Assessing 40 years of spatial dynamics and patterns in megacities along the Belt and Road region using satellite imagery  

作　　者：Zhongchang Sun Sisi Yu Huadong Guo Cuizhen Wang ZengXiang Zhang Ru Xu 

机构地区：[1]Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing,People’s Republic of China [2]Key Laboratory Earth Observation Hainan Province,Sanya Institute of Remote Sensing,Sanya,People’s Republic of China [3]University of Chinese Academy of Sciences,Beijing,People’s Republic of China [4]Department of Geography,University of South Carolina,Columbia,SC,USA [5]State Key Laboratory of Earth Surface Processes and Resource Ecology,Faculty of Geographical Science,Beijing Normal University,Beijing,People’s Republic of China

出　　处：《International Journal of Digital Earth》2021年第1期71-87,共17页国际数字地球学报（英文）

基　　金：supported by the Key R&D Program Projects in Hainan Province(grant number ZDYF2019008);Strategic Priority Research Program of the Chinese Academy of Sciences(grant number XDA19030104);National Key 84 Z.SUN ET AL.Research and Development Program(grant number 2016YFA0600302);the National Natural Science Foundation of China(grant number 41201357).

摘　　要：The Belt and Road(B&R)region,a vital area with historical,economic,cultural and political significance,has undergone rapid urbanization in the past several decades,especially in the form of urban expansion.In this study,20 megacities in the B&R region were selected to explore different spatiotemporal patterns of urban expansion.Object-oriented support vector machines(SVM),annual growth rate(AGR)models,and landscape metrics were employed to delineate the urban areas and characterize spatiotemporal characteristics and landscape patterns of these megacities during 1975–2015.All urban maps presented high overall accuracies(80.70%–95.90%)and overall Kappa coefficients(0.76–0.95).The study revealed that megacities in the B&R region have undergone different types of urban sprawl,mainly adopting a‘concentric circle’pattern in inland areas and a‘sector’pattern in coastal areas.Besides,six expansion modes were summarized according to the AGRs of individual megacities.Differences existed in megacities of the developing and developed countries and among five sub-regions.Moreover,‘dispersion,gathering,and re-dispersion’and‘coalescence’were two major landscape patterns of megacities in developing and developed countries.Results of this study can provide a scientific reference for urban planning and aid in sustainable development of local areas.

关 键 词：Belt and Road(B&R) MEGACITIES spatiotemporal expansion landscape pattern regional differentiations 

分 类 号：TU9[建筑科学]