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
Carbon cycle is one of the focuses of climate change, river carbon is an important part, while dissolved inorganic carbon (DIC) has a high proportion of river carbon flux. In this study, we did the research on the Lan...Carbon cycle is one of the focuses of climate change, river carbon is an important part, while dissolved inorganic carbon (DIC) has a high proportion of river carbon flux. In this study, we did the research on the Lancang River, an important international river in the southwest of China. Water samples were obtained from 16 sections of the middle and lower reaches of the Lancang River in 2016 (11 months), then we monitored some water quality indicators and DIC content, finally analyzed the temporal-spatial distribution characteristics of DIC and the relationship between DIC content and water environment factors. The results showed that: (1) DIC contents in the middle and lower reaches of the Lancang River varied from 1.1840 mmol/L to 3.1440 mmol/L, with a mean value of about 2.2155 mmol/L. (2) At a time scale, DIC contents of dry season (spring, autumn and winter) were higher than rainy season (summer). At a space scale, DIC contents of the middle and lower reaches of the Lancang River gradually decreased from north to south, and each reservoir had the same characteristics, that is, DIC contents at upstream of the dam was lower than those at downstream of the dam. Compared to other rivers with cascade dams around the world, DIC contents within studied river were at similar level. And the reservoir’s effect of the Lancang River were not obvious, however, DIC contents in the water sampled upstream the dams had a slight stratification. (3) Water temperature, conductivity, turbidity were important factors affecting DIC content of water, and the effect of oxidation and reduction potential (ORP) and pH on DIC was relatively small.展开更多
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.
文摘Carbon cycle is one of the focuses of climate change, river carbon is an important part, while dissolved inorganic carbon (DIC) has a high proportion of river carbon flux. In this study, we did the research on the Lancang River, an important international river in the southwest of China. Water samples were obtained from 16 sections of the middle and lower reaches of the Lancang River in 2016 (11 months), then we monitored some water quality indicators and DIC content, finally analyzed the temporal-spatial distribution characteristics of DIC and the relationship between DIC content and water environment factors. The results showed that: (1) DIC contents in the middle and lower reaches of the Lancang River varied from 1.1840 mmol/L to 3.1440 mmol/L, with a mean value of about 2.2155 mmol/L. (2) At a time scale, DIC contents of dry season (spring, autumn and winter) were higher than rainy season (summer). At a space scale, DIC contents of the middle and lower reaches of the Lancang River gradually decreased from north to south, and each reservoir had the same characteristics, that is, DIC contents at upstream of the dam was lower than those at downstream of the dam. Compared to other rivers with cascade dams around the world, DIC contents within studied river were at similar level. And the reservoir’s effect of the Lancang River were not obvious, however, DIC contents in the water sampled upstream the dams had a slight stratification. (3) Water temperature, conductivity, turbidity were important factors affecting DIC content of water, and the effect of oxidation and reduction potential (ORP) and pH on DIC was relatively small.
