Spatial pattern and drivers of urbanization in China's mid-level developing urban agglomeration:A case study of Chang-Zhu-Tan

Urban agglomeration has become the main form of regional spatial organization in China.While most of the existing studies of urban agglomeration in China have focused on the eastern coastal areas,urban agglomeration with mid-level development in the rest of the country has been overlooke1.To better understand the urbanization process of the mid-level developing urban agglomeration,this study investigated the clustering pattern and the drivers of both urban population and firm dynamics during 2005-2015 in the Changsha-Zhuzhou-Xiangtan(Chang-Zhu-Tan)urban agglomeration of China using the methods ofkernel density estimation and geographic detection.Our results show that centralization was obvious,although decentralization also occurred in Chang-Zhu-Tan,and that the spatial agglomeration was promoted by several factors,such as administrative resources,location advantage,labor cost,and consumption capacity.Some problems hindering the development of this region were also discovered:administrative resources played a critical role in urbanization because small towns and villages did not receive enough attention,and the effect of local policy was not as beneficial as expected.These findings partly explain the relatively slow development of mid-level developing urban agglomerations and have important implications for promoting healthier urbanization.

Spatial heterogeneity and driving mechanism of urban climbing and its impact on regional environment in varied landform types in the middle reaches of the Yellow River

Urbanization research is essential for the sustainable use of regional land resources and ecological environment protection.The expansion process and driving factors of urban construction land at different scales in the middle reaches of the Yellow River(MRYR)have not been comprehensively elucidated.In this study,we explored the distribution pattern of urban construction land on different slope gradients at different scales and analyzed its influencing factors.The main findings were as follows:(1)There has been significant expansion of urban construction land in the MRYR over the past 20 years.Spatial heterogeneity was observed in the regional urban construction land expansion process among different geomorphic regions.(2)The urban construction land in the MRYR was expanded vertically to areas with slopes of>5°,particularly in 2005–2010.Significant slope climbing of urban construction land was observed in the loess hilly-gully and rocky mountain areas.(3)In MRYR,68.45%of the counties were categorized as the slope-climbing types,including 37.38%high-slope-climbing types.(4)The regional population density and economic development level were closely associated with regional urban construction land area variability.(5)The climbing process of regional urban construction can effectively alleviate farmland encroachment and pressure on the regional ecological environment.The urban expansion of the metropolitan distribution areas in the Plain region(such as Xi'an,Taiyuan)had a relatively significant impact on the local carbon storage.

A Study on Vertical Spatial Transfer of Cultivated Land in Yunnan Province from 1986 to 2008

Based upon ArCGIS,the vertical spatial transfer law of cultivated land in Yunnan was studied through referring to three periods of remote sensing data of Land-Use and Land-Cover Change（LUCC） in Yunnan in 1986,1995 and 2000,Digital Elevation Model（DEM） of Yunnan Province and LUCC data in Yunnan from 2000 to 2008.The main factors that promote vertical spatial transfer law of cultivated land were analyzed by using SPSS,and the influence of policies and government acts upon the change of cultivated land was clarified.The findings indicated that for Yunnan cultivated land there is a trend that in the vertical direction steep slope areas and gentle slope areas divert into mid-slope areas.The primary factor influencing the vertical spatial transfer of cultivated land was policies and government acts.Also,the gradient of ground,total population and number of agriculture employed persons were also main factors in influencing the change of cultivated land,whose influence was obviously below policies and government acts.

Spatial patterns and driving forces of land use change in China during the early 21st century

Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science （LCS） in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21 st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the ＂Grain for Green＂ policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of ＂Western Development＂, ＂Revitalization of Northeast＂, coupled with rapidly economic development during this period.

The evolution of tea spatial agglomeration in China:An analysis based on different geographical scales

The spatial agglomeration of agricultural production is conducive to reducing planting costs, increasing production efficiency and improving product quality. It is an important way to promote the transformation and upgrad of tea industry and realize the modernization of China's tea industry. This study used Gini coefficient and spatial autocorrelation analysis to explore the characteristics of tea spatial agglomeration in China from three geographical scales: regional level, provincial level and prefecture level from the year 2005 to 2015. The results indicated that there was a significant scale effect on the tea spatial agglomeration. The agglomeration degree increased from the regional level, provincial level to prefecture level. The types of spatial agglomeration evolution of the three scales were Ushaped, continuous diffusion, and continuous agglomeration. The spatial autocorrelation of tea production could only be found at the prefecture level. Meanwhile, at the prefecture scale, we could not only reveal the pattern changes at the regional and provincial levels, but also identify tea production agglomeration regions. Compared with the large scale, the small scale could reveal the characteristics of tea spatial agglomeration in more details. Factors such as natural resource endowments, cost factor, technological advancement, agglomeration economy, and agricultural policy influenced the evolution of tea spatial agglomeration from different geographical scales. Finally, from the perspectives of spatial transfer of tea production, promoting spatial agglomeration, building tea production bases, and breaking administrative boundaries, we proposed several policy suggestions for optimizing the spatial layout of tea production.

STUDY ON THE SPATIAL PATTERNS OF LAND-USE CHANGE AND ANALYSES OF DRIVING FORCES IN NORTHEASTERN CHINA DURING 1990-2000

Land-use change is an important aspect of global environment change. It is,in a sense, the direct result of human activities influencing our physical environment. Supported bythe dynamic serving system of national resources, including both the environment database and GIStechnology, this paper analyzed the land-use change in northeastern China in the past ten years(1990 ― 2000). It divides northeastern China into five land-use zones based on the dynamic degree(DD) of land-use: woodland/grassland ― arable land conversion zone, dry land ― paddy fieldconversion zone, urban expansion zone, interlocked zone of farming and pasturing, and reclamationand abandoned zone. In the past ten years, land-use change of northeastern China can be generalizedas follows: increase of cropland area was obvious, paddy field and dry land increased by 74. 9 and276. 0 thousand ha respectively; urban area expanded rapidly, area of town and rural residenceincreased by 76. 8 thousand ha; area of forest and grassland decreased sharply with the amount of1399. 0 and 1521. 3 thousand ha respectively; area of water body and unused land increased by 148. 4and 513. 9 thousand ha respectively. Besides a comprehensive analysis of the spatial patterns ofland use, this paper also discusses the driving forces in each land-use dynamic zones. The studyshows that some key biophysical factors affect conspicuously the conversion of different land-usetypes. In this paper, the relationships between land-use conversion and DEM, accumulated temperature(≥10℃) and precipitation were analysed and represented. We conclude that the land-use changes innortheast China resulted from the change of macro social and economic factors and local physicalelements. Rapid population growth and management changes, in some sense, can explain the shaping ofwoodland/grassland ― cropland conversion zone. The conversion from dry land to paddy field in thedry land ― paddy field conversion zone, apart from the physical elements change promoting theexpansion of paddy field, results from two reasons: one is that the implementation of market-economyin China has given fanners the right to decide what they plant and how they plant their crops, theother factor is originated partially from the change of dietary habit with the social and economicdevelopment. The conversion from paddy field to dry land is caused primarily by the shortfall ofirrigation water, which in turn is caused by poor water allocation managed by local governments. Theshaping of the reclamation and abandoned zone is partially due to the lack of environmentprotection consciousness among pioneer settlers. The reason for the conversion from grassland tocropland is the relatively higher profits of farming than that of pasturing in the interlocked zoneof farming and pasturing. In northeastern China, the rapid expansion of built-up areas results fromtwo factors: the first is its small number of towns; the second comes from the huge potential forexpansion of existing towns and cities. It is noticeable that urban expansion in the northeasternChina is characterized by gentle topographic relief and low population density. Physiognomy,transportation and economy exert great influences on the urban expansion.

Temporal and spatial distribution of phytoplankton functional groups and role of environment factors in a deep subtropical reservoir

Phytoplankton and environment factors were investigated in 2015 and phytoplankton functional groups were used to understand their temporal and spatial distribution and their driving factors in Wanfeng Reservoir. Seventeen functional groups(B, D, E, F, G, J, Lo, MP, P, S1, T, W1, W2, X1, X2, Xph, Y) were identified based on 34 species. The dominant groups were: J/B/P/D in dry season, X1/J/Xph/G/T in normal season and J in flood season. Phytoplankton abundance ranged from 5.33×10~4 cells/L to 3.65×10~7 cells/L, with the highest value occurring in flood season and lowest in dry season. The vertical profi le of dominant groups showed little differentiation except for P, which dominated surface layers over 20 m as a result of mixing water masses and higher transparency during dry season. However, the surface waters presented higher values of phytoplankton abundance than other layers, possibly because of greater irradiance. The significant explaining variables and their ability to describe the spatial distribution of the phytoplankton community in RDA diff ered seasonally as follows: dry season, NH4-N, NO_3-N, NO_2-N, TN:TP ratio and transparency(SD); normal season, temperature(WT), water depth, TN, NH4-N and NO_3-N; flood season, WT, water depth, NO_3-N and NO_2-N. Furthermore, nitrogen, water temperature, SD and water depth were significant variables explaining the variance of phytoplankton communities when datasets included all samples. The results indicated that water physical conditions and hydrology were important in phytoplankton community dynamics, and nitrogen was more important than phosphorus in modifying phytoplankton communities. Seasonal differences in the relationship between the environment and phytoplankton community should be considered in water quality management.

Spatial and Temporal Pattern of Urban Smart Development in China and Its Driving Mechanism

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.

Spatial Scale Effects of Water Erosion Dynamics:Complexities, Variabilities, and Uncertainties

Severe water erosion is notorious for its harmful effects on land-water resources as well as local societies. The scale effects of water erosion, however, greatly exacerbate the difficulties of accurate erosion evaluation and hazard control in the real world. Analyzing the related scale issues is thus urgent for a better understanding of erosion variations as well as reducing such erosion. In this review article, water erosion dynamics across three spatial scales including plot, watershed, and regional scales were selected and discussed. For the study purposes and objectives, the advantages and disadvantages of these scales all demonstrate clear spatial-scale dependence. Plot scale studies are primarily focused on abundant data collection and mechanism discrimination of erosion generation, while watershed scale studies provide valuable information for watershed management and hazard control as well as the development of quantitatively distributed models. Regional studies concentrate more on large-scale erosion assessment, and serve policymakers and stakeholders in achieving the basis for regulatory policy for comprehensive land uses. The results of this study show that the driving forces and mechanisms of water erosion variations among the scales are quite different. As a result, several major aspects contributing to variations in water erosion across the scales are stressed: differences in the methodologies across various scales, different sink-source roles on water erosion processes, and diverse climatic zones and morphological regions. This variability becomes more complex in the context of accelerated global change. The changing climatic factors and earth surface features are considered the fourth key reason responsible for the increased variability of water erosion across spatial scales.

Spatial Patterns of LULC and Driving Forces in the Transnational Area of Tumen River:A Comparative Analysis of the Sub-regions of China,the DPRK,and Russia

Understanding the spatial patterns of land-use and land-cover(LULC)and their driving forces in transnational areas is important for the sustainable development of these regions.However,the spatial patterns of LULC and their driving forces across multiple scales are poorly understood in transnational areas.In this study,we analyzed the spatial patterns of LULC and driving forces in the transnational area of Tumen River(TATR)in 2016 across two scales:the entire region and the sub-regions of China,the Democratic People’s Republic of Korea(DPRK),and Russia.Results showed that the LULC was dominated by broadleaf forest and dry farmland in the TATR in 2016,which accounted for 66.86%and 13.60%of the entire region,respectively.Meanwhile,the LULC in the three sub-regions exhibited noticeable differences.In the Chinese and the DPRK’s sub-regions,the area of broadleaf forest was greater than those for the other LULC types,while the Russian sub-region was dominated by broadleaf forest and grassland.The spatial patterns of LULC were mainly influenced by topography,climate,soil properties,and human activities.In addition,the driving forces of the spatial patterns of LULC in the TATR had an obvious scaling effect.Therefore,we suggest that effective policies and regulations with cooperation among China,the DPRK,and Russia are needed to plan the spatial patterns of LULC and improve the sustainable development of the TATR.

Spatial-temporal Patterns and Driving Forces of Water Retention Service in China

Overwhelming water-deficiency conditions and an unbalanced water supply and demand have been major concerns of both the Chinese government and the general public during recent decades. Studying the spatial-temporal patterns and impact factors that influence water retention in China is important to enhance the management of water resources in China and other similar countries. We employed a revised Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST) model and regression analyses to investigate the water retention service in China. The results showed that the southeastern China generally performed much better than Northwest China in terms of the spatial distribution of water retention. In general, the efficacy of the water retention service in China increased from 2000 to 2014; although some areas still had a downward trend. Water retention service increased significantly(P < 0.05) in aggregate in the Qinghai-Tibet Plateau, and the Da Hinggan Mountains and Xiao Hinggan Mountains. However, the service in southwestern China showed a decreasing trend(P < 0.05), which would have significant negative impact on the downstream population. This study also showed that in China the changes in water retention service were primarily due to climate change(which could explain 83.49% of the total variance), with anthropogenic impact as a secondary influence(likewise the ecological programs and socioeconomic development could explain 9.47% and 1.06%, respectively). Moreover, the identification of water retention importance indicated that important areas conservation and selection based on downstream beneficiaries is vital for optimization protection of ecosystem services, and has practical significance for natural resources and ecosystem management.

A New Method Based on Association Rules Mining and Geo-filter for Mining Spatial Association Knowledge

Association rule mining methods, as a set of important data mining tools, could be used for mining spatial association rules of spatial data. However, applications of these methods are limited for mining results containing large number of redundant rules. In this paper, a new method named Geo-Filtered Association Rules Mining(GFARM) is proposed to effectively eliminate the redundant rules. An application of GFARM is performed as a case study in which association rules are discovered between building land distribution and potential driving factors in Wuhan, China from 1995 to 2015. Ten sets of regular sampling grids with different sizes are used for detecting the influence of multi-scales on GFARM. Results show that the proposed method can filter 50%–70% of redundant rules. GFARM is also successful in discovering spatial association pattern between building land distribution and driving factors.

Research on Spatial-Temporal Characteristics and Driving Factor of Agricultural Carbon Emissions in China

Macroscopic grasp of agricultural carbon emissions status, spatial-temporal characteristics as well as driving factors are the basic premise in further research on China’s agricultural carbon emissions. Based on 23 kinds of major carbon emission sources including agricultural materials inputs, paddy ifeld, soil and livestock breeding, this paper ifrstly calculated agricultural carbon emissions from 1995 to 2010, as well as 31 provinces and cities in 2010 in China. We then made a decomposed analysis to the driving factors of carbon emissions with logarithmic mean Divisia index （LMDI） model. The results show：（1） The amount of agricultural carbon emissions is 291.1691 million t in 2010. Compared with 249.5239 million t in 1995, it increased by 16.69%, in which, agricultural materials inputs, paddy ifeld, soil, enteric fermentation, and manure management accounted for 33.59, 22.03, 7.46, 17.53 and 19.39%of total agricultural carbon emissions, respectively. Although the amount exist ups and downs, it shows an overall trend of cyclical rise; （2） There is an obvious difference among regions：the amount of agricultural carbon emissions from top ten zones account for 56.68%, while 9.84%from last 10 zones. The traditional agricultural provinces, especially the major crop production areas are the main source regions. Based on the differences of carbon emission rations, 31 provinces and cities are divided into ifve types, namely agricultural materials dominant type, paddy ifeld dominant type, enteric fermentation dominant type, composite factors dominant type and balanced type. The agricultural carbon emissions intensity in west of China is the highest, followed by the central region, and the east zone is the lowest; （3） Compared with 1995, efifciency, labor and structure factors cut down carbon emissions by 65.78, 27.51 and 3.19%, respectively;while economy factor increase carbon emissions by 113.16%.

Detection of Multi-dimensional Driving Forces of Public Environmental Concern in China:Based on Spatial Heterogeneity Perspectives

Public environmental concern(PEC)is an important bottom-up force in building an environmentally sustainable society.Guided by attitude theory,this paper innovatively constructed a PEC evaluation index system,while introducing entropy weighted-TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)to realize the assessment of PEC.Exploratory spatial data analysis was used to portray the spatio-temporal evolution patterns of PEC in 362 Chinese cities at prefecture-level and above from 2011 to 2018.Furthermore,the Geodetector model was performed to identify the multi-dimensional determinants of PEC from the perspective of spatial heterogeneity.The results indicated that:1)PEC in China exhibited a fluctuating upward trend,consistent with the spatial distribution law of‘Heihe-Tengchong Line’and‘Bole-Taipei Line’;2)the driving effect of each factor varied dynamically,but in general,economic development level,population size,industrial wastewater,and education level were the dominant driving factors explaining the spatial variation of PEC;3)risk detection revealed that four factors,government environmental regulations,PM_(2.5),vegetation coverage,and natural resource endowment,had nonlinear effects on PEC;4)the interactions between factors all demonstrated an enhancement in explaining the spatial differentiation of PEC.PEC was driven by the comprehensive interaction of four-dimensional factors of economy,society,pollutant emissions,and ecology.Among them,population agglomeration accompanied by a high level of regional economy and information technology can explain the increase in PEC to the greatest extent.

Characteristics and Driving Forces of Spatial Expansion of Oasis Cities and Towns in Hexi Corridor, Gansu Province, China

This paper presents an integrated study of urban spatial expansion in the Hexi Corridor, Gansu Province, China based on TM, ETM remote sensing data in 1987, 1990, 1995, 2000, 2006 and 2011. The study explores the characteristics of urban spatial expansion and dynamic mechanism by using expansion speed index, expansion intensity index, compact index, fractal dimension, and extended flexibility index. We built the index system of influencing factors of urban spatial expansion by using the grey incidence model. The results showed that urban spatial expansion rate in the Hexi Corridor has been on the upward trend since 1987. Expansion intensity showed an obvious upward trend, however, the upward trend varied in different urban areas. In addition, the urban structure was loose relatively, but the urban compactness was more obvious. The urban spatial form tended to be simple, and the urban land use tended to become more intensive. Urban spatial expansion experienced several stages: padding internally, external expansion and padding internally. The main driving factors of urban spatial expansion are not the urban water resources and the oasis scale, but one or several factors such as economy, traffic, population, resource and national policy.

Spatial variability and driving factors of soil multifunctionality in drylands of China

Drylands are highly vulnerable to climate change and human activities.The drylands of China account for approximately 10.8%of global drylands,and China is the country most severely affected by aridity in Asia.Therefore,studying the spatial variation characteristics in soil multifunctionality(SMF)and investigating the driving factors are critical for elucidating and managing the functions of dryland ecosystems in China.Based on the environmental factors(mean annual precipitation(MAP),mean annual temperature(MAT),solar radiation(Srad),soil acidity(pH),enhanced vegetation index(EVI),and cation exchange capacity(CEC))and aridity from the“dataset of soil properties for land surface modeling over China”,we used non-linear regression,ordinary least square(OLS)regression,structural equation model(SEM),and other analytical methods to investigate the relationships of SMF with environmental factors across different aridity levels in China.SMF in different dryland regions varied significantly and showed a patchy distribution,with SMF index values ranging from–1.21 to 2.42.Regions with SMF index values from–0.20 to 0.51 accounting for 63.0%of dryland area in China.OLS regression results revealed that environmental factors like MAP,MAT,Srad,pH,EVI,and CEC were significantly related to SMF(P<0.05).MAP and MAT were correlated to SMF at the whole aridity level(P<0.05).SEM results showed that the driving factors of SMF differed depending on the aridity level.Soil pH was the strongest driving factor of SMF when the aridity was less than 0.80(P<0.001).Both soil CEC and EVI had a positive effect on SMF when aridity was greater than 0.80(P<0.01),with soil CEC being the strongest driving factor.The importance ranking revealed that the relative importance contribution of soil pH to SMF was greatest when aridity was less than 0.80(66.9%).When aridity was set to greater than 0.80,the relative importance contributions of CEC and EVI to SMF increased(45.1%and 31.9%,respectively).Our findings indicated that SMF had high spatial heterogeneity in drylands of China.The aridity threshold controlled the impact of environmental factors on SMF.

Spatial-temporal Dynamics and Driving Forces of Land Development Intensity in the Western China from 2000 to 2015

The change in land development intensity is an important perspective to reflect the variation in regional social and economic development and spatial differentiation.In this paper,spatial statistical analysis,Ordinary Least Squares(OLS),and Geographically weighted regression(GWR)methods are used to systematically analyse the spatial-temporal characteristics and driving forces of land development intensity for 131 spatial units in the western China from 2000 to 2015.The findings of the study are as follows:1)The land development intensity in the western China has been increasing rapidly.From 2000 to 2015,land development intensity increased by 3.4 times on average.2)The hotspot areas have shifted from central Inner Mongolia,northern Shaanxi and the Beibu Gulf of Guangxi to the Guanzhong Plain and the Chengdu-Chongqing urban agglomeration.The areas of cold spots were mainly concentrated in the Qinghai-Tibet Plateau,Yunnan,and Xinjiang.3)Investment intensity and the natural environment have always been the main drivers of land development intensity in the western China.Investment played a powerful role in promoting land development intensity,while the natural and ecological environment distinctly constrained such development.The effect of the economic factors on land development intensity in the western China has changed,which is reflected in the driving factor of construction land development shifting from economic growth in 2000 to economic structure,especially industrial structure,in 2015.

Analysis of stress and natural frequencies of high-speed spatial parallel mechanism

In order to grasp the dynamic behaviors of 4-UPS-UPU high-speed spatial parallel mechanism, the stress of driving limbs and natural frequencies of parallel mechanism were investigated. Based on flexible multi-body dynamics theory, the dynamics model of 4-UPS-UPU high-speed spatial parallel mechanism without considering geometric nonlinearity was derived. The stress of driving limbs and natural frequencies of 4-UPS-UPU parallel mechanism with specific parameters were analyzed. The relationship between the basic parameters of parallel mechanism and its dynamic behaviors, such as stress of driving limbs and natural frequencies of parallel mechanism, were discussed. The numerical simulation results show that the stress and natural frequencies are relatively sensitive to the section parameters of driving limbs, the characteristic parameters of material on driving limbs, and the mass of moving platform. The researches can provide important theoretical base of the analysis of dynamic behaviors and optimal design for high-speed spatial parallel mechanism.

Temporal-spatial change and driving mechanism for regional difference of domestic tourism in China

By using the variation coefficient,Gini coefficient and Theil coefficient,this paper makes preliminary exploration of temporalspatial change features and driving mechanism for regional differences of domestic tourism in China from 1995 to 2009.According to the results,we drew the following conclusions:(1)The regional difference of domestic tourism in China tends to be narrowing generally,and is less than that of inbound tourism,playing an important role in narrowing the overall gap of regional tourism in China.(2)The regional internal difference features:inter-provincial difference in the eastern region and difference among the eastern,central and western regions are comparatively obvious and demonstrate a significantly shrinking tendency,the change tendency is consistent with the change tendency of overall difference and exercises a decisive role in overall difference,whereas the inter-provincial difference in the central and western regions is small and relatively stable,having less influence on the overall difference.(3)The temporal-spatial change in regional difference is featured by:low-level provinces occupy a majority and are concentrated in the central and western regions,showing a tendency of narrowing difference;high-level provinces are concentrated in the eastern region,showing a tendency of spreading to the central and western regions;spatial pattern of regional difference demonstrates 4 types,i.e."proliferation type","polarization type","quiescence type"and"collapse type."(4)The driving force for regional difference of domestic tourism in China comes down to 3 aspects:regional socio-economic attribute,regional transport accessibility level and regional development policy.

Role of mountains and rivers in the formation of logistics enterprises'spatial pattern in the central urban areas of Chongqing

The complex landforms of a Shan-shui City(Shan-shui refers to mountains and rivers)significantly impact the selection of locations for logistics enterprises.This paper takes Chongqing,one of the most typical Shan-shui Cities in China,as the research object,and adopts spatial analysis methods and a mediating effect model,to explore the role of mountains and rivers in the formation of logistics enterprises’spatial pattern on the street scale.The study results reveal that 90% of the logistics enterprises in the central urban areas of Chongqing are located in the low-altitude area below 353m above sea level,and distributed in a north-south direction along the mountains,as a result of blockage by mountain ranges,such as those of Zhongliang Mountain and Tongluo Mountain.More than 70% of the logistics enterprises are located less than 5 km from either the Yangtze River or Jialing River,spreading along the rivers.In addition,more than half of the logistics enterprises in commercial and financial,and residential land are located within the urban core area,while 80.83% of the logistics enterprises located in warehousing land and industrial land are concentrated in the urban expansion area.In areas with high land prices,the negative effect of altitude on logistics enterprise agglomeration is weakened,while the promotion effect of river proximity on logistics enterprise agglomeration is enhanced.In the urban core area with the advantage of low altitude and proximity to the Jialing and Yangtze Rivers,the role of mountains and rivers on logistics enterprises is not apparent;in contrast,in the urban expansion area with more complex landforms,land price can be an effective means for the government to macro-manage the spatial pattern of logistics enterprises in a Shan-shui City.