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    15 December 2003, Volume 22 Issue 6 Previous Issue    Next Issue
    Earth Surface Processes
    Sustainable basin land-use planning and its application
    GUO Huai cheng, ZHANG Zhen xing, YU Yong
    2003, 22 (6):  671-679.  doi: 10.11821/yj2003060001
    Abstract ( 1552 )   PDF (305KB) ( 1587 )   Save

    Land resource is one of the most essential natural resources Land use is the linkage between human and nature and the basis of all other economic activities Moreover, it is subject to and has serious impact on natural environment There are a variety of lakes and reservoirs in China A large population live in the basins of these lakes and reservoirs Too much sediment and heavy water pollution are the key problems to these basins, both of which are correlated closely with land use Thus it is very important to optimize basinland use structure The grey multi objective programming (GMOP)model was employed worldwide to solve many optimization problems such as economic development planning in countryside and water resource planning GMOP can reconcile multiple and often conflicting objectives, address information insufficiency and optimize system performance At the meantime,land use system is characterized by dynamic, multi objectivity and information insufficiency Therefore, GMOP is a very useful tool to optimize basin land use structure In this study, GMOP is applied to solve sustainable basin land use system planning, taking Miyun County as a case study Centered in GMOP, the Grey Multi objective Programming to Basin Land use(GMOPBLU) model was built and solved with the interactive adjustment method The GMOPBLU model has the ability to simulate the characteristics of the land use system,and is a valuable tool for achieving the harmonization of conflicts between environmental and economic objectives The Interactive Adjustment Method was also used in the study to modify the model structure and the coefficients to reflect the features and the possible diverse preference of the stakeholders and decision makers The Scenario Analysis Method was applied to interpret the planning results In the present study,GMOPBLU model was used to the sustainable land use planning in Miyun County as a case study Two types of alternatives were produced and analyzed with the help of Scenario Analysis and Interactive Adjustment Method Through comparison and analysis, the optimal alternative was selected,which can provide a scientific and reliable foundation for policy making The case study confirmed the practicability and operability of the GMOPBLU model It showed that GMOPBLU model is a useful tool for sustainable basin land use planning

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    Adjustment of land use types for desertification control and prevention:Taking Duolun County of Inner Mongolia as a typical case
    YOU Lian yuan, LU Jin fa, CHEN Hao, ZHOU Jin xing
    2003, 22 (6):  680-686.  doi: 10.11821/yj2003060002
    Abstract ( 1407 )   PDF (274KB) ( 1734 )   Save

    The formation and development of desertification always depend on two of factors: wind power and characteristics of the underlying surface Pattern sand types of land use are parts of reflections of the latter,which would certainly influence the formation and its development desertification.With Duolun County located on the Inner Mongolia Plateau in semi arid climate region as a typical representation, this paper deals with how to adjust land use types so as to improve the characteristics of the underlying surface and to control desertification The following steps are adopted for accomplishingthis objective:1) Compiling current situation map of present land use of this countyby using Landsat TM image data 2) Considering thegoal is desertification control and prevention, the following three factors like material composition of the earth surface vegetation cover degree of the earth surface and content of organic matter are used as indexes to assess ecologic safety Four grades of safety, semi safety, semi non safety and non safety are distinguished Each land use unit corresponds to a certain grade of safety, so that a map of the county level ecologic safety assessment is obtained 3)Identifying three principles for adjusting land use types:(a) collocation of macroscopic land use pattern should consist with large scale geomorphologic types or large regional geomorphologic difference, (b) ecological safety under condition of free from redesertification; and (c)actual present land use condition should well be considered 4) Adjusting land use pattern and types respectively in semi non safety and non sefety areas Land use types involved in the adjustment include farmland, grassland, open forest, sandy land, saline alkali land etc accounting for 25 8% of the county's total land area. All of the adjusted land use units are shown on the map at a scale of 1∶250,000 Besides, a primarily study on pattern of land use of this county before and after adjustment is also done

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    Spatial-temporal characteristics of land reclamation in Guanzhong region in the Qing Dynasty
    HE Fan neng, TIAN Yan yu, GE Quan sheng
    2003, 22 (6):  687-697.  doi: 10.11821/yj2003060003
    Abstract ( 1685 )   PDF (380KB) ( 1828 )   Save

    Based on numerable and valuable historical documents, spatial and temporal characteristics of land reclamation in Guanzhong region in the Qing Dynasty has been analyzed in this paper The results are: 1)As a taxing facility rather than a precise description of the farmland area, the registered farmland in historical documents of Guanzhong region in the Qing Dynasty didn't agree with the fact However, the records and their variations were spatially rational Obvious differences can be found between the farmland variations in different regions, while the variations in the same region were consistent 2)Five stages of the land reclamation in Guanzhong region during the Qing Dynasty were identified,i.e., a stage of desolation in the end of the Ming Dynasty and the beginning of the Qing Dynasty, a stage of recultivation from the 10th year of Shunzhi Emperor to the 6th year of Qianlong Emperor, a stage of expanding reclamation from the 6th year of Qianlong Emperor to the end of Xianfeng Emperor,and still another stage of desolation from the 1st year of Tongzhi Emperor to the 6th year of Guangxu Emperor, another stage of recultivation from the 6th year of Guangxu Emperor to the end of the Qing Dynasty The arable lands were reclaimed up by the time of Yongzheng and Qianlong emperors, when farmland area reached the level of the end of the Ming Dynasty The expanding reclamation during the time of the next 4 emperors (Qianlong, Jiaqing, Daoguang and Xianfeng) kept on enlarging the farmland and brought it to the "peak" level in the reign of Daoguang and Xianfeng emperors This level was not reached during the recultivation in the late Qing Dynasty 3)The land reclamation is spatially imbalanced due to environmental differences In the early stage, recultivation concentrated in the plain and tableland areas In the mid stage, expanding reclamation occurred in mountainous and hilly areas In later stage, the reclamation activities moved back to plains and tablelands As for the spatial characteristics, the plain and tableland areas with better natural conditions had a low ratio of desolation, a high ratio of recultivation and a quick process of recultivation The mountainous and hilly areas had a higher ratio of desolation, a lower ratio of recultivation and a slower recultivation, or could hardly be recultivated And the intensity of reclamation in the plain and tableland area was much higher 4)Detailed analysis on the spatial temporal characteristics of land reclamation is not only the basis of the study on farmland variation, but also an important way for the study of the variation processes of other land use types Inconsiderate employment of the registered data as the normal farmland statistics without correction will affect the reliability of the research and result in a deviation from the fact

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    A study on the issue of land consolidation and eco-security in hilly and mountainous regions of Southwest China
    YANG Qing yuan
    2003, 22 (6):  698-708.  doi: 10.11821/yj2003060004
    Abstract ( 1618 )   PDF (374KB) ( 1830 )   Save

    This essay is intended to discuss the relationship of land consolidation and eco security in hilly and mountainous regions of Southwest China based on the development trends of land consolidation at home and abroad and from the angle of target regional division of labour of land consolidation. It points out, as a typical eco friable region, to ensure the eco security is the first important target of land consolidation in the hilly and mountainous regions of Southwest China. The regional eco location is especially important because it is located in the upper reaches or headwaters of great rivers such as Changjiang, Zhujiang, Lancang rivers, etc. and it is one of the typical regions with plentiful biodiversities. Investigation and analysis indicate that not only the natural ecosystem is vulnerable in the hilly and mountainous regions of Southwest China, but also it's the role of eco protective screen is weakening.For example, the reality rate of forest coverage is far more low the theory lowest vegetation cover rate in Southwest China except Yunnan province. Thus, the regional eco security, especially the land resource security is facing numerous threats. As a natural water collecting unit and an integral land ecosystem, it is regarded the small watershed land consolidation is the representative pattern of land consolidation to ensure the safety of the regional land resources and regional eco security and realize regional sustainable development of the hilly and mountainous regions in Southwest China.The model's core concept is to allot different land consolidation countermeasures suitable for the features and ideal function of different landform positions of small watershed in order to realize different targets of land consolidation. That is to say, to arrange the macro countermeasures of land consolidation according to the special characteristics of the land ecosystem of small watershed, such as to adjust the land use structure, and allocate micro countermeasures of different standard according to the features of different landform positions, such as to close hillside to facilitate afforestation in the watershed regions, to return farmland to forest and grassland on steep slopes exceeding 25 degrees,to build terraced fields in areas where the slope ranges from 8~25 degrees, and to develop flood land.

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    Hydrological similarity of catchments based on topography
    KONG Fan zhe, RUI Xiao fang
    2003, 22 (6):  709-715.  doi: 10.11821/yj2003060005
    Abstract ( 1652 )   PDF (269KB) ( 2688 )   Save

    The topographic index ln( a /tan β ) is an important parameter of many physically based hydrological models In terms of a DEM, a is the cumulative upslope area draining through per contour length to a pixel, which reflects the tendency of water to accumulate at any point in the catchment, tanβ is the local slope angle of the cell, which reflects the tendency for gravitational forces to move that water downslide Catchment topography generally have a major control overflow pathways for surface flow processes and an important effect on parttern of likely water accumulation in the catchment The catchment's topography may be summarised by the distribution of the index values The topographic index may be used as an index of hydrological simularity All points with the same value of the index are assumed to respond in a hydrologically similar way Frequency distribution of the index is used in TOPMODEL for simulating hydrographs It may be expected that the catchments with the same frequency distribution of the topographic index have hydrological similarity A simple algorithm for the calculation of topographic index ln( a /tan β ) is used, In the algorithm, a and tan β of each cell is extracted separately ,and the cells, whose slope is zero, are treated specially so that ln( a /tan β ) can be calculated The frequency distribution of the topographic index ln( a /tan β ) is obtained It can be found that Xiangxihe catchment and Yanduhe catchment have hydrological similarity The frequency distribution of the index and estimated TOPMODEL parameters of Xiangxihe catchment are used to simulate the hydrographs of Yanduhe catchment and good results are obtained

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    Study on several important problems about urban flood-control construction of Changsha city
    MAO De hua, XIA Jun, GONG Chong hui
    2003, 22 (6):  716-724.  doi: 10.11821/yj2003060006
    Abstract ( 1309 )   PDF (143KB) ( 2049 )   Save

    Seveal problems about urban flood control construction of Changsha city, akey important flood control city in China, are studied These issues include the establishment of flood control standard, flood level designing and height determination of floodwalls; construction policy and program; entire flood control power construction; harmonious development among flood control installations construction, infrastructure construction and urban landscape construction,etc The designed flood recurrence interval (flood control standard) in Changsha city is 100a The establishment of flood level designing should take the following aspects into consideration: high standard floods in Xiangjiang River flowing through Changsha city and its branches as well as Dongting Lake have never met with each other nor the occurrence of the same frequency flood; relation is not the major evidence of flood design;and the amplitude of setup of flood of the South Dongting Lake is a unsteady influencing factor and the reduction of channel storage is a steady influencing factor of flood level in Changsha city Flood control levee altitude is higher than the real demand of Changsha city,which reduces the levee steadiness, and causes ineffective investment and influence on the urban landscape The flood control projects must be constructed step by step,firstly excluding the dangerous factors and then reinforcing levee and therefore improving the entire flood control power, also be harmonized relations with the construction of urban infrastructure and the construction of urban landscape

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    Dynamic change of forest resources in Guizhou province
    ZHANG Bai ping, NIE Chao jun, ZHU Jun, YAO Yong hui, MO Shen guo, LUO Yang, CEN Gang
    2003, 22 (6):  725-732.  doi: 10.11821/yj2003060007
    Abstract ( 1526 )   PDF (313KB) ( 1953 )   Save

    Located in the upper reaches of the Yangtze River and the Zhujiang River, Guizhou Province is one of the provinces carrying out the National Natural Forest Conservation Project It is also one of the major gene pool areas and one of the famous producing areas of medicinal materials in China The development and conservation of forest resources is not only significant for protecting environment and biological diversity but also important to the economic development of Guizhou and even the middle and lower reaches of the Yangtze River and the Zhujiang River According to forest data collected in 1979, 1984, 1990, 1995, and 2000 by the Institute of Forestry Survey and Design of Guizhou Province, this paper provides detailed information about the dynamic changes of forest resources and concisely explains the factors arousing these changes In general, Guizhou's forest resources decreased rapidly from the late 1970s to the late 1980s; but since 1990, they have steadily increased (1)The forestry land keeps almost unchanged since 1984; the major types of forests expanded considerably, especially the protective forest, economic forest and specific forest; timber forest increased with some fluctuation, while sparse forest and non forest land decreased (2) The growing stock of living forests has had a trend of increase since 1984; the growing stock of major types of forests decreased from 1979 to 1990, but began to increase thereafter (3) The area and growing stock of planted forests increased rapidly; natural forests also showed a trend of expanding, and their growing stock began to rise after 1990 (4) Young age forests grew quickly both in area and in growing stock; mid age and over mature forests showed a trend of decreasing in area and growing stock from 1979-1990 but a trend of increasing since 1990 The percentage of young age forests decreased, while that of mid age and mature and over mature forests increased (5) As for the composition of forest resources, the proportion of timber and fuel forests has lowered, while that of shelter, specific and economic forests increased (6)Since 1990, thanks to the implementation of several ecological and sustainable development projects in Guizhou, its forest resources have grown enormously, and the ecology and environment greatly improved

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    Spatial pattern of the fragile karst environment in southwest Guizhou province
    LAN An jun, ZHANG Bai ping, XIONG Kang ning, AN Yu lun
    2003, 22 (6):  733-741.  doi: 10.11821/yj2003060008
    Abstract ( 1757 )   PDF (424KB) ( 2862 )   Save

    The karst areas in Southwest China constitute one of four fragile eco zones in China Southwest Guizhou, characterized by typical karst landscape and environment, is one of the major regions for rehabilitation in West China For a long time, human activities have led to serious rock desertification, soil erosion and forest ecosystem degradation in the study region, and have exerted adverse effect on regional economic development and ecology This paper analyzes ecological degradation, its spatial pattern and the related driving factors in southwest Guizhou province Rock desertification and soil erosion are the most serious ecological problems in southwest Guizhou, closely related to forest and soil degradation The karst landform pattern generally controls the ecological pattern, while population pressure and the resulting unreasonable human activities serve as the most powerful driving forces for environmental degradation Consequently, the regional man land contradiction is responsible for the deterioration of karst environment, with man as the core of the contradiction The rehabilitation of the deteriorating environment consists of two aspects,i.e., stopping human destructive activities and carrying out improvement measures Based on GIS analysis, the degree of ecological fragility ( I ) is given according to the equation: I=I 1 + I 2 -I 3 where I 1 is the ratio of rock desertified area, I 2 the ratio of soil eroded area, and I 3 the forest coverage The study region is divided into four sub regions in terms of the value of I: one extremely fragile sub region ( I =64), one seriously fragile sub region ( I =51), and two moderately fragile sub regions ( I =27, 26, respectively) This provides a framework for management of regional ecology and environment in southwest Guizhou

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    Restoration and reconstruction of the forest vegetation in the Mufushan-Yanziji Mountains,Nanjing
    ZHAO Qing, DING Deng shan, YAN Chuan hai
    2003, 22 (6):  742-750.  doi: 10.11821/yj2003060009
    Abstract ( 1554 )   PDF (299KB) ( 2276 )   Save

    Based on field survey, AutoCAD technology, principles and methods of vegetation ecology and restoration ecology, the following problems about restoration and reconstruction of the forest vegetation of Mufushan Yanziji Mountains in Nanjing are studied: (1) According to the principle and system of Chinese Vegetation , the vegetation of Mu Yan Mts is classified, including 3 vegetation type groups, 5 vegetation types, 5 vegetation subtypes, 8 formation groups and 12 formations The 12 formations are: Pinus thunbergii forest, Platycladus orientalis forest, Pinus massoniana forest, Quercus fabri forest, Quercus acutissima forest, Broussonetia papyrifera forest, Celtis sinensis forest, Pteroceltis tatarinowii forest, Robinia pseudoacacia forest, Phyllostachy pubescens forest, Celtis sinensis + Paliurus hemsleyana + Spirea chinensis shrub, and Broussonetia papyrifera shrub (2) The map (1:5000) of the vegetation formations of Mu Yan Mts is compiled, and the areas of the formations are calculated (3) There are mainly 10 forest formations in Nanjing, i e , Cyclobalanopsis glacuca + Quercus variabilis forest, Liquidambar formosana forest, Quercus fabri forest, Quercus variabilis forest, Quercus acutissima forest, Pistacia chinensis + Dalbergia hupeana forest, Celtis sinensis + Broussonetia papyrifera forest, Robinia pseudoacacia forest, Pinus massoniana forest and Pinus thunbergii forest The successional relationships among the 10 formations are analyzed, and the secondary succession model of the forest vegetation in Nanjing is established (4)According to the above research results, the measures for restoration and reconstruction of the forest vegetation of Mu Yan Mt are proposed, the changes of the vegetation type composition are predicted after the measures are put into effect, and the restoration and reconstruction planning map (1:5000) of the vegetation types of Mu Yan Mt is made

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    Housings' spatial distribution and residents' preference on housing location in Beijing
    ZHANG Wen zhong, LIU Wang, LI Ye jin
    2003, 22 (6):  751-759.  doi: 10.11821/yj2003060010
    Abstract ( 1357 )   PDF (334KB) ( 2634 )   Save

    With the development and improvement of market system of real estate, urban residents' housing consumption for individual use has become the main body of real estate market So, their individual characteristics have direct influences on their housing purchases and location selections Based on the analysis of the actual condition of housings' spatial distribution in Beijing and the questionnaires on local residents' selection of housing location, this paper mainly discusses three issues: 1) basic characteristics of housings' spatial distribution; 2) local residents' preference on housing location; and 3) interrelations between residents' individual properties and their preference on housing location, etc Three conclusions are followed: Firstly, since the 1990s, the construction of residence communities has been speeding up and the scale enlarging There are two features in housing distribution: one is that the housing construction beyond the 3rd Ring Road assumes a fast development whereas that within the 3rd Ring Road has come to a slowdown or even a stagnancy The other is that housing distribution assumes a circle layer structure toward outskirts of the city, the northern part of which boasts a faster housing development than the southern Secondly, according to local residents' preference on housing location, those housings between the 3rd Ring Road and the 4th Ring Road are still in the first choices of local residents In terms of orientation, north, northeast and northwest gain more attentions Thirdly, revealed by a foreign research, differences in residents' individual social characteristics may result in differences in selecting housing location However, after a research on the relations between local residents' individual social characteristics and their preference on housing location, we find that there lacks a clear cut relationship between them while there is a certain similarity in preference on housing location among those people with different income levels, different occupations and different family structures

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    The characteristics of peri-urbanization region:a case study of Dongguan Municipality in Guangdong province
    ZHENG Yan ting, LIU Sheng he, CHEN Tian
    2003, 22 (6):  760-768.  doi: 10.11821/yj2003060011
    Abstract ( 1642 )   PDF (463KB) ( 3562 )   Save

    Since reform and open up, owing to the influx of foreign capitals, the world wide manufacturing shift and the development of TVEs, a kind of area has been formed and developed in some post rural areas of the Yangze River Delta and Pearl River Delta. It's a transitional zone where urban and rural land use interlocked and economic and social structure changed rapidly. Based on literature review, this paper defines it as peri urban and puts forward a complete index system, in terms of structure, change in gross amount, landscape and administrative features. Then taking the case of Dongguan Municipality, the characters and the problems of the peri urban area are analyzed, in terms of economic conditions, industry, population, employment, land use and administrative system. Dongguan Municipality, characterized by rapid economic growth, mass entry of immigration, rapid development of non agricultural activities, expansion and interlock of non agricultural land use and rural administrative system,has thus embryonically formed a peri urban area. According to international experience Dongguan is in a crossroad. So we should clearly consider its advantages and regulate its social, economic, and urban development strategy for sustainable development and evolvement to late model urbanization.

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    The comparison of spatial characteristics in urban landuse growth among the central and sub-cities in Shanghai Region
    LI Xiao wen, FANG Jing yun, PIAO Shi long
    2003, 22 (6):  769-779.  doi: 10.11821/yj2003060012
    Abstract ( 1493 )   PDF (612KB) ( 2603 )   Save

    By using multi temporal remotely sensed data of TM & ETM, the spatial behavior of urban growth in Shanghai Region was studied by establishing and applying the urbanization metrics (i e UPI & UII) in GIS buffering analysis, which was also used in comparing and analysing the spatio temporal changes in urban landuse growth of central and sub cities of Shanghai The results showed that: 1) Being without influence of large scale geomorphic heterogeneity except geo contrast between the ocean and terrene, the spatial behavior of urban landuse expanding is largely regulated by the distance to the Shanghai central city (i e CBD) Urban landuse expanding exhibited the distinctive spatial characteristics in different periods, and the activity & spatial distribution of urban expanding circle also showed their unique traits in different periods. 2) The urban landuse growth presented obvious trends in directional variation The overall directional variation within 10 km to the CBD is dominated by spatial heterogeneity in central urban landuse growth, whereas the distribution and the variation in growth rate of sub cities play the key role in overall directional heterogeneity beyond 10 km to the CBD, and the small scale geomorphic variation from the spatial pattern of rivers and channels also shows its contribution. 3) Shanghai central city keeps overwhelming preponderance to the sub cities in magnitude, intensity and potential of urban landuse growth Affected by the location and sociao economic condition, the main sub cities performed differently in their spatial behavior of urban landuse growth individually, and thus can be classified into four categories according to their performance in urban landuse expanding (i e Standard, Passive, Steady and Irregular types)

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    Studies on recent built-up land-cover change of urban area in the Pearl River Delta
    HU Wei ping, YANG Guo qing, Wu Zhi feng, HE Jian bang
    2003, 22 (6):  780-788.  doi: 10.11821/yj2003060013
    Abstract ( 1585 )   PDF (344KB) ( 1859 )   Save

    Urban development is significant during the past two decades in the Pearl River Delta(PRD) Many researchers have studied urban development of partial areas in the PRD from different viewpoints recently, but nobody sdudied the urban land cover change of the PRD from the integrated point of view This paper exemines the built up land cover change of the urban area of the whole Pearl River Delta from 1988 to 1998 TM imageries taken from 1988 to 1998 were used to get the built up area thematic information,and a spatial database of the urban areas in the PRD was set up aided by Arc/Info 8 02 We selected the Maximum Likelihood Classifier(MLC) to extract urban built up area themeatic information The spatial features of built up land cover change in urban area were analysed in detail Firstly, the inner circle and outer circle spatial structure of built up land cover distribution kept relatively stable during the study period The total built up area in inner circle is 83 46% of the whole built up area in the PRD in 1988, and it is 84 18% in 1998 Secondly, the core oriented development and transportation oriented development are remarkble The core urban area such as the Guangzhou Foshan metropolis and Hongkong Shengzhen metropolis developed rapidly The urban area along the lines of the 107 national highway,Guangzhou Shenzhen railway and the Guangzhou Zhuhai section of the 105 national highway grows evidently Thirdly, the spatial distribution of the growth amount of built up area differs from the spatial distribution of the growth speed of the built up area greatly Fourthly, the spatial distribution of the average growth intensity index per year(AGIIPY) was analysed, the results show the high value of the AGIIPY distribution are core oriented and trunk road oriented The main driving factors of urban built up land cover change in the PRD were generally discussed The result shows the correlativity between urban built up area and gross output value of industry in the PRD is notable The urban built up area and the total population also have remarkble correlative relationship The other factors such as transportaion conditions,regional economy and administration are very important for urban development

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    Analysis on urban land use sprawl by using GIS:the case of Shijiazhuang City,China
    XIAO Jie ying, GE Jing feng, SHEN Yan jun, CHANG Chun ping, LIANG Yan qing
    2003, 22 (6):  789-798.  doi: 10.11821/yj2003060014
    Abstract ( 1907 )   PDF (399KB) ( 2452 )   Save

    In this paper, the multi temporal maps of Shijiazhuang city in 1934, 1947, 1981, 1991, and 2001 are inputted into the GIS software, MapInfo5 0, to analyze the temporal and spatial distribution of urban sprawl during the last 67 years It is found, temporally, that the course of land use sprawl of Shijiazhuang can be divided into 4 stages, i.e.,slow growing stage (1934-1950), rapid developing stage (1950-1955), crawling increase stage (1955-1981),and speedy rising up stage (1981-2001) Spatially, urban sprawl can be categorized into 3 typical patterns: the pattern of urban sprawl by special purpose in special times, such as war period during 1934-1947; the pattern of urban sprawl intervened violently by political factors, such as in the years of cultural revolution; and the pattern of normal growth in recent two decades In different development stages, the maximum annual relative sprawl rate for the griding unit of 1km×1km varies in a large range of 2 95-10 1% During 1934-1947, the mean annual relative sprawl rate is 1 9%, with the maximum of 7 2% distributed in the west of the city for military use; during 1947-1981, the mean value is just 1 32%, with the maximum of 2 95%, and distributed mainly in the northeast as industrial area and the west side as administration use; during 1981-1991, however, the mean sprawl rate is 3%, and the maximum rises up to 9 75%, mainly distributed in the southeast of the city and the northern part of Shijiazhuang Taiyuan Railway; in the latest decade, 1991-2001, the mean sprawl rate suddenly increased to 7 81%, and the maximum also reached 10 1%, the sprawl areas with a high speed of more than 6 8% are mainly distributed in the northwest and southwest for residential use and the so called high tech developing zone at the east The main driving factors of urban sprawl are population, transportation, social and economic circumstance, and so on The population and transportation conditions are the most important factors The urban environment was affected by the rapid urban land use change;it will be an important problem in the future

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    The crop distribution of Yellow River Delta using remote sensing method
    PAN Zhi qiang, LIU Gao huan, ZHOU Cheng hu
    2003, 22 (6):  799-806.  doi: 10.11821/yj2003060015
    Abstract ( 1588 )   PDF (409KB) ( 2271 )   Save

    Agriculture plays an important and basic role in the Yellow River Delta It is quite essential for agricultural managers to understand the information on allocation of crop production as a whole The traditional way of obtaining the information on crop allocation is the statistical or investigation method Compares to the traditional method, the remote sensing techniques have the advantages of quickness, precision and visualization in providing the information of crop production There are also difficulties for remote sensing to discriminate different crop areas because all the crops have similar spectrum curves on the remote sensing images To solve this problem, in this paper three remote sensing images of the Yellow River Delta at different stages of a year are used, and three NDVI maps are obtained based on the images respectively which are combined into one NDVI image Because the NDVI varieties of crops planted in different fields are different during the year, there will be different regions which show different colors on the combined image Samples from different color regions are analysed and it can be confirmed that the red area in the combined image is the region where winter wheat, corn and soybean are planted, the purple area is the region where cotton, spring corn and other crops are planted, the light blue area is the region where rice is planted and the light green area is the region where forest and grass are planted According to the characteristics of NDVI in different color areas the combined NDVI image is classified using unsupervised classification method and supervised classification method Finally the classification result is analysed Through this research we can understand the crop planting system of the Yellow River Delta macroscopically, and can provide service for the sustainable development of agriculture in the Yellow River Delta

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