Globalization and informatization have accelerated city networking process over the world, which makes research on city network a hot topic in the fields of urban geography and economic geography. With Chinese economi...Globalization and informatization have accelerated city networking process over the world, which makes research on city network a hot topic in the fields of urban geography and economic geography. With Chinese economic structure adjustment and city economic growth, producer services have begun to play an increasingly important role in city-region networking. This paper employs the methodology of world city network to analyze and explain the spatial development characteristics of China's urban network system based on the data of nationwide producer services enterprise network. The research result indicated that the distribution of producer services network has a positive effect on the development of Chinese city networks. City network connectivity is closely related to the significance of city in producer services development, and the former will gradually decline with the drop of the latter. Accordingly, the 64 cities can be divided into the national central cities, regional central cities, sub-regional central cities and local central cities in accordance with their position and role in the nationwide producer services network. It is concluded that high-grade cities with quality producer services dominate the pattern of Chinese city networks and there emerges three spatial agglomerations of producer services enterprises in Changjiang (Yangtze) River Delta, Zhujiang (Pearl) River Delta and Beijing-Tianjin-Tangshan Economical Region. Moreover, the distribution of different producer services industry varies from city to city, which also affects the characteristics of network development.展开更多
Recently, urban high temperature phenomenon has become a problem which results from human activities, the increase in energy consumption, and land-cover change in urban areas. As extremely hot weather caused by urban ...Recently, urban high temperature phenomenon has become a problem which results from human activities, the increase in energy consumption, and land-cover change in urban areas. As extremely hot weather caused by urban high temperature continues, demand for power is increased and results in the degradation of electricity reserves. The current trend in climate change, regardless of the summer and winter power demand, is likely to have much effect on the power demand. Thus, sensitivity to electricity consumption in urban areas due to climate change was researched. The results show that, 1） the basic unit of the sensitivity to electricity consumption in the target areas is 1.25-1.58W/（m2.℃）; 2） The maximum sensitivity is recorded at around 8：00 pm in the area crowded with commercial and business area. And in the business area, electricity consumption load is even from 9：00 am to 6：00 pm.展开更多
By using the global atmospheric general circulation model CAM4.0 including an urban canopy parameterization scheme,the possible impacts of large-scale urbanization in East China on East Asian winter monsoon was invest...By using the global atmospheric general circulation model CAM4.0 including an urban canopy parameterization scheme,the possible impacts of large-scale urbanization in East China on East Asian winter monsoon was investigated via idealized numerical experiments.Results suggest that large-scale urbanization can cause a significant warming effect in both surface temperature and air temperature near the surface over most areas of East China.Meanwhile,large-scale urbanization also alters the surface energy balance,causing evident increases in net surface long-wave radiation and sensible heat flux as well as intensified surface thermal heating to the atmosphere.Forced by the surface thermal heating anomalies induced by the large-scale urban expansion,East Asian winter monsoon circulation exhibits distinct changes.Overall,the extensive urbanization over East China will weaken East Asian winter monsoon,but intensify winter monsoon in northeast China.展开更多
Delimitation of an urban growth boundary(UGB)can effectively curb disorderly urban expansion,optimize urban development space and protect the ecological environment.Eco-environmental sensitivity was evaluated and area...Delimitation of an urban growth boundary(UGB)can effectively curb disorderly urban expansion,optimize urban development space and protect the ecological environment.Eco-environmental sensitivity was evaluated and areas prohibiting construction expansion were extracted by establishing an index system.Point of interest(POI)and microblog data were utilized to analyze the expansion of residential activity space.Urban space expansion potential was calculated using a comprehensive evaluation model,and an urban growth boundary for Jinan in 2020 was delimited combining the predicted urban expansion scale.The results showed that:(1)An evaluation of eco-environmental sensitivity can effectively protect ecological land and provide an ecological basis for urban expansion.Regions with high eco-environmental sensitivities in Jinan are located along the banks of the Yellow River and Xiaoqing River and in southeast mountainous areas,but eco-environmental sensitivities in the central,north and southeast areas are relatively low;(2)The model to evaluate urban residential activity expansion can quantify the spatial distribution of urban residents’activities.Regions with high potential for residential activity space expansion in Jinan are mainly concentrated in the middle of Jinan and most are part of existing built-up areas and surrounding areas;(3)The method that delimits urban growth boundaries based on the coordination of ecology and residential activity space is reasonable.Spatial expansion in Jinan mainly extends towards the east and west wings,and the boundary conforms to the spatial strategy guiding Jinan’s development and is consistent with the overall layout in related plans.Considering both ecological protection and the internal forces driving urban expansion,the method of urban growth boundary delimitation used in this study can provide a reference and practical help for studies and management of urban development in the new era.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.40971094)
文摘Globalization and informatization have accelerated city networking process over the world, which makes research on city network a hot topic in the fields of urban geography and economic geography. With Chinese economic structure adjustment and city economic growth, producer services have begun to play an increasingly important role in city-region networking. This paper employs the methodology of world city network to analyze and explain the spatial development characteristics of China's urban network system based on the data of nationwide producer services enterprise network. The research result indicated that the distribution of producer services network has a positive effect on the development of Chinese city networks. City network connectivity is closely related to the significance of city in producer services development, and the former will gradually decline with the drop of the latter. Accordingly, the 64 cities can be divided into the national central cities, regional central cities, sub-regional central cities and local central cities in accordance with their position and role in the nationwide producer services network. It is concluded that high-grade cities with quality producer services dominate the pattern of Chinese city networks and there emerges three spatial agglomerations of producer services enterprises in Changjiang (Yangtze) River Delta, Zhujiang (Pearl) River Delta and Beijing-Tianjin-Tangshan Economical Region. Moreover, the distribution of different producer services industry varies from city to city, which also affects the characteristics of network development.
基金Project(NRF-20110030631) supported by the National Research Foundation of Korea Grant funded by the Korean Government
文摘Recently, urban high temperature phenomenon has become a problem which results from human activities, the increase in energy consumption, and land-cover change in urban areas. As extremely hot weather caused by urban high temperature continues, demand for power is increased and results in the degradation of electricity reserves. The current trend in climate change, regardless of the summer and winter power demand, is likely to have much effect on the power demand. Thus, sensitivity to electricity consumption in urban areas due to climate change was researched. The results show that, 1） the basic unit of the sensitivity to electricity consumption in the target areas is 1.25-1.58W/（m2.℃）; 2） The maximum sensitivity is recorded at around 8：00 pm in the area crowded with commercial and business area. And in the business area, electricity consumption load is even from 9：00 am to 6：00 pm.
基金supported by the National Basic Research Program of China(2010CB428505 and 2011CB952004)Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institu-tions(PAPD)
文摘By using the global atmospheric general circulation model CAM4.0 including an urban canopy parameterization scheme,the possible impacts of large-scale urbanization in East China on East Asian winter monsoon was investigated via idealized numerical experiments.Results suggest that large-scale urbanization can cause a significant warming effect in both surface temperature and air temperature near the surface over most areas of East China.Meanwhile,large-scale urbanization also alters the surface energy balance,causing evident increases in net surface long-wave radiation and sensible heat flux as well as intensified surface thermal heating to the atmosphere.Forced by the surface thermal heating anomalies induced by the large-scale urban expansion,East Asian winter monsoon circulation exhibits distinct changes.Overall,the extensive urbanization over East China will weaken East Asian winter monsoon,but intensify winter monsoon in northeast China.
基金National Natural Science Foundation of China(41430861)
文摘Delimitation of an urban growth boundary(UGB)can effectively curb disorderly urban expansion,optimize urban development space and protect the ecological environment.Eco-environmental sensitivity was evaluated and areas prohibiting construction expansion were extracted by establishing an index system.Point of interest(POI)and microblog data were utilized to analyze the expansion of residential activity space.Urban space expansion potential was calculated using a comprehensive evaluation model,and an urban growth boundary for Jinan in 2020 was delimited combining the predicted urban expansion scale.The results showed that:(1)An evaluation of eco-environmental sensitivity can effectively protect ecological land and provide an ecological basis for urban expansion.Regions with high eco-environmental sensitivities in Jinan are located along the banks of the Yellow River and Xiaoqing River and in southeast mountainous areas,but eco-environmental sensitivities in the central,north and southeast areas are relatively low;(2)The model to evaluate urban residential activity expansion can quantify the spatial distribution of urban residents’activities.Regions with high potential for residential activity space expansion in Jinan are mainly concentrated in the middle of Jinan and most are part of existing built-up areas and surrounding areas;(3)The method that delimits urban growth boundaries based on the coordination of ecology and residential activity space is reasonable.Spatial expansion in Jinan mainly extends towards the east and west wings,and the boundary conforms to the spatial strategy guiding Jinan’s development and is consistent with the overall layout in related plans.Considering both ecological protection and the internal forces driving urban expansion,the method of urban growth boundary delimitation used in this study can provide a reference and practical help for studies and management of urban development in the new era.
