The spatial distribution of urban population can reflect significantly urban functions and development status. Shenyang, as a typical old industrial city in China, has experienced considerable changes in spatial distr...The spatial distribution of urban population can reflect significantly urban functions and development status. Shenyang, as a typical old industrial city in China, has experienced considerable changes in spatial distribution of population in the process of urban transformation, resulting in the change of urban spatial structure. Based on the sub-district data of Chinese national population censuses in 1982, 1990 and 2000, this study simulates the evolution pattern of spatial distribution of urban population in Shenyang City. Using statistical method and exploratory spatial data analysis (ESDA), we found that the population distribution, on the whole, has presented a balanced and decentralized trend since the 1980s, which characterizes with Chinese suburbanization. Furthermore, based on the investigation of the pattern of population distribution, it is concluded that the negative exponential model fitted the distribution best, and population concentration in the inner suburb kept increasing gradually, meanwhile, the spatial structure of population distribution has presented a polycentric feature since the 1980s. The parameters of the model show that population in the urban core concentrate significantly all the time. The increase of population in the inner suburb influences the population distribution pattern more and more importantly, but the concentration intensity of population cores in inner suburb is still low.展开更多
The spatialization of population of counties in China is significant. Firstly, we can gain the estimated values of population density adaptive to different kinds of regions. Secondly, we can integrate effectively popu...The spatialization of population of counties in China is significant. Firstly, we can gain the estimated values of population density adaptive to different kinds of regions. Secondly, we can integrate effectively population data with other data including natural resources, environment, society and economy, build 1km GRIDs of natural resources reserves per person, population density and other economic and environmental data, which are necessary to the national management and macro adjustment and control of natural resources and dynamic monitoring of population. In order to establish population information system serving national decision making, three steps ought to be followed:1) establishing complete geographical spatial data foundation infrastructure including the establishment of electric map of residence with high resolution using topographical map with large scale and high resolution satellite remote sensing data, the determination of attribute information of housing and office buildings, and creating complete set of attribute database and rapid data updating; 2) establishing complete census systems including improving the transformation efficiency from census data to digital database and strengthening the link of census database and geographical spatial database, meanwhile, the government should attach great importance to the establishment and integration of population migration database; 3) considering there is no GIS software specially serving the analysis and management of population data, a practical approach is to add special modules to present software system, which works as a bridge actualizing the digitization and spatialization of population geography research.展开更多
During the last 30 years, China has witnessed rapid economic growth and dramatic urbanization, with about 1.2 x 107 rural people migrating annually into urban areas. Meanwhile, especially since 1995, the rural populat...During the last 30 years, China has witnessed rapid economic growth and dramatic urbanization, with about 1.2 x 107 rural people migrating annually into urban areas. Meanwhile, especially since 1995, the rural population has been declining, which is closely linked to land circulation and the increase in farm size in many villages. Increasing scale of farming operations is often regarded as a key to avoiding the abandonment of farmland and to increasing the income of rural farmers. However, until now, there has been little research on the spatial and temporal variability of farm size at the national level in China. Using data from the national agricultural cen- sus and rural household surveys, this study examines the characteristics of land use circulation and the consequent changes in the area of farmland per household. The results show that: 1) 12.2% of rural households were involved in land circulation at the national level. The highest amounts of land circulation have occurred in those provinces where the farmland per capita is more than 0.2 ha or less than 0.1 ha; 2) over 80% of households operate less than 0.6 ha of farmland; 3) the proportion of mid-sized farms (between 0.2 ha and 0.6 ha per household) has decreased while the smallest and the largest farms have increased. This bears some similarity with the phenomenon known as the 'disappearing middle', referring to the changes in farm size. This study establishes a framework for interpreting the factors affecting the changes in farm size in China, which include two promoting factors (urbanization and agriculture) and four hindering fac- tors (agricultual land system, household registration, stable clan system, and farmland loss).展开更多
Recently, Japan has experienced a low birthrate and an aging population. The development of communication robots, such as cleaning and a care-giver robot, has been progressing. Care-giver robots provide daily assistan...Recently, Japan has experienced a low birthrate and an aging population. The development of communication robots, such as cleaning and a care-giver robot, has been progressing. Care-giver robots provide daily assistance, including contacting emergency services. This study is part of the "study on planning techniques of living space in harmony with robots", and focused on the elderly. Minimum distance was the subjects felt "I do not want any more approached". Subjects were 21 elderly persons (eight males and thirteen females), aged 66-86 years. The experimental room was an assembly room in a public accommodation (14 m× 6.5 m). The small mobile robot used in this experiment was external form dimensions of 120 mm (W)× 130 mm (D)× 70 mm (H), In this experiment, considering the personal space as the small mobile robot is watching robot without support function for person. The robot moved toward standing or sitting subjects at constant velocities from a distance 5 m apart. Research factors are 5 angles (0°, 45°, 90°, 135° and 180°) and 2 speeds (0.08 m/s and 0.24 m/s).展开更多
With the further development of socialist market economy, the mobility of factor markets in China, especially the labor market, is strengthened. Externalities interacts with the agglomeration of productive factors. Un...With the further development of socialist market economy, the mobility of factor markets in China, especially the labor market, is strengthened. Externalities interacts with the agglomeration of productive factors. Under the framework of new economic geography, this article presents a theoretical model involving the endogenous population density affected by urban externalities. Results show that the population density is more concentrated around the center because the degree and extent of interaction between individuals intensifies when the distance from the center decreases. When there are several externalities resources, the aggregation of externalities changes the configuration of spatial factor allocation. These results fit well with the empirical facts about the decreasing density of floating population along the cities of Guangzhou, Dongguan and Shenzhen in Guangdong Province which is situated in the eastern coast of the Pearl River Delta. We fred that under the impacts of externalities released from Hong Kong into the coast, floating population was more concentrated around Shenzhen and Dongguan, which are more adjacent to Hong Kong compared with Guangzhou City.展开更多
Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. ...Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths (3700-4200 m) at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions (e.g., nutrient and thermal deficits, plant interactions) across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran's eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming.展开更多
With population growth and increasing pressure on land resources,land carrying capacity(LCC) and food safety have been attracting great attention worldwide.From the point of man-grain relationship and by establishing ...With population growth and increasing pressure on land resources,land carrying capacity(LCC) and food safety have been attracting great attention worldwide.From the point of man-grain relationship and by establishing LCC and land carrying capacity index(LCCI) models,this article firstly analyzes the spatial-temporal dynamics of LCC of China from 1949 to 2005 at county,provincial and national levels.Choosing 2005 as a representative year,this article then evaluates the LCC of 264 pastoral regions(semipastoral regions),663 urban regions and 592 poverty stricken regions of the country.The results show that:(1) from 1949 to 2005,with the increase of grain production,the LCC of China has been improved conspicuously,but due to the rapid population growth,the production can only maintain a low level grain consumption;(2) over the past 25 years(1980-2005),the number of population overloading provinces decreased from 23 to 15 and the mangrain relationship has been improved gradually,but there were more overloading provinces than surplus provinces in China;(3) at county level,there were 1572 overloading counties in 1980 accounting for 68.26% of the total counties of the country and where were 649 million people lived,while in 1990,2000 and 2005,the number of overloading counties were 1066,1133 and 1087 respectively,which shows that the man-grain relationship has been improved obviously during the past 25 years;as for spatial distribution,the surplus counties were mainly concentrated in agriculture developed regions,such as Northeast Plain,North China Plain,middle and lower Reaches of the Yangtze River Plain,and overloading counties were mainly located in regions with poor natural environment and low grain production capacity,such as Northwest China,Tibetan Plateau and Loess Plateau and economically developed urban regions,such as Beijing,Tianjin and Shanghai;(4) animal husbandry improved greatly the LCC of pastoral and semi-pastoral regions,while urban regions were overloading for increasing population pressure and more than half of poverty stricken regions were overloading due to critical natural environment and poor economic conditions.展开更多
We investigate the evolutionary prisoner's dilemma game in structured populations by introducing dimers, which are defined as that two players in each dimer always hold a same strategy. We find that influences of dim...We investigate the evolutionary prisoner's dilemma game in structured populations by introducing dimers, which are defined as that two players in each dimer always hold a same strategy. We find that influences of dimets on cooperation depend on the type of dimers and the population structure. For those dimers in which players interact with each other, the cooperation level increases with the number of dimers though the cooperation improvement level depends on the type of network structures. On the other hand, the dimers, in which there are not mutual interactions, will not do any good to the cooperation level in a single community, but interestingly, will improve the cooperation level in a population with two communities. We explore the relationship between dimers and self-interactions and find that the effects of dimers are similar to that of self-interactions. Also, we find that the dimers, which are established over two communities in a multi-community network, act as one type of interaction through which information between communities is communicated by the requirement that two players in a dimer hold a same strategy.展开更多
Based on comprehensive analysis of the impact of population aging to social and economic development,a comprehensive evaluation system including 18 indexes was constructed for evaluating regional pressure of populatio...Based on comprehensive analysis of the impact of population aging to social and economic development,a comprehensive evaluation system including 18 indexes was constructed for evaluating regional pressure of population aging on social and economic development.Using statistics data of 31 regions in China from 2004 to 2008,the pressure of population aging on social and economic development,was comprehensively evaluated by using the factor analysis method.The spatial distribution of population aging in China was also analyzed.This study is to provide scientific basis for government to make strategies of coping with population aging according to regional pressure of population aging on social and economic development in China.展开更多
In this paper, an approach to simulate the spatial dis- tribution of urban population is proposed using urban land use and population statistical data through the geographical information systems (GIS). Then, the spat...In this paper, an approach to simulate the spatial dis- tribution of urban population is proposed using urban land use and population statistical data through the geographical information systems (GIS). Then, the spatial population distribution of Urumqi as a case is simulated by the approach mentioned above and its varying patterns are analyzed by the raster population surface. As a result, producing raster population surface is more accurate and natural than the traditional choropleth map of population density. Concerning the spatial population distribution of Urumqi, the population density declines from south to north and the population distribution mainly presents "T-type", the population distribution presents multi-centre agglomeration and the population distribu- tion of the districts shows different features. The population den- sity varies significantly with the increase in the distance from central business district (CBD). Finally, it is found in this paper that the development history of districts, terrain and traffic road are main factors that have an influence Urumqi’s population dis- tribution. This paper tries to provide more accurate population data for the plan and management of urban land, traffic and public facilities in order to enrich the researches on urban population distribution.展开更多
The "Hu Line" has been regarded as one of the greatest geographical discoveries in China because it reveals the significant spatial relationship between human activity and natural environment. The spatial ev...The "Hu Line" has been regarded as one of the greatest geographical discoveries in China because it reveals the significant spatial relationship between human activity and natural environment. The spatial evolution of population on both sides of the "Hu Line" has had important implications for both urbanization and regional development and has attracted widespread attention during the dramatic economic and social changes since the implementation of reform and opening-up policy in China in 1978. Using Geographical Information System(GIS) techniques, this paper studied the stability of the "Hu Line" and the spatial patterns of population growth on each side by constructing a spatial database of China's census data from 1982 to 2010. The findings are as follows:(1) In the last 30 years, the "Hu Line" has remained relatively stable, but a new tendency of population change has begun to emerge. The population ratio either side, namely, the southeast half(SEH) and the northwest half(NWH), of the "Hu Line" remains at roughly 94:6(SHE : NWH). Noteworthy, the proportion of population in the SEH of the "Hu Line" has been decreasing slightly, while that in the NWH has been increasing slightly, as the latter has benefited from its higher rate of natural population growth.(2) The spatial patterns of population growth on both sides of the "Hu Line" were quite different. The degree of population concentration in the SEH increased faster than the NWH. Regions with a negative population growth rate have rapidly expanded; these were mainly located in the south of the "Qinling Mountains-Huaihe River belt" and northeastern China. Meanwhile, regions with a fast population growth rate were mainly concentrated in the Yangtze River Delta, the Pearl River Delta, and the Beijing-Tianjin metropolitan area. Thus, the spatial pattern of population growth in the SEH presented a concentration pattern that could be called "Matthew effect pattern".(3) The spatial pattern of population growth in the NWH could be regarded as the "Relative Balance pattern." In the NWH, the population growth rate was positive and the degree of population concentration was very low. There were many minority populations located in the NWH that usually lived in a dispersed pattern but had a higher rate of natural population growth due to the preferential population policy. There were also some regions with a negative rate of population growth in the NWH, which were mainly located close to the "Hu Line" and the Ancient Silk Road.(4) In the future, the spatial patterns of population growth on both sides of the "Hu Line" may continue to evolve. For the SEH, the capacity to attract more people to small and medium-sized cities and towns should be enhanced. For the NWH, the emphasis should be placed on promoting urbanization and enhancing population agglomeration in its major cities.展开更多
This paper uses data for the period 1950-2050 compiled by the United Nations Population Division together with methods including spatial autocorrelation analysis, hie- rarchical cluster analysis and the standard devia...This paper uses data for the period 1950-2050 compiled by the United Nations Population Division together with methods including spatial autocorrelation analysis, hie- rarchical cluster analysis and the standard deviational ellipse, to analyze the spatio-temporal evolution of population and urbanization in the 75 countries located along the routes of the Silk Road Economic Belt and the 21st-century Maritime Silk Road, to identify future popula- tion growth and urbanization hotspots. The results reveal the following: First, in 2015, the majority of Belt and Road countries in Europe, South Asia and Southeast Asia had high population densities, whereas most countries in Central Asia, North Africa and West Asia, as well as Russia and Mongolia, had low population densities; the majority of countries in South Asia, Southeast Asia, Central Asia, West Asia and North Africa had rapid population growth, whereas many countries in Europe had negative population growth; and five Belt and Road countries are in the initial stage of urbanization, 44 countries are in the acceleration stage of urbanization, and 26 are in the terminal stage of urbanization. Second, in the century from 1950 to 2050, the mean center of the study area's population is consistently located in the border region between India and China. Prior to 2000, the trajectory of the mean center was from northwest to southeast, but from 2000 it is on a southward trajectory, as the population of the study area becomes more concentrated. Future population growth hotspots are predicted to be in South Asia, West Asia and Southeast Asia, and hotspot countries for the period 2015-2030 include India, China, Pakistan and Indonesia, though China will move into nega- tive population growth after 2030. Third, the overall urban population of Belt and Road coun- tries increased from 22% in 1950 to 49% in 2015, and it is expected to gradually catch up with the world average, reaching 64% in 2050. The different levels of urbanization in different countries display significant spatial dependency, and in the hundred-year period under con-sideration, this dependency increases before eventually weakening. Fourth, between 2015 and 2030, urban population hotspots will include Thailand, China, Laos and Albania, while Kuwait, Cyprus, Qatar and Estonia will be urban "coldspots." Fifth, there were 293 cities with populations over 1 million located along the Belt and Road in 2015, but that number Js ex- pected to increase to 377 by 2030. Of those, 43 will be in China, with many of the others located in India, Indonesia and the eastern Mediterranean.展开更多
Based on the prefecture-level data of the 2000 and 2010 national censuses, the spatial evolution of China's semi-urbanization is analyzed in this study. The stages of urbanization are re-examined by considering se...Based on the prefecture-level data of the 2000 and 2010 national censuses, the spatial evolution of China's semi-urbanization is analyzed in this study. The stages of urbanization are re-examined by considering semi-urbanization. Nine types of urban development are presented according to the relations between semi-urbanization and urbanization, and China's urbanization is divided into five stages, namely, high incoordination, incoordination, low coordination, coordination, and high coordination. Results show that China's semi-urbanization rate varies significantly from one area to another; its order in 2010 from the highest to the lowest value was as follows: east, middle, west, and northeast. Urbanization and semi-urbanization rates in inland cities increase much faster than those in coastal cities. In addition, semi-urbanization displays a spatial pattern similar to that of urbanization across China, with the sole exception of the northeastern region. Through a spatial autocorrelation analysis, the spatial concentration of semi-urbanization is determined to be increasing. High-value concentration areas are expanding in the coastal east, whereas low-value concentration areas are growing in the northeast. Lastly, the evolution of China's urbanization model suggests a weakening trend of coordination between urbanization and semi-urbanization over the studied decade. Semi-urbanization can be viewed as a special production of China's hukou system, which restricts the permanent settlement of migrants in cities. As such, China's semi-urbanization trend is expected to exhibit a reversed U-shaped pattern as urbanization and citizenization develop.展开更多
基金Under the auspices of Knowledge Innovation Programs of Chinese Academy of Sciences (No. KZCX2-YW-342, KZCX2-YW-321-04)National Natural Science Foundation of China (No. 40635030)
文摘The spatial distribution of urban population can reflect significantly urban functions and development status. Shenyang, as a typical old industrial city in China, has experienced considerable changes in spatial distribution of population in the process of urban transformation, resulting in the change of urban spatial structure. Based on the sub-district data of Chinese national population censuses in 1982, 1990 and 2000, this study simulates the evolution pattern of spatial distribution of urban population in Shenyang City. Using statistical method and exploratory spatial data analysis (ESDA), we found that the population distribution, on the whole, has presented a balanced and decentralized trend since the 1980s, which characterizes with Chinese suburbanization. Furthermore, based on the investigation of the pattern of population distribution, it is concluded that the negative exponential model fitted the distribution best, and population concentration in the inner suburb kept increasing gradually, meanwhile, the spatial structure of population distribution has presented a polycentric feature since the 1980s. The parameters of the model show that population in the urban core concentrate significantly all the time. The increase of population in the inner suburb influences the population distribution pattern more and more importantly, but the concentration intensity of population cores in inner suburb is still low.
文摘The spatialization of population of counties in China is significant. Firstly, we can gain the estimated values of population density adaptive to different kinds of regions. Secondly, we can integrate effectively population data with other data including natural resources, environment, society and economy, build 1km GRIDs of natural resources reserves per person, population density and other economic and environmental data, which are necessary to the national management and macro adjustment and control of natural resources and dynamic monitoring of population. In order to establish population information system serving national decision making, three steps ought to be followed:1) establishing complete geographical spatial data foundation infrastructure including the establishment of electric map of residence with high resolution using topographical map with large scale and high resolution satellite remote sensing data, the determination of attribute information of housing and office buildings, and creating complete set of attribute database and rapid data updating; 2) establishing complete census systems including improving the transformation efficiency from census data to digital database and strengthening the link of census database and geographical spatial database, meanwhile, the government should attach great importance to the establishment and integration of population migration database; 3) considering there is no GIS software specially serving the analysis and management of population data, a practical approach is to add special modules to present software system, which works as a bridge actualizing the digitization and spatialization of population geography research.
基金Under the auspices of National Natural Science Foundation of China(No.4097111241161140352)Ministry of Environmental Protection of the People's Republic of China(No.STSN-09-04)
文摘During the last 30 years, China has witnessed rapid economic growth and dramatic urbanization, with about 1.2 x 107 rural people migrating annually into urban areas. Meanwhile, especially since 1995, the rural population has been declining, which is closely linked to land circulation and the increase in farm size in many villages. Increasing scale of farming operations is often regarded as a key to avoiding the abandonment of farmland and to increasing the income of rural farmers. However, until now, there has been little research on the spatial and temporal variability of farm size at the national level in China. Using data from the national agricultural cen- sus and rural household surveys, this study examines the characteristics of land use circulation and the consequent changes in the area of farmland per household. The results show that: 1) 12.2% of rural households were involved in land circulation at the national level. The highest amounts of land circulation have occurred in those provinces where the farmland per capita is more than 0.2 ha or less than 0.1 ha; 2) over 80% of households operate less than 0.6 ha of farmland; 3) the proportion of mid-sized farms (between 0.2 ha and 0.6 ha per household) has decreased while the smallest and the largest farms have increased. This bears some similarity with the phenomenon known as the 'disappearing middle', referring to the changes in farm size. This study establishes a framework for interpreting the factors affecting the changes in farm size in China, which include two promoting factors (urbanization and agriculture) and four hindering fac- tors (agricultual land system, household registration, stable clan system, and farmland loss).
文摘Recently, Japan has experienced a low birthrate and an aging population. The development of communication robots, such as cleaning and a care-giver robot, has been progressing. Care-giver robots provide daily assistance, including contacting emergency services. This study is part of the "study on planning techniques of living space in harmony with robots", and focused on the elderly. Minimum distance was the subjects felt "I do not want any more approached". Subjects were 21 elderly persons (eight males and thirteen females), aged 66-86 years. The experimental room was an assembly room in a public accommodation (14 m× 6.5 m). The small mobile robot used in this experiment was external form dimensions of 120 mm (W)× 130 mm (D)× 70 mm (H), In this experiment, considering the personal space as the small mobile robot is watching robot without support function for person. The robot moved toward standing or sitting subjects at constant velocities from a distance 5 m apart. Research factors are 5 angles (0°, 45°, 90°, 135° and 180°) and 2 speeds (0.08 m/s and 0.24 m/s).
基金This paper was supported by National Natural Science Foundation of China (Grant No. 40341008)
文摘With the further development of socialist market economy, the mobility of factor markets in China, especially the labor market, is strengthened. Externalities interacts with the agglomeration of productive factors. Under the framework of new economic geography, this article presents a theoretical model involving the endogenous population density affected by urban externalities. Results show that the population density is more concentrated around the center because the degree and extent of interaction between individuals intensifies when the distance from the center decreases. When there are several externalities resources, the aggregation of externalities changes the configuration of spatial factor allocation. These results fit well with the empirical facts about the decreasing density of floating population along the cities of Guangzhou, Dongguan and Shenzhen in Guangdong Province which is situated in the eastern coast of the Pearl River Delta. We fred that under the impacts of externalities released from Hong Kong into the coast, floating population was more concentrated around Shenzhen and Dongguan, which are more adjacent to Hong Kong compared with Guangzhou City.
基金funded by Studienstiftung des deutschen VolkesGerman Research Foundation for funding(DFG,SCHI 436/14-1,BO 1333/4-1,SCHO 739/14-1)
文摘Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths (3700-4200 m) at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions (e.g., nutrient and thermal deficits, plant interactions) across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran's eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming.
基金supported by the National Basic Research Program of China (Grant no.40771204 and Grant no. 40801223)National Technology R&D Program (Grant no.2006BAC18B01)
文摘With population growth and increasing pressure on land resources,land carrying capacity(LCC) and food safety have been attracting great attention worldwide.From the point of man-grain relationship and by establishing LCC and land carrying capacity index(LCCI) models,this article firstly analyzes the spatial-temporal dynamics of LCC of China from 1949 to 2005 at county,provincial and national levels.Choosing 2005 as a representative year,this article then evaluates the LCC of 264 pastoral regions(semipastoral regions),663 urban regions and 592 poverty stricken regions of the country.The results show that:(1) from 1949 to 2005,with the increase of grain production,the LCC of China has been improved conspicuously,but due to the rapid population growth,the production can only maintain a low level grain consumption;(2) over the past 25 years(1980-2005),the number of population overloading provinces decreased from 23 to 15 and the mangrain relationship has been improved gradually,but there were more overloading provinces than surplus provinces in China;(3) at county level,there were 1572 overloading counties in 1980 accounting for 68.26% of the total counties of the country and where were 649 million people lived,while in 1990,2000 and 2005,the number of overloading counties were 1066,1133 and 1087 respectively,which shows that the man-grain relationship has been improved obviously during the past 25 years;as for spatial distribution,the surplus counties were mainly concentrated in agriculture developed regions,such as Northeast Plain,North China Plain,middle and lower Reaches of the Yangtze River Plain,and overloading counties were mainly located in regions with poor natural environment and low grain production capacity,such as Northwest China,Tibetan Plateau and Loess Plateau and economically developed urban regions,such as Beijing,Tianjin and Shanghai;(4) animal husbandry improved greatly the LCC of pastoral and semi-pastoral regions,while urban regions were overloading for increasing population pressure and more than half of poverty stricken regions were overloading due to critical natural environment and poor economic conditions.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10775022, 90921015the Fundamental Research Funds for the Central Universities
文摘We investigate the evolutionary prisoner's dilemma game in structured populations by introducing dimers, which are defined as that two players in each dimer always hold a same strategy. We find that influences of dimets on cooperation depend on the type of dimers and the population structure. For those dimers in which players interact with each other, the cooperation level increases with the number of dimers though the cooperation improvement level depends on the type of network structures. On the other hand, the dimers, in which there are not mutual interactions, will not do any good to the cooperation level in a single community, but interestingly, will improve the cooperation level in a population with two communities. We explore the relationship between dimers and self-interactions and find that the effects of dimers are similar to that of self-interactions. Also, we find that the dimers, which are established over two communities in a multi-community network, act as one type of interaction through which information between communities is communicated by the requirement that two players in a dimer hold a same strategy.
基金supported by a grant from the Major Programs of Fundamental Special Work of National Science and Technology (Grand No.2007FY110300),which comes from Ministryof Science and Technology of the People’s Republic of China
文摘Based on comprehensive analysis of the impact of population aging to social and economic development,a comprehensive evaluation system including 18 indexes was constructed for evaluating regional pressure of population aging on social and economic development.Using statistics data of 31 regions in China from 2004 to 2008,the pressure of population aging on social and economic development,was comprehensively evaluated by using the factor analysis method.The spatial distribution of population aging in China was also analyzed.This study is to provide scientific basis for government to make strategies of coping with population aging according to regional pressure of population aging on social and economic development in China.
基金This study is supported by the Knowledge Innovation Project of CAS (Grant No. KZCS-SW-355).
文摘In this paper, an approach to simulate the spatial dis- tribution of urban population is proposed using urban land use and population statistical data through the geographical information systems (GIS). Then, the spatial population distribution of Urumqi as a case is simulated by the approach mentioned above and its varying patterns are analyzed by the raster population surface. As a result, producing raster population surface is more accurate and natural than the traditional choropleth map of population density. Concerning the spatial population distribution of Urumqi, the population density declines from south to north and the population distribution mainly presents "T-type", the population distribution presents multi-centre agglomeration and the population distribu- tion of the districts shows different features. The population den- sity varies significantly with the increase in the distance from central business district (CBD). Finally, it is found in this paper that the development history of districts, terrain and traffic road are main factors that have an influence Urumqi’s population dis- tribution. This paper tries to provide more accurate population data for the plan and management of urban land, traffic and public facilities in order to enrich the researches on urban population distribution.
基金National Natural Science Foundation of China,No.41271174Key Project of National Natural Science Foundation of China,No.71433008
文摘The "Hu Line" has been regarded as one of the greatest geographical discoveries in China because it reveals the significant spatial relationship between human activity and natural environment. The spatial evolution of population on both sides of the "Hu Line" has had important implications for both urbanization and regional development and has attracted widespread attention during the dramatic economic and social changes since the implementation of reform and opening-up policy in China in 1978. Using Geographical Information System(GIS) techniques, this paper studied the stability of the "Hu Line" and the spatial patterns of population growth on each side by constructing a spatial database of China's census data from 1982 to 2010. The findings are as follows:(1) In the last 30 years, the "Hu Line" has remained relatively stable, but a new tendency of population change has begun to emerge. The population ratio either side, namely, the southeast half(SEH) and the northwest half(NWH), of the "Hu Line" remains at roughly 94:6(SHE : NWH). Noteworthy, the proportion of population in the SEH of the "Hu Line" has been decreasing slightly, while that in the NWH has been increasing slightly, as the latter has benefited from its higher rate of natural population growth.(2) The spatial patterns of population growth on both sides of the "Hu Line" were quite different. The degree of population concentration in the SEH increased faster than the NWH. Regions with a negative population growth rate have rapidly expanded; these were mainly located in the south of the "Qinling Mountains-Huaihe River belt" and northeastern China. Meanwhile, regions with a fast population growth rate were mainly concentrated in the Yangtze River Delta, the Pearl River Delta, and the Beijing-Tianjin metropolitan area. Thus, the spatial pattern of population growth in the SEH presented a concentration pattern that could be called "Matthew effect pattern".(3) The spatial pattern of population growth in the NWH could be regarded as the "Relative Balance pattern." In the NWH, the population growth rate was positive and the degree of population concentration was very low. There were many minority populations located in the NWH that usually lived in a dispersed pattern but had a higher rate of natural population growth due to the preferential population policy. There were also some regions with a negative rate of population growth in the NWH, which were mainly located close to the "Hu Line" and the Ancient Silk Road.(4) In the future, the spatial patterns of population growth on both sides of the "Hu Line" may continue to evolve. For the SEH, the capacity to attract more people to small and medium-sized cities and towns should be enhanced. For the NWH, the emphasis should be placed on promoting urbanization and enhancing population agglomeration in its major cities.
基金The Strategic Priority Research Program of the CAS,Pan-Third Pole Environment Study for a Green Silk Road(Pan-TPE),No.XDA20040400Key Deployment Project of the CAS,No.ZDRW-ZS-2016-6-2
文摘This paper uses data for the period 1950-2050 compiled by the United Nations Population Division together with methods including spatial autocorrelation analysis, hie- rarchical cluster analysis and the standard deviational ellipse, to analyze the spatio-temporal evolution of population and urbanization in the 75 countries located along the routes of the Silk Road Economic Belt and the 21st-century Maritime Silk Road, to identify future popula- tion growth and urbanization hotspots. The results reveal the following: First, in 2015, the majority of Belt and Road countries in Europe, South Asia and Southeast Asia had high population densities, whereas most countries in Central Asia, North Africa and West Asia, as well as Russia and Mongolia, had low population densities; the majority of countries in South Asia, Southeast Asia, Central Asia, West Asia and North Africa had rapid population growth, whereas many countries in Europe had negative population growth; and five Belt and Road countries are in the initial stage of urbanization, 44 countries are in the acceleration stage of urbanization, and 26 are in the terminal stage of urbanization. Second, in the century from 1950 to 2050, the mean center of the study area's population is consistently located in the border region between India and China. Prior to 2000, the trajectory of the mean center was from northwest to southeast, but from 2000 it is on a southward trajectory, as the population of the study area becomes more concentrated. Future population growth hotspots are predicted to be in South Asia, West Asia and Southeast Asia, and hotspot countries for the period 2015-2030 include India, China, Pakistan and Indonesia, though China will move into nega- tive population growth after 2030. Third, the overall urban population of Belt and Road coun- tries increased from 22% in 1950 to 49% in 2015, and it is expected to gradually catch up with the world average, reaching 64% in 2050. The different levels of urbanization in different countries display significant spatial dependency, and in the hundred-year period under con-sideration, this dependency increases before eventually weakening. Fourth, between 2015 and 2030, urban population hotspots will include Thailand, China, Laos and Albania, while Kuwait, Cyprus, Qatar and Estonia will be urban "coldspots." Fifth, there were 293 cities with populations over 1 million located along the Belt and Road in 2015, but that number Js ex- pected to increase to 377 by 2030. Of those, 43 will be in China, with many of the others located in India, Indonesia and the eastern Mediterranean.
基金National Natural Science Foundation of China,No.41371166
文摘Based on the prefecture-level data of the 2000 and 2010 national censuses, the spatial evolution of China's semi-urbanization is analyzed in this study. The stages of urbanization are re-examined by considering semi-urbanization. Nine types of urban development are presented according to the relations between semi-urbanization and urbanization, and China's urbanization is divided into five stages, namely, high incoordination, incoordination, low coordination, coordination, and high coordination. Results show that China's semi-urbanization rate varies significantly from one area to another; its order in 2010 from the highest to the lowest value was as follows: east, middle, west, and northeast. Urbanization and semi-urbanization rates in inland cities increase much faster than those in coastal cities. In addition, semi-urbanization displays a spatial pattern similar to that of urbanization across China, with the sole exception of the northeastern region. Through a spatial autocorrelation analysis, the spatial concentration of semi-urbanization is determined to be increasing. High-value concentration areas are expanding in the coastal east, whereas low-value concentration areas are growing in the northeast. Lastly, the evolution of China's urbanization model suggests a weakening trend of coordination between urbanization and semi-urbanization over the studied decade. Semi-urbanization can be viewed as a special production of China's hukou system, which restricts the permanent settlement of migrants in cities. As such, China's semi-urbanization trend is expected to exhibit a reversed U-shaped pattern as urbanization and citizenization develop.