEN Yapeng
    2003, 58 (4):  542-549.  doi: 10.11821/xb200304008
    Abstract ( 637 )   PDF (1082KB) ( 610 )   Save

    Results of the analyses of the monitored data of the 4 times of stream water conveyance to the river section where the stream flow was cut-off more than 30 years, of the nine groundwater-monitoring sections and 18 vegetation plots in the lower reaches of the Tarim River from 2000 to 2002, show that the composing and type of vegetation, the distribution and the way vegetation is growing closely related to the depth of groundwater; the continuously decreasing of the groundwater and the loss of soil water are the main factors for the degradation of vegetation in the lower reaches of the Tarim River; the 4 times of stream water conveyance to the dry up of the lower reaches of the river plays an important role in raising the groundwater level, which is close to the watercourse. The groundwater was raised gradually. The transverse response scope of groundwater level was gradually enlarged to about 1,000 m after the fourth conveyance and the lift range of groundwater level is the highest in the upper section (84%), median in the middle section and the lowest in the lower section (6%) longitudinally. The natural vegetation in the lower reaches is saved and restored along with the rise of groundwater level, the response scope of vegetation is gradually enlarged, i.e., from 200-250 m in width after the first conveyance to 800 m after the fourth conveyance.

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    Modern Changes of the Climate and Glaciers in China's Monsoonal Temperate-Glacier Region
    HE Yuanqing, ZHANG Zhonglin, YAO Tandong, CHEN Tuo, PANG Hongxi, ZHANG Dian
    2003, 58 (4):  550-558.  doi: 10.11821/xb200304009
    Abstract ( 559 )   PDF (1256KB) ( 696 )   Save

    Climatic data, ice core records, the tree ring index and recorded glacier variations have been used to reconstruct a history of climatic and glacial changes in the monsoonal temperate-glacier region of southwestern China during the last 400 years. All the results indicate that the temperature in the region increased in a fluctuating manner during the 20th century, after the two cold stages of the Little Ice Age during the 17th-19th centuries, with a corresponding retreat of most of the glaciers against a background of global warming. However, the amount, trend and amplitude of variation of precipitation have differed in different parts of the region. The climatic records in the Dasuopu ice core, from the Himalaya area in the western part of the region, show a decreasing trend of precipitation, the converse of the trend of temperature. In the Hengduan Mountains and other areas of the eastern part of the region, however, a rising trend of rainfall has accompanied increasing temperatures, as a result of the variable atmosphere circulations from different sources. The data indicate that the southwestern monsoon, which is the principal controlling factor in the Chinese monsoonal temperate-glacier region, can be classified into two parts. One is the Indian monsoon from the Arabian Sea, passing across the Indian Peninsula. This transports the vapour for precipitation in the Himalaya area, the western part of the monsoonal temperate-glacier region. The other part is the Bengal monsoon from the Bay of Bengal, passing over Bangladesh and Burma. This is the major source of precipitation in the Hengduan Mountains and other areas of the eastern part of the region. In addition, the eastern part is influenced by the southeast monsoon from the western Pacific, whilst the western part is affected by the southern branch of the westerly circulation in winter. This complex atmospheric situation results in different patterns of precipitation in the western and eastern zones.

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    Influence of Arctic Oscillation on Winter Climate over China
    GONG Daoyi, WANG Shaowu
    2003, 58 (4):  559-568.  doi: 10.11821/xb200304010
    Abstract ( 687 )   PDF (1199KB) ( 1074 )   Save

    In this study the relationships between the Arctic Oscillation and climate in China in boreal winter are investigated. The data used in this study include NCEP/NCAR Reanalysis monthly mean sea level pressure, 500 hPa geopotential heights, two Arctic Oscillation indices, and the observed temperature and precipitation. Correlation analysis for the last 41 years shows that the winter temperature and precipitation in China change in phase with AO. High positive correlation between temperature and AO is above +0.4 and appears in the northern China. High correlation coefficients between precipitation and AO cover the southern China (close to the South China Sea) and the central China (between 30o-40oN and east of ~100oE), with the values varying between +0.3 and +0.4. The correlation between the 160-station average temperature and the simultaneous sea level pressure show that the winter temperature of China is strongly connected to the sea level pressure over the high latitudes of Eurasia continent. The center is located in Siberia with values lower than -0.6. The partial correlation between the intensity of Siberian High and averaged temperature in China remains -0.58, when AO keeps constant. But the partial correlation between temperature and AO is only 0.14 when the influence of Siberian High is excluded. The relationship between AO and precipitation is also significant. The partial correlation between AO and mean precipitation of 160 stations is 0.36. But when the AO's influence is excluded, the partial correlation between the intensity of Siberian High and precipitation is only -0.16. This suggests that during the past several decades the precipitation was strongly affected by AO, but for the temperature the Siberian High plays a more important role. AO and the Siberian High correlate at -0.51, according to the data for the period 1958/59-1994/95. The possible dynamical connection between AO and the Siberian High needs further study. Using the long-term series of AO and the Siberian High spanning 1899/1900-1994/1995, their connections to climate in China are analyzed too. At the interdecadal time scale the AO shows significant influence on both temperature and precipitation. Partial correlation between AO and temperature is 0.66. For precipitation the correlation coefficient is 0.70.

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    Interdecadal Variability of East-Asian Summer Monsoon and Its Impact on the Climate of China
    GUO Qiyun, CAI Jingning, SHAO Xuemei, SHA Wanying
    2003, 58 (4):  569-576.  doi: 10.11821/xb200304011
    Abstract ( 662 )   PDF (1142KB) ( 713 )   Save

    Interdecadal variabilities of East-Asian summer monsoon are studied according to the sum of sea level pressure gradient which is ≤-5 hPa between the land (110oE) and sea (160oE) from 10oN to 50oN. The sum for each year from 1951 to 2000 is divided by the mean sum averaged for the total 50 years, to form a series of Summer Monsoon Index (SMI). It shows a systematic reduction during the period of 1951-2000. Strong monsoon (SMI ≥1.0) was predominated during the first half of the studied period. SMI was less than 1.0 since 1976. Association of the climate in China to the SMI is examined based on the calculation of correlation coefficients between monthly mean temperatures and precipitations in each of 160 stations covered the whole land area of Chinese territory. It indicates that summer (June to August) precipitation increased in North China and decreased along the lower reaches of the Changjiang River when summer monsoon was stronger than the normal, and vice versa. Summer temperatures were higher along the Huaihe and Changjiang rivers when summer monsoon was stronger than the normal.

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    Climate Change of Extreme Precipitation in Xinjiang
    YANG Lianmei
    2003, 58 (4):  577-583.  doi: 10.11821/xb200304012
    Abstract ( 1325 )   PDF (934KB) ( 983 )   Save

    Based on the day-to-day observed data of precipitation from 55 meteorological stations in Xinjiang from 1961 to 2000, the climatic variations, tendencies and distribution of extreme precipitation have been analyzed during the last 40 years. The climate jumps have been examined in terms of 3-year moving averaged seasonal and annual series of extreme rainfall and frequency using Yamamoto method and Mann-Kendall method. Regional ecological environments have been changed tremendously after large-scale reclamation since the 1950s at the northern foot of the Tianshan Mountains and Aksu area. Rainfall and frequency of extreme precipitation have an increasing tendency in the two areas since the 1980s. Under the special geographical conditions and climate background, the changes resulted from variations of regional eco-environments and climate are induced by human activities. The results obtained are as follows: Quantity and frequency of extreme precipitation have an obvious increasing tendency at the northern foot of the Tianshan Mountains and Aksu area, especially since the 1980s, there is a climate jump of annual extreme precipitation in 1980; the linear tendencies of annual extreme precipitation are 24.5%/10a in Aksu area, 19.5%/10a at the northern foot of the Tianshan Mountains; the linear tendency of frequency increases by 20%/10a in Aksu area, and 14.5%/10a at the northern foot of the Tianshan Mountains. In other areas there are no obvious variations. Climate change of extreme precipitation is from variation of extreme rainfall in summer. The percentage that extreme precipitation takes up in annual precipitation: the Tianshan Mountions is 41.9%, northern Xinjiang and Hotan region are 17.2% and 1.9% respectively, the other areas are 25%-31.3%.

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    The Vulnerability of Regional Land Productivity to Global Climatic Change: The Case of the Middle Part of Agricultural-Pastoral Zigzag Zone in Northern China
    ZHAO Xinyi, CAI Yunlong
    2003, 58 (4):  584-590.  doi: 10.11821/xb200304013
    Abstract ( 615 )   PDF (839KB) ( 772 )   Save

    The impact of global change, especially the global climatic change on human beings has become one of the most serious problems throughout the world. Because of the uncertainty of climatic change, the assessment of the response to climatic change is more necessary and available than the study on the impact of climatic change, especially on the regional scale, which is concerned with the regional strategies to climatic change and the regional sustainable development. Now the vulnerability is taken as the index to express the response of one region to climatic change, which is the function of both the sensitivity to climate and the adaptability to new conditions. The index will make the research work from different scientists comparable and push ahead the study on the impact of climatic change in the world. The middle part of the agricultural-pastoral zigzag zone in northern China is taken as the case area in the paper, which has changeable climate on the temporal and spatial scales. Both the sensitivity of and the adaptability to climate change of the land production in this area are calculated. The character of this paper lies in: the creation of climate scenario in the future based on the information from different sources, the calculation of sensitivity index by the experiential or statistical relationship of land productivity and climate change, and the assessment of the adaptability using the data from the social and economic yearbooks.

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    Seasonal Sedimentary Effect on the Changjiang Estuary Mud Area
    GUO Zhigang, YANG Zuosheng, FAN Dejiang, Pan Yanjun
    2003, 58 (4):  591-597.  doi: 10.11821/xb200304014
    Abstract ( 674 )   PDF (791KB) ( 727 )   Save

    The seasonal distributions of suspended matter and their sedimentary effect on the Changjiang (Yangtze River) Estuary mud area (CEMA) were discussed, based on the three cruise data of total suspended matter, temperature and salinity collected in the Changjiang Estuary and its adjacent area in summer and winter. The results showed that the basic pattern of distributions of suspended matter in the CEMA and its adjacent area is almost the same in winter and summer. It is indicated that the sediments from Changjiang to the sea are almost trapped on the inner shelf west of 123o15'E, due to the strong obstruction of the Taiwan Warm Current (TWC), supporting that the sediments from Changjiang to the sea are mainly transported and deposited on the inner shelf. The sediment supply from Changjiang to the sea, TWC, Zhejiang Coastal Current (ZCC) and Changjiang Diluted Water (CDW) show a strong seasonal variation, resulting in the strong seasonal sedimentary effect on the CEMA. The sedimentation of this mud area is stronger in summer and weaker in winter. The CEMA is a "sink" of the sediments from Changjiang to the sea. It is suggested that the amount of sediments deposited in this mud area in summer is much more than that in winter. The sedimentation processes of the CEMA and southwest Cheju Island mud area are characterized by a strong seasonal variation, but the processes of the two mud areas are very different. The sedimentation of the southwest Cheju Island mud area is stronger in winter and weaker in summer.

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    The Distribution of Ephemeral Vegetation on the Longitudinal Dune Surface and Its Stabilization Significance in the Gurbantunggut Desert
    WANG Xueqin, JIANG Jin, LEI Jiaqiang, ZHANG Weimin, QIAN Yibing
    2003, 58 (4):  598-605.  doi: 10.11821/xb200304015
    Abstract ( 996 )   PDF (1122KB) ( 875 )   Save

    Field surveys of vegetation were conducted in the southern area of the Gurbantunggut Desert from March to August 2002. Vegetation cover was measured using 6 quadrats at different geomorphic positions on the longitudinal dune. Species numbers, coverage and growth of plants were recorded. Distributions of ephemerals on the dune surface were obtained, and the stabilization significance of the distribution ephemerals on the longitudinal dune surface in Gurbantunggut Desert was discussed. Threshold wind data from the Cainan meteorological station covering 1994 to 1995 were also analysed. A total of 45 species were recorded at the study site, of which 29 species were ephemerals. They formed special spring synusiae communities, of which Alyssum linifolium and Erodium oxyrrhynehum were the dominant species. At the peak of the ephemeral growth cycle most of the above-mentioned ground biomass was measured between surface level and a height of 30 cm, and root density was the greatest, ranging between 0 and 30 cm. The temporal and spatial distributions of ephemerals are unique. Their germination period is from late March to early April. Most of the ephemerals end their life-cycle according to climatic conditions. This usually occurs sometime between the last 10 days of June and the first 10 days of July. The average coverage of ephemerals on the interdune corridor and the two plinths reached 13.9% in March, 40.2% in April and 14.1% in June. Ephemeral coverage also varied in different zones of the dune. Spring coverage was 40.2% on the interdune, 44.9% on the plinth and 4.4% on the crest.

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    Particle Size Analysis of Aeolian Dust Derived from Duststorm and Non-duststorm
    WANG Zanhong
    2003, 58 (4):  606-610.  doi: 10.11821/xb200304016
    Abstract ( 391 )   PDF (686KB) ( 600 )   Save

    The collected samples under typical duststorm and non-duststorm weather were used to make a particle size analysis, the results showed that there are many differences between the two samples. First, aeolian dust derived from duststorm has a light yellow colour while dark brown-yellow from non-duststorm, on which the two samples can be distinguished by eye. As a whole, both samples of duststorm and non-duststorm are essentially composed of two relatively common groups of grain with sizes of 5-6φ and >8φ. With poor sorting, dust derived from storm is courser than that from non-storm. The particle size distribution of sample derived from duststorm is approximatively normal while that from non-duststorm is bimode, which can be explained by the coaction of far and near existent sources and violent wind power sweeping course and fine grains. Compared with the particle size distribution of loess-paleosol with eolian cause of formation, modern eolian dust presents largely similarity to the ancient dust accumulation. Hint thus is given that modern aeolian sedimentary process in vogue continues from geological history and modern dust accumulation has ingenerated relationship with the ancient sediment.

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    Assessment and Empirical Study on the Relationship between Infrastructure Construction and Urban-Rural Development
    ZHAN Jinyan, LU Qi
    2003, 58 (4):  611-619.  doi: 10.11821/xb200304017
    Abstract ( 458 )   PDF (1257KB) ( 770 )   Save

    Urban-rural development has always been illustrated as the interdependent and interaction relationship, represented by the free flow of population, commodities, capital and information between urban and rural areas, which, in some sense, guarantees the effective and efficient uses of resources in urban and rural areas. It is self-evident that the construction of regional infrastructure is a precondition for regional urbanization.The improvement of public infrastructure shortens the "spatial distance" between urban and rural areas, widens the built-up areas, pushes outside the urban fringe and forms, in some time, a new form of spatial complexity in which urban and rural areas are intensely mixed or "interlocked". The joint development of urban and rural areas depends on the increase of capital investment for infrastructures mainly cover transportation, telecommunication, education, medical facilities and welfare. We can safely come to a conclusion that regional infrastructure is indispensable to the development of urban and rural areas and lays the foundation for the relationship generation between regional infrastructure and urban-rural development. On the other hand, the strong interaction between urban and rural areas will promote the construction and improvement of regional infrastructure. Many scholars have paid much attention to the relationship between regional infrastructure and urban-rural development now. It has important implications for the construction of infrastructure and improvement of social and economic benefits to find out and assess the relationship between regional infrastructure and urban-rural development.

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    Cultivated Land Change in Urbanization Process of Shijiazhuang City
    ZHANG Junyan, JIA Shaofeng, GAO Ting
    2003, 58 (4):  620-628.  doi: 10.11821/xb200304018
    Abstract ( 618 )   PDF (1270KB) ( 827 )   Save

    Based on remote sensing images of 2000 and the land use vector map of 1995, through superposing and analyzing, we achieve the tempo-spatial process of land use change from 1995 to 2000 in Shijiazhuang City. By using data obtained from interpretation of remote sensing images and other statistical sources, we analyzed land use change patterns in Shijiazhuang City and their driving forces. The main conclusions include: (1) The main characteristics of the city's land use change are the obvious reduction of the cultivated land and the subsequent rapid increase of the constructive land, with the maximum increase of land area of single enterprise or mine land use type through taking up cultivated land. This shows a dissimilar pattern of cultivated land decrease with the whole country and some other regions. In China and the Bohai Rim, the main reason for cultivated land decrease is structural adjustment within agricultural sector. In Shijiazhuang City, the contribution of cultivated land decrease to structural adjustment in agricultural sector makes up only 38% of the total decrease, while that to occupation by construction land use makes up 52.3%. (2) As to spatial pattern, the cultivated land decrease in most counties of plain area and increase in few counties in mountainous area result from the exploitation and resuming cultivation of barren land. (3) Humanistic driving forces are the main reason for the cultivated land change in Shijiazhuang which include economic factor, population factor and policy factor. (4) The urban land use gives little help to the reduction of the cultivated land. Data show that the decrease of the cultivated land is inferior to the increase of urban level from which we know the use of cultivated land in Shijiazhuang is suitable. (5) At present, the urbanization process in Shijiazhuang is only in initial stages. About 2/3 of land use increase for non-agricultural use contributes to the occupation of township and rural enterprises. If there is no regulation and planning to control, land use for this purpose would be overdone.

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    Economic Development and Its Bearing on CO2 Emissions
    ZHANG Lei
    2003, 58 (4):  629-637.  doi: 10.11821/xb200304019
    Abstract ( 759 )   PDF (1349KB) ( 852 )   Save

    Greenhouse-gas (GHG) emissions in China have aroused much interest, and not least in recent evidence of their reduction although the country is not subject to any emissions reduction target under the Kyoto Protocol's first emission control period. Our intent is to place that reduction in a larger context, that of the process of industrialization. A lengthy time perspective is combined with a cross-sectional approach--China plus five other countries--and addressed through two general models. The findings are salutary. First, they suggest that a diversified economic structure is consistent with diminished intensity in energy use. Secondly, and the obverse of the first, they imply that a diversified energy structure promotes reductions in CO2 emissions. Finally, one is led inevitably to the conclusion that, together, the findings point to a path for countries to transform their economies while at the same time undertaking to drastically moderate their energy use, switching from a pattern of heavy carbon emissions to one in which lighter carbon emissions prevail. The implications of such findings for environmental management are enormous.

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