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    Landuse Change Mechanism in Shenzhen City
    SHI Pei jun, CHEN Jin, PAN Yao zhong
    Acta Geographica Sinica    2000, 67 (2): 151-160.   doi: 10.11821/xb200002003
    Abstract1464)      PDF (217KB)(2377)      
    Based on remote sensing images in 1980, 1988 and 1994, the Shenzhen citi’s land use was conducted through methods of maximum like and probabilistie relaxation. Which revealed the city’s spatial process during 15 years. The conclusions may be distingnished as follows: (1) The results of the detection are reasonable and it is feasibility to calculate the transfer matrix of landuse to show spatial pattern of landuse distribution as unit of image pixel. (2) The main characteristics of the city’s landuse change are the obvious reduction of the existing farm and orchard lands and subsequent rapid increase of urban landuse along the coast and several major roads which are controlled by the opening policies of establishing the special economic zone in this city. (3) The characteristics of the city’s landuse changes are mainly demonstrated as follows: The urban landuse increases rapidly at the expense of occupying great amounts of farmland, showing the patterns of belt distribution along the main transportation lines and of spreading outside the Special Economic Zone. In the primary landuse such as farmland and woodland, etc, the tendency from the lower benefit landuse pattern transforming to the higher benefit one has taken place due to the influence of urbanization. Furthermore, the city’s landuse changes also demonstrate the characteristics of bare land enlargement and farmland split up, which is one of important factors recently led to serious soil erosion and no point source pollution in the city. (4) Under the policy of the special economic region produced by the central goverment of China, the external driving forces of landuse changes in Shenzhen City are the rapid growth of population, foreign investment and development of the tertiary industry which was based upon the real estate. The counter force of landuse changes in Shenzhen City are the transportation issue, topography, landuse patterns, the most importent factor is the transportation.
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    Cited: Baidu(2206)
    Mono-window Algorithm for Retrieving Land Surface Temperature from Landsat TM6 data
    Qin Zhi hao, Zhang Ming hua, Arnon Karnieli, Pedro Berliner
    Acta Geographica Sinica    2001, 68 (4): 456-466.   doi: 10.11821/xb200104009
    Abstract1239)      PDF (279KB)(1002)      
    Landsat TM data has a thermal band (TM6) to monitor the thermal radiance and surface temperature of the earth. For a long time, retrieval of surface temperature from TM6 data is done through the method called atmospheric correction, which requires the estimate of atmospheric thermal radiance and absorption. The computation is complicated and the accuracy is strongly subjected to the estimate, hence has few applications in real world. In this paper, a new method with simple computation and high accuracy is developed on the basis of thermal radiance transfer equation of the ground. The impacts of both atmosphere and the emitted ground on the thermal radiance transfer of the ground are directly involved into the proposed algorithm, which requires 3 essential parameters for the retrieval: emissivity, transmittance and atmospheric average temperature. Validation indicates that the accuracy of the algorithm is high up to <0.4℃ for the estimate of the essential parameters with no errors and <1.1℃ for the estimate moderate errors. Since the method is applicable for the remote sensing data with only one thermal band, it has been termed as mono window algorithm.
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    Cited: Baidu(2070)
    Wu Bihu, Tang Junya, Huang Anmin,Zhao Rong, Qiu Fudong, Fang Fang
    Acta Geographica Sinica    1997, 64 (2): 97-103.   doi: 10.11821/xb199702001
    Abstract1090)      PDF (127KB)(2329)      
    Three thousand three hundred and ninety four questionnaires were received respectively from Shanghai, Xi’an, Chengdu and Changchun during 1992~1995. Data about destination choice behavior of the respondents in the 4 cities were collected and dealed with computer aided techniques. Traveling behaviors discussed in this paper include both tourists and leisurers in the population of urban areas. An average visited rate was used to demonstrate distance delay of destination utilities by urban residents, which consisted of that of the first five favorite destinations in urban area (0~15 km from origin), suburban area (15 km~50 km), and belts around city with radii of 50 km~500 km, 500 km~1500 km and that more than 1500 km. Destinations situated in urban area have a mean visited rate of 91.2%, suburban area has 59.5%, belt around city with radii of 50 km~500 km reaches 52.1%, 500 km~1500 km reacheds 29.9%, and that more than 1500 km 14.9%. Taking the total market fragmentation of a city as 100, more than 80 of it distributed within a distance less than 500 km from the city. Total destination choice behavior beyond 500 km of a city was biased toward other cities and sites near them, but not destinations of scenic spots far away from them. And those cities which were more favorite by urban residents often located along coastal belts, including Dalian, Qinhuangdao, Beijing, Tianjin, the medium sized cities in the Shandong Peninsular, the cities in the Changjiang Delta, Amoy, Shenzhen, Canton and Haikou. The main destination choice behavior from a city by those non local residents dominantly occurs in a range of 250 km away from the city. There was a distinguished difference between destination choice behavior and attitude. Most of the respondents had a strong preference to destinations located far away from metropolitan area with beautiful scenery and clear air and water in their attitude for recreation , while most of them actually had a behavior of traveling more often to destinations in the metropolitan. Two factors caused above phenomena of contradictions: various natures of the destinations will change the actual visited rate of it; determinants, besides attitude, especially under the circumstances around tourists, would influence destination choice behavior greatly. Characteristics of tourists and leisurers also had important impact on destination choice behavior. A difference existed between male and female respondents in their emissiveness, male respondents occupied a 55.92 percent of the total, while female occupied 44.08 percent. Male and female respondents had slight different preferences to destination types. Age groups determined destination choice behavior. Site of scenic spots far away from the metropolis means more difficulties for tourists, and it is not surprised that young people had more preferences to them than those who were older. At the same time, elders appeared more interested in sites with rich historic and cultural contents than young persons. Occupations to a certain extent determined income and destination choice behavior. Respondents of some vocations with higher income had more opportunities to visit more destinations. Education level influenced behavior of tourists. A case study was given about Xi’an Tablet Forest and Huashan Mountain (the West Sacred Mt.) by the authors to tell a detail story. The Xi’an Tablet Forest is a historic site in the former capital of ancient China, while Huashan Mt. is a physical landscape with steep cliff and overhanging rocks. Tourists at Tablet Forest were more educated than those at Huashan Mt.
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    Cited: Baidu(1269)
    Li Xiubin
    Acta Geographica Sinica    1996, 63 (6): 553-558.   doi: 10.11821/xb199606009
    Abstract1359)      PDF (276KB)(4535)      
    Land use and land cover change has aroused increasing attention of scientists worldwide since1990.Recognizing the importance of this change to other global environmental change and sustainable development issues,the International Geosphere-Biosphere ProgrammeIGBP)and the HumanDimensions of Global Environmental Change ProgrammeHDP)initiated a joint core projectLand Use and Land Cover Change(LUCC)and published a Science/Research Plan for the project.To promote the national LUCC projects,the paper presents a general review on the basic concepts,background,and Progress on the metnodologies of international LUCC researches.Land use/land cover is not a new research domain but is given new meanings and research contents in the context of global environmental change.Based on the definition of land cover given bythe IGBP/HDP and other international institutions,the author proposes a new translated term ofland cover in Chinese that matches the definition closely.This will avoid misunderstanding of thedomestic LUCC projects at early stages.Land cover changes refer to conversion and modification of vegetation,changes on biodiversity,soil quality,runoff,erosion,sedimentation and land productivity.International researches onLUCC involve:1)influence of LUCC on systematic global enviromental changes like biogeochemicalcircles and climatic variation,and cumulative global environmental changes like eforestation,biodiversity reduction and land degradation;2)response of LUCC to global environmental changes;3)LUCC and sustainable development including the sustainability of different land uses.The fundamental scientific issue of LUCC research is the dynamics of land use and coverchanges,which is extremely significant to the prediction of the global environmental change in thenext 50 to 100 years.The modedling of causes-use-cover system is challenge because of its inherentcomplexity.An integrated approach to the modeling is necessary that combines:1)large-scale onsite case study approach to land use dynamics;2)direct observation and measurement of land coverchange by using remote sensing images;and 3)regional and global modeling of economic processesrelated to LUCC.
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    Cited: Baidu(1221)
    Causes of Sand-stormy Weather in Northern China and Contral Measures
    YE Du zheng, CHOU Ji fan, LIU Ji yuan, ZHANG Zeng xiang, WANG Yi mou, ZHOU Zi jiang, JU Hong bo, HUANG Hong qian
    Acta Geographica Sinica    2000, 67 (5): 513-521.   doi: 10.11821/xb200005001
    Abstract695)      PDF (472KB)(824)      
    In northern China, the number of days with sand stormy weather has been decreasing in the past 40 years, but in the spring of 2000, an unprecedented heavy sand stormy weather with high frequency took place, which exerts adverse effect on traffic, environmental management and people’s daily life and work. Especially, it brought direct damage to Beijing, Tianjin and their neighbouring areas, which has aroused even more extensive concern of personages of various circles. Therefore, the reasons and the rational suggestions are proposed in this paper. The sand stormy weather is the result of the special geographic environment and weather conditions. Changes in the number of days of strong wind are the reflections of the periodical change in climate. Why the strong sand stormy weather took place is that the anti El Nin~o case is at top, and the land cover deteriorates in the whole area but with part area improving. The dust weather mainly originated from mid west Inner Mongolia and northwest of Hebei Province. The dust is mainly consisted of soil dust from the origination area and the trace. The ground bare soil and sandy dust from construction site in urban extension areas also supplied materials for the local dust. In order to alleviate and control the dust damage, some suggestions were proposed as following: Firstly, the natural vegetation must be restored through planting tree or grasses in cultivated land instead of planting crops. Especially effective ecological protective shield must be established for Beijing and Tianjin city. The bare land of urban marginal areas must be treated in order to control local dust. Secondly, eco environmental construction must be paid more attention to during implementing Western Development Plan. Ecological benefits must be combined with economic and social benefits. Finally, the system for monitoring and predicting the sand stormy weather must be established and improved. Study on controlling and alleviating the dust disaster also need to be done.
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    Cited: Baidu(1135)
    Fu Bojie, Chen Liding, Ma Keming
    Acta Geographica Sinica    1999, 66 (3): 241-246.   doi: 10.11821/xb199903006
    Abstract794)      PDF (327KB)(1448)      
    Land use changes may influence a variety of natural phenomena and ecological processes, including soil conditions, water runoff, soil erosion and biodiversity. Irrational land use is one of the main reasons for the soil erosion and nutrient lose in the loess hilly area. The Yangjuangou catchment in the Loess Plateau of China, with typical loess hill and gully topography, was selected as the study area. The study focus on the affects of land use changes on soil erosion, the distribution of soil nutrient and soil moisture from catchment, and land use type at three spatial scales. Aerial photography interpretation and field survey mapping were used to produce land use maps in 1984 and 1996. GIS was used for data storage, analysis and display from a comparison of land use areal changes in 1984 and 1996. It was determined that the area of forest and grassland increased 42% and 5% respectively and slope farmland decreased 43%. Land use changes result in a decrease of soil erosion by 24%. Three types of typical land use structure during 15 years in the loess hill slope were selected in order to study the effect of land use structure on the distribution of soil nutrients and soil moisture. From the bottom to top of hills, the patterns of land use types are: grassland slope farmland forest, slope farmland grassland forest and slope farmland forest grassland. By measuring the contents of the total N, total P, available N, available P, organic matter of soil and soil moisture in 0 cm~70 cm depth, the results show that the land use structure type of slope farmland grassland forest has high contents of soil nutrients and low antecedent soil moisture. This indicates that this land use structure has a better capacity for retaining soil nutrient and a high efficiency for soil conservation. The analysis of soil nutrient and soil moisture in different land use types showed that the content of soil nutrient are: forest>grassland>slope farmland, while the content of soil water are: forest Related Articles | Metrics
    Cited: Baidu(1097)
    Analysis on Spatial Distribution Characteristics of Soil Organic Carbon Reservoir in China
    WANG Shao qiang, ZHOU Cheng hu, LI Ke rang, ZHU Song li, HUANG Fang hong
    Acta Geographica Sinica    2000, 67 (5): 533-544.   doi: 10.11821/xb200005003
    Abstract977)      PDF (324KB)(2181)      
    The paper respectively adopted physiochemical properties of every soil stratum from2 473 soil profiles of the second soil survey. The corresponding carbon content of soil is estimated by utilizing conversion coefficient 0 58. First, we calculated the carbon content of every stratum of different soil stirp in the same soil subtype. Then, we took soil stratum depth as weight coefficient to acquire the average physiochemical properties of various kinds of soil stirp. Finally, we got the average depth, organic content, duck density and carbon density of different soil subtypes through area averaging. The total carbon quantity of different kinds of soil can be calculated by the following expression: C j=0 58S jH jO W j where j is the soil type, C j is the carbon storage of j soil type, S j is the distribution area of j soil type, H j is the average depth of j soil type, O j is the average organic content of j soil type, and W j is the average bulk density of j soil type. In the second soil survey, the total amount of soil organic carbon is about 924 18?10 8 t and carbon density is about 10 53 kgC/m2 in China according to the statistic country area 877 63?106hm2. The spatial distribution characteristics of soil organic carbon in China are that the carbon storage increases with the increase of latitude in eastern China and the carbon storage decreases with the decrease of longitude in northern China. There is a transition zone where carbon storage varies greatly in China. Moreover, there is an increasing tendency of carbon density with the decrease of latitude in western China. Soil circle has implications on global change, but the difference in soil spatial distribution is substantial in China. Because the structure of soil is inhomogeneous, mistakes will be resulted in estimating soil carbon reservoir. It is thus necessary to farther resolve soil respiration, organic matter conversion and others related problems, and build uniform and normal methods of measurment and sampling.
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    Cited: Baidu(1083)
    County Level Economic Disparities of China in the 1990s
    LI Xiao jian, QIAO Jia jun
    Acta Geographica Sinica    2001, 68 (2): 136-145.   doi: 10.11821/xb200102002
    Abstract418)      PDF (355KB)(803)      
    This paper analyses regional economic disparities in China using nationwide county level data. Firstly, in contrast to the enlarging trend indicated by provincial level studies, economic disparities between counties were narrowed in the 1990s. This finding does not apply in the comparison between coastal and inland areas. The disparities between the two parts were continuously widened. Secondly, the counties with faster growth rates than the national average were spread from several growth centers to outside. Consequently, three growth corridors gradually appeared, namely, the Coastal Corridor (along the nation’s coastal line), Beijing-Guangzhou Corridor (along the railway from Beijing to Guangzhou), and the Changjiang River Corridor (along the Changjiang River from Chengdu to Shanghai). Thirdly, regional disparities exist within each corridor. There were numbers of relatively underdeveloped counties in the Coastal Corridor. Similarly, relatively developed counties were found in Western China. Fourthly, general speaking, the less developed counties were mainly located in the western part of China. The distribution pattern of less developed counties is consistent with the disadvantageous development conditions in mountainous, cold and dry areas, as well as with the isolation in the provincial border regions. Finally, this paper classifies counties into four categories by using their development status in 1990 and their growth rates from 1990 to 1998.
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    Cited: Baidu(887)
    Analysis on Spatial-Temporal Features of Land Use in China
    WANG Si-yuan, LIU Ji-yuan, ZHANG Zeng-xiang, ZHOU Quan-bin, ZHAO Xiao-li
    Acta Geographica Sinica    2001, 68 (6): 631-639.   doi: 10.11821/xb200106001
    Abstract830)      PDF (1134KB)(2190)      
    The research on land use and land cover change is a core for studies on the global changes. Also the research of spatial-temporal features of land use/land cover change is significantly important for better understanding land use/land cover change and environmental management for sustainable development. In order to study the spatial-temporal changes of land use and land cover, the technologies of remote sensing and geographical information system were used to analyze the spatial dynamical features and temporal dynamical features of land use in China. The mathematical methodology for study on land use change was explored and developed. This research focuses on the dynamical analysis of spatial-temporal features of land use and land cover change of China in recent five years, such as land use types, land use degree, plantation status, city expansion, and so on. The results are: the cultivated land, water area, built-up or non-arable land area are increasing and forestland and grassland keep decreasing in the five years. The change of land cover types is not obvious in the corresponding period. The area-change of cultivated land has taken place mostly in the middle and eastern China. However, the area-change of forestland and grassland and unused land has mainly taken place in the Xinjiang Uygur Autonomous Region, the Inner-Mongolia Autonomous Region and Heilongjiang Province in China.
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    Cited: Baidu(722)
    Analysis on Spatial-Temporal Features of Land Use in China
    WANG Si-yuan, LIU Ji-yuan, ZHANG Zeng-xiang, ZHOU Quan-bin, ZHAO Xiao-li
    Acta Geographica Sinica    0, 0 (): 631-639.  
    Abstract0)      PDF (1134KB)(3)      

    The research on land use and land cover change is a core for studies on the global changes. Also the research of spatial-temporal features of land use/land cover change is significantly important for better understanding land use/land cover change and environmental management for sustainable development. In order to study the spatial-temporal changes of land use and land cover, the technologies of remote sensing and geographical information system were used to analyze the spatial dynamical features and temporal dynamical features of land use in China. The mathematical methodology for study on land use change was explored and developed. This research focuses on the dynamical analysis of spatial-temporal features of land use and land cover change of China in recent five years, such as land use types, land use degree, plantation status, city expansion, and so on. The results are: the cultivated land, water area, built-up or non-arable land area are increasing and forestland and grassland keep decreasing in the five years. The change of land cover types is not obvious in the corresponding period. The area-change of cultivated land has taken place mostly in the middle and eastern China. However, the area-change of forestland and grassland and unused land has mainly taken place in the Xinjiang Uygur Autonomous Region, the Inner-Mongolia Autonomous Region and Heilongjiang Province in China.

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    Cited: Baidu(722)
    An Analysis of Spatial Structure and Optimal Regional Development
    LU Da dao
    Acta Geographica Sinica    2001, 68 (2): 127-135.   doi: 10.11821/xb200102001
    Abstract649)      PDF (115KB)(921)      
    This paper is a further analysis of the “Pole Axis Theory” and related “T shaped” spatial structure of the industrial allocation in China, which was developed by the author a decade ago. It starts with an analysis of the relationship between different types of spatial structure and regional development, and of how to achieve optimal regional development through optimal spatial organization as well. Then, based upon existing theories and practices in China, it discusses the formation of the “pole & axis” system by disclosing the evolution of socio economic organization and demonstrates that such a system is the most efficient spatial structure that can lead to optimal regional/national development. Lastly, the paper concludes that the strategy of a “T shaped” spatial structure of industrial allocation, which is an application of the “Pole Axis Theory”, has played a very important role in the spatial economic development in China in the last decade.
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    Cited: Baidu(713)
    The Calculation and Analysis of Ecological Footprints of Gansu Province
    XU Zhong min, ZHANG Zhi qiang, CHENG Guo dong
    Acta Geographica Sinica    2000, 67 (5): 607-616.   doi: 10.11821/xb200005010
    Abstract768)      PDF (238KB)(899)      
    Because humans consume the products and services of nature, every one of us has an impact on the earth. Does the human load stay within global carrying capacity? The ecological footprint concept has been designed to answer this question and estimate man’s impact on nature. The ecological footprint of any defined population (from a single individual to a whole city or country) is the total area of ecologically productive land and water occupied exclusively to produce all the resources consumed and to assimilate all the wastes generated by population. The ecological footprint method presents a simple framework for national natural capital accounting. The concept of ecological footprint and its calculation method is introduced in this paper. The paper also analyses the advantages and disadvantages of the ecological footprint model, and addresses the types of ecologically productive lands. The article calculates and analyses the ecological footprint of Gansu province in 1998. The ecological footprint ledger is composed of three main section. The first ledger is basic biotic resources consumption including its byproducts, the second is energy consumption, the third is trade balance. Trade balance through more detailed trade flow analyses can mitigate the influence of import and export product on consumption variations. Based on the ecological footprint concept and analysis framework, human consumption can be compared with regional level natural capital production using existing data. In the case of Gansu province, the ecological deficit of Gansu is 0 564 2 hm2 per capita. Simplification of calculation methodology to certain extent results in over optimistic estimates. Finally, the ecological footprint model’s advantages and disadvantages are identified. Ecological footprint index is an excellent aggregate index that connects many issues of sustainability, development and equity. The model can reveal the extent to which local carrying capacity has been exceeded and allows a cumulative approach to impact analysis. The use of ecological productive area as a numeraire, rather than money or energy, makes the footprints easy to be understood, and also permits provocative calculations. The limitations of the model is that it doesn’t include several important issues, which are even directly related to land use: land areas lost to biological productivity loss of land because of contamination, erosion and urban “hardening” and dissertation (especially in north western China). Methodologically, the assessments could be more complete by including the ecological spaces used for freshwater use, a particular important issue in arid area of north western China.
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    Cited: Baidu(690)
    The Spatio-temporal Variability of Soil Nutrients in Zunhua Plain of Hebei Province: Semivariogram and Kriging Analysis
    GUO Xu dong, FU Bo jie, CHEN Li ding, MA Ke ming, LI Jun ran
    Acta Geographica Sinica    2000, 67 (5): 555-566.   doi: 10.11821/xb200005005
    Abstract573)      PDF (609KB)(991)      
    Geostatistics has proven to be useful for characterizing and mapping spatial variability of soil properties, however, most of the previous geostatistical studies were focused on data at small scale. With the development of GIS and GPS, geostatistcs and GIS are becoming indispensable in characterizing and summarizing spatial information in large regions to provide quantitative support to decision and policy making for soil, agricultural and natural resources management. In this paper, we applied geostatistics combined with GIS to analyze the spatio temporal variabilities of the available potassium, available phosphorus and organic matter in soil surface (0~20 cm) in Zunhua county (municipality) of Hebei province over 20 years from 1980 to 1999. Results showed the average content of the available potassium, available phosphorus and organic matter in soil surface in 1980 was 77 78 mg/kg, 19 46 mg/kg, 1 14%, respectively; and that in 1999 was 90 12 mg/kg, 25 7 mg/kg, 1 54%, respectively. Paired samples t test of soil nutrients and the results estimated by block kriging indicated the content of the available potassium, available phosphorus and organic matter in 1999 was significantly higher than that in 1980. The ratio of nugget to sill of the three soil nutrients varied from 32 3% to 60%, indicating the spatial correlation of the three tested soil nutrients at this large scale was moderately dependent. The ratio of nugget to sill of available potassium was 56 5% in 1980 and 41 1% in 1999, that of the available phosphorus was 45 5% in 1980 and increased to 54 1% in 1999. The ratio of organic matter changed considerably from 60% in 1980 to 32 3% in 1999. The range of the available potassium and available phosphorus between the year of 1980 and 1999 was almost the same, however, the range of organic matter was from 4 8 km in 1980 to 2 7 km in 1999. The improvement of the available potassium and available phosphorus in soil was mainly contributed to the more application of fertilizers, and the content of organic matter was affected by the changes of tillage and land use, which also altered the spatial distribution of soil nutrients to different degrees over the past 20 years.
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    Cited: Baidu(680)
    The Minimum Area Per Capita of Cultivated Land and Its Implication for the Optimization of Land Resource Allocation
    CAI Yun-long, FU Ze-qiang, DAI Er-fu
    Acta Geographica Sinica    2002, 57 (2): 127-134.   doi: 10.11821/xb200202001
    Abstract915)      PDF (631KB)(771)      

    Cultivated land, different from other resources, is fundamental to the sustainable development of Chinese agriculture, society and economy. Market mechanism inevitably drives cultivated land into industrial and urban uses. Rapid industrialization and urbanization lead the scarce cultivated land resources to more crises. So market is a failure to allocate this kind of resource which can be regarded as common property in a certain sense. Government intervention is necessary for optimization allocation of cultivated land. Current policy of macro-administration for cultivated land conservation is oriented to total quantitative control. Every province is demanded that the total number of cultivated land remains not decreased. This policy is difficult for practicing because it does not consider various situations in different regions. For example, in eastern provinces where rapid industrialization and urbanization is proceeding and reserved arable land is scarce, the total number of cultivated land will inevitably decrease unless at the cost of lowering the economic growth. Therefore, it is necessary to innovate the policy of cultivated land resources conservation and utilization. The authors put forward the concept of minimum area per capita of cultivated land (MAPCCL) as a new insight into the optimization of land resource allocation for policy making. MAPCCL can be defined as the minimum number of cultivated land that can meet the needs of food consumption under certain food self-sufficient rate and land productivity. PICL provides a threshold of cultivated land conservation. If K<1, some cultivated land may be conversed into urban and industrial uses and planting structure may be adjusted for more cash crops. If K>1, cultivated land should not be conversed into other uses or land quality and productivity should be enhanced by means of increasing input and technological innovation.

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    Cited: Baidu(625)
    Change in Extreme Temperature and Precipitation over Northern China During the Second Half of the 20th Century
    ZHAI Panmao, PAN Xiaohua
    Acta Geographica Sinica    2003, 58 (7s): 1-10.   doi: 10.11821/xb20037s001
    Abstract1239)      PDF (1033KB)(1401)      

    Study on change of weather and climate extremes has become an important aspect in modern climate change research. Based on the daily surface air temperature data from 200 stations and daily precipitation data from 739 stations during the second half of the 20th century, schemes for analyzing climate extremes were designed mainly according to percentiles of a non-parametric distribution and the gross errors in the daily data were removed based on a newly designed quality control procedure. The spatial and temporal characteristics of change of climate extremes over northern China were studied. The main conclusions are summarized as follows: 1) The number of days with maximum temperatures over 35oC decreased slightly. The decreasing trends are obvious in the North China Plain and the Hexi Corridor. However, since the 1990s, the extreme hot days increased greatly. Meanwhile, the frost days decreased significantly in northern China, especially in the eastern part of northern China and Xinjiang Uygur Autonomous Region. Increase trends were found for the 95th percentiles of daily maximum temperatures except in the southern part of North China, while obvious decrease trends were found for the 5th percentiles of daily minimum temperatures. 2) The extreme intense precipitation events obviously increased in much of northwestern China but decreased in the eastern part of northeastern China and most parts of North China. The number of heavy rain days increased in eastern Inner Mongolia and eastern Northeast China, but obviously decreased in the Northeast China Plain and North China.

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    Cited: Baidu(588)
    Study on the Tourist Resources Classification System and Types Evaluation in China
    GUO Lai xi, WU Bi hu, LIU Feng, FAN Ye zheng
    Acta Geographica Sinica    2000, 67 (3): 294-301.   doi: 10.11821/xb200003005
    Abstract1150)      PDF (235KB)(1962)      
    Tourist resources are the material basis of sustainable tourism and the potentiality of tourism economic growth. As the working criterion and technical guide for investigating tourist resources, the classification system of tourist resources is a very important premise of the work. Based on the criterion for investigating Chinese tourist resources, the new classification system was put forward. The newly added are three serials of natural, human and service; ten types of geologic landscape, water scene, climate and biology, other natural scene, historic heritage, modern human attractions, abstract human attractions, other human attraction, service resource and other service resources; plus ninety eight patterns. There are three grades to indicate the scale of monocase of tourist resources, which are field, segment and site. The tourist resources also can be divided into three states: developed, to be developed and latent. Based on this new classification system, more consummate characteristic item was revised, and the quantitative evaluation of types tourist resources was carried out by taking the Beihai City as an example to validate this system and methods. In the end, the paper points out that in order to achieve sustainable tourism, China must consummate the criterion for investigating tourist resources, and expand investigations to provide a series of tourist extractive engineering for building China into a country even more attractive to tourists in the world.
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    Cited: Baidu(569)
    The Ecological Footprints of the 12 Provinces of West China in 1999
    ZHANG Zhi qiang, XU Zhong min, CHENG Guo dong, CHEN Dong jing
    Acta Geographica Sinica    2001, 68 (5): 599-610.   doi: 10.11821/xb200105011
    Abstract700)      PDF (425KB)(729)      
    The quantitative measurement of sustainable development has become one of the frontiers of sustainable development research since the sustainable development concept was put forward The ecological footprint indicator, put forward and developed by W E Rees and M Wackernagel since the early 1990s, is to measure the human impact on the earth and judge whether the human load stays within global carrying capacity The ecological footprint of any defined population (from a single individual to that of a whole city or country) is the total area of ecologically productive land and sea occupied to produce all the resources and services consumed and to assimilate all the wastes generated by that population With an area of about 6 88?10 6 km 2 which accounts for 71 67% of the total land area of China and 3 57?10 8 people accounting for 28 3% of the total population of China, the 12 provinces of West China have relatively low population density, and are abundant in natural resources but backward in economic development It is important to study the usage status of natural resources and sustainability of the 12 provinces of West China Based on the introduction to the concept and calculation method of ecological footprint indicator, the authors calculate and analyze the ecological footprints of the 12 provinces of West China in 1999 according to the data of the statistical yearbooks of these provinces According to this calculation, Yunnan Province and the Tibet Autonomous Region were the two provinces with ecological surplus, the other 10 provinces were all with ecological deficit The ecological surplus of Yunnan and Tibet were 0 145 hm 2 and 5 431 hm 2 per capita, respectively The Xinjiang Uygur Autonomous Region and Guizhou Province were the two provinces that have the largest ecological deficit, 1 261 hm 2 and 0 876 hm 2 per capita, respectively The ecological footprint and ecological deficit per capita of the 12 provinces of West China in 1999 were 1 172 hm 2 and 0 469 hm 2, respectively The total ecological footprint deficit of the 12 provinces of West China in 1999 is 1 625?10 6 km 2,which is equivalent to the area of the Xinjiang Uygur Autonomous Region The ecological footprint deficit shows that the human load has already stayed beyond the regional bio capacity, and the regional natural ecosystem is under great pressure of human activities We also point out the sustainability of the 12 provinces of West China according to the results of ecological footprints, and analyze the use efficiency of natural resources by calculating the ecological footprint needs of gross domestic product (GDP).
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    Cited: Baidu(550)
    Shi Yafeng, Li Jijun, Li Bingyuan, Yao Tandong, Wang Suming, Li Shijie, Cui Zhijiu, Wang Fubao, Pan Baotian, Fang Xiaomin, Zhang Qingsong
    Acta Geographica Sinica    1999, 66 (1): 10-20.   doi: 10.11821/xb199901002
    Abstract1093)      PDF (333KB)(1603)      
    Pressed by the northward movement of the Indian Plate, The crust in the Qinghai Xizang (Tibetan) area was uplifted during the Late Cenozoic, which exerts a great influence on East Asian environment. The Qinghai Xizang area was subject to two cycles of uplift and plantation in the Tertiary. The Plateau had raised up to about 2 000 m above sea level during 25 Ma BP~17 Ma BP. This, coupled with favorable continent ocean configuration at that time, may have triggered Asia monsoon, which replaced previously dominated planetary wind system and led to a big environmental shift in China in the Middle-Tertiary because of global cooling and plantation in Xizang. Monsoon decreasing resulted in intensification of the Asian dry climate after 8 Ma BP. The rapid uplift of the Qinghai Xizang Plateau in the Last 3 4 Ma had enhanced in a great deal again the summer monsoon, leading to moistening of the northern Plateau and even North China. On the other hand, the intensification of winter monsoon resulted in deposition of Loess at 2 5 Ma BP in North China. The subsequent tectonic movement of Mid-Pleistocene (0 8 Ma BP~0 5 Ma BP) might raise the Plateau up to about 3 000 m~3 500 m above sea level. This coupled with temperature drop by periodicity shift in the earth orbit, and led the Plateau to enter the iceosphere and form the maximum glaciating with ice cover of over 500 000 km2. Because of strengthen of winter monsoon, desert in the northwest China was enlarged and Loess sediment expanded far to the lower reaches of the Yangtze River. Intense tectonic uplift happening in the last 150 ka, led to significant change of many local drainage system in the plateau. Based on 150 ka high resolution climatic records from the Guliya ice core, lake cores at Tianshuihai and Zoige, and loess profile at Linxia, it is found that the climate in MIS 5e was especially warm. The ice core record indicated temperature at 125 ka BP was 5℃ higher than that of today and climate was unstable in MIS 5e in the plateau, which was revealed also by loess and lake core records. The deglaciation since 15 ka BP was characterized by a clear identification of the Younger Dry as event at ac.. 12 ka BP followed by largely fluctuation rising of temperature with its warmest peak at 7 ka BP, corresponded with increase of precipitation, expansion of lakes. After 5 ka BP, temperature decreased again in fluctuation, accompanied with environmental deterioration. Repeated leveling indicates that the Plateau is still in rapid rising at an average rate of 5 8 mm/a in present time.
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    Cited: Baidu(544)
    Regional Carrying Capacity in Bohai Rim
    MAO Han ying, YU Dan lin
    Acta Geographica Sinica    2001, 68 (3): 363-371.   doi: 10.11821/xb200103013
    Abstract531)      PDF (232KB)(679)      
    Bohai Rim, one of the developed and urbanized regions in China, plays an important role in the new century development. Now the load on the regional resource and environment has been over carried which has been one of the main restrictive factors for the future socioeconomic development in this region. After retrospection of the previous research methods on regional carrying capacity at home and abroad, this paper takes the state space as a basic method to measure regional carrying capacity on account of implementing regional sustainable development strategy. It does quantitative evaluation of regional carrying capacity by building an index system. The conclusions are as follows. The carrying status of resource and environment was over loaded from 1994 to 1998 in this region. Seriously inadequate per capita possession of water resource and utilizable water decreasing caused by pollution are main restrictive factors. Furthermore serious shortage of water resource has close relationship with furious speed extensive economic development pattern. In view of the above mentioned conclusions, this paper simulates and forecasts the regional carrying capacity and status by the agency of system dynamics. The general trend is briefed below. The over loaded tendency remains as before, but the carrying status of each time is evolving toward better. It is forecasted that the carrying status will approach the carrying capacity in the year 2015 which shows this region will develop from weaker to stronger sustainable direction. According to this forecast, the authors raise four countermeasures as follows: (1) economic countermeasure: seeking continuous, moderate and coordinated economic growth and adjusting the industrial structure and location; (2) resource countermeasure: adopting the principle of increasing income and decreasing expenditure for shortage resources and building the regulation of utilizing resource upon consideration; (3) environmental countermeasure: strictly executing the total emission control of pollutant, adopting the resource consumption into national economic accounting system progressively and increasing the input to improve eco environmental quality; and (4) population countermeasure: strictly controlling the quantity and improving the quality.
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    Cited: Baidu(499)
    Spatial Structure of Tourist Source Areas for the Naturally Scenic Sightseeing Places:A Case Study of Jiuzhaigou
    ZHANG Jie, DU Jin kang, ZHOU Yin kang, ZHANG Si yan, PAN Bing
    Acta Geographica Sinica    1999, 66 (4): 357-364.   doi: 10.11821/xb199904008
    Abstract805)      PDF (383KB)(1067)      
    The spatial structure of the source or market areas of tourists is basic to tourist geography. Although there are case studies on such issues as mathematical modeling of distance decay of tourists from a tourist site, its market potential and actual market structure, many questions remain. Take tourist distance decay for example. Whereas hypothetical theoretical curves have been suggested, no basic mathematical model based on case studies exists. In addition, the application of distance cumulative curve in tourist research is still limited to descriptions of the actual distribution of tourists, which is ineffective in analyzing the spatial structure of tourist market potential. Jiuzhaigou Conservation District, one of China’s most picturesque tourist areas with numerous colorful lakes and waterfalls, is recognized by UNESCO as one of the world’s natural heritage sites. Distance decay model is used to reveal the characteristics of its market area structure. Several types of distance cumulative curve are also used to reveal its market structure at varying distances from the site. A sample of more than 16 000 tourists was obtained from entrance registration which shows the they come from 235 cities and counties. Through regression analysis we calculated the main coefficients of the distance decay model and found that the best fit model is the Pareto model with a distance decay exponent of 0 48. The next best are the lognormal model and square root exponential model, while the normal model is unfit. As the relative coefficients of these models are not high enough, we used the gravity model to analyze distance decay versus the influence of population and economic growth. The result shows a distance decay exponent of 1.84 and a clear increase in relative coefficient to 0 70. Gravity model was also used to better understand how the sampled tourists declined proportionally with increasing distance from the site. The result shows the distance decay exponents range between 1 74 and 1 92. When per capita industrial and agricultural output is replaced with total industrial and agricultural output of cities and counties, the exponents range between 2 5 and 3 0. This study demonstrates that the several distance cumulative curves of the market areas of the site and the population of the market areas can be effectively used to analyze the spatial structure of the site’s ultimate market area potentials.
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    Cited: Baidu(478)
    Discussion on the Index Method of Regional Land Use Change
    ZHU Huiyi, LI Xiubin
    Acta Geographica Sinica    2003, 58 (5): 643-650.   doi: 10.11821/xb200305001
    Abstract914)      PDF (983KB)(1122)      

    Recently, many sorts of index models have been widely adopted in the analysis of land use change in China. And they do play an important role in summarizing the rule of regional land use changes. However, according to the present research papers, there are some confusions and misuses in their applications, which root in faultiness, abnormity and misunderstanding of the indices or index calculation. By detailed exploration of the indices embedded in research materials, three classifications are identified on the basis of their application purposes: the change of regional land resources (change rate index and level change index), the direction of land use change (transition matrix and flow direction rate) and the spatial pattern of land use change (dynamic degree, relative change rate, adjacency degree, barycenter, frequency degree and importance degree). Then all the indices listed above are discussed under the purposed framework, including their concepts, calculation methods, application fields, misuses, and some application suggestions. This paper also gives a remark in the end that the research of land use change needs new breakthroughs in both theory and methodology. Index method is only a simple kind with limited functions, and much more efforts should be devoted to integrative, predictive methods in the coming days.

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    Cited: Baidu(463)
    The Evolvement of Spatial Structure and the Significance of Guilin's Domestic Tourist Origins
    BAO Ji-gang, ZHENG Hai-yan, DAI Guang-quan
    Acta Geographica Sinica    2002, 57 (1): 96-106.   doi: 10.11821/xb200201011
    Abstract533)      PDF (748KB)(668)      

    This paper uses the first-hand data of 1987 and 1999 to analyze the spatial evolvement of Guilin's domestic tourist origins of the years concerned. It is revealed that the number of tourists increased steadily after 1980, while the 1980s were the golden era of Guilin's domestic tourism development. The spatial concentration index (SCI) of tourist origins indicates a drop of 12% from 1987's 43.50 to 1999's 38.27, which means that after 12 years, Guilin's tourist origins have expanded and have become more stable, while the spatial distribution has become less concentrated. Taking into account the increment percentage of tourists from each tourist origin, the paper develops a formula to calculate the attraction radius (AR) of tourist destination (TD) revised from the formula of standard distance given by Stephen Smith (1989). Using the railway distance between Guilin and the capital city of each province as the mean of the traveling distance from each region, the paper shows that Guilin's AR raised by 40.84% from 1987's 568.12 km to 1999's 800.14 km. From the view of macroeconomics, we consider the following as the possible reasons for the drop of Guilin's SCI and the rise of its AR: firstly, as a long-established tourist destination, Guilin's word-of-mouth reputation played a very important role in attracting tourists. Secondly, the rapid increase of living standard and the practice of long weekends/vacations has brought China to a golden era of domestic tourism where more people travel more frequently than before. Thirdly, the social and economic development in areas such as Beijing, Shanghai, Jiangsu, Shandong, has made it possible for Guilin to attract more tourists from them. As a result, the spatial distribution of Guilin's domestic tourists origins has developed a pattern that is different from the law of distance decay. Fourthly, the degree of increment in a tourist origin is mainly due to two factors--spatial distance and the level of economic development. A place near a tourist destination may have a low increment of market share because of its low level of economic development. A place far from a tourist destination may have a high increment of market share because of its high level of economic development. The intervening opportunity is probably the fundamental factor to analyze this phenomenon. According to the conclusion, the paper proposes some guidelines for Guilin's tourism marketing. Finally, the paper discusses briefly the difference of evolvement in the domestic tourist markets between Guilin and Huangshan.

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    Cited: Baidu(456)
    Spatio-temporal Change of Land Use in Bohai Rim
    ZHU Hui yi, LI Xiu bin, HE Shu jin, ZHANG Ming
    Acta Geographica Sinica    2001, 68 (3): 253-260.   doi: 10.11821/xb200103001
    Abstract709)      PDF (466KB)(1523)      
    Regional land use change is an important part of global change The Bohai Rim is one of the hot spots for socio economic development in China, so the land use change will be improved greatly Based on the RS and GIS methods, we analyze the land use information from 1985 and 1995 TM images, then in both spatial and temporal aspects, we analyze the situation of land use change in the region It is found: (1) The land use changed greatly in the Bohai Rim during 1985~1995 The cultivated land decreased by 1 800 000 hm 2, forestland increased by 600 389 hm 2 and land for housing and other construction purposes increased remarkably in the last ten years (2) The speed of the land use change in the region was up to 0 85% per year The cultivated land decreased at the rate of 1 26% per year, land for housing and other construction purposes, water area, and forestland increased at different rates, among which land for housing and other construction purposes and water area were the highest (up to 6 40% and 6 95% per year respectively) (3) There were notable differences of land use change among the sub areas in the region For cultivated land change, Beijing and Liaoning Province (partly) was the greatest, Hebei Province the smallest For land for housing and other construction purposes, Liaoning (partly) was the greatest, Beijing the second, Tianjin the smallest in land use change (4) As to the spatial change, 30% of the area in the region was under the changing process, major types of which were cultivated land turned to be land for housing and other construction purposes, and cultivated land turned to be forestland and grassland Those types of land were distributed widely and differently in different areas, but mostly near the mountains and in areas joining the town and country (5) The direction of land use change in the region was to occupy cultivated land for and convert land between forest and cultivated land at different units into that for housing and other contruction purposes.
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    Cited: Baidu(451)
    Distribution and Seasonal Change of Net Primary Productivity in China from April, 1992 to March, 1993
    SUN Rui, Zhu Qi jiang
    Acta Geographica Sinica    2000, 67 (1): 36-45.   doi: 10.11821/xb200001004
    Abstract621)      PDF (499KB)(886)      
    It is significant to estimate terrestrial net primary productivity (NPP) accurately not only for global change research, but also for natural resources management to achieve sustainable development. The estimation of NPP by climate data is only a potential NPP rather than true NPP. But remote sensing data can describe large scale distribution of plant resources better. So, 1 km AVHRR NDVI data was used adopted here to estimate the distribution of NPP in China. First, the fraction of absorbed photosynthetically active radiation (FPAR) by vegetation is derived from NDVI data using the linear relationship between FPAR and vegetation index. The incident PAR was estimated by climate data. Then NPP was calculated with absorbed PAR and energy efficiency ε * g . In order to estimate NPP more accurate, the effects of temperaturely, soil water content and plant respiration were also considered in the model. The model can be described as below:NPP=ε g×f 1(T)×f 2(β)×FPAR×PAR-Rin which f 1(T) and f 2(β) mean the temperature and soil water content effects on photosynthesis, R means plant respiration including maintenance respiration and growth respiration. Monthly and annual net primary productivity in China was computed by monthly 1km AVHRR NDVI data, climate data between April, 1992 and March, 1993, vegetation type map and soil texture map. The results gained were compared with ground-observation and Miami model results. It shows that the results using remote sensing data are closer to truth. Total annual NPP in China is 2 645×10 9tC. The distribution of NPP in China is mainly effected by precipitation and has the trend of decreasing from south east to north west. Finally, the seasonal change of NPP was investigated on the basis of monthly NPP.
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    Cited: Baidu(441)
    Touristic Ecological Footprint Model and Analysis of Huangshan City in 2002
    ZHANG Jinhe, ZHANG Jie
    Acta Geographica Sinica    2004, 59 (5): 763-771.   doi: 10.11821/xb200405015
    Abstract577)      PDF (1166KB)(503)      

    Based on the theory and method of ecological footprint, combined with the ecological consumption and its structural character of tourist, the paper, taking the Huangshan City as an example, calculates and analyses the touristic ecological footprint and its efficiency of Huangshan City in 2002. Six characteristics have been summarized: (1) The touristic ecological footprint of Huangshan City is 0.106 hm2 per capita in 2002. In comparison, the fossil energy land is about 88.23% of this footprint, tourist transportation and food are the main constitutes of the total footprint, about 55.67% and 33.90%. (2) The ecological deficit of Huangshan City is 0.219 hm2 per capita in 2002. About 48.40% of the ecological deficit is a result of touristic ecological footprint. (3) Extrapolating the footprint of a tourist to Huangshan City (3.13 days) to 1 year, results in an area of 12.36 hm2 per capita in 2002, almost 9 times that of the average footprints of citizens of Huangshan City. (4) In Huangshan City, the average tourist output of 1 hm2 ecological footprint is US$684, 1.17 times the average output of the Huangshan City' citizens ecological footprint, 61.84% that of the world. (5) Dimensions of tourist flows, tourist consumption level and model, tourist spatial behavior, the policy and stratagem of the tourist destination are the key factors to affect the size of touristic ecological footprint. (6) The shift of TEF among regions will result in shift and diffusibility of tourist ecological responsibility, ecological influence and ecological stress among regions in the world, and tourism development may have profound impacts on global environments.

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    Cited: Baidu(441)
    Xu Xueqiang, Hu Huaying, Ye Jiaan
    Acta Geographica Sinica    1989, 56 (4): 385-399.   doi: 10.11821/xb198904001
    Abstract637)      PDF (699KB)(1050)      
    The approach to studying the social spatial structure of cities has become very popularin the western countries since the first study of social area analysis was undertaken by Shevkyet al. in 1950s. During 1960s, this approach area was developed by using the technique of fac-torial ecological study. This technique has two characteristics. First, a large number of va-riables are used in the factor analysis or the principal components analysis, in order to extractsome major factors of social and residential differentiation. Second, it places much greateremphasis on the spatial patterns associated with those factors.
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    Cited: Baidu(436)
    Cui Gonghao, Wu Jin
    Acta Geographica Sinica    1990, 57 (4): 399-411.   doi: 10.11821/xb199004002
    Abstract512)      PDF (3283KB)(1466)      
    The development of Chinese urban fringe is making way into a new stage. It has the characteristic that urban expansion and rural-urbanization promote or carry on simultaneously. This development way of urban fringe is different from that of developed and the other de-veloping countries. The development and changes of Chinese urban fringe is related to de-veloping stage of industrialization and urb;mization. It could divided into three stage: 1) Agri-cultural type's fringe stage (1949-1959), 2) semi-industry type's fringe stage (1960-1978), 3) industry type's fringe (1979-1989). At present, the main problems of Chinese urban fringe are shown as follow: 1) The con-struction of urban fringe is very disordered because of the lack of effective planning policies and theoretical guidance, so there are a lot of problems in achieving an appropriate balance between urban development and resources and environmental protection 2) Since urban frings is situated in city-country combinative area that is no longer rural but is not yet urban, its plann-ing is not only different from that of rural, various built-up area, but also different from that of rural, various index of planning is urucertain. 3) Urban fringe is also a dynamic zone that is undergoing because of it contact with the city, the contradictory of city's expansion and farmland is very prominent, city's expansion caused the heavy loss of prime farmland of fringe. 4) The social and industrial structure of fringe is not stable, economic system is very complex and economic activities and resources tend to focus on the short-term benefits.
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    Cited: Baidu(431)
    Comprehensive Evaluation and the Driving Factors of China's Urbanization
    CHEN Mingxing, LU Dadao, ZHANG Hua
    Acta Geographica Sinica    2009, 64 (4): 387-398.   doi: 10.11821/xb200904001
    Abstract1535)      PDF (1871KB)(1635)      

    From the essential meaning of urbanization, this paper establishes a comprehensive evaluation index system, including four aspects changing: population, economy, society and land. Based on the method of entropy, the measure and evolution of China's urbanization are analyzed since 1981. The results show that China's comprehensive urbanization level continues improving. Economic growth and geographical landscape are the main features of rapid evolution of urbanization, followed by the population urbanization, and the medical care level of social urbanization is the least advanced. The evolution of all the four subsystems has unique characteristics. The analysis of multiple regression model shows that the driving factors have been diversified. The market force is the most powerful driving force of China's urbanization, followed by intrinsic force, administration force, exterior force. From different stages of urbanization, the effects of market force, exterior force and the administration force on urbanization are increasing, while intrinsic force is decreasing. China's urbanization is the main endogenous process, hence more policies should be formulated to strengthen the market economy reform and coordinate urban and rural development.

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    Cited: Baidu(425)
    A GIS-based Approach to Flood Risk Zonation
    ZHOU Cheng hu, WAN Qing, HUANG Shi feng, CHEN De qing
    Acta Geographica Sinica    2000, 67 (1): 15-24.   doi: 10.11821/xb200001002
    Abstract499)      PDF (545KB)(1990)      
    Flood risk can, in general terms, be defined as probability time consequence. It consists of flood hazard analysis, vulnerability analysis and damage evaluation. A variety of methods have been developed and applied. Among them, Quantitative Risk Analysis (QRA) is a method of quantifying risk through systematic examination of the factors contributing to the flood hazard and affecting the severity of flood consequence, their interaction and relative contribution to the occurrence of the flood. The QRA technique is well established in many fields such as chemical engineering and hazardous materials processing. The application of QRA to flood risk is relatively new and still under development. While the basic risk assessment concepts and tools can be used, the methodologies need to be adapted. Category-based model for flood risk analysis is used to assign a value to each driven-factor such as triggering factor of rainfall, dam break, ground surface conditions of topography, land cover, and others. The keys to the model are to synthesis the spatial-referenced data and create the risk zone. The diffusion of Geographical Information Systems (GIS) technology opens up a range of new possibilities for hazard mitigation and disaster management. Microzonation is greatly facilitated by the kind of automation that GIS offers, especially as it involves comparison, indices and overlays in much the same way that GIS does. In this article, ArcInfo GIS has been chosen to quantitatively represent the influencing factors, spatialize the data into the uniform grid system, and transfer all the data item into the effect degrees on the probability of flooding. At last, with the support of Arc/Info GRID model, a categorical model for flood risk zonation has been put forward. The approach has been applied to the Liaohe river basin, the north-eastern of China, flood disaster risk zonation. The results show that the flood risk of the lower reaches of the Liaohe river is more serious than other places, which accord with the fact. The case study showes that the GIS-based category model is effective in flood risk zonation.
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    Cited: Baidu(418)
    Land Use Pattern in Transect of the Yangtse River and Its Influential Factors
    LONG Hua lou, LI Xiu bin
    Acta Geographica Sinica    2001, 68 (4): 417-425.   doi: 10.11821/xb200104005
    Abstract501)      PDF (345KB)(579)      
    The terrestrial transects of IGBP emphasize on explaining issues concerning global change through gradient methods, and land use is one of the gradient factors. The socio economic development extent, largely influencing decade scale land use change, is mainly taken into account to determine the research sphere of transect of the Yangtse River. Accordingly, considering the boundary of district, it covers an area of 1.12 million km 2 or so, contains 310 counties/cities, under jurisdiction of 11 provinces (autonomous regions, municipalities) of Shanghai, Jiangsu, Anhui, Jiangxi, Hubei, Hunan, Chongqing, Sichuan, Yunnan, Qinghai and Tibet. Supported by geographic information system, the land use pattern after a decade or more rapid socio economic development in transect of the Yangtse River is obtained through analyzing and dealing with the land use data of the mid 1990s. Then, canonical correlation analysis is applied to identify the influential factors of land use pattern in transect of the Yangtse River. Through operations of the statistical package for social sciences (SPSS) and specific analysis of the results, the contribution of each influential factor to land use pattern can be identified quantitatively. At the same time, tests are carried out through the canonical correlation coefficient and redundancy analysis. It is concluded that the land use pattern in transect of the Yangtse River is affected by physical factors and socio economic factors synthetically. Through foregoing analysis, abstracted influential factors involve height above sea level, temperature, terrain, economic density (i.e. GDP value per km 2), and village labors density. The distribution of pasture shows positive correlation with height above sea level and negative correlation with the warmest month average temperature, and it implies that pasture is usually distributed in the region with high sea level and low temperature. The positive correlation between economic density and the distribution of land for urban and rural construction shows that rapid socio economic development has been resulting in continuing sprawl of land for urban and rural development. The two factors of the coldest month average temperature and slope have positive correlation with the distribution of woodland. Furthermore, positive correlation between village labors density and the distribution of farmland implies the more village labors in a region, the more farmland proportion.
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    Cited: Baidu(409)