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Spatial Morphology Evolution Characteristics Analysis of the Resident Population Distribution in Henan, China
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作者 Kaiguang Zhang Hongling Meng +1 位作者 Mingting Ba Danhuan Wen 《Journal of Geoscience and Environment Protection》 2024年第3期163-180,共18页
The population spatial distribution pattern and its evolving pattern play an important role in regional allocation of social resources and production factors, formulation of regional development plans, construction of... The population spatial distribution pattern and its evolving pattern play an important role in regional allocation of social resources and production factors, formulation of regional development plans, construction of a better life society, and promotion of regional economic development. Based on the resident population statistics data of Henan province from 2006 to 2021, with county as the basic study unit, the paper studies the spatial morphology characteristics and its evolution patterns of resident population distribution, by using spatial analysis methods such as population distribution center, standard deviation ellipse, and spatial auto correlation analysis. The results show that: the resident population spatial distribution shows unbalanced state, the population agglomeration areas mainly distribute in the northeast part and north part, where the resident population growth rate is significantly higher than other regions, over time, this trend is gradually becoming significant. The resident population distribution has a trend of centripetal concentration, with the degree and trend of centripetal gradually strengthening. The resident population distribution has obvious directional characteristics, but the significance is not high, the weighted resident population average center is approximately located at (4.13740˚N, 113.8935˚E), and the azimuth of the distribution axis is approximately 11.19˚. The population distribution has obvious agglomeration characteristics, with the built-up areas of Zhengzhou and Luoyang as their centers, where have a significant siphon effect on the surrounding population. The southern and southwestern regions in the province form a relatively stable belt area of Low-Low agglomeration areas. 展开更多
关键词 Resident population spatial distribution spatial Morphology Temporal and spatial Evolution Center Migration Standard Deviation Ellipse spatial Autocorrelation
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Spatial Coupling Relationship and Driving Mechanism of Population and Economy in Rural Areas in Qinling-Daba Mountains,China 被引量:2
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作者 XIAO Jie QIAO Jiajun +2 位作者 HAN Dong LIU Yang PAN Tao 《Chinese Geographical Science》 SCIE CSCD 2023年第5期779-795,共17页
Addressing the issue of the healthy and coordinated development of the population and economic factors in rural areas will not only help consolidate and expand the achievements of poverty alleviation,but will also lay... Addressing the issue of the healthy and coordinated development of the population and economic factors in rural areas will not only help consolidate and expand the achievements of poverty alleviation,but will also lay a foundation for comprehensive rural revitalization.In this paper,the spatial coupling relationship between the population and economic factors in rural areas in the QinlingDaba Mountains,China,is explored to provide a reference for rural revitalization and regional sustainable development in poverty areas.Sixty-eight county units in rural areas in the Qinling-Daba Mountains,as well as the population and economic factors in rural areas,are used to study the spatial coupling relationship between population and economy,as well as the driving mechanism,in rural areas in the Qinling-Daba Mountains from 2010 to 2020.The results show that a population contraction phenomenon occurred in the rural areas in the Qinling-Daba Mountains,and the spatial agglomeration trends of the population and economic factors were consistent.The agglomeration was mainly located in the suburban areas of the municipal area,and the agglomeration degree was significantly higher in these areas than in other areas.In terms of the spatial distribution,the economic development level of the rural areas in the northeastern part of the Qinling-Daba Mountains was generally higher than that in the central and western parts,and the unbalanced trends of the population and economic spatial differentiation in the eastern and western regions were significant.The spatial coupling relationship between the population and economy changed from coordinated development to economic advancement.This was mainly due to the mutual restriction and joint actions of the industrial structure,capital situation,natural environment,policies,and institutional regulations,among which the industrial structure and capital status had significant effects. 展开更多
关键词 rural poverty population distribution economic development pattern spatial coupling influencing factors rural revitalization Qinling-Daba Mountains China
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Patterns of change in the population and spatial distribution of oriental white storks (Ciconia boyciana) wintering in Poyang Lake 被引量:6
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作者 Zhen-Hua WEI Yan-Kuo LI +3 位作者 Peng XU Fa-Wen QIAN Ji-Hong SHAN Xiao-Bin TU 《Zoological Research》 CAS CSCD 2016年第6期338-346,共9页
Using total counts in simultaneous annual surveys, we monitored the population size and spatial distribution of oriental white storks (Ciconia boyciana) wintering in Poyang Lake between 1998 and 2011. Results showed... Using total counts in simultaneous annual surveys, we monitored the population size and spatial distribution of oriental white storks (Ciconia boyciana) wintering in Poyang Lake between 1998 and 2011. Results showed that Poyang Lake wetland is an important wintering ground for oriental white storks, with an annual average population number of 2 305+326. The population sizes in 2004, 2005, 2010, and 2011 were higher than the highest-ever estimate of its global population. In 2005, we recorded 3 789 individuals, which was the maximum population number within the period of 1998-2011. The storks inhabited 52 lakes, with the greatest distance between these lakes being 180.3 km. The storks presented a clustered distribution pattern in the Poyang Lake wetland, irrespective of the number of individuals or occurrence frequencies. Shahu, Dahuchi, Banghu, and Hanchihu were most frequently used lakes and had the largest annual average numbers of storks. There was a significant positive correlation between occurrence frequency and annual average number of storks in the lakes. Most of the lakes important for storks were covered by existing nature reserves, though some lakes outside the reserves were also frequently used. About 64.9%+ 5.5% of the storks were found in nature reserves. In addition, the storks more frequently used and clumped in significantly larger flocks in lakes within nature reserves than lakes outside. 展开更多
关键词 Oriental white stork Poyang Lake population size spatial distribution
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Population Distribution and Dynamics of Quercus liaotungensis, Fraxinus rhynchophylla and Acer mono in Dongling Mountain, Beijing 被引量:48
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作者 吴晓莆 郑豫 马克平 《Acta Botanica Sinica》 CSCD 2002年第2期212-223,共12页
The spatial distribution and population dynamics of Quercus liaotungensis Koidz., Fraxinus rhynchophylla Hance and Acer mono Maxim. were studied in three warm temperate deciduous forests in Dongling Mountain, Beijing.... The spatial distribution and population dynamics of Quercus liaotungensis Koidz., Fraxinus rhynchophylla Hance and Acer mono Maxim. were studied in three warm temperate deciduous forests in Dongling Mountain, Beijing. Clumped distributions appeared in most seedlings (≤0.4 m), short saplings (0.4-1 m) and tall saplings (1-2 m). Random distributions appeared in adults of Q. liaotungensis in Plot 1, F. rhynchophylla in Plot 3. The LSD method was used to discern the differences of different aged population. The class distribution of Q. liaotungensis was nearly a reverse-J shape for Plot 1 and Plot 3, suggesting that the population regenerates continuously. The age-structures of F. rhynchophylla and A. mono in Plot 1 and the test results indicated that they would increase continuously. In Plot 2, the class distribution and the test results showed that all populations would not regenerate continuously. 展开更多
关键词 spatial distribution population structure Quercus liaotungensis
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Research on the Variation of Population Distribution and Its Characteristics Based on Spatial Autocorrelation Method: A Case Study of Poyang Lake Region in Jiangxi Province
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作者 Luo Hui Yang Weichun 《Chinese Journal of Population,Resources and Environment》 2010年第4期76-78,共3页
According to Statistical Yearbook of Jiangxi Province(2001~2006),We analyze the time-space variation of population distribution of Poyang Lake region from the two points of view.The former is quality of population,wh... According to Statistical Yearbook of Jiangxi Province(2001~2006),We analyze the time-space variation of population distribution of Poyang Lake region from the two points of view.The former is quality of population,which involves culture structure,occupational structure,age structure and sex structure of population.The latter is quantity of population,which only involves the amount of population.Furthermore,we can reveal the internal relations and action mechanism of variation of population distribution by analyzing the regional economic development,population urbanization,land use and ecological landscape of Poyang Lake region.It is important to provide help for region planning,ecological landscape planning and environmental protection by correct understanding the man-land relationship of natural-human ecosystem in Poyang Lake region. 展开更多
关键词 population distribution spatial autocorrelation changing characteristics Poyang Lake region
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Study on Simulating Spatial Distribution and Varying Patterns of Urumqi’s Population
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作者 Chen Xuegang Yang Zhaoping Zhang Xiaolei 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第3期31-36,共6页
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
关键词 population spatial INTERPOLATION distribution
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Population structure and distribution pattern of Taxus cuspidata in Muling region of Heilongjiang Province, China 被引量:9
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作者 ZU Yuan-gang CHEN Hua-feng WANG Wen-jie NIE Shao-quan 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期80-82,共3页
An investigation was conducted on distribution pattern, site condition and population structure of yew Taxus cuspidata Sieb. et Zucc. in Muling Forest Bureau of Heilongjiang Province, China in April, 2005. Results sho... An investigation was conducted on distribution pattern, site condition and population structure of yew Taxus cuspidata Sieb. et Zucc. in Muling Forest Bureau of Heilongjiang Province, China in April, 2005. Results showed that yew is mainly distributed under the main storey of natural mixed forest of conifer and broadleaf, the soil moisture content of the yew site is high (40%-60%), the pH value of soil is relatively lower (4.7-5.5), and that the population structure of wild yew is not rational, belonging to the degeneration population, which is one of the reasons leading to the population decline. Although the site conditions of Muling area are suitable for the growth of wild yew, the population of wild yew shows a decline tendency, due to the fact that the middle-sized adult yew trees have been cut, young yews are often grazed by wildlife, and that the trunks of adult yew tend to be hollow. 展开更多
关键词 Taxus cuspidata Sieb. et Zucc. YEW population structure spatial distribution pattern Site conditions
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Population structure and spatial pattern analysis of Quercus aquifolioides on Sejila Mountain,Tibet,China 被引量:2
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作者 Zhiqiang Shen Jie Lu +4 位作者 Min Hua Xiaoqin Tang Xingle Qu Jingli Xue Jiangping Fang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期400-409,共10页
Understanding population structure provides basic ecological data related to species and ecosystems.Our objective was to understand the mechanisms involved in the maintenance of Quercus aquifolioides populations.Using... Understanding population structure provides basic ecological data related to species and ecosystems.Our objective was to understand the mechanisms involved in the maintenance of Quercus aquifolioides populations.Using a 1 ha permanent sample plot data for Q.aquifolioides on Sejila Mountain,Tibet Autonomous Region(Tibet),China,we analyzed the population structure of Q.aquifolioides by combining data for diameter class,static life table and survival curve.Simultaneously,the spatial distribution of Q.aquifolioides was studied using Ripley’s L Function in point pattern analysis.The results showed:(1) Individuals in Q.aquifolioides populations were mainly aggregated in the youngest age classes,that accounted for94.3% of the individuals; the older age classes had much smaller populations.Although the youngest age classes(ClassesⅠ and Ⅱ) had fewer individuals than Class Ⅲ,the total number of individuals in classes Ⅰ and Ⅱ was also greater than in classes Ⅳ to Ⅸ.In terms of tree height,fewsaplings,more medium-sized saplings and few large-sized trees were found.The diameter class structure of Q.aquifolioides populations formed an atypical ‘pyramid’type; the population was expanding,but growth was limited,tending toward a stable population.(2) Mortality of Q.aquifolioides increased continuously with age; life expectancy decreased over time,and the survivorship curve was close to a Deevey I curve.(3) The spatial distribution pattern of Q.aquifolioides varied widely across different developmental stages.Saplings and medium-sized tree showed aggregated distributions at the scales of 0–33 m and 0–29 m,respectively.The aggregation intensities of saplings and medium-sized trees at small scales were significantly stronger than that of large-sized trees.However,large-sized trees showed a random distribution at most scales.(4) No correlation was observed among saplings,medium-and large-sized trees at small scales,while a significant and negative association was observed as the scale increased.Strong competition was found among saplings,medium-and large-sized trees,while no significant association was observed between medium-and largesized trees at all scales.Biotic interactions and local ecological characteristics influenced the spatial distribution pattern of Q.aquifolioides populations most strongly. 展开更多
关键词 Point pattern analysis population structure Quercus aquifolioides Sejila Mountain spatial distribution pattern
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Exploring Urban Population Forecasting and Spatial Distribution Modeling with Artificial Intelligence Technology 被引量:2
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作者 Yan Zou Shaoliang Zhang Yanhai Min 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第5期295-310,共16页
The high precision population forecasting and spatial distribution modeling are very important for the theory and application of population sociology,city planning and Geo-Informatics.However,the two problems need to ... The high precision population forecasting and spatial distribution modeling are very important for the theory and application of population sociology,city planning and Geo-Informatics.However,the two problems need to be solved for providing the high precision population information.One is how to improve the population forecasting precision of small area(e.g.,street scale);another is how to improve the spatial resolution of urban population distribution model.To solve the two problems,some new methods are proposed in this contribution.(1)To improve the precision of small area population forecasting,a new method is developed based on the fade factor and the slide window.(2)To improve the spatial resolution of urban population distribution model,a new method is proposed based on the land classification,public facility information and the artificial intelligence technology.For validation of the proposed methods,the real population data of 15 streets in Xicheng district,Beijing,China from 2010 to 2016,the remote sensing images and the public facility data are collected and used.A number of experiments are performed.The results show that the spatial resolution of proposed model reaches 30m*30m and the forecasting precision is better than 5%using the proposed method to forecast the population of 15 streets in Xicheng district in the next four years. 展开更多
关键词 population forecasting spatial distribution CELLULAR AUTOMATA MULTI-AGENT system
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Using a GIS Tool to Map the Spatial Distribution ofPopulation for 2010 in the State of Mexico, Mexico 被引量:2
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作者 Roberto Franco-Plata L. Ricardo Manzano-Solís +3 位作者 Miguel A. Gómez-Albores José I. Juan-Pérez Noel B. Pineda-Jaimes Araceli Martínez-Carrillo 《Journal of Geographic Information System》 2012年第1期1-11,共11页
The present document describes the experience of using a Geography Information System (GIS) tool to map the spatial distribution of the population of the State of Mexico, Mexico, for 2010. Prior to the development of ... The present document describes the experience of using a Geography Information System (GIS) tool to map the spatial distribution of the population of the State of Mexico, Mexico, for 2010. Prior to the development of the experience, dif- ferent projects, tools and products, which offered cartographic representations of the population, were presented, se- lecting one that was developed to function in Idrisi Taiga GIS. Likewise, the GIS tool and the process followed to apply it to a case study in the State of Mexico are described. The result is a raster image that shows the distribution of the population on the analyzed state, offering the possibility to identify the zones where the population concentrates and disperses and to produce an opinion from a geographic point of view on what the origin of these distribution patterns is. Among the conclusions from the analysis of results, distinguishable are the applications that the obtained image can have;for instance, the population can be estimated by basins or risk zones by only adding the values of the cells inside these zones. It is also concluded that the degree of detail expressed by the spatial distribution image of the population will depend on several factors, among them the scale and resolution of the input information and the resolution fixed for the output information. 展开更多
关键词 spatial distribution of the population Idrisi TAIGA GIS TOOL State of Mexico
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An Analysis on the Spatial Distribution of Population Aging Pressure in China
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作者 YangWangzhou Dong Suocheng +1 位作者 Wu Youde Luo Renbo 《Chinese Journal of Population,Resources and Environment》 2012年第1期122-128,共7页
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
关键词 population aging comprehensive pressure index spatial distribution factor analysis
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Population Spatial Distribution Based on Luojia 1-01 Nighttime Light Image:A Case Study of Beijing
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作者 SUN Lu WANG Jia CHANG Shuping 《Chinese Geographical Science》 SCIE CSCD 2021年第6期966-978,共13页
With the continuous development of urbanization in China,the country’s growing population brings great challenges to urban development.By mastering the refined population spatial distribution in administrative units,... With the continuous development of urbanization in China,the country’s growing population brings great challenges to urban development.By mastering the refined population spatial distribution in administrative units,the quantity and agglomeration of population distribution can be estimated and visualized.It will provide a basis for a more rational urban planning.This paper takes Beijing as the research area and uses a new Luojia1-01 nighttime light image with high resolution,land use type data,Points of Interest(POI)data,and other data to construct the population spatial index system,establishing the index weight based on the principal component analysis.The comprehensive weight value of population distribution in the study area was then used to calculate the street population distribution of Beijing in 2018.Then the population spatial distribution was visualize using GIS technology.After accuracy assessments by comparing the result with the WorldPop data,the accuracy has reached 0.74.The proposed method was validated as a qualified method to generate population spatial maps.By contrast of local areas,Luojia 1-01 data is more suitable for population distribution estimation than the NPP/VIIRS(Net Primary Productivity/Visible infrared Imaging Radiometer)nighttime light data.More geospatial big data and mathematical models can be combined to create more accurate population maps in the future. 展开更多
关键词 Luojia1-01 nighttime light image principal component analysis points of interest landuse type data population spatial distribution
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Simulation Analysis on Spatial Pattern of Urban Population in Shenyang City,China in Late 20th Century 被引量:5
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作者 QIN Zhiqin ZHANG Pingyu 《Chinese Geographical Science》 SCIE CSCD 2011年第1期110-118,共9页
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
关键词 population distribution urban spatial structure simulation analysis Shenyang City
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Origin Distribution Patterns and Floating Population Modeling:Yiwu City as a Destination 被引量:3
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作者 LI Hongsheng WANG Yingjie HAN Jiafu 《Chinese Geographical Science》 SCIE CSCD 2012年第3期367-380,共14页
Existing quantitative migration studies are mainly at the inter-region or inter-province level for lacking of detailed geo-referenced migration data.Meanwhile,few of them integrate explorative spatial data analysis an... Existing quantitative migration studies are mainly at the inter-region or inter-province level for lacking of detailed geo-referenced migration data.Meanwhile,few of them integrate explorative spatial data analysis and spatial regression model into migration analysis.Based on aggregated registered floating population data from 2005 to 2008,the phenomena that population floating to Yiwu City in Zhejiang Province is analyzed at the provincial and county levels.The spatial layout of Yiwu's pull forces is proved as a V-shaped pattern excluding Sichuan Province based on map visualization method.Using the migration ratio in 2007 as an explanatory variable,two models are compared using ordinary least square,spatial error model and spatial lag model methods for county-level data in Jiangxi and Anhui provinces.The model with migration stock provides an improved fitting over the model without migration stock according to the model fitting results.The floating population flocking into Yiwu City from Jiangxi is determined mostly by migration stock while the determinant factors are migration stock and distance to Yiwu City for Anhui.The distance-decay effect is true for migration flow from Anhui to Yiwu City while the distance rule is not confirmed in Jiangxi with the best fitting model.The correlation between per capita net income of rural labor forces and migration ratio is not significant in Jiangxi and significant but at the 0.1 level only in Anhui.Further analysis shows that the distance,income and man-land ratio are important factors to explain population floating at earlier stage.However,as the dynamic population floating process evolves,the determinant factor would be migration stock. 展开更多
关键词 floating population origin distribution visualization spatial regression model Yiwu City GIS
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Population Distribution and Influencing Factors Based on ESDA 被引量:3
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作者 Lv Chen Fan Jie Sun Wei 《Chinese Journal of Population,Resources and Environment》 2012年第3期47-53,共7页
Based on the exploratory spatial data analysis (ESDA) technique and geographic information system (GIS) platform, with statistic data of counties in 2005, this paper confirms that there is a large population densi... Based on the exploratory spatial data analysis (ESDA) technique and geographic information system (GIS) platform, with statistic data of counties in 2005, this paper confirms that there is a large population density gap between counties in 2005 because the Gini coefficient is 0.55. Population distribution does not change a lot during the past decades, and the southeast China is still much more densely populated than the northwest China. The global spa- tial autoeorrelation of population distribution is obvious because Moran's I scores 0.42 and local spatial autocorrelation is partly significant. Climate and elevation are still the main natural influ- encing factors. Meanwhile industrial structure and transportation significantly influence population distribution. Different combinations of natural factors have different effects on population distribution. For a long term, climate and terrain factor stability affect population distribution. But its influence will be weakened by progress of technology. Economic development is the main factor that changes population distribution for a short term. 展开更多
关键词 population distribution geographic information system (GIS) spatial autocorrelation influencing factors
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Spatio-temporal characteristics of population and economy in transitional geographic space at the southern end of"Hu Huan-yong Line" 被引量:2
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作者 DENG Wei CHENG Yu-fang +3 位作者 YU Huan PENG Li KONG Bo HOU Yu-ting 《Journal of Mountain Science》 SCIE CSCD 2022年第2期350-364,共15页
"Hu Huan-yong Line(Hu Line)"depicts a geographical pattern of China’s population distribution.Its essence is the regionality of humanland relationship and reflects basic characteristics and laws of human be... "Hu Huan-yong Line(Hu Line)"depicts a geographical pattern of China’s population distribution.Its essence is the regionality of humanland relationship and reflects basic characteristics and laws of human beings’adaptation to the natural environment.With the development of the times and the progress of modern science and technology,especially the rapid urbanization and construction of transportation network system in China,the connection between economic and geographical space has been continuously strengthened.The geographical transition zones from mountain areas to plains,i.e.,transitional geographical space,have promoted the changes in human-land relationships through population migration and agglomeration.Taking Sichuan-Yunnan provinces at the southern end of Hu Line as study area,this study analyzed the spatial correlation between population distribution and economy in this region,explored the pattern of geographical agglomeration and deagglomeration,and explained the changing characteristics of humanland relationship in transitional geographic space using global Moran’s I index,global regression model(GRM)and geographically weighted regression(GWR).The results show that population and Gross Domestic Product(GDP)have significant spatial dependence to this region,with obvious aggregation in geographical distribution and positive autocorrelation;comparing with the general least square model,the GWR model incorporating spatial effect was more suitable for revealing the distribution characteristics of geographical elements,with fine results and better fitting;the spatial model of population and GDP as well as the spatio-temporal evolution model of their changes,all of them strongly indicated that Normalized Difference Vegetation Index(NDVI)and road density were important factors governing the spatial differentiation of population and economy;under the rapid development of regional economy and continuous evolution of urban-rural relations,rural transformation and spatial reconstruction promoted the change of population migration and agglomeration. 展开更多
关键词 Hu Huan-yong Line spatial correlation Geographically weighted regression population distribution Transitional geographic space
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Spatial pattern dynamics among co-dominant populations in early secondary forests in Southwest China 被引量:5
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作者 Yuanfa Li Minghui Li +3 位作者 Angang Ming Hongxiang Wang Sufang Yu Shaoming Ye 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第4期1373-1384,共12页
The canopy of subtropical natural forests usually consists of several co-dominant populations(CDPs),which play a crucial role in forest structure,formation of the forest environment,and ecological function.However,lit... The canopy of subtropical natural forests usually consists of several co-dominant populations(CDPs),which play a crucial role in forest structure,formation of the forest environment,and ecological function.However,little attention has been given to changes in spatial patterns in CDPs during natural succession.Cyclobalanopsis glauca(Thunb.)Oerst.,Quercus variabilis Blume,and Pinus yunnanensis var.tenuifolia W.C.Cheng & Y.W.Law are canopy species that form CDPs in zonal forests along the Nanpan River in southwest China.We used the g(r) function and its bivariate distribution model,g_(12)(r),which is based on distances between pairs of points,to explore the dynamics of the three CDP species with respect to distribution patterns and spatial correlations in two secondary forests(one 30-year-old forest [30-YF] and one 57-year-old forest [57-YF]).The following key results were obtained:(1) there was a clumped pattern in the 30-YF,but the intensity of aggregation varied among populations and life stages.The distribution pattern gradually shifted to become random with longer succes sion time(i.e.,30-YF vs.57-YF),expansion of the observation scale(r=0-20 m),and at later life stages.(2) Aside from the mid-sized C.glauca trees and large P.yunnanensis trees,the trees repulsed each other at certain scales(r=0-2,5-6,11-12,14-16 m) in the 30-YF.Almost all of the life stages in the CDPs were independently correlated.This independent correlation was exacerbated by a longer succession time.(3) An increase in life stages and longer succession also promoted independent changes in intraspecific correlations.(4) Intraspecific correlations were stronger than interspecific correlations.Our results showed that reducing exclusive competition is essential to coexistence in CDPs.Inter-and intra-specific repulsion may occur at the same time,but intraspecific repulsion was the main driving force behind the random distributions and independent correlations. 展开更多
关键词 Co-dominant populations COMPETITION Secondary forest spatial correlations distribution patterns
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The spatial properties of atomic Raman-Nath diffraction
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作者 李利平 张利彦 +2 位作者 宋佩君 谢小涛 李伟斌 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第8期2428-2432,共5页
This paper obtains the exact analytical solution of atomic Raman-Nath diffraction in the coordinate representation and discusses the influence of different initial conditions and detunings on the atomic spatial popula... This paper obtains the exact analytical solution of atomic Raman-Nath diffraction in the coordinate representation and discusses the influence of different initial conditions and detunings on the atomic spatial population distribution. The phase difference between the dipole matrix element and initial atomic population may influence the atomic spatial population distribution after diffraction, which has never been discussed before as far as we know. It offers a method to measure the phase by the spatial population distribution, which is interesting in the study of quantum optics. 展开更多
关键词 Raman-Nath diffraction spatial population distribution phase difference coordinate representation
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Study of the Urban Coordinated Development Capability Index in the Yangtze River Economic Belt
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作者 ZENG Gang YANG Shuting WANG Fenglong 《Journal of Landscape Research》 2020年第2期41-48,共8页
Coordinated development is a major concern in the construction strategy of the Yangtze River Economic Belt (YREB).However,there were few studies which have quantitatively measured the level of coordinated development ... Coordinated development is a major concern in the construction strategy of the Yangtze River Economic Belt (YREB).However,there were few studies which have quantitatively measured the level of coordinated development in the YREB.This paper aimed to propose an comprehensive index system of coordinated development based on the theories of growth pole and complex ecosystem and new guidelines of development from the central government.The index system was composed by 18 indicators within 4 domains including economic development,technology & innovation,communication & transportation,and ecological protection.The scores of coordinated development capability of the 110 prefecture-level cities in the YREB were calculated and examined using natural break point analysis,spatial autocorrelation analysis and rank-size analysis.It was shown that Shanghai,Nanjing and Wuhan were leading the coordinated development in the YREB.Generally,the scores of coordinated development capability were higher in the eastern region of the YREB,in which the cities performed well in the domains of economic development,technology & innovation and communication & transportation yet showed poor performance in ecological protection.Most cities in the middle reaches of Yangtze river ranked in the middle in the YREB in all the domains,except the provincial capitals.The western region of the YREB got the lowest score in the coordinated development capability besides the largest cities such as Chongqing,Chengdu,Kunming and Guiyang.The correlation coefficients between ecological protection and other domains were very low,suggesting that few cities have achieved a win-win situation between environment protection and socio-economic development.We suggested 3 ways to promote coordinated development in the YREB:establish multi-level institutional designs;enhance the innovation in green industries;and strengthen the joint prevention and control of ecological risks. 展开更多
关键词 The YANGTZE River economic Belt(YREB) COORDINATED Development Capability spatial distribution RANK-SIZE distribution Correlation Coeffi cient
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基于决策树模型的城市人群稳态分布预测实证——以泉州湾片区为例
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作者 杨俊宴 张钟虎 +2 位作者 史宜 顾杰 郑坤仪 《城市规划》 CSCD 北大核心 2024年第2期45-56,共12页
基于预测的城市人群时空变化特征对城市空间资源进行配置是城市规划的重要工作,城市人口在不同的空间中快速变迁移动,具有非均衡分布的特点。这种人群非均衡分布的时空变化具有一定的规律性,即稳态分布。本文基于LBS数据以及建成环境的... 基于预测的城市人群时空变化特征对城市空间资源进行配置是城市规划的重要工作,城市人口在不同的空间中快速变迁移动,具有非均衡分布的特点。这种人群非均衡分布的时空变化具有一定的规律性,即稳态分布。本文基于LBS数据以及建成环境的多源异构大数据,选取4大类36小类指标,采用智能决策树模型构建城市人群稳态分布的预测模型。对于泉州的实证发现,预测模型的准确度达84.32%,具有较高的准确性和依据,其内在理论依据是城市人群在空间上的规律性时空活动,能够为未来的城市规划提供决策参考。 展开更多
关键词 人群时空分布 多情景预测 规划评估 随机森林决策树
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