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  • 2004 Volume 24 Issue 1
    Published: 20 January 2004
      
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  • Modeling Analysis of Regional Support on Chinese urbanization
    LI Cheng-Gu, LIU Xi-Feng, LI Pei-Xiang
    2004, 24(1): 1-6. https://doi.org/10.13249/j.cnki.sgs.2004.01.1
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    Aiming at accelerating Chinese urbanization and integrating development of city and region, threading of dynamical factor analysis, the article researches on the metropolis area. By utilizing SPSS means and multiple statistical analysis model, dynamic analysis is carried on and mathematics model of correlation is built between urbanization and regional development of Chinese megalopolis region. At the same time, character and mechanism of interrelation between urbanization ration, non-agricultural population, acreage of built area and regional development is discussed. Base on above, the main way to get sustainable development of Chinese metropolitan area is given.
  • Influence of Traffic Passages on Housing Spatial Expansion and Local Residents' Selection of Housing Location—A Case Study of Beijing
    ZHANG Wen-Zhong, MENG Bin, LU Xin, LIU Wang
    2004, 24(1): 7-13. https://doi.org/10.13249/j.cnki.sgs.2004.01.7
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    With the deepening of the housing system reform in China, the real estate market has gradually assumed an initiative shape along with tremendous changes in the city's housing spatial structure. Based on filed investigation and spot checks, this paper tries to set up a database of housing in Beijing and produce a map of housing spatial distribution.Firstly, the paper studies the traffic passages and the trend of housing spatial distribution and expansion. The authors believe that there exist strong relations between traffic passages and housing spatial distribution and expansion. Areas along main traffic lines, exits and entrances of expressways and areas around subway and light rail stations always become the best locations for agglomeration and development of urban housing. Beijing's housing spreads along the city's main stem and assumes a shape of concentric circles.Secondly, by means of GIS and field study, we research the relationship between Beijing's housing spatial distribution and traffic passages and the influence of fast traffic passages on local residents' selection of housing location. We deem that the construction of traffic passages can improve the accessibility to the existed housing and propel the value increase of along-passage lands. Meanwhile, it can also widen people's selection of housing location, thereby providing a potential profit guarantee for the development and construction of new housing projects.Finally, using questionnaires we analyze the influence of traffic conditions on residents' selection of housing location. We hold the opinion that when selecting the housing location, urban residents often put more attention on the traffic conditions. As a result, those housing projects boasting traffic convenience are easy to sell with comparatively high prices. Therefore, traffic conditions must be taken into account in the development of a housing project which should be adapted to the construction of fast traffic passages and main roads.
  • Macro-Analysis of Cultivated Land Non-Agriculturalization in Zhejiang
    TAN Yong-Zhong, WU Ci-Fang, MOU Yong-Ming
    2004, 24(1): 14-19. https://doi.org/10.13249/j.cnki.sgs.2004.01.14
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    Cultivated land non-agriculturalization (CLNA) is one of the main characteristics of land use at the stage of rapid development of economy. It is a cost for realizing the urbanization and industrialization. The indexes of society and economy development in Zhejiang during 1990-1999 such as CLNA area, popularity, GDP, gross value of industrial output, industrialization rate and urbanization rate are counted and analysed in this paper. Some results are obtained. (1) The CLNA area in Zhejiang during 1990-1999 is 70 878.85 ha and the rate of the CLNA is 3.01%. The rate of the CLNA per year is 0.32% and it is 1.6 times as high as average rate of the whole county. (2) Being influenced by the periodicity of economy, policy of land management and the distribution of economic activities, the CLNA shows fluctuation and regionalism. (3) The non-agriculturalization of agricultural population is on the whole in pace with the non-agriculturalization of cultivated land in Zhejiang after 1996. (4) The potentiality of raising intensive use degree of construction land is great. (5) The relatively large scale CLNA in Zhejiang will continue for a period of time. However, the protection of cultivated land is an eternal theme of land management in China as well as in Zhejiang. The suggestions of slowing down the CLNA are put forward in the paper. They are raising hard the intensive use degree of existing urban land, increasing consolidation of rural residential area land and strengthening the building of institution of the protection of cultivated land.
  • Climate-Soil Productivity and Potential Population Supporting Capacity of Cropland in Sichuan Province
    HE Yu-Rong, ZHOU Hong-Yi, ZHANG Bao-Hua, GONG A-Du
    2004, 24(1): 20-25. https://doi.org/10.13249/j.cnki.sgs.2004.01.20
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    Cropland potential productivity in Sichuan Province is estimated by soil quality index. Most soil quality index is less than 0.70. The area of the first, second and third grade cropland is 185 447 ha and accounts for 42.5% of the total cropland in Sichuan, and the area of the fourth grade and others grade with low yield makes up more than 50% of the total (the second time general investigation of soil resource of China). The climate-soil productive potentiality of Sichuan are 10.7?1010 kg and 69.8? 109 kg with the area cited from the second time general investigation of soil resource of China and statistic of 2001, respectively. According to the climate-soil productive potentiality of Sichuan, the food supply will fail to meet the people's need and will lack 52.4?108 kg and 16.8?107 kg using the linearity model and the exponent model to forecast the population and the area of cropland in 2040, the population of 3863400-12012000 will suffer from shortage of food. If using the actual production capacity to calculate, it is concluded that the population bearing capacity will be overloaded from 2000.In the next 50 years, 8874259-29822803000 kg of grain will be short and the population of 203654000-68401000 preson will be overloaded in Sichuan Province. The result showed that overloaded population-bearing capacity and the shortage of food will not be avoided and the situation will also be austere.
  • Analysis of Dynamic Changes and Driving Forces of Cultivated Land in Hunan Province
    XIONG Ying, WANG Ke-Lin, LU Hui-Hong, XU Lian-Fang
    2004, 24(1): 26-30. https://doi.org/10.13249/j.cnki.sgs.2004.01.26
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    According to statistical and survey data from 1949 to 1999, dynamic changes of quantitative and regional differences of cultivated land in Hunan Province during the last 50 years are analysed. Based on which, the mechanism driving forces for the effect of the economy and population on the change in the cultivated land ares is dealt with in this article.The results indicates that the general trend of cultivated land during the past 50 years was decreasing and regional differences of cultivated land was very notable. The idiographic factors influencing the dynamic change of cultivated land quantity include: (1)the increasingly strong conflict from non-agricultural activities and construction,such as urbanization,industrialization, township and village infrastucture construction land;(2)the farmer's incomes from planting is much lower than the output for the means of agricultural production,casuing jeopardizing farmer's enthusiasm in cultivation activities and adjusting the structure of utilization in cultivatied land;(3)some inappropriate points in the present policies and land management and so on. In addition, the economic growth is the dominant macro-driving factor in decrease of cultivated land area in Hunan Province. The rapid decrease of cultivated land area coincided in time with the overheated economic growth resulting from the direct investment in fixed assets. The spatial distribution patterns for the decrease in arable land matched the differences in speed and scale of economic growth between different regions of the Hunan.
  • Evaluating Loss of Rice Yield Caused by City Expansion in Recent 17 Years—A Case Study of Changshu City from 1984-2001
    ZHANG Ding-Xiang, PAN Xian-Zhang, LI Xian-Wen, SHI Xue-Zheng, YU Dong-Sheng
    2004, 24(1): 31-36. https://doi.org/10.13249/j.cnki.sgs.2004.01.31
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    Using multi-source remote sensing data, four vector maps of expanding towns of Changshu City from 1984 to 2001 are acquired, and a soil database is constructed based on the Second Soil Survey of study area. By a concept soil productivity index (SPI) model combined with soil database, the loss of rice yield and paddy soil productivity caused by urban expansion are evaluated from 1984 to 2001. The model can be used to evaluate soil productivity and the yield of rice at certain management level. As a whole, the productivity of paddy soil is high in Changshu. The extending urban construction has invaded about 2,438 ha of paddy field among recent 17 years, which causes about 20,000 tons of the loss of rice at a management level today. The most of the cropland occupied by urban expanding has high or middle productivity. The loss of average yield of rice is about 8 160 kg/hm2. The soil productivity index (SPI) model can be used to evaluate the distribution of paddy soil productivity and the loss of rice yield caused by urban expansion.
  • Study on the Balance of Datum Land Price Among Cities
    WANG Qing-Gai, ZHENG Xin-Qi, YAN Hong-Wen, BAI Jun-Hong
    2004, 24(1): 37-41. https://doi.org/10.13249/j.cnki.sgs.2004.01.37
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    The balance of urban datum land price is based on the gradation of urban land quality and is made considering the discrepancy among different cities and the land price level of the market.The premise of realizing the balance of urban datum land price is the unification of the land price implication and conditions. The stipulation of land price implication is the radical procedure, or else the land price of different cities can not be compared and it is difficult to realize the balance of urban datum land price. The unification of the land price implication is realized by a series of formulas.After the gradation of urban land quality and unification of urban datum land price implication, the datum land price of every grade towns is computed. The datum land price of every grade cities is stipulated by averaging the datum land price of all the cities and consulting advice of experts. The range of the urban datum land price is stipulated according to the range of the datum land price of each grade of each town and the sample land of the special land. The range of the urban datum land price is made according to different type and different grade.
  • Relationship Between Climate Variation and Surface Water Resources in Northeast China
    SUN Li, AN Gang, GAO Zong-Ting, REN Hong-Ling, TANG Xiao-Ling
    2004, 24(1): 42-49. https://doi.org/10.13249/j.cnki.sgs.2004.01.42
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    By using the 53-year NCEP/NCAR reanalysis monthly mean data for the period 1948-2000, the influences of the temperature and/or precipitation on the surface water resources (surface potential evaporation, surface runoff, 0-10cm soil moisture content and 10-200cm soil moisture content) in Northeast China in different seasons have been studied. The simple statistical evaluation models about the influence of the temperature and/or precipitation on the variables of the surface water resources have been also established. Based on these models, the responses of the variables of the surface water resources in Northeast China to the different climate variations have been assessed. The results are summarized as fallows:The temperature variation in Northeast China has some influence on the variables of the surface water resources. When the temperature is higher (or lower) than its normal, the surface potential evaporation tends to increase (or decrease), the surface runoff and the soil moisture content tend to decrease (or increase). Especially the variables of the surface water resources in the west part of Northeast China are the most sensitive to the temperature variation in summer and in autumn. And in the southeast part of Northeast China, the influence of the temperature on the surface water resources is smaller relatively.The variables of the surface water resources in Northeast China have the very closely relations with the precipitation. When the precipitation is more (or less) than its average, the surface potential evaporation tends to decrease (or increase), the surface runoff and the soil moisture content tend to increase (or decrease) greatly. The correlation coefficients can reach 0.70 to 0.98, far exceeding 99.9% significance level. The influence of the precipitation on the surface runoff is the biggest. In summer, when the precipitation increases or decreases 20%, the surface runoff can even increases or decreases 55% to 60% in Northeast China. The statistical evaluation models about the influence of the temperature and the precipitation on the variables of the surface water resources established in this study have the very good capability of prediction and assessment. In summer the variations of the variables of the surface water resources are mainly controlled by the precipitation, but the influence of the temperature on the variables of the surface water resources in spring is also important. The responses of the surface runoff to the simultaneous variation of the precipitation and the temperature are also the most significant. When the precipitation and the temperature increase (or decrease) 10% and 1℃, the surface runoff can increase (or decrease) 25% to 30%, i.e. "the smaller climatic fluctuation" can result in a bigger change in the surface water resources in Northeast China.
  • Carbon Storage of Forest Vegetation and Its Relationship with Climatic Factors
    ZHAO Min, ZHOU Guang-Sheng
    2004, 24(1): 50-54. https://doi.org/10.13249/j.cnki.sgs.2004.01.50
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    Forests are major vegetation types in terrestrial ecosystem and play a key role not only because they account for a greater part of the carbon exchange between the atmosphere and terrestrial biosphere than any other ecosystem type, but also because they can mitigate carbon dioxide emission under the background of global change, and accurately estimating forest carbon storage is increasingly gaining global attention. In terms of the fourth national forest inventory data (1989-1993), forest vegetation carbon storage and carbon density in China are estimated by the relationships between stand biomass and volume for different forest types. The results shows that total forest vegetation carbon storage and average carbon density in China are 3778.1Tg(1Tg = 1012g)and 41.32 Mg/hm2(1 Mg = 106 g), respectively. Forest vegetation carbon is not distributed evenly among provinces in China: more than half of the carbon is stocked in northeastern and southwestern China. Carbon storage of forest vegetation in China is about 1.1% of the global vegetation, and forest carbon density is lower than the world's average, the major reason is that the area of pre-mature forests in China occupies more than 80% of Chinese forests. It suggests that Chinese forests have the large potential to fix carbon. In addition, based on linear multi-regression of forest carbon storage model and standard regressive coefficient methods, the relationship between carbon storage of forest vegetation in China and climatic factors including temperature and precipitation is developed:Yc=2.004Xp-2.809Xt+1.805. The regressive coefficient of annual precipitation (Xp) and mean annual temperature (Xt) show that forest vegetation carbon storage will decrease with climate warming, but it will increase with the increase of precipitation. According to factor analysis method, the contribution of climatic factors to forest vegetation carbon storage is calculated, the contribution of annual precipitation is 2.363, and that of mean annual temperature 3.227, it indicates that the effect of temperature on forest carbon storage is larger than that of precipitation,and global warming may seriously affects the forest carbon storage in China. The study may be helpful not only to provide a method for estimating carbon storage of forest vegetation using systematic and continuously forest inventory data in China, but also to improve understanding the relationship between climatic factors and carbon storage of forest vegetation.
  • Analysis on Spatial-Temporal Characteristics and Driving Factors of Woodland Change in the Northeastern China Based on 3S Technology
    XU Xin-Liang, LIU Ji-Yuan, ZHUANG Da-Fang, ZHANG Shu-Wen
    2004, 24(1): 55-60. https://doi.org/10.13249/j.cnki.sgs.2004.01.55
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    The development of 3S technology that including RS(Remote Sensing), GIS(Geographic Information System) and GPS(Global Position System) provides an effective method for woodland resources investigation and analysis of spatial-temporal characteristics. This article analyzed the woodland changes from 1985, 1995 and 2000 LANDSAT TM images based on 3S technology. The authors studied the spatial-temporal characteristics of woodland change in the northeastern China according to dynamic degree model and time series analysis. It is found that during 15 years from 1985 to 2000, the great changes of woodland had taken place in the northeastern China. The rate of forest decrease during the period of 1995-2000 is less than that of previous period, the area of forest increased 353 thousand ha from 1995 to 2000. But the scope and depth of woodland change during the period of 1995-2000 exceeded that of previous period. This phenomenon was represented in Da Higgan Mountains region. From the point of view of spatial patterns, the change rate of woodland in piedmont such as Da Higgan Mountains, Xiao Higgan Mountains, Changbai Mountains was higher than that of other regions. On the other hand, the authors analyzed the driving factors that caused above process in different regions.
  • Modern Desertification Process in Ejina Oasis and Its Dynamic Mechanism
    LI Sen, LI Fan, SUN Wu, LI Bao-Sheng
    2004, 24(1): 61-67. https://doi.org/10.13249/j.cnki.sgs.2004.01.61
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    The Ejina Oasis is a famous natural oasis that develops on inland river delta of the lower reaches of the Heihe River. Since the 1950s, its rapid desertification causes a decrease in the oasis area and degradation in ecological environment. The present desertification as a complicated dynamic process of the earth surface is characterized by the several degradation processes such as in water, vegetation, soil and biodiversity. In the process of desertification, the Ejina natural oasis has degraded systematically in the surface features, vegetation and the land biological productivity, and the area of the Ejina natural oasis has decreased to 3070 km2 from 3908 km2 in the 1960s, reduced by 21.44%. The reason for these is that many variables play a comprehensive role in the desertification of the Ejina Oasis, which include a warming and drying tendency in climate, strong erosion force, irrational utilization of water and land resources in the middle and upper reaches, and the three popular typical human activities of over cultivation, overgrazing and overhacking in the oasis. Based on the method of rotated PCA, the first tow factors respectively account for 59.276% and 28.083%, which implies that the modern desertification is due to many factors, but the factor of human activities in and outside the oasis leads the first. The warming and drying tendency in regional climate and the strong erosion force are the internal driving forces, but the excessive human activities in and outside the oasis is the external driving force. From analysis above, the paper finally come to a conclusion that the modern desertification mechanism is made of three ones: regional mechanism results from coupling of human and natural factors in temporal and spatial, which controls the changes of ecological environment and the humanitic and historical changes in the Ejina Oasis; dynamic mechanism from mutual interaction among driving factors, which is in chain reactions and becomes the direct driving force of the desertification; and the positive and negative feedback, which be of vicious circle, focus on the relation between the driving forces and the desertification.
  • Analysis of Roles of Human Activities in Land Desertification in Arid Area of Northwest China
    LI Xiang-Yun, WANG Li-Xin, ZHANG Yu-Shu, ZHANG Hong-Qi
    2004, 24(1): 68-75. https://doi.org/10.13249/j.cnki.sgs.2004.01.68
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    The important conflict in arid area is the negative effect of human activities to environment for which the land desertification is taken in the leading position. Based on the characteristics of arid area and the concept of land desertification given by "United Nations Convention to Combat Desertification in Those Countries Experiencing Serious Drought and /or Desertification, Particularly in Africa, 1994, 10 in Paris", the conceptual model of desertification causes is built. In this model, the natural factors include geology, climate, hydrology, vegetation and land and the human operates on these natural factors. The different natural factors have different ways of human activities. Through the analysis on specialties and meaning of human activities, the human activities are thought as consisting of driving and manner factors. Further, the manners and driving force of human activities on land desertification are studied. According to some criterions, an indexes system which shows the human activity effect on desertification in arid area is designed. The most of indexes are quantitative in this system and it can indicate the dynamic changes. Thus, the indexes system can supply the basis for the quantifying study of human effect on desertification.
  • Evolution and Developing Trend of the Jiujiang River Course of the Yangtze River in Recent Forty Years
    LI Mao-Tian, YU Xia, CHEN Zhong-Yuan
    2004, 24(1): 76-82. https://doi.org/10.13249/j.cnki.sgs.2004.01.76
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    Jiujiang is one of the best import business and tour center in Jiangxi Province. However, more and more flood disasters from the Yangtze River have been occurred since the last century. The Jiujiang River course evolution has huge impact on flood discharge, shipping and the sustainable development of Jiujiang City. This thesis adopts DEM (Digital Elevation Model) and GIS (Geographic Information System) technology, and rationally simulates the Jiujiang River course evolution in recent forty years on the basis of the Yangtze River Lower Reaches Relief Map in 1963,1972 and 2002 (map scale is 1∶10000). It quantitatively expresses spacial-temporal distribution of riverbed erosion-deposition such as cross section, vertical section, isobaths and erosion-deposition volume. From 1963 to 1972, the Jiujiang River course was generally characterized by deposition, and the total deposition volume was 6.505×106m3, average annual deposition load was 0.65×106 m3/a, and the main deposition area is located in the south bank area of upper-middle course and the middle area of lower course, the main erosion area is situated in the north bank area of the course; From 1972 to 2002, Jiujiang River course was generally characterized by erosion, total erosion volume was 20.720×106m3, average annual rate of erosion was 1.036×106 m3/a, and the main deposition area is located in the south bank area of upper course, the middle area of middle-lower course and a piece of north bank area, the main erosion area is located in north bank area of the course and the south bank area of middle-lower course; From 1963 to 2002, the Jiujiang River course was generally characterized by erosion, and the total erosion volume was 14.977×106 m3, and the main deposition area is located in the south bank area of upper course and the middle area of middle-lower course, the main erosion area is located in the the north and the south bank area of middle-lower course.The course change is relative multi-factors such as suspend sediment load and runoff load from upper reaches, geological basis and crust motions, human activities and river evolution of lower reaches. The deposition from 1963 to 1972 is directly the result of Hankou suspended sediment load increase from 1955 to 1969, which relates to deforestation activity; the erosion form 1970 to 2002 is directly the result of Hankou suspend sediment load decrease and runoff increase, which because that lots of reservoirs quickly increase in upper and middle reaches since the 1970S. In conclusion, Jiujiang course evolution is the result of the course borderline conditions, runoff, suspend sediment load and human activities. In addition, the paper gives a river evolution trend in the future, and points out the continual erosion of the south bank area in middle and lower course will bring the more pressure for preventing flood. The government should pay attention to constructing the protecting bank project, monitoring the riverbed evolution. These measurements are essential to Jiujiang City's future.
  • Sediment Budget of Yuehu Lagoon and Implications for Human Activities, Shandong Peninsula, China
    JIA Jian-Jun, GAO Shu, XUE Yun-Chuan, LI Feng-Ye
    2004, 24(1): 83-88. https://doi.org/10.13249/j.cnki.sgs.2004.01.83
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    In the latest two decades, deterioration changes of physical and ecological environment happened in Yuehu, a small inlet-lagoon system located in the eastern part of Shandong Peninsula, China, mainly due to human activities.In order to investigate the sediment dynamic behaviour of the Yuehu, measurements and sampling were undertaken to obtain data sets of tidal water levels, current velocities, suspended sediment concentrations, grain size parameters, and organic carbon contents. With these data, analysis of surficial sediment distribution, grain size trends, sediment transport rates, deposition rates, and sediment budget were carried out.The results show that the deposition rates are relatively high within the tidal basin. Based on 210Pb dating and short cores analysis, sediment flux into Yuehu Lagoon is estimated to be 1.8?104-2.3?104 t/a, whereas sediment input from the open sea, the aerosol and biological production, and the material from land is only 0.5?104-1.2?104 t/a; In another word, the total sediment flux cannot be balanced by the input. Thus, the denudation rate over the catchment basin of Yuehu Lagoon, representing a major component for the balance, was underestimated. Inferred from the aero-photos derived land use patterns, the material from land has been intensified by agricultural activities over the past several decades. Therefore, the denudation rate, must be much higher than 400 t/(km2·a). Besides land use patterns, many physical and ecological processes in Yuehu Lagoon have been altered by local inhabitant. Evolution of Yuehu Lagoon show that human being should put their development activities under the control of natural rules, otherwise un-reversible changes would happen.
  • Study on the Modern Slope Denudation Rate in the Three Gorges Reservoir Area of the Yangtze River
    HE Tai-Rong, JIANG Hong-Tao, YANG Da-Yuan, REN Zhao-Xia, LI Xu-Sheng
    2004, 24(1): 89-93. https://doi.org/10.13249/j.cnki.sgs.2004.01.89
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    In the Three Gorges Reservoir area of the Yangtze River, the main geomorphology unit is mountain, its area accounts for 78%. The uprightness altitude difference is about 2 000 m. Because there are very high mountains, very steep sloping field, human kinds' cultivation, transmigrant because of Three Gorges Project and the demand of economic development, the slope fields are exposed to very strong man-made disturbance. So the modern slope denudation process is very violent. Geomorphic measure means is a way of calculating sloping field's substance denudation mass by means of measuring the geomorphic deformation. Because of saving a great lot of middle taches, this means is very simple, practical and expediently manipulative. And its results can reflect the difference of denudation rates between slope fields which have different slope gradient. Adopting geomorphic measure means, this paper studies the modern slope denudation rates of slope fields in the Caotang River watershed. First, all slope fields can be classfied to three species according to their slope gradients. There are gentle solpe which slope gradient is less than 15?, moderate slope which slope gradient is between 15癮nd 45?, and steep slope which slope gradient is greater than 45?. Adopting the means of measuring root can confirm the denudation rate of gentle slope. Its principle is dividing the root's bare height by tree ages. And through measuring eroded channel length, width and depth on the moderate and steep slope, so their volume can be obtained. Its volume is representation of denudation mass of moderate and steep slope. To the moderate slope, we select three plots which slope gradient is 20?, 30? and 40? respectively but their vegetation coverage are similar. To the steep slope, we select two plots which are man-made through opening road and their gradient are 50? and 60? respectively. By the measuring and deducing, the results is as follows. The modern slope denudation rates of gentle slope are 3.0 mm/a and 5.0 mm/a respectively to 7?-8? and 15? slopes. The ones of moderate slope are 4.1mm/a, 5.5mm/a and 5.0mm/a respectively to 20?, 30癮nd 40? slopes. The ones of steep slope are 5.7mm/a and 8.5mm/a respectively to 50? and 60? slopes. So the modern denudation rates of three species of slope field are 4.0 mm/a, 4.9mm/a and 7.1mm/a respectively. The mean modern slope denudation rate of the Caotang River basin is 4.9 mm/a (i.e. 7902 t/km2·a), which is agree with intensely denudation degree according to national erosion standard. This result is larger than others' data. It is mainly induced by human activities in last few years. Because ecological environment is becoming worsening, so water and soil conservation is a very tough task in long time of future in the Three Gorges Reservoir Area.
  • Stability of Tidal Creek System of Tiaozini Sand Shoals in the North of Jiangsu Coast
    CHEN Jun, FENG Wei-Bing, ZHANG Ren-Shun
    2004, 24(1): 94-98. https://doi.org/10.13249/j.cnki.sgs.2004.01.94
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    Tidal creek system is one of the most particular geomorphology units in muddy flat and offshore sand shoals. This paper aims to study the tidal creek system of Tiaozini sand shoals in the north of Jiangsu coast. Through field surveying and a series of remote sensing images comparing, it details the main tidal creek system shift in recent years, such as Shishenggang, Neiwangjiachao, Xiaodengzhuanggang, Henggang, Xidagang, Dongdagang, Gaonigang. On this basis, it summarizes the development characteristics of the tidal creek system. First, every main tidal creek system has different shift distance and move rate and every part of one single tidal creek system also has different shift distance and move rate. Second, the tidal creek system in the west of Xidagang located on the center of Tiaozini sand shoals has shift period and the tidal creek system in the east of Xidagang is stable. Third, the shift style of tidal creek is sudden change and gradual change. Last, tidal creek system of sand shoal has autoconditioning action which behaves balance orientation of one single tidal creek and integrate adjusting of the whole tidal creek systems of sand shoals. This study on tidal creek system of Tiaozini sand shoals is available complementarity of the whole study of muddy flat and sand shoals tidal creek system. It also will provide scientific guidance for engineering construction, resource exploitation and so on.
  • Study on Glacial Erosion Surface of the Southeast of Qinghai-Xizang Plateau Using Cosmogenic Isotopes Dating
    XU Xiao-Bin, WANG Jian, ZHU Ji, JIANG Hong-Tao, YANG Yi-Qing
    2004, 24(1): 101-104. https://doi.org/10.13249/j.cnki.sgs.2004.01.101
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    With the development of the technique of cosmogenic isotopes dating, the formation age of glacial surface can be calculated now. Its principle is that the cosmogenic isotope concentration in the surface rock is a function of age, erosion rate and uplift rate of plateau. Samples of X8 and X9 are taken from the up-surface of glacial boulder in Kuzhao-Shangdui. Sample of X6 is taken from the up-surface of roche moutonnee in valley of the north of Mountain Tuer. The concentration of the cosmogenic isotope 10Be can be got from measure and calculation. According to field exploration, the rock surface where samples X8 and X9 are taken from is erosed about 9 cm in the exposure age t. It means that the erosion rate is about 9/t (cm·a). Then, the t (133.4 ka) can be calculated. Because having the same geographical environment, the rocke moutonnee has about the same erosion rate with the rock. The t (18.5 ka) can be calculated. The study shows that the glacier boulder was formed in 133.4 ka B.P. and the roche moutonnee was formed in 18.5 ka B.P. It can be concluded that Daocheng ice cap was about current in 133.4 ka B.P. (stage 6 of oxygen isotope of deep sea) and the glaciation in the valley occurred about in 18.5 ka B.P.(stage 2 of oxygen isotope of deep sea). The same result coming from two samples X8 and X9 taking from same glacier boulder, and the result from X6 being in concordance with field exploring show that the cosmogenic isotopes dating technique is a effective method in dating surface of landforms.
  • A Method of Data Gridding from Administration Cell to Gridding Cell
    FAN Yi-Da, SHI Pei-Jun, GU Zhi-Hui, LI Xiao-Bing
    2004, 24(1): 105-108. https://doi.org/10.13249/j.cnki.sgs.2004.01.105
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    Data gridding is a fundamental work to plot map, calculate for science and realize the spatial model. In this paper, a new method of spatial data transform from administration cell to gridding cell is presented and realized with a case of population data, supporting with ARC/INFO software. As a result, the spatial distribution of social and economic data what gridding cells express is closer to fact than what administration cells do. With the spatial resolution of gridding cells improved and the spatial scale of administration cell increased, this method of data gridding will have a more satisfied effect. Furthermore, it can be applied for data gridding from other statistics cell including remote sensing data to gridding cell.
  • Study on the Crop Water Requirements in Typical Farmlands in Western Songnen Plain
    LI Qu-Sheng, LI Xiao-Jun, LI Xiu-Jun
    2004, 24(1): 109-114. https://doi.org/10.13249/j.cnki.sgs.2004.01.109
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    Based on the FAO56 method recommended by Food and Agriculture Organization of the United Nations, the last ten-year daily meteorology data and the related observed data in field, the daily water requirements of major crops(corn, soybean and grain)from 1992 to 2001 in farmland are calculated,and analyzed systematically in Western Songnen Plain.The results show that the different crop has the different water requirement law. The peak period of corn water requirement is from the late June to early August. The daily ETc is usually more than 5 mm. The corn total ETc varied between 490 and 574 mm in last 10 years, less in wet years and more in dry years. The maximum water requirement period of soybean occurred during early and middle July, with daily water requirement usually more than 5mm, when the plants are in the late floral differentiation and early flowering stage. In the last 10 years, soybean water requirement varied between 380 mm and 440 mm with an average of 400 mm. The average sorghum water requirement is 506.8 mm with the peak period from the late June to the late July, when the plants are in the elongation stage and booting and heading stages.Employing the local effective rainfall and the calculated crop water requirement, the water deficit is confirmed. It is found that the main reason for the low yield of corn in this area is the serious water deficit in the booting and heading stages and the milk stage, in which it lacks 28% and 46.7% of the ETc respectively. The water deficit of soybean mostly is in the podsetting and podfilling stages and the mature stage. The water deficit of sorghum is mainly in the elongation stage and milking stage, with the average water deficit of 66.8mm and 65.9mm respectively. Therefore in order to increasing the crop yields in this area in the large scale, the crop water in summer and autumn should be met on the basis of the settled drought in spring by dibbling irrigation.
  • Research on the Urban Social Income-Space in Xi'an
    CHENG Li-Hui, WANG Xing-Zhong
    2004, 24(1): 115-121. https://doi.org/10.13249/j.cnki.sgs.2004.01.115
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    The study of urban social living space is the main subject of urban social geography. The present study of urban social geography in the west have turned to the evaluation of social living space, and one of its cores is the study of the spatial structure and the basic urban social living conditions as well as the distribution laws of communities. The urban social income-space constitutes one basic part of the quality of the urban social living space. This paper, firstly, generalized the relating theories of urban social income-space abroad, summarized the economic and social foundations of the differentiation of income-space, and tried to explain the impetus of the differentiation of income-space. Secondly, it is the first time that took the facts of Xi'an into consideration, tried to research the urban social income-space and its patterns comprehensively in Xi'an, meanwhile to classify the pattern of social structure of income through different social income ranks, and to evaluate the regional differences of the social income-space through the imbalance index, to summarize the spatial structures and models of the social income imbalance. Thirdly, in methodologies, it adapted the method of behavioral sampling and at the same time used the theory of the substitution between social living space and social income-space. As the urban social space of income is the indicator of the quality of the urban social living space, so the author tried to discover the quality and structure of urban social living space through summarizing the space preference surface of the urban residents in Xi'an.
  • Approach to the Protection of Drinking-water Resource in Erlongshan Reservoir
    WANG Hong
    2004, 24(1): 122-126. https://doi.org/10.13249/j.cnki.sgs.2004.01.122
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    Erlongshan Reservoir is one of the six biggest centralized surface drinking-water resources in the Liao River valley, so it is necessary to assess present water quality pollution status thoroughly, to carve up protection zone reasonably, to calculate environment capacity of reservoir water scientifically, and to enact diminishing scheme of pollutants and measures of environment protection. Based on the systematic analyses on present environmental status of Erlongshan drinking-water resource site, the paper partitions the function regions and establishes protection aim of water quality. Based on this, environmental capacity and main pollutants minifying amount of drinking-water resource site are investigated, and total amount control aim and protective countermeasures on drinking-water resource in Erlongshan Reservoir are presented in the paper. In 2005, if water quality standard III for the Erlongshan Reservoir is achieved, the capacities of COD and NH4+-N are 1 325 t/a and 1 044 t/a, respectively.