为快速城市化进程中有效理解城市用地功能的时空变化特征提供一种快速有效的创新方法。基于POI(Points of Interest)与RS(Remote Sensing)数据,运用频数密度与类型比例法、核密度分析法,识别长沙市建成区2012年与2022年城市用地功能的...为快速城市化进程中有效理解城市用地功能的时空变化特征提供一种快速有效的创新方法。基于POI(Points of Interest)与RS(Remote Sensing)数据,运用频数密度与类型比例法、核密度分析法,识别长沙市建成区2012年与2022年城市用地功能的变化特征。两期城市用地均呈现混合与单一功能用地“中心-外围”的圈层化地域分布格局,总功能用地增加39.04%;单一的工业用地规模最大且增加最显著,绿地与广场用地以及交通设施用地大大增加;主要的混合功能用地类型不变,但混合度增加16.85%。对比RS识别结果,基于POI数据精细化提取与划分城市单一与混合功能用地进行功能变化特征分析,更加符合实际情况。展开更多
Exploring the scale-effect of different land use types on the distribution pattern of urban park green space(PGS)at multiple grid scales would inform rational allocation and efficient collaborative construction of urb...Exploring the scale-effect of different land use types on the distribution pattern of urban park green space(PGS)at multiple grid scales would inform rational allocation and efficient collaborative construction of urban development land at different scales.Selecting 300-m,500-m,1,000-m,and 2,000-m grid scales,the research employed Create Fishnet tool in ArcGIS and Geodetector to construct a scale-effect analysis framework that revealed the scale-effects of different land use types on the distribution pattern of PGS at multiple grid scales in the main urban area of Nanjing,China in 2006,2012,and 2017.Main research results are:1)the overall distribution pattern of PGS showed the evolution characteristics from polarization to advancing quality and efficiency,while the trend gradually weakened with the increase of grid scale;2)the scale-effect of other land use types on PGS increasingly enhanced-the larger the grid scale,the more obvious the synergistic or compressive effect;3)the interactive scaleeffects of different land use types gradually enhanced-the larger the grid scale,the more significant the overall factor interaction;and 4)at the 300-m grid scale,the major interaction factors were residential,transportation,industrial/manufacturing,water area,and administration/public services,which gradually changed to residential,water area,and administration/public services up to the 2,000-m grid scale.The findings of this paper are expected to deepen the theory of the coupling between PGS and other land use types,as well as provide scientific support and a basis for efficient allocation,spatial layout optimization,and sustainable development of urban spaces.展开更多
Urban land-use/cover changes and their effects on the eco-environment have long been an active research topic in the urbanization field. However, the characteristics of urban inner spatial heterogeneity and its quanti...Urban land-use/cover changes and their effects on the eco-environment have long been an active research topic in the urbanization field. However, the characteristics of urban inner spatial heterogeneity and its quantitative relationship with thermal environment are still poorly understood, resulting in ineffective application in urban ecological planning and management.Through the integration of "spatial structure theory" in urban geography and "surface energy balance" in urban climatology, we proposed a new concept of urban surface structure and thermal environment regulation to reveal the mechanism between urban spatial structure and surface thermal environment. We developed the EcoCity model for regulating urban land cover structure and thermal environment, and established the eco-regulation thresholds of urban surface thermal environments. Based on the comprehensive analysis of experimental observation, remotely sensed and meteorological data, we examined the spatial patterns of urban habitation, industrial, infrastructure service, and ecological spaces. We examined the impacts of internal land-cover components(e.g., urban impervious surfaces, greenness, and water) on surface radiation and heat flux. This research indicated that difference of thermal environments among urban functional areas is closely related to the proportions of the land-cover components.The highly dense impervious surface areas in commercial and residential zones significantly increased land surface temperature through increasing sensible heat flux, while greenness and water decrease land surface temperature through increasing latent heat flux. We also found that different functional zones due to various proportions of green spaces have various heat dissipation roles and ecological thresholds. Urban greening projects in highly dense impervious surfaces areas such as commercial, transportation, and residential zones are especially effective in promoting latent heat dissipation efficiency of vegetation, leading to strongly cooling effect of unit vegetation coverage. This research indicates that the EcoCity model provides the fundamentals to understand the coupled mechanism between urban land use structure and surface flux and the analysis of their spatiotemporal characteristics. This model provides a general computational model system for defining urban heat island mitigation, the greening ratio indexes, and their regulating thresholds for different functional zones.展开更多
文摘为快速城市化进程中有效理解城市用地功能的时空变化特征提供一种快速有效的创新方法。基于POI(Points of Interest)与RS(Remote Sensing)数据,运用频数密度与类型比例法、核密度分析法,识别长沙市建成区2012年与2022年城市用地功能的变化特征。两期城市用地均呈现混合与单一功能用地“中心-外围”的圈层化地域分布格局,总功能用地增加39.04%;单一的工业用地规模最大且增加最显著,绿地与广场用地以及交通设施用地大大增加;主要的混合功能用地类型不变,但混合度增加16.85%。对比RS识别结果,基于POI数据精细化提取与划分城市单一与混合功能用地进行功能变化特征分析,更加符合实际情况。
文摘Exploring the scale-effect of different land use types on the distribution pattern of urban park green space(PGS)at multiple grid scales would inform rational allocation and efficient collaborative construction of urban development land at different scales.Selecting 300-m,500-m,1,000-m,and 2,000-m grid scales,the research employed Create Fishnet tool in ArcGIS and Geodetector to construct a scale-effect analysis framework that revealed the scale-effects of different land use types on the distribution pattern of PGS at multiple grid scales in the main urban area of Nanjing,China in 2006,2012,and 2017.Main research results are:1)the overall distribution pattern of PGS showed the evolution characteristics from polarization to advancing quality and efficiency,while the trend gradually weakened with the increase of grid scale;2)the scale-effect of other land use types on PGS increasingly enhanced-the larger the grid scale,the more obvious the synergistic or compressive effect;3)the interactive scaleeffects of different land use types gradually enhanced-the larger the grid scale,the more significant the overall factor interaction;and 4)at the 300-m grid scale,the major interaction factors were residential,transportation,industrial/manufacturing,water area,and administration/public services,which gradually changed to residential,water area,and administration/public services up to the 2,000-m grid scale.The findings of this paper are expected to deepen the theory of the coupling between PGS and other land use types,as well as provide scientific support and a basis for efficient allocation,spatial layout optimization,and sustainable development of urban spaces.
基金financially supported by the Major Projects of the National Natural Science Foundation of China (Grant No. 41590842)General Program of the National Natural Science Foundation of China (Grant No. 41371408)
文摘Urban land-use/cover changes and their effects on the eco-environment have long been an active research topic in the urbanization field. However, the characteristics of urban inner spatial heterogeneity and its quantitative relationship with thermal environment are still poorly understood, resulting in ineffective application in urban ecological planning and management.Through the integration of "spatial structure theory" in urban geography and "surface energy balance" in urban climatology, we proposed a new concept of urban surface structure and thermal environment regulation to reveal the mechanism between urban spatial structure and surface thermal environment. We developed the EcoCity model for regulating urban land cover structure and thermal environment, and established the eco-regulation thresholds of urban surface thermal environments. Based on the comprehensive analysis of experimental observation, remotely sensed and meteorological data, we examined the spatial patterns of urban habitation, industrial, infrastructure service, and ecological spaces. We examined the impacts of internal land-cover components(e.g., urban impervious surfaces, greenness, and water) on surface radiation and heat flux. This research indicated that difference of thermal environments among urban functional areas is closely related to the proportions of the land-cover components.The highly dense impervious surface areas in commercial and residential zones significantly increased land surface temperature through increasing sensible heat flux, while greenness and water decrease land surface temperature through increasing latent heat flux. We also found that different functional zones due to various proportions of green spaces have various heat dissipation roles and ecological thresholds. Urban greening projects in highly dense impervious surfaces areas such as commercial, transportation, and residential zones are especially effective in promoting latent heat dissipation efficiency of vegetation, leading to strongly cooling effect of unit vegetation coverage. This research indicates that the EcoCity model provides the fundamentals to understand the coupled mechanism between urban land use structure and surface flux and the analysis of their spatiotemporal characteristics. This model provides a general computational model system for defining urban heat island mitigation, the greening ratio indexes, and their regulating thresholds for different functional zones.