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  • 2013 Volume 32 Issue 2
    Published: 10 February 2013
      

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  • Article
    CHEN Qiong, CAI Yunlong
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    Some social contradictions are aroused from the rural-urban conversion of farmland. Farmers lost land and have to adapt to the new way of life. So it is important to find the root problem from the view of the farmers. The Participatory Rural Appraisal is a good method to know the farmers' living condition and was applied to this study in the rural area around Xining city, Qinghai, China. Five sample villages were selected based on development period divided into three groups: urbanized village with location adjacent to urban, suburban and out suburban areas. The former two groups belong to early suburban development zone involving four villages. The latter group is recent outer suburban development zone involving one village. There are altogether 190 farmer households in five sample villages. We investigated them randomly. By analyzing the basic understanding and perception on economic value, social value and environmental value of farmland rural-urban conversion, this paper attempts to find the deep root of social problems and to put forward some advice for the regional land use and sustainable development. The results show that: the farmers' perceptions on non-agricultural conversion are mainly affected by per capita farmland, land development, distance from city. Their perceptions are basically consistent with the reality, which can be explained reasonably. Therefore, landless farmers make decisions rationally and know value of farmland urban-rural conversion. After expropriation, farmers generally have perceptions of increasing living cost, insufficient living guarantee and old-age security, and decreasing employment and income. The expansion of built-up lands and the improvement of infrastructures are decreasing transportation cost and pushing land price up. The farmers' value perception of farmland rural-urban conversion varies with location condition and with the biggest pressure perceived in the suburban areas. Urbanized farmers have the highest social value perception on rural-urban conversion due to the fact that earlier expropriation makes them get used to city life; suburban farmers' perceptions on that concentrate on increasing living cost, weakening living guarantee and land appreciation, because they are geographically oppressed by city and country; Out suburban farmers are eager to become citizens and hope to increase income by working in cities.
  • Article
    YIN Feihu, GAO Zhijian, XIE Zongming, LIU Changyong LI Xiaolan, LI Quansheng, LIU Yu
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    To illuminate influence of elevated CO2 and nitrogen supply on cotton field properties and microbial flora in the plot experiment, this study investigated organic carbon, total nitrogen, bicarbonate ion, pH, total salt and soil bacteria, soil fungi, soil actinomycetes under ambient CO2(360 μmol·mol-1) and elevated CO2 (540 and 720 μmol·mol-1) at 4 nitrogen levels (0, 150, 300 and 400 kgN/hm2). The results showed that, organic carbon, total nitrogen and pH at a soil depth of 0-40 cm tended to decrease elevated CO2(720 μmol·mol-1) at different nitrogen levels, but less effects on soil bicarbonate ion and total salt were found. Both bacteria population at a soil depth of 0-40 cm and actinomycetes population at 0-20 cm were enlarged, but fungi population at 20-40 cm soil depth tended to decrease under elevated CO2 concentration (540 and 720 μmol·mol-1) at different nitrogen levels.
  • Article
    DING Jianli, QU Juan, SUN Yongmeng, ZHANG Yongfu
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    Soil salinization is one of the major causes for soil desertification and ecological degradation in arid region. Acquiring large-scale and high-precision soil salinization information in real or near-real time is critical for preventing and mitigating soil salinization. The study area is located in Weigan-Kuqa oasis on the northern margin of the Tarim Basin. By analyzing Landsat-TM satellite image and soil samples obtained from field survey, we intend to investigate the relationship between Wet Index (WI) and Modified Soil-adjusted Vegetation Index (MSAVI). These two indices are often regarded as very important land cover biophysical parameters that are strongly descriptive of soil salinization in a certain degree. The study proposes a concept of MSAVI-WI feature space and builds a soil salinity monitoring index (MWI) model based on the analysis. The results indicate that there is a strong correlation between the MWI and surface soil salinity (with an R-squared of 0.844). Monitoring soil salinization with MWI is more precise than the salt indexes commonly used in traditional remote sensing monitoring methods. Difference matrix analysis also suggests that MWI detects different degrees of soil salinity and the changes of different combination of the vegetation and soil moisture better in the study area. Additionally, this index has a clear biophysical meaning that is often well accepted and understood. The study suggests that MWI will be helpful to monitor and evaluate soil salinization in arid region on large scale.
  • Article
    LI Xudong
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    The Wumeng mountainous areas of Guizhou are one of the largest poverty-stricken belts in China. With the development of social economy and the increase of population, the problems concerning population, resources and environment have been increasingly serious, which has greatly influenced and obstructed sustainable development in this region. The ideas and research methods about the relative carrying capacity of resources were used in this paper. The spatial-temporal dynamic simulation of relative carrying capacity of natural, economic resources, living standard and synthetic capacity was computed in Wumeng mountainous areas based on the statistical data during the period 1995-2006. The results are as follows: (1) Population has been severely overloaded in this region. (2) Land is the main resource which can carry population. (3) Carrying capacity of economic resources and living standards need to be enhanced. (4) The difference among the carrying capacity of the different parts of Wumeng mountainous areas was obvious. (5) Most of the synthetic carrying capacity at county level is in an overload condition. The results are of significance to understand the law of change of carrying capacity of resources, and to identify the main restraining factors of economic development in this region, and to implement the strategy for regional sustainable development.
  • Article
    LIU Bintao, TAO Heping, SONG Chunfeng, GUO Bing, SHI Zhan, ZHANG Chao, KONG Bo, HE Bing
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    Soil erosion is one of the most important environmental concerns of China. It is shown that rainfall erosivity is prone to cause severe soil loss, so it is used as a primary input parameter for soil erosion, sediment yield and water quality modelling. Based on the daily rainfall data from 590 meteorological stations in China from 1960 to 2009, rainfall erosivity was estimated and the temporal and spatial distribution was analysed with trend coefficient, climate tendency rate and the ordinary kringing methods with the aid of ArcGIS 9.2 software, respectively. The results show that the spatial distribution of rainfall erosivity has a decreasing trend from the southeast coastal regions to the northwest inland regions. The spatial distribution of average annual rainfall erosivity is similar to that of average annual precipitation. There is a slight increase of annual rainfall erosivity in most parts of China. There are four areas whose annual rainfall erosivity has a significant increasing trend and two areas with a significant decreasing trend in the 50 years. There are 59 stations whose coefficients of tendency pass the confidence test with 5% level of significance, and these stations are mainly located in the eastern and central Qinghai-Tibet Plateau, Tianshan Mountains and the southeast coastal regions. The areas of Numuhong, Dulan, Qumalai and Wudaoliang in Qinghai Province see the most significant increase from 1960 to 2009 throughout China, indicating that soil loss might be aggregated by rainfall increase in the headwaters of the Yangtze River and Yellow River.
  • Article
    MA Qiang, YANG Xiao
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    Based on the systematical collection of historical data, and quantitative statistics and analysis, this paper examines the characteristics and rules of floods and droughts of Jialing River in the Ming and Qing dynasties. Five main conclusions can be drawn as follows. (1) The disasters occurred frequently, with floods a bit more than droughts. The frequency of the former is 3.03 times per year while the latter is 2.56 times. (2) Most of the disasters occurred in May, June and July in the Chinese lunar calendar. Specifically, over half of the flood events occurred in these months, accounting for 69.5% of the total, and more than half of the drought events were observed in this period. (3) The Fujiang River basin suffered far more disasters than other areas. It witnessed 31% of flood events and 38% of drought events of Jialing River basin. (4) There are more normal and major disasters than extremely serious disasters. Extremely serious floods accounted for 10.85% of all the floods in this basin during this period, and extremely serious droughts accounted for 12.29% of the total. (5) The forest coverage is inversely proportional to the frequency of floods and droughts in this area. We believe that the results will provide reference for disaster mitigation and prevention in this basin.
  • Article
    YIN Jie, DAI Erfu, WU Shaohong, PAN Tao
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    Typhoon disasters cause great losses in coastal regions of China, and typhoon disaster risk assessment can provide scientific basis for disaster loss prevention. It is a basic work to assess its risk quantitatively in discussion on the relationship between typhoon intensity grade and disaster loss. In this paper, 174 typhoon paths data and disaster situation data from 1954 to 2008, and intensity grade information for each typhoon event from track dataset are used to analyze the relationship between typhoon intensity grade and 8 loss indices. The typhoon intensity grade is characterized by average wind speed. The loss indices include crop afflicted area, crop failure area, afflicted population, mortality, injuried, settlement population, collapsed buildings, and direct economic loss, which belong to four kinds of hazard resilient society (crops, population, house and economy). Based on typhoon wind theory, the affected range of each typhoon is extracted by doing buffer in spatial analysis module on ArcGIS9.3. According to the ranges, the 8 indices for loss rates could be calculated. The relationship between typhoon intensity grade and disaster loss rates are fitted by statistical method, and the loss rate curves are obtained subsequently. The loss rate curves are showed in exponential forms. Based on the typhoon intensity grade division standard and loss rate curves, the scheme of typhoon disaster loss criteria is established, which could be divided into four grades: slight, light, medium and severe. In the criteria, each grade could be characterized by 8 loss indices. The results indicate that loss rates are exponentially increasing with typhoon intensity grade, namely, the higher the intensity grade, the larger the amount of losses. When the intensity grade is 4, the loss rates are increasing sharply. Crops are the most affected in four kinds of hazard resilient society when typhoons landing, and in the severe case, 63.25% of crops area suffers from typhoon disaster. However, mortality rate, injury rate, collapsed buildings rate and direct economic loss rate are relatively low, which indicate that China has the capacity of calamity reduction to avoid large losses. The typhoon disaster loss rate criteria established in this paper could be suitable in China and useful in quantitative vulnerability and risk assessment in further studies.
  • Article
    WANG Jiping, HUANG Zhilin, LIU Yang, XU Shenlai, WEI Wei, CHEN Liding
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    The patterns of topography and landform, defined as basic landscape elements in watershed, have important inpacts on soil erosion processes. In this paper, the watersheds based on 42 hydrological stations, located within the region from Hekouzhen to Longmen (Helong section) in the middle reaches of the Yellow River, were selected as the study area, and the relationship between watershed topography and erosion-sediment processes was analyzed by the correlation and path analysis based on acquisition of topographic features and estimation of soil erosion and sediment yield. The results showed that the number and length of streams and its total number at a given level were the main factors affecting the intensity of soil erosion, and the stream-length ratio, the ratio of bifurcation and stream order have a close relationship with the soil erosion modulus at the river channel level. However, at watershed level, slope roughness (Sp), watershed relative height difference (Rp), roundness ratio (Rc) and watershed valley length ratio (Rh) are the main topographical landscape indices that affect the spatial variation of soil and water loss, among them, slope roughness is the most fundamental and most important explanatory variable of all topographical landscape indices. The complex interaction among the indicators directly or indirectly affects the process of soil erosion and sediment yield. The path analysis model constructed with topographical factors could explain 65% of the variation for soil erosion modulus (EM), 33% of the variation for sediment transport modulus (SM), and 20% of the variation for sediment delivery ratio. These analysis and computation results are helpful to get a better understanding of the importance of topographic patterns and to build more accurate soil erosion process models.
  • Article
    XUE Ling, WENG Jin
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    Since the 1990s, cities in China have experienced a period of rapid growth in economy. In face of the increasing complexity of the urban sprawl, many big cities are planning to build new towns to avoid over-intensive population and infrastructure construction and to ease the pressure on urban centers. Some findings show that the rapid increase of the share of service industries in the local economy can raise the probability of the emergence of subcenters. This paper builds a mathematic model of spatial structure of metropolitan commerce based on the theory of New Economic Geography in old and new center scenarios. By using agent-based modeling and out-of-equilibrium simulation, the spatial structure of subcenters can be observed dynamically in different scenarios. Dynamic simulations show that: (1) Population growth in metropolitan area is conducive to subcenters which implies the commercial centers emerged in the suburban areas were mostly subjected to population pilot policy. (2) The continuous growth of demand scale and capacity depend on the formation of the polycentric structure in metropolitan areas. The capacity of consumptions has great impact on agglomeration of subcenters. (3) The greater the gap of commercial fixed input between the new and old centers is, the more imbalanced urban space distribution would be presented. It is more likely to form the core-periphery structure. If the fixed cost is reduced continuously in suburban areas, it is beneficial for the formation of subcenters and the core-periphery structure of metropolitan areas could be changed gradually. (4) Transportation is a double-edged sword. Commerce and business tend to gather in the place with location advantages, and continuous improvements in traffic condition between old and new centers in metropolitan areas will accelerate the spatial concentration in the old center. The probability of the emergence of subcenters decreases with the increase of the distance to the city center, which implies the subcenters emerged in the metropolitan areas were mostly close to the central area of the city and the decentralization of population in the metropolitan areas was still limited in spatial scale. (5) Due to love-of-varieties, the specialization and diversity make great contribution to the formation of subcenters in metropolitan areas by continuous innovation and difference-making competition strategy.
  • Article
    LU Shasha, GUAN Xingliang, WANG Zhenbo, SONG Ci
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    Spatial field is an effective tool which can be used to describe the regional development pattern and spatial differences for the decision makers. With the application of principal components analysis, raster cost weighted distance method and k-order data fields, this paper attempts to comprehensively measure the nodality index for central cities, regional accessibility, as well as the spatial field in the Yangtze River Delta Economic Zone, and to reveal the spatial distribution and evolution of regional development. The results indicate that central cities in the Yangtze River Delta Economic Zone have made great progress during the past 10 years and this region tends to be evenly developed. Moreover, regional accessibility condition continues to be improved and the average accessible distance for 3 hours increased by 41 km (from 81 km in 2000 to 122 km in 2008). Most of the central cities in Yangtze River Delta Economic Zone have been covered in the "3-hour metropolitan area" of Shanghai except for Zhoushan and Taizhou. In addition, regional spatial field increased significantly from 2000 to 2008. The spatial heterogeneities are conspicuous and the overall situation reveals that the spatial field in the north is better than that in the south. The distribution pattern of spatial field appears to be single-core with a "Z"-shaped pattern in 2000, while that in 2008 tends to be a "multi-polar" network form. According to the natural breaks method, the distribution pattern of spatial field in Yangtze River Delta Economic Zone can be appropriately divided into five major types, i.e., higher field energy region, high field energy region, the transitional region, lower field energy region and low field energy region. Furthermore, the high field energy region is mainly located in the metropolitan areas of Shanghai, Nanjing, Hangzhou, Suzhou-Wuxi-Changzhou, and the development axis areas of Shanghai-Nanjing and Shanghai-Hangzhou. Most parts of the core and potential regions are located along the north wing of Yangtze River Delta Economic Zone.
  • Article
    WU Qing, CHENG Jinping, ZHONG Shiyu, LI Yu
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    An urban human settlement environment index system which includes 5 comprehensive indexes (living relevance, living convenience, residential security, environmental comfort and the health of environment), and 32 components were set up based on the requirements of different subjects. Taking Xintang Town of Guangzhou City as an example, this paper revealed the requirement characteristics of human settlement environment elements of different subjects with questionnaire surveys and non-parameter test analysis, and discussed the impact factors and space distribution of settlement environment elements of different groups with correlation analysis and cluster analysis. The research demonstrates that: interviewees had differences in the demand for 10 elements, while 22 elements in common. In the 22 elements in common, interviewees’ demand for 7 elements, for example, neighborhoods have been basically met, while the demands for the other 15 elements such as traffic safety have not been satisfied. In the social and economic attributes, the residential time influences most of the 10 elements in difference (the 9th), while the gender influences least (the 3rd). There is a maximum of correlation between leisure-time activities, commercial outlets, acoustic environment and age, and a maximum of correlation between housing types, recreational facilities, atmosphere environment, environmental pollution control, green space in urban and rural areas, the effect of environmental publicity and residential time. In 4 groups, highly-educated groups mostly focus on leisure-time activities and atmosphere, while high-income groups show great concern on environmental pollution control, green space in urban and rural areas, and the effect of environmental publicity. Low-income groups mostly focus on housing types, recreational facilities, ways to travel and acoustic environment, while low-educated groups are mostly concerned about commercial outlets.
  • Article
    YE Qiang, TAN Yitian, ZHAO Xuebin, LUO Liwu, CHEN Na, XIANG Hui
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    Commercial network planning is an important legal basis to guide and administer urban development of commercial space. Assessment of implementation effect is one of the concrete measures of examining the planning. Most of urban planning assessments in China adopted qualitative methods, which cannot guarantee the objectivity and accuracy of the evaluation to some degree. This paper conducts a comparative study on current development situation and commercial network planning by applying GIS methods from two aspects of the spatial layout and format structure, based on the commercial network planning and survey data of Changsha city. The results are shown as follows. There are large differences between planning and current situation of commercial network. Commercial network planning has not focused on the structure of urban space, the development stage of commercial activities and spatial location selection mechanism, thus failed to effectively promote the commercial spatial structure evolution and development.
  • Article
    LU Junyu, HUANG Xianjin, CHEN Yi, XIAO Xiao
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    Carbon footprint, as an important index to measure CO2 and other greenhouse gases into the equivalence of CO2 directly or indirectly emitted in the life cycle of production, can reflect the level of stress on the ecological environment of a human activity or a product. This article built a carbon footprint model to measure carbon footprint, ecological capacity of carbon and carbon deficit in different regions by using energy consumption and regional land use data from 1997 to 2008. Then the study, based on the conception of gravity derived from physics, estimated the provincial carbon footprint center of gravity from 1997 to 2008, analyzed the spatial and temporal variations and summarized the reasons for the center changes so as to understand the regional differences of carbon emissions of energy consumption. In addition, based on the index from 1997 to 2008 calculated through carbon footprint pressure index model, we divided China into five categories, namely the high degree of ecological carrying areas, the general degree of ecological carrying areas, the general transitional areas, the general degree of ecological pressure areas and the high degree of ecological pressure areas. At the same time, according to the change intensity of the carbon footprint pressure index between two time points of different areas, this article divided China into five levels, namely the ecological pressure relief areas, the ecological pressure slight increase areas, the ecological pressure moderate increase areas, the ecological pressure severe increase areas and the ecological pressure extreme increase areas.
  • Article
    WAN Xucai, WANG Houting, FU Chaoxia, MA Hongzhuan
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    This paper, taking the major tourism cities as an example, attempts to analyze the intercity difference of inbound tourism development in China, and examines the influencing factors in order to provide a theoretical basis for the practice of inbound tourism development in the cities. The article, selecting the person-day number of inbound tourists as the index to measure the level of inbound tourism development, explores the present difference situation of inbound tourism development by the method of mean ratio and the impact of tourism product, celebrity rating, location condition and external economy on inbound tourism development by the method of multiple linear regression. The results show that: (1) The intercity difference of inbound tourism development in China is very big, regional concentration is very prominent, and the cities with developed inbound tourism are mostly located in eastern China; (2) The external economy has the greatest impact on inbound tourism development in the cities, followed by the celebrity rating, while the tourism product and location distance are less important.
  • Article
    YANG Zhao, SHANGGUAN Xiaoyan, CAI Yongshou, ZHANG Jie, HAN Guosheng
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    Tourism migration is a focus issue in international tourism geography research. Tourism labor migrants, widely distributed in earlier developed and more attractive sightseeing places in China, can be taken as an entry point of domestic tourism migration study. Taking Jiuzhaigou as a case study, the article analyzes motivation structure, strength and process of the tourism labor migrants in Jiuzhaigou through a mixed approach. The findings of the study are as follows. First, data source from questionnaire and in-depth interviewing jointly show that employment gains, employment positive attributes, place attractiveness, social capital, and lifestyle are five-dimensional structure of the beginning motivation of tourism labor migration in Jiuzhaigou. Employment gains are the strongest motivational forces, and then comes place attractiveness. Secondly, in-depth interviewing data show that employment gains, employment positive attributes, place attractiveness and social capital are four-dimensional structure of the subsequent motivation in which place attractiveness takes the priority, followed by employment positive attributes. Thirdly, a dynamic motivational change is found in different stages of tourism labor migration. Questionnaire findings can measure motivation structure, strength and its correlative demographic characteristic groups. In-depth interviewing may inquiry into the subsequent motivation structure and strength, and form data and methods triangulation with questionnaire. The combination of the two techniques can increase study validity, and proves appropriate for motivation research of tourism labor migration.
  • Article
    YIN Shoubing, LIU Yunxia, ZHAO Peng
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    Qualitative research methodology is used in this study, such as participant observation and in-depth interview. Based on reviewing the progress of tourism development in Xidi village, it has been found that entrepreneurship and tourism demands are the critical internal and external factors in the development of the small tourism firms (STFs), and both factors have exerted great influence on the governance model. Three stages of governance model have been identified by the intervention degree of government, community and the third sector (e.g., Heritage Protection Organizations). The three stages are the community governance model with spontaneous community participation, the network governance model featuring the joint controls by government, community and the third sector, and the hierarchy governance model with government's constantly strengthening commands and controls. Along with the changes in governance model, government's commands and controls have been strengthened continuously, while government's interest demands led to structural changes in the tourism markets, which caused the changes in the operating characteristics and spatial structure of the STFs. Meanwhile, the entrepreneurship and imitative innovation capacity of the residents have been influenced, hence the development pace and scale of the STFs presented different features in different stages. As indicated by the research findings, the optimization of governance model is the key point to the sustainable development of the STFs.
  • Article
    CHEN Yaohua, YANG Liu, YAN Siqi
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    Taking the world cultural heritage—Kaiping Diaolou as an example, this paper investigates a special type of world heritage—"scattered-type villages", from the perspectives of their concept, and examines five characteristics of those villages: scatter in the space layout, integrity in the village pattern, harmony in the overall theme, distinction in the partition style, and outstanding universal value as a unique type of world heritage. In addition, this paper probes into the effects that those characteristics exert on heritage sites, such as the negative effects on their overall management and utilization. On the basis of the study of the protection and development status quo of Kaiping Diaolou and Villages, with comparison and reference to the experiences from other similar "scattered-type villages", and in view of the independence, differentiation and indivisibility of heritage sites, this paper proposes some strategies of protection and development, such as overall protection, overall management plan, region interaction, unified image, outlining the characteristics and the link connection, etc., so that the heritage sites could be well protected in terms of their authenticity and integrity, and sustainably develop as well. Against the background of rapid urbanization and new countryside construction in China, this paper is inspirational to the problem of how to strictly protect valuable world heritages as well as to efficiently develop local economy.
  • Article
    WANG Bo, ZHEN Feng, XI Guangliang, QIAN Qian, WU Chengyue, ZHANG Hao
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    Along with a new development trend of mobile information technology, nowadays people can even communicate with others at anytime and anywhere with any devices. Micro-blog, as one of the most important social network platforms, has experienced vigorous growth and now becomes one of the most popular Internet applications in China. Although micro-blog has become a hotspot of research in areas such as computer and sociology, there have been relatively few studies from the perspective of geography. Compared with the existing researches on cybergeography mainly focused on network infrastructure used to simulate the influence of information, the research based on micro-blog users' relationship will undoubtedly reflect interpersonal communication more directly, thus help to analyze the impact of information on interpersonal social network. Therefore, this paper tries to analyze cybergeography based on micro-blog users' relationship. The study firstly selects 100 micro-blog users in Nanjing and collects these users' followers, followings, friends, and their geospatial information. Then it analyzes the geographical features, forms and the reasons. The results are obtained as follows. (1) The role of distance still acts in the network information space, for a certain distance attenuation phenomenon still exists in network information contact. And the amount of network information contact with these selected users in Jiangsu province occupies the largest part of the country's total, while this figure in Nanjing city also occupies most parts of the total in Jiangsu Province. (2) The network information contact is well consistent with the actual social-economic contact, for not only the strength of network information shows a relative consistence with the social-economic development, but also the pattern of network information contact shows a relative consistence with the overall pattern of social-economic development. (3) The network information space also shows an obvious hierarchy, for not only the strength of network information contact shows different hierarchical levels, but also the network information contact between cities is imbalanced and characterized by asymmetry. Lastly, the study argues that the role of distance and the actual socio-economic contact have joint impacts on the network information space, which has a certain similarity with the function mechanism on the actual geographic space.