Phase is a fundamental resource for optical imaging but cannot be directly observed with intensity measurements.The existing methods to quantify a phase distribution rely on complex devices and structures and lead to ...Phase is a fundamental resource for optical imaging but cannot be directly observed with intensity measurements.The existing methods to quantify a phase distribution rely on complex devices and structures and lead to difficulties of optical alignment and adjustment.We experimentally demonstrate a phase mining method based on the so-called adjustable spatial differentiation,by analyzing the polarization of light reflection from a single planar dielectric interface.Introducing an adjustable bias,we create a virtual light source to render the measured images with a shadow-cast effect.From the virtual shadowed images,we can further recover the phase distribution of a transparent object with the accuracy of 0.05λRMS.Without any dependence on wavelength or material dispersion,this method directly stems from the intrinsic properties of light and can be generally extended to a broad frequency range.展开更多
By using digitized land use maps of Beijing in 1982, 1992 and 1997 and employing GIS spatial analysis techniques, this paper conducts an empirical study on the spatial differentiation and spatial patterns of urban lan...By using digitized land use maps of Beijing in 1982, 1992 and 1997 and employing GIS spatial analysis techniques, this paper conducts an empirical study on the spatial differentiation and spatial patterns of urban land use growth in Beijing in the period of 1982–1997. It is observed that urban land use growth in Beijing went beyond the control of urban planning, in terms of the extraordinary high growth rate and undesired spatial pattern. The rate of urban expansion after 1982, which was predominated by growth of industrial land, was extraordinary high compared to its historical period. While its growth centers have been actively shifting toward the northern part, rather than toward the southern and eastern parts as designated by the latest General Plan (1991–2010) of Beijing, its spatial pattern of urban land use growth in general was in distinct concentric sprawl, which seriously violated the General Plan of Beijing.展开更多
In this study, housing prices data for residential quarters from the period 2001-2012 were used and Global Differentiation Index （GDI） was established to measure the overall differentiation trend in housing prices i...In this study, housing prices data for residential quarters from the period 2001-2012 were used and Global Differentiation Index （GDI） was established to measure the overall differentiation trend in housing prices in Yangzhou City, eastern China. Then the influence of the natural landscape and environment on prices of global housing market and housing submarkets was evaluated by the hedonic price model. The results are shown as follows. （1） There have been increasing gaps among housing prices since 2001. In this period, the differentiation trend has shown an upward fluctuation, which has been coupled with the annual growth rate of housing prices. （2） The spatial distribution of residential quarters of homogenous prices has changed from clustered in 2001 into dispersed in 2012. （3） Natural landscape and environmental externalities clearly influence spatial differentiation of housing prices. （4） In different housing submarkets, the influence of natural landscape and environmental eternalities are varied. Natural landscape characteristics have significant impact on housing prices of ordinary commercial houses and indemnificatory houses, while the impact of environmental characteristics have obvious influence on housing prices of cottages and villas.展开更多
GIMMS NDVI database and geo-statistics were used to depict the spatial distribution and temporal stability of NDVI on the Mongolian Plateau.The results demonstrated that:(1) Regions of interest with high NDVI indices ...GIMMS NDVI database and geo-statistics were used to depict the spatial distribution and temporal stability of NDVI on the Mongolian Plateau.The results demonstrated that:(1) Regions of interest with high NDVI indices were distributed primarily in forested mountainous regions of the east and the north,areas with low NDVI indices were primarily distributed in the Gobi desert regions of the west and the southwest,and areas with moderate NDVI values were mainly distributed in a middle steppe strap from northwest to southeast.(2) The maximum NDVI values maintained for the past 22 years showed little variation.The average NDVI variance coefficient for the 22-year period was 15.2%.(3) NDVI distribution and vegetation cover showed spatial autocorrelations on a global scale.NDVI patterns from the vegetation cover also demonstrated anisotropy;a higher positive spatial correlation was indicated in a NW-SE direction,which suggested that vegetation cover in a NW-SE direction maintained increased integrity,and vegetation assemblage was mainly distributed in the same specific direction.(4) The NDVI spatial distribution was mainly controlled by structural factors,88.7% of the total spatial variation was influenced by structural and 11.3% by random factors.And the global autocorrelation distance was 1178 km,and the average vegetation patch length(NW-SE) to width(NE-SW) ratio was approximately 2.4:1.0.展开更多
The urban vulnerability poses a serious challenge to achieving sustainable devel- opment. With the concentration of the population and the economy, cities must manage the higher frequencies and risks of various hazard...The urban vulnerability poses a serious challenge to achieving sustainable devel- opment. With the concentration of the population and the economy, cities must manage the higher frequencies and risks of various hazards and are becoming more vulnerable. Re- search on the assessment and regulatory control of urban vulnerability is of great significance for both urbanization quality improvement and sustainable development in China or other countries in the world. Because of the complexity of cities and vulnerability concepts, existing studies have focused on different aspects of urban vulnerability. And the research content of urban vulnerability is scattered and relatively independent, leading to a lack of comparability among the research data and resulting in tremendous difficulties in summarizing the conclu- sions through comparison of independent research data. Therefore the goal of this study was to construct urban vulnerability index （UV/） from the perspective of sustainable development that could assess urban vulnerability comprehensively. In this study, we selected 10 subin- dexes involving 36 specific parameters from four aspects （resources, eco-environmental sys- tems, economics, and social development） to construct a comprehensive index system. We also established the standard values of measurements. Then we take 288 prefecture-level cities in China as a study area and evaluate its overall urban vulnerability and its spatial differentiation. Results indicate that urban vulnerability of China has a remarkable spatial differentiation of both ＂gradient distribution＂ and ＂clustered distribution＂; the extent of urban vulnerability corresponds to city size, the bigger the city, the lower its vulnerability; re- source-based cities are more vulnerable than comprehensive cities; a city＇s economic growth rate does not reflect the extent of its urban vulnerability. Further, we offer a few suggestions to cope with urban vulnerability in China.展开更多
This study analyzes the spatial patterns and driving forces of housing prices in China using a 2,872-county dataset of housing prices in 2014.Multiple theoretical perspec-tives on housing demand,supply,and market,are ...This study analyzes the spatial patterns and driving forces of housing prices in China using a 2,872-county dataset of housing prices in 2014.Multiple theoretical perspec-tives on housing demand,supply,and market,are combined to establish a housing price model to explore the impact of land prices on housing prices.The relative impacts of land prices on housing prices at different administrative levels are then analyzed using the geo-graphical detector technique.Finally,the influencing mechanism of land prices on housing prices is discussed.The main conclusions are as follows.(1)Housing prices have a pyra-mid-ranked distribution in China,where higher housing prices are linked to smaller urban populations.(2)Land prices are the primary driver of housing prices,and their impacts on housing prices vary over different administrative levels.To be specific,the effect of land prices is the strongest in the urban districts of provincial capital cities.(3)The internal influ-ence mechanisms for land prices driving housing prices are:topographic factors,urban con-struction level,the agglomeration degree of high-quality public service resources,and the tertiary industrial development level.The urban land supply plan(supply policies)is the in-trinsic driver that determines land prices in cities;through supply and demand,cost,and market mechanisms,land prices then impact housing prices.展开更多
The policy of land transfer has greatly influenced the macro economy of China with the commencement of another innovation of land use system. Therefore, it is urgent to put forward some rational and feasible suggestio...The policy of land transfer has greatly influenced the macro economy of China with the commencement of another innovation of land use system. Therefore, it is urgent to put forward some rational and feasible suggestions for local government to manage the market of land transfer. Moreover, it is important in the field of study on agricultural land use change to analyze the spatial differentiation and structural specification of land transfer, which are caused by rural households＇ behavior. This paper selected I l factors covering four aspects of rural households＇ family structure, family location, family income structure and the natural quality of land resources, all of which influence the behavior differentiation of rural households, to establish the index model indicating spatial differentiation of land transfer. Results show that the spatial differentiation of land transfer can be divided into four degrees and three categories through analyzing rural households＇ questionnaires from Shanghai, Nanjing and Taizhou in the Changjiang （Yangtze） River Delta. Since up to 80% of rural households belong to middle degrees, it can be concluded that the rural land market develops evenly in the study areas. And it is also indicated that the natural quality of land resources and the maximum income of rural land are most important factors influencing the spatial differentiation of land transaction. Considering different factors, the countermeasures can be carried out to enhance the spatial differentiation of land transfer so as to promote economic development and social security of rural China. All in all, both micro- factors and macro-factors influencing rural households＇ behavior of rural land transfer should be taken into account in order to make spatial differentiation and structural specification of rural land transfer notable.展开更多
The scientific analyses of the spatial patterns of regional eco-environment livability,along with the explorations of the correlations between ecoenvironments and population and economic activity distributions,are of ...The scientific analyses of the spatial patterns of regional eco-environment livability,along with the explorations of the correlations between ecoenvironments and population and economic activity distributions,are of major significance in the guidance of the coordinated development between social economies,natural resources,and environments.In this study,the topography,climate,hydrology,land cover,air quality,and the dangers presented by natural hazards in the study area were investigated in order to establish an evaluation model for the regional eco-environmental livability.Then,the observed spatial patterns and regional differences in the eco-environmental livability,as well as their relationships with the distributions of population and economic activities in Zhejiang Province,were investigated.The results showed that the ecoenvironmental livability in Zhejiang Province displayed a gradual decreasing trend from southwest to northeast,as well as from the mountains to the hills,valleys,and plains areas.During the compartmentalization of the eco-environmental livability,it was observed that the lowest livable area covered the largest population,accounting for approximately 29.64%of the total population in the study area.The higher livable areas covered the widest land areas,accounting for approximately 26.15%of the total area.Moreover,it was found that the eco-environmental livability in the mountain areas was higher than that in the plain areas in Zhejiang Province.Furthermore,the ecoenvironmental livability was found to have a significant exponential relationship with the population and GDP densities of Zhejiang Province,with the R^2 of the curve-fittings reaching 0.835 and 0.656,respectively.However,it was determined that the coefficient of the exponential function was negative,which indicated that a strong negative relationship existed between the eco-environmental livability and densities of the population and economic activities.It was assumed that the impacts of anthropogenic factors were the fundamental causes of this negative correlation.This study introduced two new factors(air quality and natural hazards)into the evaluation framework of eco-environmental livability.As a result,a more comprehensive model was established for the evaluation of eco-environmenta livability in certain segments of the study area Additionally,the correlation between ecoenvironment livability and human activities was discussed in-depth,which can potentially provide theoretical and practical guidance for the implementation of eco-livability in China,and possibly even those of other vast developing countries.展开更多
The spatial distribution of vegetation in Qaidam Basin was analyzed using GIMMS（Global Inventory Modeling and Mapping Studies） /NDVI（Normalized Difference Vegetation Index） data set from January 1982 to December 2...The spatial distribution of vegetation in Qaidam Basin was analyzed using GIMMS（Global Inventory Modeling and Mapping Studies） /NDVI（Normalized Difference Vegetation Index） data set from January 1982 to December 2006.Based on the data of precipitation,terrain,stream systems,land use and the map of vegetation distribution in Qaidam Basin,we studied the factors influencing the spatial distribution of vegetation.The results showed that the vegetation was generally low in Qaidam Basin and there was a clear semi-ring structure from southeast to northwest.In some areas,the existence of rivers,lakes and spring belts turned this semi-ring structure into a non-continuous state and formed distinct bright spots and continuous linear features.There were four main factors that affected the spatial distribution of vegetation coverage in Qaidam Basin,i.e.,precipitation,hydrological conditions,altitude and human activities.Precipitation and altitude have a correlation and determine the basic pattern of vegetation distribution in Qaidam Basin.The impacts of hydrological conditions and human activities were mainly embodied in partial areas,and often broke the pattern of vegetation distribution dominated by precipitation and altitude.展开更多
Stable isotope values of oxygen （180） and hydrogen （2H） of surface waters were used to study the origin and environmental significanees in the Issyk-Kul basin of Kyrgyzstan in Central Asia, which is the most impor...Stable isotope values of oxygen （180） and hydrogen （2H） of surface waters were used to study the origin and environmental significanees in the Issyk-Kul basin of Kyrgyzstan in Central Asia, which is the most important intermountain basin in the modern Tien Shan orogen. This study is the first analysis of hydrochemical spatial differentiation in the stable isotopes of surface waters in this watershed. 75 samples were collected from rivers, springs, lakes, rain and snow during the rainy season in July and August of 2o16. Stable isotopes of 180 and 2H were studied for all samples, and cation ratios （Sr/Ca and Mg/Ca） were also determined for lake water samples. Stable isotope values from precipitation scattered around the Local Meteoric Water Line （determined from Urumqi Station of the global network of isotopes in precipitation （GNIP））, together with values of the Deuterium excess parameter （d） from 15.3‰ to 30.5‰, with an average of 19.8‰, indicating that the moisture sources are primarily from regions with low relative humidity. The 8180 and 52H values were significantly different between the river and lake samples, indicating that regional evaporation caused the isotopic enrichment of lake water. Geospatial autocorrelation, measured by Moran＇s I coefficient, indicated weak spatial autocorrelation within stable isotopes of oxygen and hydrogen in the surface waters of the studied area, which is primarily an effect of climate during the water chemistry evolution. The cation ratios Sr/Ca and Mg/Ca in lake water samples were not correlated with the concentration of total dissolved solids, but did show correlation with stable isotopic values, which is significant for paleoenvironmental reconstruction.展开更多
The protection and development problems in ethnic minority villages have received great attention from the Chinese government.This study aims to systematically identify the spatial differentiation characteristics of e...The protection and development problems in ethnic minority villages have received great attention from the Chinese government.This study aims to systematically identify the spatial differentiation characteristics of ethnic minority villages and their influencing factors in Guizhou Province.Applying ArcGIS and GeoDa,a total of 1,014 ethnic minority villages in the four batches announced by the Ethnic and Religious Affairs Commission of Guizhou Province(272in the first batch,240 in the second batch,255 in the third batch,and 247 in the fourth batch)served as the research objects.Utilizing the economic development data in Guizhou Statistical Yearbook 2018-2020 for analysis,the coupling calculation of the spatial layout and economic development level of ethnic minority villages was conducted.The results indicate that the number of ethnic minority village points varies in spatial distribution with remarkable agglomeration.The spatial equilibrium distribution of ethnic minority villages in the province is imbalanced.The kernel density is characterized by independent single kernel centers with sporadic distributions of subcenters and an echelon distribution whole.The spatial complexity distribution indicates that ethnic minority villages in Guizhou possess unequal characteristics,and the fractal of the system structure is more complicated.The findings reveal that the spatial distribution of ethnic minority characteristic villages in Guizhou is highly consistent with that of ethnic minorities in Guizhou.The distribution is the combined results of geographical factors and socialeconomic factors.Most ethnic minority characteristic villages in Guizhou Province are located in areas with complex terrain,inconvenient transportation,and relatively backward economic development.Based on the current geospatial distribution of ethnic minority villages,the present study will provide remarkable implications for the Chinese government to implement the Rural Revitalization Strategy from several key aspects.The Chinese government should establish a protection and development mechanism in ethnic minority villages and strive to enhance the characteristics of ethnic cultural industries.Meanwhile,the"integration of culture and tourism"should be taken as the development strategy while the industry should support rural economic development and help eliminate poverty.This is of crucial practical significance to national unity and rural revitalization in China.展开更多
Coal is a basic resource and its use guarantees the development of national economies and human society. Thus, coal transportation is an important part of China's overall transportation system. In this system, por...Coal is a basic resource and its use guarantees the development of national economies and human society. Thus, coal transportation is an important part of China's overall transportation system. In this system, ports are the vital transit nodes. This study considered coastal ports in China and analysed the evolution of coal transportation from 1973 to 2013. We focused on the spatial pattern of coal loading and unloading, and summarized the main characteristics and development of the processes. Then, we examined the volumes of coal transported and regional changes in these amounts using mathematical models and indicators. Finally, we analysed the specialized function and spatial differentiation of the ports involved in coal transportation to reveal their spatial relationship and temporal evolution. We found that the spatial pattern of coal transportation changed from "south input and north output" to "all input and north output". However, the prominent ports used for coal unloading are still concentrated in areas south of the Yangtze River. Coal loading is concentrated on the west bank of Bohai Bay. In addition, some ports around Bohai Bay, such as Dandong, Dalian, Yantai, and Qingdao, changed from traditional coal loading ports to unloading ports. This study further developed the theory of transport geography, and improved our understanding of China's coal transportation system.展开更多
The Changtang Plateau(CTP)in Qinghai-Tibet Plateau of China is one of the top-10 uninhabited areas with the most important ecological value in the world.It is of great academic and practical significance to carry out ...The Changtang Plateau(CTP)in Qinghai-Tibet Plateau of China is one of the top-10 uninhabited areas with the most important ecological value in the world.It is of great academic and practical significance to carry out research on human settlements in the marginal zones of the uninhabited areas to promote harmonious coexistence between humans and nature on the CTP.Using high-definition remote-sensing images to visually interpret and identify settlement-patch data,combined with field investigations,this study explores the spatial characteristics of human settlements in Shuanghu and Nyima counties and their responses to natural and socioeconomic conditions in the hinterland of the CTP.Findings reveal that the scale of human settlements on the CTP is extremely small,and density is very sparse.Settlements on the CTP primarily consist of several households,with some containing more than a dozen households,or are sub-village scale.Socioeconomic development is low and socioeconomic factors have a weak influence on the settlement layout on the CTP.Natural factors are the core elements affecting the layout of human settlements on the CTP.Settlements tend to occur on low mountains,gentle slopes,and areas with high average annual temperatures.Careful settlement site selection can help to mitigate the impact of natural disasters.To meet the needs of grazing,settlement layouts must typically have a high-quality grassland orientation.Riverbanks are key settlement areas,and settlement sites are often far away from alpine salt lakes.The characteristics of settlements on the CTP and their responses to environmental conditions significantly differ from those of human settlements in low-altitude inland areas.展开更多
Village classification is the first step to implementing China’s rural revitalization(RR)strategy,and understanding the geographic differences in the distribution of village types helps to grasp the pathway of their ...Village classification is the first step to implementing China’s rural revitalization(RR)strategy,and understanding the geographic differences in the distribution of village types helps to grasp the pathway of their unique development.This study spatialized9250 villages in Jilin Province(divided into six types)of China,and their distribution characteristics and influencing factors were examined using methods such as kernel density estimation,Ripley’s K function,the co-location quotient,and Geodetector.The results indicate that the spatial distribution balance and density of village types are different.All types of villages show an agglomeration distribution pattern,but the scale and intensity vary.There is a strong spatial association between agglomerative promotion(AP)and stable improvement(SIm)villages,as well as between characteristic protection(CP)and prospering frontier and enriching people(PE)villages.The factors affecting their distribution include terrain undulation,the percentage of arable land,the distance to the county town,road network density,population density,gross domestic product(GDP),and industrial enterprise density.The influencing factors for the distribution of village types are closely related to the function of each village.Based on the differences in the spatial distribution and influencing factors of different village types,policy suggestions are given for classified development.展开更多
Submarine micro-geomorphology is a geo-morphological type occurring in shallow and surface areas of seabed.The combined relationships and distribution of the micro-geomorphology indirectly reflect coupling relationshi...Submarine micro-geomorphology is a geo-morphological type occurring in shallow and surface areas of seabed.The combined relationships and distribution of the micro-geomorphology indirectly reflect coupling relationships among the sediment deposition,dynamic environment,and geomorphologic evolution.Spatial differentiation and dynamic changes in micro-geomorphology were studied based on acoustic data interpretation from a wide range(3200 km^(2))of the Huanghe(Yellow)River delta(HRD).The combination of the sub-bottom profiler and the side-scan sonar methods allowed for the identification of submarine shallow micro-geomorphologic types,as well as their scale and spatial distributions.There were seven typical micro-geomorphologic features in the shallow and surface areas of the HRD,including buried ancient channels,stratigraphic disturbances,scour troughs,sand waves,pits,erosional remnants,and sand spots.The coupling and superposition of the sediment,sediment characteristics,seabed scouring and silting,and hydrodynamic conditions of the Huanghe River had combined effects on the patterns of micro-geomorphologic types,characteristics,and ranges.From the perspective of acoustic profile interpretations,the scale,range,and spatial locations of the microgeomorphology in the HRD revealed seasonal variation characteristics,and the spatial distributions displayed significant regional differentiation characteristics.In addition,strong stratigraphic disturbances and areas with densely distributed buried ancient channels reflected the activity and instability of the submarine shallow strata.Through the interpretation of the sub-bottom profile detection data,the diversion processes of the flow paths in the lower reaches of the Huanghe River were obtained for a certain historical period in the coastal waters of the HRD.This study further clarified the relationships between the micro-geomorphologic features and spatial combinations,which is important for research on micro-geomorphologic features and their dynamic mechanisms.展开更多
A transportation hub is the key link in the construction of the comprehensive three-dimensional transportation corridor of the Yangtze River Economic Belt,and is the basic factor responsible for the promotion of this ...A transportation hub is the key link in the construction of the comprehensive three-dimensional transportation corridor of the Yangtze River Economic Belt,and is the basic factor responsible for the promotion of this belt.A high-speed railway hub has the“last kilometer of time-space compression”effect and is the key to building an efficient,convenient,modern,and comprehensive transportation system.This study constructed a model for measuring the connection-distribution performance of the high-speed railway hub,determined the connection-distribution performance of the urban high-speed railway hub in the Yangtze River Economic Belt,and analyzed its spatial differentiation characteristics,further revealed the influencing mechanism of the connection-distribution performance of the high-speed railway hub.The main results are as follows:(1)The connection-distribution performance of the high-speed railway hub in the Yangtze River Economic Belt presented an“olive-shaped pattern”grade structure with two small ends and a large middle section,that is,the number of high-speed railway stations with high performance and average performance was small,and the number of high-speed railway stations with good performance and medium performance was large.(2)The connection-distribution performance of the high-speed railway hub in the Yangtze River Economic Belt showed a regional differentiation pattern of“high in the east and low in the west”and“high in the north and low in the south”,and showed an urban agglomeration differentiation pattern of“high in the core areas but low in the marginal areas”;moreover,spatial differences were prominent in the distribution of nine evaluation indexes of the connection-distribution performance of the high-speed railway hub.(3)GDP,urbanization rate,city level,station passenger flow and frequency of shuttle bus were key driving factors affecting the connection-distribution performance of the high-speed railway hub.At the same time,there were significant differences in the key driving factors for the connection-distribution performance grades of high-quality,good,medium and average.展开更多
Smart urban development is an inevitable choice, and is essential to overall strength improvement. It is important to explore an urban smart development path which unites smart growth with driving shrinkage perfectly ...Smart urban development is an inevitable choice, and is essential to overall strength improvement. It is important to explore an urban smart development path which unites smart growth with driving shrinkage perfectly in forming scientific and sustainable development concept and responding to new normal strategic opportunities. Based on statistic data of 294 prefecture-level cities and above in China from 2000 to 2015, we analyzed spatial and temporal evolution of urban smart development in China by constructing a dynamic fitting model of urban land expansion, population growth, and economic development as well as the coefficient of variation of urban smart development(CVSD). Further efforts were then made to consider differential distribution regularity of urban smart development so as to understand the driving mechanisms of heterogeneous classification of urban smart development in China from different scales and scale variation. Our results indicate that: 1) the disordered growth tendency of urban cities in China is overall well controlled in the middle, and late research and it mainly presented a doublet coexistence of shrinkage disordered cities and smart developing cities. It is particularly obvious that Northeast China and East China have regarded shrinkage disordered cities and smart developing cities as main development tendency separately. 2) Areas with basic stability and relative variation were relatively dispersed across the time period, but the proportion was far beyond areas with significant variation. It demonstrates a relative equilibrium spatial and temporal differential evolution pattern of prefecture-level cities and above in China, except for Tongling, Lanzhou and Chaoyang. 3) prefecture-level cities and above in China are mostly characterized by shrinkage disordered and smart development classification under the background of different scale and scale variation from 2000–2015; however, the spatial resonance relation is not obvious. 4) There are many interaction factors forming an important driving mechanism in developing the spatial and temporal pattern of urban smart development in China, including natural geographical factors, industrial structure adjustment, human capital radiation, regional traffic accessibility, and government decision-making intervention.展开更多
To investigate the spatial synergy between agricultural development level and transport superiority degree in grain-producing areas of the central Jilin Province and the driving mechanism between them,22 counties in t...To investigate the spatial synergy between agricultural development level and transport superiority degree in grain-producing areas of the central Jilin Province and the driving mechanism between them,22 counties in the central Jilin Province were used as the research units to calculate agricultural development level and transport superiority degree using the entropy weighting method,weighted travel time and raster cost distance.The spatial econometric model was used to analyze the mechanism of the mutual influence between the two.The main conclusions are as follows.1)Agricultural development level around Changchun,the provincial capital city,and in the areas of Changchun-Jilin and Changchun-Gongzhuling is high,whereas the development level of the counties in the southwest is low.2)Transport superiority degree of each county has improved,the overall connectivity of the road networks has been optimized,and the level of transportation accessibility has shown the development trend of‘centralization’,exhibiting the characteristics of proximity diffusion.3)Locally,there is spatial heterogeneity in the mutual driving effects of the two,with six main patterns.4)The theoretical conditions of von Thunen’s agricultural location have changed under the conditions of market economy due to the improvement of the transport networks,the new model of agricultural development,and the changes of the market system.展开更多
Interregional migration has broad and far-reaching impacts on regional urbanization process in ethnic minority areas of Southwest China.The previous literature of interregional migration paid less attention on the eth...Interregional migration has broad and far-reaching impacts on regional urbanization process in ethnic minority areas of Southwest China.The previous literature of interregional migration paid less attention on the ethnic minority areas with fragile geographical feature and marginal socio-economic context in the developing world due to the dearth of reliable data.Based on the 2015 national 1%population sampling survey at the village/community scale,taking Yulong Naxi Autonomous County,Yunnan Province,China as the case study,this paper analyzed the spatial differentiation pattern.The results showed that:(1)migration in Yulong Naxi Autonomous County exhibited obvious spatial differentiation characteristics in terms of population aggregation,population loss,migration direction,and migration activity;(2)the overall spatial differentiation of migration exhibited a"layer+sector"pattern in Yulong Naxi Autonomous County:the first layer was active areas with net inflows(<20 km from the seat of the county government),the second layer was inactive areas(within 20–60 km of the seat of the county government),and the third layer was a mixed"layer+sector"zone(>60 km to the seat of the county government),comprised of inactive areas and active areas with net outflows;(3)the spatial differentiation pattern of migration was highly correlated with the regional contexts including the regional economic development,regional transportation accessibility and regional social development,while regional physical geographical factors had insignificant relationships with the migration pattern.展开更多
The study and protection for traditional villages are very important for us to protect Chinese historical and cultural heritage. Data show that under the condition of rapid urbanization. The number and coverage of tra...The study and protection for traditional villages are very important for us to protect Chinese historical and cultural heritage. Data show that under the condition of rapid urbanization. The number and coverage of traditional villages in western China are decreasing. It is impossible to effectively protect a large number of rural settlements at the bottom of China’s traditional settlement system. Therefore, it is necessary to explore the spatial survival status of traditional villages and protect them comprehensively and extensively. Using the digital elevation model (DEM) data of traditional villages in Gansu Province, China, published by the Ministry of Housing and Urban Development and the attribute data obtained by the Statistics Bureau of Gansu Province, China, the nuclear density, the Mulan indices, the correlations between the heights and the centers are calculated and used to study the spatial different characteristics of the villages, and a number of results have been achieved: 1) In spatial differentiation, the spatial agglomeration of the villages is obvious and different, which can be seen by the distribution of the villages from along the upper reaches of the Yellow River to the southeast, and the distribution of prefecture-level cities is related to the landforms. 2) In vertical spatial distribution, the span of the altitude data is large. Among the villages, the Zagana Village in Diebu County of Gannan City is the highest and the Zhengjiashe Village in Bingkou Town of Longnan City is the lowest. With the increase of altitude, the number of traditional villages generally shows a tendency of decrease. 3) The spatial differentiation of the traditional villages has a clear normal distribution with the elevation, and the spatial differentiation is low, showing a distinct gourd-like structure;the eastern and southern regions are more concentrated, while the northern and western regions are less concentrated. 4) The spatial differences of the traditional villages have the characteristics of regional differences, which are weakly related to the distance between the central cities and occur mainly in the Longnan mountain regions, the Loess Plateau in the middle of Longzhong and the Gannan plateau. The results of this study are a useful support in protection of traditional villages in provincial scale. It helps to enhance the integrity and systematicness of the protection of the spatial distribution of traditionally villages. The Chinese government had put forward the “Poverty alleviation strategy” to help Gansu Province to get out of the villages’ trouble. Viewed from this angle, the research for effective patterns of traditional villages’ protection and exploitation plays a crucial role in the development of China’s “Poverty Alleviation Strategy”.展开更多
基金The authors acknowledge funding through the National Natural Science Foundation of China(NSFC Grants Nos.91850108 and 61675179)the National Key Research and Development Program of China(Grant No.2017YFA0205700)the Open Foundation of the State Key Laboratory of Modern Optical Instrumentation,and the Open Research Program of Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province.Z.R.,T.Z.,and J.H.are named inventors on a number of related patent applications related to this work。
文摘Phase is a fundamental resource for optical imaging but cannot be directly observed with intensity measurements.The existing methods to quantify a phase distribution rely on complex devices and structures and lead to difficulties of optical alignment and adjustment.We experimentally demonstrate a phase mining method based on the so-called adjustable spatial differentiation,by analyzing the polarization of light reflection from a single planar dielectric interface.Introducing an adjustable bias,we create a virtual light source to render the measured images with a shadow-cast effect.From the virtual shadowed images,we can further recover the phase distribution of a transparent object with the accuracy of 0.05λRMS.Without any dependence on wavelength or material dispersion,this method directly stems from the intrinsic properties of light and can be generally extended to a broad frequency range.
基金The Knowledge Innovation Project of CAS, No.KZCX2-310-01, No.KZCX2-307 National Natural Science Foundation of China, No. 40101010
文摘By using digitized land use maps of Beijing in 1982, 1992 and 1997 and employing GIS spatial analysis techniques, this paper conducts an empirical study on the spatial differentiation and spatial patterns of urban land use growth in Beijing in the period of 1982–1997. It is observed that urban land use growth in Beijing went beyond the control of urban planning, in terms of the extraordinary high growth rate and undesired spatial pattern. The rate of urban expansion after 1982, which was predominated by growth of industrial land, was extraordinary high compared to its historical period. While its growth centers have been actively shifting toward the northern part, rather than toward the southern and eastern parts as designated by the latest General Plan (1991–2010) of Beijing, its spatial pattern of urban land use growth in general was in distinct concentric sprawl, which seriously violated the General Plan of Beijing.
基金National Natural Science Foundation of China, No.41401164, No.41201128
文摘In this study, housing prices data for residential quarters from the period 2001-2012 were used and Global Differentiation Index （GDI） was established to measure the overall differentiation trend in housing prices in Yangzhou City, eastern China. Then the influence of the natural landscape and environment on prices of global housing market and housing submarkets was evaluated by the hedonic price model. The results are shown as follows. （1） There have been increasing gaps among housing prices since 2001. In this period, the differentiation trend has shown an upward fluctuation, which has been coupled with the annual growth rate of housing prices. （2） The spatial distribution of residential quarters of homogenous prices has changed from clustered in 2001 into dispersed in 2012. （3） Natural landscape and environmental externalities clearly influence spatial differentiation of housing prices. （4） In different housing submarkets, the influence of natural landscape and environmental eternalities are varied. Natural landscape characteristics have significant impact on housing prices of ordinary commercial houses and indemnificatory houses, while the impact of environmental characteristics have obvious influence on housing prices of cottages and villas.
基金National Natural Science Foundation of China, No.40701150 National Science and Technology Support Project, No.07H70163AR National Key Project of Scientific and Technical Supporting Programs,No.2006BAC08B03,No.2008BAC34B06
文摘GIMMS NDVI database and geo-statistics were used to depict the spatial distribution and temporal stability of NDVI on the Mongolian Plateau.The results demonstrated that:(1) Regions of interest with high NDVI indices were distributed primarily in forested mountainous regions of the east and the north,areas with low NDVI indices were primarily distributed in the Gobi desert regions of the west and the southwest,and areas with moderate NDVI values were mainly distributed in a middle steppe strap from northwest to southeast.(2) The maximum NDVI values maintained for the past 22 years showed little variation.The average NDVI variance coefficient for the 22-year period was 15.2%.(3) NDVI distribution and vegetation cover showed spatial autocorrelations on a global scale.NDVI patterns from the vegetation cover also demonstrated anisotropy;a higher positive spatial correlation was indicated in a NW-SE direction,which suggested that vegetation cover in a NW-SE direction maintained increased integrity,and vegetation assemblage was mainly distributed in the same specific direction.(4) The NDVI spatial distribution was mainly controlled by structural factors,88.7% of the total spatial variation was influenced by structural and 11.3% by random factors.And the global autocorrelation distance was 1178 km,and the average vegetation patch length(NW-SE) to width(NE-SW) ratio was approximately 2.4:1.0.
基金National Natural Science Foundation of ChinaNo.41371177
文摘The urban vulnerability poses a serious challenge to achieving sustainable devel- opment. With the concentration of the population and the economy, cities must manage the higher frequencies and risks of various hazards and are becoming more vulnerable. Re- search on the assessment and regulatory control of urban vulnerability is of great significance for both urbanization quality improvement and sustainable development in China or other countries in the world. Because of the complexity of cities and vulnerability concepts, existing studies have focused on different aspects of urban vulnerability. And the research content of urban vulnerability is scattered and relatively independent, leading to a lack of comparability among the research data and resulting in tremendous difficulties in summarizing the conclu- sions through comparison of independent research data. Therefore the goal of this study was to construct urban vulnerability index （UV/） from the perspective of sustainable development that could assess urban vulnerability comprehensively. In this study, we selected 10 subin- dexes involving 36 specific parameters from four aspects （resources, eco-environmental sys- tems, economics, and social development） to construct a comprehensive index system. We also established the standard values of measurements. Then we take 288 prefecture-level cities in China as a study area and evaluate its overall urban vulnerability and its spatial differentiation. Results indicate that urban vulnerability of China has a remarkable spatial differentiation of both ＂gradient distribution＂ and ＂clustered distribution＂; the extent of urban vulnerability corresponds to city size, the bigger the city, the lower its vulnerability; re- source-based cities are more vulnerable than comprehensive cities; a city＇s economic growth rate does not reflect the extent of its urban vulnerability. Further, we offer a few suggestions to cope with urban vulnerability in China.
基金National Natural Science Foundation of China,No.41601151Natural Science Foundation of Guangdong Province,No.2016A030310149Pearl River S&T Nova Program of Guangzhou
文摘This study analyzes the spatial patterns and driving forces of housing prices in China using a 2,872-county dataset of housing prices in 2014.Multiple theoretical perspec-tives on housing demand,supply,and market,are combined to establish a housing price model to explore the impact of land prices on housing prices.The relative impacts of land prices on housing prices at different administrative levels are then analyzed using the geo-graphical detector technique.Finally,the influencing mechanism of land prices on housing prices is discussed.The main conclusions are as follows.(1)Housing prices have a pyra-mid-ranked distribution in China,where higher housing prices are linked to smaller urban populations.(2)Land prices are the primary driver of housing prices,and their impacts on housing prices vary over different administrative levels.To be specific,the effect of land prices is the strongest in the urban districts of provincial capital cities.(3)The internal influ-ence mechanisms for land prices driving housing prices are:topographic factors,urban con-struction level,the agglomeration degree of high-quality public service resources,and the tertiary industrial development level.The urban land supply plan(supply policies)is the in-trinsic driver that determines land prices in cities;through supply and demand,cost,and market mechanisms,land prices then impact housing prices.
基金Under the auspices of the National Natural Science Foundation of China (No. 70373029)
文摘The policy of land transfer has greatly influenced the macro economy of China with the commencement of another innovation of land use system. Therefore, it is urgent to put forward some rational and feasible suggestions for local government to manage the market of land transfer. Moreover, it is important in the field of study on agricultural land use change to analyze the spatial differentiation and structural specification of land transfer, which are caused by rural households＇ behavior. This paper selected I l factors covering four aspects of rural households＇ family structure, family location, family income structure and the natural quality of land resources, all of which influence the behavior differentiation of rural households, to establish the index model indicating spatial differentiation of land transfer. Results show that the spatial differentiation of land transfer can be divided into four degrees and three categories through analyzing rural households＇ questionnaires from Shanghai, Nanjing and Taizhou in the Changjiang （Yangtze） River Delta. Since up to 80% of rural households belong to middle degrees, it can be concluded that the rural land market develops evenly in the study areas. And it is also indicated that the natural quality of land resources and the maximum income of rural land are most important factors influencing the spatial differentiation of land transaction. Considering different factors, the countermeasures can be carried out to enhance the spatial differentiation of land transfer so as to promote economic development and social security of rural China. All in all, both micro- factors and macro-factors influencing rural households＇ behavior of rural land transfer should be taken into account in order to make spatial differentiation and structural specification of rural land transfer notable.
基金the National Natural Science Foundation of China(No.41901205&41701127)he Natural Science Foundation of Jiangsu Province(No.BK20190482)+1 种基金the Philosophy and Social Science Research Project of Jiangsu University(No.2019SJA0034&2016SJD790012)the Scientific Research Start-up Project of Nanjing University of Science and Technology(No.AE89991/117)。
文摘The scientific analyses of the spatial patterns of regional eco-environment livability,along with the explorations of the correlations between ecoenvironments and population and economic activity distributions,are of major significance in the guidance of the coordinated development between social economies,natural resources,and environments.In this study,the topography,climate,hydrology,land cover,air quality,and the dangers presented by natural hazards in the study area were investigated in order to establish an evaluation model for the regional eco-environmental livability.Then,the observed spatial patterns and regional differences in the eco-environmental livability,as well as their relationships with the distributions of population and economic activities in Zhejiang Province,were investigated.The results showed that the ecoenvironmental livability in Zhejiang Province displayed a gradual decreasing trend from southwest to northeast,as well as from the mountains to the hills,valleys,and plains areas.During the compartmentalization of the eco-environmental livability,it was observed that the lowest livable area covered the largest population,accounting for approximately 29.64%of the total population in the study area.The higher livable areas covered the widest land areas,accounting for approximately 26.15%of the total area.Moreover,it was found that the eco-environmental livability in the mountain areas was higher than that in the plain areas in Zhejiang Province.Furthermore,the ecoenvironmental livability was found to have a significant exponential relationship with the population and GDP densities of Zhejiang Province,with the R^2 of the curve-fittings reaching 0.835 and 0.656,respectively.However,it was determined that the coefficient of the exponential function was negative,which indicated that a strong negative relationship existed between the eco-environmental livability and densities of the population and economic activities.It was assumed that the impacts of anthropogenic factors were the fundamental causes of this negative correlation.This study introduced two new factors(air quality and natural hazards)into the evaluation framework of eco-environmental livability.As a result,a more comprehensive model was established for the evaluation of eco-environmenta livability in certain segments of the study area Additionally,the correlation between ecoenvironment livability and human activities was discussed in-depth,which can potentially provide theoretical and practical guidance for the implementation of eco-livability in China,and possibly even those of other vast developing countries.
基金ssupported by the National Natural Sciences Foundation of China (90302009,40801216)the Ministry of Water Resources' Special Funds for Scientific Research on Public Causes (201001062)
文摘The spatial distribution of vegetation in Qaidam Basin was analyzed using GIMMS（Global Inventory Modeling and Mapping Studies） /NDVI（Normalized Difference Vegetation Index） data set from January 1982 to December 2006.Based on the data of precipitation,terrain,stream systems,land use and the map of vegetation distribution in Qaidam Basin,we studied the factors influencing the spatial distribution of vegetation.The results showed that the vegetation was generally low in Qaidam Basin and there was a clear semi-ring structure from southeast to northwest.In some areas,the existence of rivers,lakes and spring belts turned this semi-ring structure into a non-continuous state and formed distinct bright spots and continuous linear features.There were four main factors that affected the spatial distribution of vegetation coverage in Qaidam Basin,i.e.,precipitation,hydrological conditions,altitude and human activities.Precipitation and altitude have a correlation and determine the basic pattern of vegetation distribution in Qaidam Basin.The impacts of hydrological conditions and human activities were mainly embodied in partial areas,and often broke the pattern of vegetation distribution dominated by precipitation and altitude.
基金supported by the Science and Technology Service Network Fund Project in the Chinese Academy of Sciences (TSS-2015-014-FW1-2)National Natural Science Foundation of China (U1603242+2 种基金 41471173)West Light Foundation of the Chinese Academy of Sciences (2016-QNXZ-A4)Youth Innovation Promotion Association, Chinese Academy of Sciences (2014390)
文摘Stable isotope values of oxygen （180） and hydrogen （2H） of surface waters were used to study the origin and environmental significanees in the Issyk-Kul basin of Kyrgyzstan in Central Asia, which is the most important intermountain basin in the modern Tien Shan orogen. This study is the first analysis of hydrochemical spatial differentiation in the stable isotopes of surface waters in this watershed. 75 samples were collected from rivers, springs, lakes, rain and snow during the rainy season in July and August of 2o16. Stable isotopes of 180 and 2H were studied for all samples, and cation ratios （Sr/Ca and Mg/Ca） were also determined for lake water samples. Stable isotope values from precipitation scattered around the Local Meteoric Water Line （determined from Urumqi Station of the global network of isotopes in precipitation （GNIP））, together with values of the Deuterium excess parameter （d） from 15.3‰ to 30.5‰, with an average of 19.8‰, indicating that the moisture sources are primarily from regions with low relative humidity. The 8180 and 52H values were significantly different between the river and lake samples, indicating that regional evaporation caused the isotopic enrichment of lake water. Geospatial autocorrelation, measured by Moran＇s I coefficient, indicated weak spatial autocorrelation within stable isotopes of oxygen and hydrogen in the surface waters of the studied area, which is primarily an effect of climate during the water chemistry evolution. The cation ratios Sr/Ca and Mg/Ca in lake water samples were not correlated with the concentration of total dissolved solids, but did show correlation with stable isotopic values, which is significant for paleoenvironmental reconstruction.
基金supported by 2019 Guizhou Provincial Philosophy and Social Science Planning Project(19GZQN11)。
文摘The protection and development problems in ethnic minority villages have received great attention from the Chinese government.This study aims to systematically identify the spatial differentiation characteristics of ethnic minority villages and their influencing factors in Guizhou Province.Applying ArcGIS and GeoDa,a total of 1,014 ethnic minority villages in the four batches announced by the Ethnic and Religious Affairs Commission of Guizhou Province(272in the first batch,240 in the second batch,255 in the third batch,and 247 in the fourth batch)served as the research objects.Utilizing the economic development data in Guizhou Statistical Yearbook 2018-2020 for analysis,the coupling calculation of the spatial layout and economic development level of ethnic minority villages was conducted.The results indicate that the number of ethnic minority village points varies in spatial distribution with remarkable agglomeration.The spatial equilibrium distribution of ethnic minority villages in the province is imbalanced.The kernel density is characterized by independent single kernel centers with sporadic distributions of subcenters and an echelon distribution whole.The spatial complexity distribution indicates that ethnic minority villages in Guizhou possess unequal characteristics,and the fractal of the system structure is more complicated.The findings reveal that the spatial distribution of ethnic minority characteristic villages in Guizhou is highly consistent with that of ethnic minorities in Guizhou.The distribution is the combined results of geographical factors and socialeconomic factors.Most ethnic minority characteristic villages in Guizhou Province are located in areas with complex terrain,inconvenient transportation,and relatively backward economic development.Based on the current geospatial distribution of ethnic minority villages,the present study will provide remarkable implications for the Chinese government to implement the Rural Revitalization Strategy from several key aspects.The Chinese government should establish a protection and development mechanism in ethnic minority villages and strive to enhance the characteristics of ethnic cultural industries.Meanwhile,the"integration of culture and tourism"should be taken as the development strategy while the industry should support rural economic development and help eliminate poverty.This is of crucial practical significance to national unity and rural revitalization in China.
基金National Natural Science Foundation of China,No.41571113,No.41771134,No.41701126Strategic Priority Research Program of CAS:Evaluation of Connectivity of Infrastructure Network and Spatial Optimization
文摘Coal is a basic resource and its use guarantees the development of national economies and human society. Thus, coal transportation is an important part of China's overall transportation system. In this system, ports are the vital transit nodes. This study considered coastal ports in China and analysed the evolution of coal transportation from 1973 to 2013. We focused on the spatial pattern of coal loading and unloading, and summarized the main characteristics and development of the processes. Then, we examined the volumes of coal transported and regional changes in these amounts using mathematical models and indicators. Finally, we analysed the specialized function and spatial differentiation of the ports involved in coal transportation to reveal their spatial relationship and temporal evolution. We found that the spatial pattern of coal transportation changed from "south input and north output" to "all input and north output". However, the prominent ports used for coal unloading are still concentrated in areas south of the Yangtze River. Coal loading is concentrated on the west bank of Bohai Bay. In addition, some ports around Bohai Bay, such as Dandong, Dalian, Yantai, and Qingdao, changed from traditional coal loading ports to unloading ports. This study further developed the theory of transport geography, and improved our understanding of China's coal transportation system.
基金Under the auspices of the Second Comprehensive Scientific Investigation and Research Project of the Qinghai-Tibet Plateau(No.2019QZKK0406,2019QZKK1007)the National Natural Science Foundation of China(No.42001139,42101170)+1 种基金the Chinese Academy of Sciences Strategic Leading Science and Technology Project(No.XDA20010102)China Postdoctoral Science Foundation(No.2020M670472,2020M680660)。
文摘The Changtang Plateau(CTP)in Qinghai-Tibet Plateau of China is one of the top-10 uninhabited areas with the most important ecological value in the world.It is of great academic and practical significance to carry out research on human settlements in the marginal zones of the uninhabited areas to promote harmonious coexistence between humans and nature on the CTP.Using high-definition remote-sensing images to visually interpret and identify settlement-patch data,combined with field investigations,this study explores the spatial characteristics of human settlements in Shuanghu and Nyima counties and their responses to natural and socioeconomic conditions in the hinterland of the CTP.Findings reveal that the scale of human settlements on the CTP is extremely small,and density is very sparse.Settlements on the CTP primarily consist of several households,with some containing more than a dozen households,or are sub-village scale.Socioeconomic development is low and socioeconomic factors have a weak influence on the settlement layout on the CTP.Natural factors are the core elements affecting the layout of human settlements on the CTP.Settlements tend to occur on low mountains,gentle slopes,and areas with high average annual temperatures.Careful settlement site selection can help to mitigate the impact of natural disasters.To meet the needs of grazing,settlement layouts must typically have a high-quality grassland orientation.Riverbanks are key settlement areas,and settlement sites are often far away from alpine salt lakes.The characteristics of settlements on the CTP and their responses to environmental conditions significantly differ from those of human settlements in low-altitude inland areas.
基金Under the auspices of the Foundation of the Education Department of Jilin Province,China(No.JJKH20211290KJ)National Natural Science Foundation of China(No.42171198)。
文摘Village classification is the first step to implementing China’s rural revitalization(RR)strategy,and understanding the geographic differences in the distribution of village types helps to grasp the pathway of their unique development.This study spatialized9250 villages in Jilin Province(divided into six types)of China,and their distribution characteristics and influencing factors were examined using methods such as kernel density estimation,Ripley’s K function,the co-location quotient,and Geodetector.The results indicate that the spatial distribution balance and density of village types are different.All types of villages show an agglomeration distribution pattern,but the scale and intensity vary.There is a strong spatial association between agglomerative promotion(AP)and stable improvement(SIm)villages,as well as between characteristic protection(CP)and prospering frontier and enriching people(PE)villages.The factors affecting their distribution include terrain undulation,the percentage of arable land,the distance to the county town,road network density,population density,gross domestic product(GDP),and industrial enterprise density.The influencing factors for the distribution of village types are closely related to the function of each village.Based on the differences in the spatial distribution and influencing factors of different village types,policy suggestions are given for classified development.
基金Supported by the General Program of Natural Science Foundation of Shandong Province(No.ZR2020MD063)the Youth Program of Natural Science Foundation of Shandong Province(No.ZR2013DQ025)the National Natural Science Foundation of China and Shandong Province Joint Funds(No.U1706214)。
文摘Submarine micro-geomorphology is a geo-morphological type occurring in shallow and surface areas of seabed.The combined relationships and distribution of the micro-geomorphology indirectly reflect coupling relationships among the sediment deposition,dynamic environment,and geomorphologic evolution.Spatial differentiation and dynamic changes in micro-geomorphology were studied based on acoustic data interpretation from a wide range(3200 km^(2))of the Huanghe(Yellow)River delta(HRD).The combination of the sub-bottom profiler and the side-scan sonar methods allowed for the identification of submarine shallow micro-geomorphologic types,as well as their scale and spatial distributions.There were seven typical micro-geomorphologic features in the shallow and surface areas of the HRD,including buried ancient channels,stratigraphic disturbances,scour troughs,sand waves,pits,erosional remnants,and sand spots.The coupling and superposition of the sediment,sediment characteristics,seabed scouring and silting,and hydrodynamic conditions of the Huanghe River had combined effects on the patterns of micro-geomorphologic types,characteristics,and ranges.From the perspective of acoustic profile interpretations,the scale,range,and spatial locations of the microgeomorphology in the HRD revealed seasonal variation characteristics,and the spatial distributions displayed significant regional differentiation characteristics.In addition,strong stratigraphic disturbances and areas with densely distributed buried ancient channels reflected the activity and instability of the submarine shallow strata.Through the interpretation of the sub-bottom profile detection data,the diversion processes of the flow paths in the lower reaches of the Huanghe River were obtained for a certain historical period in the coastal waters of the HRD.This study further clarified the relationships between the micro-geomorphologic features and spatial combinations,which is important for research on micro-geomorphologic features and their dynamic mechanisms.
基金The Key Project of National Natural Science Foundation of China,No.41930644。
文摘A transportation hub is the key link in the construction of the comprehensive three-dimensional transportation corridor of the Yangtze River Economic Belt,and is the basic factor responsible for the promotion of this belt.A high-speed railway hub has the“last kilometer of time-space compression”effect and is the key to building an efficient,convenient,modern,and comprehensive transportation system.This study constructed a model for measuring the connection-distribution performance of the high-speed railway hub,determined the connection-distribution performance of the urban high-speed railway hub in the Yangtze River Economic Belt,and analyzed its spatial differentiation characteristics,further revealed the influencing mechanism of the connection-distribution performance of the high-speed railway hub.The main results are as follows:(1)The connection-distribution performance of the high-speed railway hub in the Yangtze River Economic Belt presented an“olive-shaped pattern”grade structure with two small ends and a large middle section,that is,the number of high-speed railway stations with high performance and average performance was small,and the number of high-speed railway stations with good performance and medium performance was large.(2)The connection-distribution performance of the high-speed railway hub in the Yangtze River Economic Belt showed a regional differentiation pattern of“high in the east and low in the west”and“high in the north and low in the south”,and showed an urban agglomeration differentiation pattern of“high in the core areas but low in the marginal areas”;moreover,spatial differences were prominent in the distribution of nine evaluation indexes of the connection-distribution performance of the high-speed railway hub.(3)GDP,urbanization rate,city level,station passenger flow and frequency of shuttle bus were key driving factors affecting the connection-distribution performance of the high-speed railway hub.At the same time,there were significant differences in the key driving factors for the connection-distribution performance grades of high-quality,good,medium and average.
基金Under the auspices of National Natural Science Foundation of China(No.41101548)Philosophy and Social Science Research Program of Heilongjiang Province in 2016(No.16JBL01)+1 种基金Key Research Projects of Economic and Social Development in Heilongjiang Province(No.JD2016014)Human Civilization and Social Science Supportive Program for Excellent Young Scholars of Harbin Normal University(No.SYQ2014-06)
文摘Smart urban development is an inevitable choice, and is essential to overall strength improvement. It is important to explore an urban smart development path which unites smart growth with driving shrinkage perfectly in forming scientific and sustainable development concept and responding to new normal strategic opportunities. Based on statistic data of 294 prefecture-level cities and above in China from 2000 to 2015, we analyzed spatial and temporal evolution of urban smart development in China by constructing a dynamic fitting model of urban land expansion, population growth, and economic development as well as the coefficient of variation of urban smart development(CVSD). Further efforts were then made to consider differential distribution regularity of urban smart development so as to understand the driving mechanisms of heterogeneous classification of urban smart development in China from different scales and scale variation. Our results indicate that: 1) the disordered growth tendency of urban cities in China is overall well controlled in the middle, and late research and it mainly presented a doublet coexistence of shrinkage disordered cities and smart developing cities. It is particularly obvious that Northeast China and East China have regarded shrinkage disordered cities and smart developing cities as main development tendency separately. 2) Areas with basic stability and relative variation were relatively dispersed across the time period, but the proportion was far beyond areas with significant variation. It demonstrates a relative equilibrium spatial and temporal differential evolution pattern of prefecture-level cities and above in China, except for Tongling, Lanzhou and Chaoyang. 3) prefecture-level cities and above in China are mostly characterized by shrinkage disordered and smart development classification under the background of different scale and scale variation from 2000–2015; however, the spatial resonance relation is not obvious. 4) There are many interaction factors forming an important driving mechanism in developing the spatial and temporal pattern of urban smart development in China, including natural geographical factors, industrial structure adjustment, human capital radiation, regional traffic accessibility, and government decision-making intervention.
基金Under the auspices of Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA19040500)。
文摘To investigate the spatial synergy between agricultural development level and transport superiority degree in grain-producing areas of the central Jilin Province and the driving mechanism between them,22 counties in the central Jilin Province were used as the research units to calculate agricultural development level and transport superiority degree using the entropy weighting method,weighted travel time and raster cost distance.The spatial econometric model was used to analyze the mechanism of the mutual influence between the two.The main conclusions are as follows.1)Agricultural development level around Changchun,the provincial capital city,and in the areas of Changchun-Jilin and Changchun-Gongzhuling is high,whereas the development level of the counties in the southwest is low.2)Transport superiority degree of each county has improved,the overall connectivity of the road networks has been optimized,and the level of transportation accessibility has shown the development trend of‘centralization’,exhibiting the characteristics of proximity diffusion.3)Locally,there is spatial heterogeneity in the mutual driving effects of the two,with six main patterns.4)The theoretical conditions of von Thunen’s agricultural location have changed under the conditions of market economy due to the improvement of the transport networks,the new model of agricultural development,and the changes of the market system.
基金This work was supported by the National Natural Science Foundation of China(41930644).
文摘Interregional migration has broad and far-reaching impacts on regional urbanization process in ethnic minority areas of Southwest China.The previous literature of interregional migration paid less attention on the ethnic minority areas with fragile geographical feature and marginal socio-economic context in the developing world due to the dearth of reliable data.Based on the 2015 national 1%population sampling survey at the village/community scale,taking Yulong Naxi Autonomous County,Yunnan Province,China as the case study,this paper analyzed the spatial differentiation pattern.The results showed that:(1)migration in Yulong Naxi Autonomous County exhibited obvious spatial differentiation characteristics in terms of population aggregation,population loss,migration direction,and migration activity;(2)the overall spatial differentiation of migration exhibited a"layer+sector"pattern in Yulong Naxi Autonomous County:the first layer was active areas with net inflows(<20 km from the seat of the county government),the second layer was inactive areas(within 20–60 km of the seat of the county government),and the third layer was a mixed"layer+sector"zone(>60 km to the seat of the county government),comprised of inactive areas and active areas with net outflows;(3)the spatial differentiation pattern of migration was highly correlated with the regional contexts including the regional economic development,regional transportation accessibility and regional social development,while regional physical geographical factors had insignificant relationships with the migration pattern.
文摘The study and protection for traditional villages are very important for us to protect Chinese historical and cultural heritage. Data show that under the condition of rapid urbanization. The number and coverage of traditional villages in western China are decreasing. It is impossible to effectively protect a large number of rural settlements at the bottom of China’s traditional settlement system. Therefore, it is necessary to explore the spatial survival status of traditional villages and protect them comprehensively and extensively. Using the digital elevation model (DEM) data of traditional villages in Gansu Province, China, published by the Ministry of Housing and Urban Development and the attribute data obtained by the Statistics Bureau of Gansu Province, China, the nuclear density, the Mulan indices, the correlations between the heights and the centers are calculated and used to study the spatial different characteristics of the villages, and a number of results have been achieved: 1) In spatial differentiation, the spatial agglomeration of the villages is obvious and different, which can be seen by the distribution of the villages from along the upper reaches of the Yellow River to the southeast, and the distribution of prefecture-level cities is related to the landforms. 2) In vertical spatial distribution, the span of the altitude data is large. Among the villages, the Zagana Village in Diebu County of Gannan City is the highest and the Zhengjiashe Village in Bingkou Town of Longnan City is the lowest. With the increase of altitude, the number of traditional villages generally shows a tendency of decrease. 3) The spatial differentiation of the traditional villages has a clear normal distribution with the elevation, and the spatial differentiation is low, showing a distinct gourd-like structure;the eastern and southern regions are more concentrated, while the northern and western regions are less concentrated. 4) The spatial differences of the traditional villages have the characteristics of regional differences, which are weakly related to the distance between the central cities and occur mainly in the Longnan mountain regions, the Loess Plateau in the middle of Longzhong and the Gannan plateau. The results of this study are a useful support in protection of traditional villages in provincial scale. It helps to enhance the integrity and systematicness of the protection of the spatial distribution of traditionally villages. The Chinese government had put forward the “Poverty alleviation strategy” to help Gansu Province to get out of the villages’ trouble. Viewed from this angle, the research for effective patterns of traditional villages’ protection and exploitation plays a crucial role in the development of China’s “Poverty Alleviation Strategy”.
