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    Earth Surface Processes
  • Earth Surface Processes
    DONG Yu-xiang, MA Jun, HUANG De-quan
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    A total of 47 samples were collected on typical coastal transverse ridge at Changli Golden Coast in Hebei Province, which is one of the most typical coastal aeolian distribution regions in China and is famous for the tall and typical coastal transverse ridges. The parameters of grain size of the 47 samples were analysed and calculated by use of the number of mean size, standard deviation, skewness and kurtosis. The results showed that, as for the deposits on the surface of transverse ridges in Changli Golden Coast, under the same depositional environment the particle size at windward slope base, windward slope, dune crest, leeward slope and leeward slope base as a whole belonged to the medium sand with better sorting, approximately symmetric skewness and moderate kurtosis.Some differences existed in the particle-size parameter value at different sites, especially the mean particle size at different sites of the transverse ridges surface greatly, i.e. , the particle size became finer and the sorting became much better from windward slope base and leeward slope base to the crest of transverse ridges, particle size at leeward slope was relatively finer than at the windward slope, the sorting at leeward slope also better than at the windward slope. As for the whole dune surface, the particle size was the coarsest at leeward slope base and the finest at the crest of transverse ridges. The distribution characteristics of grain size on coastal transverse ridge could be concluded as the finest and the best sorting sands distributed on the crest of coastal transverse ridge and the coarsest sands distributed at the leeward slope base, which is a new distribution model of grain size on dunes. The surface particle-size distribution model of the transverse ridge in Changli Golden Coast resulted from the combined effects of the alternation variation of the region's prevailing wind direction and strong wind direction and wind force difference as well as asymmetry on both sides of the dune. In which, the large height and asymmetrical dune shape were the main factors resulted in the distribution characteristics of grain size on coastal transverse ridge. The alternating variations of wind direction made the slope bases on both sides of the transverse ridge constantly in a coarsening state, but becoming finer and in the sorting state on the crest and both side slopes. The wind force difference strengthened the process and its degree above.

  • Earth Surface Processes
    ZHOU Nian-xing, HUANG Zhen-fang, LIN Zhen-shan
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    From the point view of landscape dynamic and its landscape ecological planning and construction of tourism area, research on the landscape spatial pattern changes and the effects of tourism and other human disturbances may have a significant academic meaning. Five remote sensing image data of 1977,1987,1998,2004 and 2007 have been used to analyze the landscape effects of tourism and other human disturbances in Wulingyuan World Heritage Site as a tourism destination. This article presents the dynamic change of landscape spatial pattern in 30 years. The results show that: (1) The landscape spatial pattern changed remarkably under the disturbances of tourism and other human activities from 1977 to 2007. The vegetation cover patch area grew dramatically, the agricultural landscape patch decreased gradually, and the built-up area fluctuated but mainly decreased. The fragmentation proved to be serious from 1977 to 1987, but to be alleviative from 1987 to 2004, however to be adversely aggravating since 2004. (2) The relationships between tourism development process and landscape spatial pattern have been outlined. The landscape proved to be more fragmental in the beginning of tourism exploration, and to be alleviated during the growing of tourism industry, but to be seriously fragmented in the tourism stability period. From the point of view of landscape diversity and dominance, the diversity will be reduced and the dominance will be prominent in the process of tourism development.(3) The influencing factors and their quantification on the landscape spatial pattern have also been presented. The agricultural cultivation, tourism activity and road construction have been diminished in turn.

  • Earth Surface Processes
    ZHANG Yue-cong, ZHAO Zhi-qiang, LI Shuang-cheng, MENG Xian-feng
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    To investigate dynamics of surface vegetation, and optimize regional land use structure and pattern, monthly and annual NDVI were computed respectively by using maximum value composites and average method with 10-day NDVI of SPOT-VEGETATION from Jan. 1999 to Dec. 2006, and then variation of surface vegetation cover and its temporal dependence were indicated by the slope of one-variable linear regression and Hurst exponent. The results show that the greening area is larger than the degraded area in the northern part of North China as an indicator of positive or negative slope of NDVI series. The greening area, stable area, and degraded area account for 66.04%, 14.39% and 19.57% of the total area respectively. The dynamics of surface vegetation cover shows significant regional differentiation. For example, vegetation cover would show the decrease trends in transitional zones among Hebei Province, Shanxi Province and Inner Mongolia Autonomous Region, while persistent increase of vegetation cover appears in the Taihang Mountain, Yanshan Mountain and Luliang Mountain. The fact that Hurst exponents of the NDVI time series greater than 0.5 suggests NDVI series are generally persistent and a rising tendency in the past will cause possible increase in the future. So, the variation of surface vegetation cover in cropland, woodland, and built-up area would show the increasing tendency, while grassland would appear a possible decrease. Moreover, dynamics of surface vegetation exhibits obvious difference in different land cover types. The stability of coniferous forest ecosystem is larger than the deciduous broadleaf forest and shrub vegetation, while the stability of grassland vegetation is lower than the forestland system. Influencing factors of vegetation cover such as temperature, precipitation and evaporation differ in different elevations, and so the stability of ecosystem variation presents altitude differences. To increase the sustainability of regional agro-forestry ecosystems, more natural factors should be considered above 1000 m, while much more attentions have to be paid to the anthropic factors below 1000 m in landuse planning according to the research results.

  • Earth Surface Processes
    HU De-yong, ZHAO Wen-ji, LI Xiao-juan, LI Jing, LI Jia-cun
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    Landslide hazard susceptibility relates to middle- and long- term predicting and forecasting, and it is very important to landslide managements. In the process of evaluation based on statistical model, the result is greatly influenced by landslide sample size, so the more conservative and less influencing model must be applied to the susceptibility evaluation in order to reduce the system error. The study area is located in Malaysia tropical rainforest, where nine factors were selected as topographic slope, aspect, surface curvature, geomorphology, lithology, structure, land cover, road and drainage and so on. The Landslide Hazard Susceptibility Index (LSI) was constructed based on support vector regression (SVR) theory, then the susceptibility evaluation methodology was discussed in incomplete sample conditions, and the relation between the sample size and the result accuracy was analysed too. The result show that the success-rate analysis accuracy based on SVR model was about 95.9%, an obviously high value; the fluctuation of sample size influenced the accuracy slightly; SVR was a better model suited to landslide hazard evaluation in high vegetation cover conditions, which could provide a technique support for landslide management in similar areas.

  • Climate and Global Change
  • Climate and Global Change
    ZHANG Yue-hong, WU Shao-hong, DAI Er-fu, YIN Yun-he, LIU Deng-wei
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    Climate change risk can be defined as the possibility of impacts on natural ecosystems and socio-economic systems resulted from or aggravated by climate change, particularly the negative aspects. Many disciplines, particularly Geography have been heavily involved in the scientific assessment of climate change and its potential social and environment impacts. However, it still needs to be studied further using more systematic methods of risk assessment and management, while appropriate risk categorization is their prerequisite and foundation. In this paper, we first identify the main risks induced from climate change by sectors, in which not only the traditional abrupt risks are included, but some "low-probability" events and creeping hazards are also contained. And then, these risks are categorized into four risk categories applying a new risk categorization system brought forward by Ortwin Renn in a framework of IRGC: first, we propose that uncertainty of the risk-related knowledge and information could be treated as the classifying criteria. Then, we use IPCC's quantitative terms of expressing uncertainties-confidence' and likelihood' as the feature parameters to construct membership function for the four categories respectively, and according to the maximum principle we identify the type that a certain risk should belong to. Given that not all impacts are assigned with confidence' and likelihood' in IPCC report, level of agreement & amount of evidence' is applied to form a qualitative classification method as a supplement. Thus a preliminary semi-quantitative risk categorization system for climate change has been established. Finally, the categorization results of climate change risks have been acquired. Thus, we can assess and manage climate change risks with different approaches and strategies, which will improve the efficiency of risk management, enhance the scientific nature in risk assessment and lay a good foundation for the integrated risk governance of climate change risks.

  • Climate and Global Change
    CUI Lin-li, SHI Jun, YANG Yin-ming, LI Gui-cai, FAN Wen-yi
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    With global climate change and rapid regional urbanization, temperature and eco-environment changed significantly in the Yangtze River Delta. Based on regional meteorological data from basic/reference climatological surface stations and population data, annual and seasonal temperature change characteristics, the difference of temperature change in big cities, middle cities and small towns, and the urbanization warming and its relative contribution to the total amounts of temperature change was analyzed covering the periods from 1959 to 2005 and from 1981 to 2005. The result indicates that in the past 47 years and 25 years, annual mean temperature, annual mean maximum and minimum temperature increased significantly, with the highest warming rate in winter and spring, and the lowest warming rate in summer. For all types of stations, the annual and seasonal mean temperature, mean maximum and minimum temperature generally increased in the two periods of time. The warming rate in big cities was significantly higher than that in middle cities and small towns, and urbanization warming was almost in annual and seasonal temperature in big cities. The warming rate of urbanization and its relative contribution to the total amounts of temperature change was highest in mean minimum temperature, and lowest in mean maximum temperature. From 1959 to 2005, the warming rate in small towns was close to that in middle cities, and the influence of urbanization on the temperature in middle cities was small, but from 1981 to 2005, the warming rate in middle cities was higher than that in small towns, and the warming rate of urbanization for middle cities was significant. In the Yangtze River Delta, the changing trend and warming rate of temperature, the warming rate of urbanization and its relative contribution to the total amounts of temperature change were basically consistent with that in other places. Causes for the differences between our result and those found by other researchers are likely to be related to regional extent, the criteria for defining urban and contrasting stations, the different influence of urbanization on the contrasting stations, station network density, analytical methods, time periods, and etc.

  • Climate and Global Change
    JIANG Zhi-hong, ZHANG Xia, WANG Ji
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    Using the outputs as simulated by 13 GCM models provided by the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC-AR4), the situation of climate change in China in the future 100 years under SRES A2,A1B and B1 greenhouse gas is analyzed. We analyzed linear tendency,time series and annual changes of temperature and precipitation in all scenarios. The results show that the climate in China has a warming and wetting tendency in the 21st century. The range of temperature changes is from 1.6℃~5℃, the mean warming is 3.5℃, and precipitation is from 1.5%~20% with a mean of 7.5%. Considering the effect of SRES A2, A1B and B1, the temperature in China would be increased by 5.3℃, 4.3℃ and 2.8℃ respectively at the end of the 21st century. The precipitation would be increased by 11%, 9.6% and 6.4% at the end of 21st century . The largest range of warming is in winter, while the increase of precipitation is larger in winter and spring. The distributions of the mean temperature and precipitation in China were analyzed in this paper. The results indicated that the distributions of temperature are almost similar in all the scenarios, the warming over the northern part is greater than that in the southern part of China, but the warmest scenario is A2. The warmest area is in plateau, the second is near northeast and northwest of China, the other areas will increase from southeast to northwest gradually. And the distributions of precipitation are almost similar in all the scenarios too. The distribution of increased precipitation in China is also in the northern part of China.Precipitation increases obviously in North, Northwest and Northeast China, and increase in the region south of the Yangtze River. Compared with results of Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC-TAR), differences among models supplied by IPCC-AR4 have been obviously reduced. The ensemble standard deviation of different models suggests that the uncertainty of the projected climate changes over China in the 21st century has been improved. But the resolution of GCM is still low currently, we could consider other methods, such as downscaling (dynamic or statistic), then estimate area climate changes in the future.

  • Hydrology and Water Resources
  • Hydrology and Water Resources
    SHI Chang-xing
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    Scaling effects on sediment yield in the upper Yangtze River are investigated through constructing relationships between the specific sediment yield (SSY) and drainage area and factors influencing soil erosion based on data of drainage basins upstream of 268 hydrological stations. The factors influencing soil erosion used in the study are those in the Revised Universal Soil Loss Equation (RUSLE) and are calculated from DEM, rainfall, landuse, soil type data banks for the upper Yangtze River. Results show that there is a negative power relationship between SSY and the drainage area of all the gauged drainage basins in the upper Yangtze River and this relationship can be ascribed to the changes in rainfall erosivity factor R and soil erodibility factor K in RUSLE with the drainage area. Between the drainage area of 104-1.58×105km2 exists an abrupt decline of SSY with the increase of drainage area and it is a main component of the overall decreasing trend of SSY with the drainage area. In the regression relationship of SSY with the drainage area and all RUSLE factors, SSY is positively and exponentially related with the drainage area, revealing that deposition of eroded sediment occurs in a short distance in the upper Yangtze River. The relationships of SSY with the drainage area and RUSLE factors of the drainage basins of the main first-order tributaries of the upper Yangtze River are also constructed and analyzed. The results show different relationships for different tributaries because of different reasons. The scaling effects on sediment yield and causes for changes in SSY with the drainage area in the Jingsha basin are similar to those in the whole upper Yangtze River. The causes for changes in SSY with the drainage area in the Min-Tuo (Minjiang-Tuojiang) basin are also associated to the changes in factors R and K with the drainage area, but SSY is negatively related with the drainage area in the multiple regression relationship between SSY and the drainage area and factors in RUSLE due to sediment deposition in the lower reaches of the tributary. In the Jialing basin, the main factors for the occurrence of the positive relationship between SSY and the drainage area are the slope length and steepness factor LS and support practice factor P, and the positive relationship between SSY and the drainage area also keeps in the multiple regression between SSY and factors in RUSLE and the drainage area. There is not a significant regression relationship between SSY and the drainage area in the Wu-Chishui-Heng (Wujiang-Chishui-Hengjiang) basins due to intensive human activities.

  • Hydrology and Water Resources
    WANG Sui-ji, RAN Li-shan
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    The mean annual discharge, sediment concentration and sediment delivery ratio in the period from 1970 to 1989 are evidently smaller than that in the period from 1954 to 1970. The relations between monthly mean discharge and sediment concentration are different comparing the two periods of time. These phenomena have been influenced by human activities in which the dam building has been the dominant factor since 1970. To discuss the dam effect on decrease of sediment yield a concept of efficient area of dams was advanced. The relation between the annual efficient area of dams and years was fitted. The results show that the varying trend of the relation curve is coincident with the variation of the sediment yield in the decade's distribution. Since 1990 the increase of the sediment yield has resulted in evident decrease of the efficient area of the dams in the Wudinghe River basin. It is necessary to build dam largely and rapidly for restraining the increase of sediment yield in the river basin. If we want the annual sediment yield in the river basin gradually decrease, the annual efficient area of dams must be gradually increased year by year.

  • Hydrology and Water Resources
    CHEN Ying, XU You-peng, YIN Yi-xing, LIU Xing-cai
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    The hydrologic process is a very complicated nonlinear system, of which runoff is a very significant component.Single parameter is difficult to characterize the change in the daily runoff time series completely, while the multifractality method with singular spectrum analysis enables us to get more information about the nonlinear behavior of runoff. Based on long-term daily runoff records of Cuntan, Yichang and Datong stations, this article has studied the multifractal temporal scaling properties of the Yangtze River, and fitted the multifractal spectrum by the modified version of the multiplicative cascade model.The results revealed that (1) The discharge series of the Yangtze River is a similar multifractal, and the mulfiractality is caused by the long-term persistence.The long-term persistence of daily runoff may be related to the interactions between precipitation and underlying surface over various ranges of space-time scales. (2) The fits based on universal multifractal model describe well the scaling behavior of positive as well as negative moments in the 3 daily runoff records . The two parameters a and b obtained from the model can be used to calculate the width Δα of singularity spectrum, and the values of a, b and Δα can be regarded as 'fingerprints’ for each station, which can be served as an efficient test for the state-of-the-art precipitation-runoff models. (3) The comparison of the width Δα of singularity spectrum among these three stations revealed that there are spatial differences in the complexity of the daily runoff change on the Yangtze River. The complexity of runoff records on Datong is larger than those of the upper reaches of the Yangtze River, while there is no significant difference between Cuntan and Yichang. The factors contributed to the complexity include the drainage area, constitution of water quantity, the characteristics of precipitation and underlying sufrace, and so on.

  • Environment and Ecology
  • Environment and Ecology
    XU Xin-liang, LIU Ji-yuan, SHAO Quan-qin, FAN Jiang-wen
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    Supported by MSS images in the mid and late 1970s, TM images in the early 1990s and TM/ETM images in 2004, the spatial distribution data set of ecosystem types was acquired through analysis and distinguishment, then the dynamic changes of spatial pattern and structure of ecosystems in the Three-River Headwaters region were analyzed since the 1970s. The results showed that alpine grassland occupied the largest area in the Three-River Headwaters region, and the area of alpine grassland occupied 64.68% of the total land area and 99.58% of the total grassland area.Wetland, glacier and mountain permanent snow-cover were characteristic ecosystems in the Three-River Headwaters region, with marsh area occupying 26.09% of the total area of water and wetland ecosystem, and glacier and mountain permanent snow-cover area 9.02% of the total area of water and wetland ecosystem. As the characteristic ecosystems in the Three-River Headwaters region, wetland, glacier and mountain permanent snow-cover played important roles in providing stable water resource. During recent 30 years, the changes of ecosystem spatial pattern in the Three-River Headwaters region have been stable and rather slow, with an annual changing rate of farmland, forest, grassland, water and wetland, and hungriness ecosystem being less than 0.5% respectively, the least but stable in the Yangtze and Yellow river basins, even the whole country. The changes of grassland, water and wetland ecosystem have occupied a dominant position in the Three-River Headwaters region since the mid and late 1970s. The changes of grassland mainly occurred in the central and eastern parts of the region, dominated by reclamation of grassland and conversion of grassland into unused land such as bare land, sandy and salt land. And the changes of water and wetland ecosystem mainly occurred in the vast western and northern parts of the region, represented by conversion of water body into beach land and conversion of wetland into grassland.

  • Environment and Ecology
    JIANG Qun-ou, DENG Xiang-zheng, ZHAN Jin-yan, LIU Xing-quan
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    Land use changes influence the distribution and structure of terrestrial ecosystems, and also change their carbon storage. Cultivated land, an important part of our country, affects not only the crop productivity, but also the spatial distribution pattern of vegetation carbon storage. According to the GLO-PEM model and by using the NOAA/AVHRR data acquired in 1988, this paper estimates the net primary productivity of the Huang-Huai-Hai Plain. Then the amounts of the vegetation carbon storage associated with the various land uses are estimated by subtracting the quantities of litter. The key findings show that there are differences in vegetation carbon storage among the various land uses and over space. The density of vegetation carbon storage in forest area is the biggest, and the smallest is the unused land. According to the decoded land use information from Landsat TM/ETM digital imagines, we traced the land conversions in the period between 1988 and 2000 and analyzed the changes between cultivated land and other land types and find it interesting that different land types can be transferred to each other. But the net change will be various. With the development of economy, built-up area gradually expanded, and the amount of cultivated land around the city were occupied. A total of 5.3 107hm2 of land were transferred to cultivated land in the Huang-Huai-Hai Plain. Based on the above data, we calculated the impacts of cultivated land conversions on the vegetation carbon storage. It is found out that that the vegetation carbon storage decreased by 0.25% due to the land conversions between cultivated land and other land uses. The cultivated land conversion to built-up area caused a decrease of 4.57 103tC released to air. We overlapped the agro-ecological zones and the vegetation carbon storage, and calculated the total changes in every agro-ecological zone. The vegetation carbon storage of the Huang-Hai Plain decreased by 0.89 103t. With the population increase, 59% of the cultivated land was transferred to residential area. This is the main reason for the substantial decrease in the vegetation carbon storage. The research results provide valuable information for the formulating of the carbon management policies at a regional extent.

  • Environment and Ecology
    YU Jie, LIU Min, XU Shi-yuan, HOU Li-jun, OU Dong-ni, CHENG Shu-bo
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    Changjiang Estuary, as a typical transitional zone between land and ocean, receives large quantity of organic materials from the Yangtze River and the ocean. In addition, the input of local materials such as detritus of macrophytes, photoplankton and benthic organisms makes it more complicated to trace the source and fate of organic matter in the estuarine and coastal tidal flat. The objective of this study is to trace the potential source of organic matter and the contribution of local environment to the organic materials by investigating the stable carbon isotopes in the organic constituents from the southern tidal flats of Changjiang Estuary. According to the features of physical geographical environment and the discrepancy in the effects of human activities in the study area, 9 typical sampling stations were selected along the southern Changjiang estuarine and coastal line. By measuring the stable carbon isotopes of organic matter in the winter (February 2006) and summer (August 2006) seasons of low and relatively high discharge, we analyzed the probable sources of organic matter from suspended particles and surface sediment. It is found that the ratios of stable carbon isotope in SPOM were respectively -25.8 ~-23.4‰ and -25.1‰~-22.9‰ in February and August, with the character of more negative in February. The spatial change of carbon isotopes displayed the trend of more positive in salt water than in freshwater areas, suggesting the mixture of marine and riverine organic matter. Due to the seasonal change of water discharge and marine phytoplankton blooming, terrigenous inputs exceeded marine inputs in winter and the reverse results have been found in summer. The ratios of stable carbon isotope in surface sediment ranged from -25.0 to -20.4 and -24.7 to -19.5 respectively in February and August. There was no obvious seasonal difference observed in isotopic compositions and the spatial change was similar to SPOM, suggesting the OM in sediment coming from the deposition of suspended particles. However, the autochthonous materials had also certain influence on the stable carbon isotopic compositions in organic matter. The input of sewage and tributary water impacted the carbon isotope in SPOM while the buried marsh macrophytes and benthic microalgaes contributed to the sedimentary organic matter.

  • Environment and Ecology
    ZOU Xiao-jin, QIU Rong-liang, ZHOU Xiao-yong, HUANG Sui-hong
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    Vegetables have been reported as an important route of human exposure to heavy metals. This study aims to evaluate the health risks associated with ingesting heavy metals through vegetables for the general population of four districts (Shangba, Xiaba, Suoyikeng and Hewu) which were contaminated by mine exploiting and acid mine drainage irrigating in Dabao Mountain, Guangdong province, China. Soil samples (36), irrigative water (32) and vegetable samples (120) were collected from the 4 districts and heavy metals analyzed by atomic absorption spectrometry (AAS). The mean concentrations of Pb, Zn, Cd and Cu of the soils in Shangba village were 843.7, 2112.0, 2.66 and 586.3 mg/kg, respectively, and were 3.8, 10.6, 8.9 and 11.7 times compared to the tolerant limit level in China. The vegetable concentrations in Shangba village were 4.0, 1.1 and 5.6 times of the tolerant limit level of vegetables in China. While the mean concentrations of Pb and Cd in the other three districts were also higher than the tolerant limit level of vegetables in China. The heavy metal concentrations of soil and irrigation water and vegetables in the 4 districts were in the order: Shangba>Xiaba>Suoyikeng>Hewu. The average daily intakes (DI) of Pb and Cd in Shangba were 0.28 and 0.097 mg/d, which were 1.40 and 1.35 times of the provisional tolerable daily intake (PTDI) established by FAO/WHO. While the DIs of Zn and Cu in Shangba were below the PTDI. The DIs of heavy metals in the other three districts were also below the PTDI. The target hazard quotients (THQs) can be used to evaluate the health risks with heavy metals by vegetable concentrations consumed in inhabitants. The THQ of heavy metals of vegetables in Hewu and Suoyikeng were below 1, while the Pb and Cd in Shangba were more than 1, indicating that Pb and Cd were the key heavy metals which affected health risk of the inhabitants in this polluted area. It also showed that the inhabitants who lived near the contaminated river faced the adverse health risk. It indicated that health risk was caused mainly by AMD irrigating. Shangba villagers had higher health risk because they irrigated heavily contaminated water from Hengshi river, while Hewu villagers had less health risk by using contaminated water for irrigation. The THQ of Cd of Shangba village through vegetables was similar to that of Taiwan through oyster, while the THQ of Zn and Cu were lower than that. The THQ of heavy metals in Hewu was similar to those of uncontaminated areas.

  • Economy and Regional Development
  • Economy and Regional Development
    ZHANG Lei, ZHU Shou-xian
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    Urbanization can be referred to as a process by which both human activities and productive factors concentrated from rural areas urban areas. As a result,modern cities act as the central places for human-being,not only in settlements and material consumptions,but also in social productions and environmental pollutions.Therefore,the changing patterns of agglomeration both in demography(which can be named as the demographic-urbanization)and in economy(which can be titled as the economic-urbanization)should be the two essential criteria for measuring national or regional urbanization,rather than the only one in demography.The findings,based upon the modern urbanization movement of 12 countries,including China,are salutary. First,development speed of economic-urbanization in all the countries is faster than that of demographic-urbanization. Second, but more important,as the role of secondary industry in modern urbanization process is going to be weakened,the influences of tertiary industry on modern urbanization is getting greater and greater. By contrary,the structural change oriented to the development of the secondary industry rather than that of the tertiary could be the major reason for a widening gap between economic- and demographic-urbanization in China.

  • Economy and Regional Development
    SUN Tie-shan, LU Ming-hua, LI Guo-ping
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    This study identifies the national benchmark industrial clusters, including both manufacturing and non-manufacturing clusters, using the 2002 national input-output table of China. A set of 22 industrial clusters are derived through combining an algorithm for defining a strength-of-linkage measure for all pairs of input-output sectors with application of a standard clustering algorithm. The national benchmark industrial clusters can be used as cluster templates in subsequent regional analysis. In this study, the template clusters are used to analyze the manufacturing sector of Beijing, and particular attention is focused on the electronic and telecommunication equipment cluster of Beijing. We find that there are three relatively large and highly specialized manufacturing clusters in Beijing, which are electronic and telecommunication equipment cluster, motor vehicles and equipment cluster, and electronic component and device cluster. For the electronic and telecommunication equipment cluster, Beijing is highly specialized in telecommunication equipment production and other electronic and telecommunication equipment production sectors. The spatial analysis shows that the electronic and telecommunication equipment cluster of Beijing is highly concentrated in the suburban area, mostly in Chaoyang, Haidian and Daxing districts.

  • Economy and Regional Development
    HU Wen-hai
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    Central China, including Shanxi, Henan, Anhui, Jiangxi, Hubei and Hunan, is the country’s major food production area. This paper analyzes its grain production scales from grain sown area and grain output. By surplus method, it explores fluctuation of grain production and its characteristics with time sequence data of 1978~2006 grain production. First, the fluctuation is a classical one, which fluctuates in the increase and decrease of total grain production, second, it is a short period fluctuation which takes place in 2~3 years, third, except few years, the fluctuation is within 5%. Meanwhile gray interrelated mode is established with gray systematic theory to analyze the influentiing factors of grain comprehensive productive capacity. Irrigation area, grain sown area and disaster stricken area are the major influentiing factors. Based on the characteristics of grain production in Central China, the paper analyzes its influence on China’s grain safety: first, since 1978, Central China’s grain production has been increasing by 2.12% per year; second, Central China’ grain production occupies 30% of average national grain production which has an objective impact on China grain production; third, Central China’s grain production fluctuates to a certain degree but not so much; and fourth, gray interrelated mode indicates irrigation area, grain sown area and disaster stricken area are the major influentiing elements for grain comprehensive productive capacity. Effective regulation and control measures can promote grain production and guarantee China’s grain safety. First of all, the function and status of a commodity grain production base cannot be changed in the central part, and the protection of farmland and agricultural infrastructure should be strengthened; second, stabilizing the current policies and measures, constructing a long-term system to support national grain production, and maintaining and upgrading farmers' initiative; and third, bringing into full play scientific technology and innovation.

  • Urban and Rural Studies
  • Urban and Rural Studies
    CHAI Yan-wei, WENG Gui-lan, SHEN Jie
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    With the launch of system reform since the late 1970s, the urban commercial space went through great changes but with less comprehensive researches. Since the increasingly important influence from the consumers on the system is usually ignored by previous relative papers, the purpose of this paper is to explore the evolution of the central place system from the point view of the corresponding changes of residents' shopping behavior. Taking Shanghai as the city of case study, the research collected the information of residents' daily shopping activities by questionnaire survey which provided the data base. The spatial characteristics of the residents' shopping activity on the aggregate level are generalized, and then further examined by modeling the spatial structure of shopping trip of different commodities; finally, the eight surveyed communities were grouped into three regions according to the income of residents and their spatial structure of residents' shopping activity was explored respectively to see the sub-system shopping centers of different socio-economic areas. The results conform again the hierarchy of shopping trip space of different commodities in previous researches; what's more, it is also found that the condensation of the spatial structure of shopping trip has showed up, which is a reflection of the change of urban commercial system. For the analysis of last part, a hierarchical model of spatial structure much like Davies' "development and hierarchical sub-system shopping centers" is identified. However, we believe that its formation is actually a result of low income residents’ moving out and the underdevelopment of the suburban local commence, which is quite different from that of western cities.

  • Urban and Rural Studies
    SU Fei, ZHANG Ping-yu, LI He
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    Coal-mining cities are confronted with a lot of serious social, economic and eco-environmental problems.Though extensive research on coal-mining cities are from many relevant disciplines, few are from the coupled human-environment system.There are obvious socio-economic and eco-environmental vulnerability characteristics on coal-mining cities.Vulnerability analysis framework in sustainability science has many properties of multi-scale, multi-element, multi-flow and multi-cycle, which presents a new research paradigm for coal-mining city.Based on a detailed discussion about the conception of economic system vulnerability (ESV), the essay establishes an economic vulnerability assessment model of coal-mining cities from the aspects of exposure-sensitive to and response capacity for the gradual depletion of the regional minable coal resources.The conditions of minable resources, industrial and employment structures, which determine their exposure-sensitivity to the depletion of regional minable coal resources, create an exposure-sensitivity index.From the angles of urban economic strength, industrial state, regional and infrastructure conditions, the degree to open up and economic conditions of urban and rural residents, it constructs a coping capacity index.According to the model, the economic system vulnerability of 25 typical coal-mining cities is evaluated and divided into three categories by principal components analysis.The results show that economic system vulnerability of coal-mining cities differs significantly in different development stages, city sizes and regions.The ESV of old coal-mining cities is generally high; the ESV of middle-aged is almost in 3 vulnerability grades, especially concentrated on medium grade; the ESV of young is low.The ESV of coal-mining cities presents obvious regional differences, including north to south and east to west.The high economic system vulnerability of coal-mining cities mainly concentrates on Northeast China.The average score of ESV shows a trend of Northeast>Central>West>East.The ESV of southern coal-mining cities is medium, while the northern region is distributed in three grades.The ESV of different size coal-mining cities shows a trend of big cities>medium-sized cities>mega-cities>small cities.The study provides some lessons for the vulnerability assessment of other subsystems and human-environment coupled system, and also gives a basis for relevant departments to adopt some policies for economic transformation.

  • Urban and Rural Studies
    SONG Wei, LI Xiu-wei, XIU Chun-liang
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    The patterns of spatial interaction and hierarchical structure of Chinese cities have been both shaped by and reflected in the air traffic pattern as air transport industry developed rapidly since the 1990s. Air passenger linkages or traffic flows among cities are used as the basis for identifying hierarchical status of cities-a theme of long-standing concern for analysis in spatial organization. Three specific research areas are addressed in this paper: (1) the spatial structure of intercity air passenger flows; (2) the pattern and hierarchical standing of major Chinese cities in domestic passenger air transport-based spatial interaction; and (3) air passenger dominance and changing urban system structure. Fifty-seven major Chinese cities with scheduled passenger flights and substantial passenger turnovers are included in the study. Principle of dominant flow, or Nystuen-Dacey method, along with Hierarchical Cluster Analysis by squared Euclidean distance, is applied to intercity air passenger data of 1995, 2000, and 2003. This study reveals, first, that directional intercity air routes and interactions are strongly dominated by cities in the East, where the trio of Beijing, Shanghai and Guangzhou-Shenzhen constitutes the backbone of the national air transport network. Cities in the Middle Region lag behind their counterparts in the other two regions in terms of air network importance. Second, measured by dominant (first-order) air passenger flows, a highly concentrated hierarchical system of passenger air transport and spatial organization of cities has evolved in the form of the control of three top-ranked, national command and control centers from 1995 to 2003. Third, under the national hierarchy led by Beijing, Shanghai, and Guangzhou-Shenzhen, the regional and provincial significance of such cities as Chengdu, Xi'an, Kunming, Xiamen and Urumqi is also evident. Fourth, it seems that the hierarchical nature of the patterns of intercity linkages is increasing. The expansion of China's regional airlines and the probable development of the hub-and-spoke network system have the potential to promote further hierarchical connections and organization in China's national air transport network and urban system.

  • Urban and Rural Studies
    ZHANG Min, ZHEN Feng, ZHANG Xiao-ming
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    Theories concerned with peri-urbanization were reviewed, including the basic concept about the peri-urbanization and peri-urbanized areas, the spatial turn of research realm, the different mechanisms of the peri-urbanization in several typical regions, and the characteristics and the evolvement process of peri-urbanization phenomenon occurring in the coastal region of China. Then, the paper takes the urban fringe area of Putian City in Fujian Province as a case, where the phenomenon of peri-urbanization arises even though the economy is not as developed as many other areas in the coastal region of China, especially the Yangtze River Delta and the Pearl River Delta. Based on the survey on the population, land-use pattern and infrastructures of 309 villages in the urban fringe area of Putian, the paper puts forward the characteristics and the mechanisms of the peri-urbanization taking place in such relatively less developed areas of the coastal region in China.The characteristics of the peri-urbanization in Putian can be concluded in three points: (1) As well as high population density and high non-agriculture rates, the fluidity of population is notable. Unlike the developed area where a great many people are floating from other areas, Putian's population has high rate of both floating in and floating out. (2) The built-up area blends with agricultural area, and the industrial area invades the village. Unlike other peri-urbanized areas where industry buildings are the leading actor, the dwelling house is the main component of the landscape in Putian, which suggests that the peri-urbanization would be mostly recognized on its constructing landscape rather than the functional shifting. (3) The improvement of infrastructure is mainly influenced by the radiation from downtown, hence the modernization of the villagers' living condition is degressive as the distance from downtown increases. The main reasons can explain the forenamed characteristics as follows: (1) Conflict between the population and the land resources is the essential dynamics of the peri-urbanization. (2) Folk capital and moderate-small enterprises, not the foreign investment and large enterprises, act as the main impetus of such less developed peri-urbanization area. (3) Due to the weak central city, the actual city area is smaller than the municipal administrative boundary, and the dual land system of urban and rural exists widely on the fringe of the city. (4) The special culture of strong ancestrial idea and being inclined to parade the wealth advances the symbolization of the dwell house, and the large luxurious house acts as the main body of the landscape.

  • Urban and Rural Studies
    ZHANG Jian, PU Li-jie
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    The triangle method, as an intuitive platform for illustrating sustainability status and trends in economic development, seems to hold promise as an analytical management tool liable to be used by researchers and policy-makers at different levels due to its simplicity and flexibility.Based on the interrelationships among economic development, resource-energy consumption, and environmental pollution, in conjunction with the ecological performance and the triangle method, a definition to sustainable economic development was proposed, and a novel triangle method was designed to evaluate economic development sustainability. This paper selected Chongzuo City, a newly-established frontier trade city in western China, as a research region. Chongzuo City is located in the western zone among the country's three major zones of the eastern zone, middle zone and western zone. It had a total population of 2.3065 million in 2005. It covers a total area of 1.7345million hm2 with five counties, one city and one district under its jurisdiction. As a case study, the triangle method was applied to assess the sustainability status and long-term trends of Chongzuo's integrated sustainability development. The results show that the integrated sustainability development in 2005 represents a relatively common state of sustainability, and the seven administrative sub-units in Chongzuo City reflect sustainability positions ranging from weak sustainability, strong sustainability to common sustainability. The sustainability in the southeastern part is better than in the northwestern. The Chongzuo's integrated sustainable development revealed a common sustainable trend during 1985-1990, a strong sustainable trend during 1991-1995, a common sustainable trend during 1996-2000, and a common sustainable trend during 2001-2005, but is lower than the former stage. Chongzuo's unremitting efforts in environmental protection and in the increasing integration of the environmental considerations within the economic development process over the last twenty years are contributory to these status and trends.

  • Culture and Tourism
  • Culture and Tourism
    YANG Zhao, LU Lin
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    Recently a new phenomenon of population migration based on mass tourism-tourism migration-has been highly concerned by foreign scholars. In China, though this phenomenon has emerged and is progressing, little importance is attached. In the West, verification analysis is emphasized in the research of tourism migration, which finds expression in the discussion of the relationship between tourism and migration, while leaving the vacancy of the definition of this phenomenon as well as its research system. Based on of analysis the related foreign literature and verification researches, the author defines the concept of tourism migration which is classified into two types of tourism labor migration and tourism consumption migration, and further subdivides the former into entrepreneurial migration and employment migration and the latter into lifestyle migration and tourism retirement migration. And three researching aspects about tourism migration are confirmed: first, behavioral theoretic researches, covering the contents such as demographic features of tourism migration groups, type divisions, behavioral rules, psychological perception and self-cognition; second, motivational theoretic researches, including those on dynamic factors, dynamic mechanism, migration policies and social networks; and third, social impacts researches, with the focus on the culture assimilation and conflict, the impacts on the local area, the evolution and management of the destination and the VFR tourism. Moreover, the central contents of the three aspects are interpreted and eventually the research system of tourism migration is constructed. Finally, proceeding from foreign studies and personal researches, the author puts forward some referential theories such as migratory dynamics, praxiology, sociology, as well as some material study methods such as qualitative methods, quantitative methods and comparative research, long-term station observation, case study and some aspects that need further attention. These studies have preliminarily discussed Chinese tourism migration in theory and methods.

  • Culture and Tourism
    LI Dong-he, ZHANG Jie, ZHANG Shang-zheng, FANG Chao
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    Residents' perceptions and attitudes to tourism impacts have been a hot study issue of both tourism geography and tourism sociology. In foreign tourism studies, the distance between the residents' habitations and tourists' attractions has been taken as a main factor in explaining the differences of residents' perceptions and attitudes to tourism impacts. However, similar studies are not found in domestic literatures in China. Considering the above conditions, taking Huangshan Scenic Area as an example, with the aid of questionnaire survey, using techniques of SPSS and Arc View GIS, spatial differentiation of residents' perceptions and attitudes to tourism impacts bought by Huangshan Scenic Area are revealed. The results indicate that residents in the hinterland of Huangshan Scenic Area show evident spatial differentiation of their perceptions and attitudes to tourism impacts brought by Huangshan Scenic Area. In determinate spatial scale, the intensity of residents perceptions and attitudes to positive tourism impacts wane and negative tourism impacts augment as the distance increases; in a more extensive space, affected by its tourism spatial structure and enclave tourism mode, the spatial differentiations of residents' perceptions and attitudes to tourism impacts brought by Huangshan Scenic Area take on "W-shaped" structure and "M-shaped" structure to positive tourism impacts and negative tourism impacts respectively. Also, the forming mechanisms leading to the above differentiation rules of residents' perceptions and attitudes to tourism impacts were analyzed, which are residents' knowledge of the scenic area, acting mechanism of tourist flows, transportation routes and residents' response to tourism development. It is thought that we can't oversimply deduce that the residents' perceptions and attitudes are "distance decay" or "distance increase". The tourism spatial structure and its subsequent effect should be taken into account when we analyze the spatial differentiation of residents' perceptions and attitudes to tourism impacts. The aim of this study is to reveal the spatial differentiation of tourism impacts, so as to offer some guidelines in optimizing regional tourism benefit and making community-oriented humanism regional tourism development strategies.