Polarization or Diffusion?Spatio-temporal Evolution of Urban Technological Innovation Capacity in China's Five Urban Agglomerations

Under the background of collaborative innovation,innovation spillovers at urban agglomeration(UA)level is an important issue but rarely discussed.Using balanced panel data of innovation activities in China’s five UAs from 2003 to 2016,this paper shows spatio-temporal evolution process of their technological innovation capacity with discussing polarization-diffusion patterns,and simultaneously examines driving factors of that evolution processes.We report three main findings:1)there is a high degree of concentration in technological innovation capacity distribution within all China’s five UAs,linked by economic and innovation collaboration.2)Innovation capacity increase of China’s five UAs is driven by government’s investment in science and technology(S&T)to a large extent,followed by influences of infrastructure facilities construction,human capital for S&T,as well as transformation of industrial structure,with great disparities emerged between UAs in our sample period.3)While the intra-region innovation gaps are reducing in Yangtze River Delta Urban Agglomeration(YRD)with obvious innovation diffusion,urban agglomeration in middle reaches of the Yangtze River(MYR)is still dominated by innovation polarized growth.Differences in polarization-diffusion patterns between these two UAs may be explained by opposite returns of industrial structure and internet infrastructure.Our findings contribute to more effective policy making in promoting innovation development when reducing regional inequality through innovation diffusion.

China’s urban green innovation:Regional differences,distribution dynamics,and convergence

Urban green innovation(UGI)is essential to environmental protection,ecological conservation,and high quality economic growth.Using green patents,our study assessed the level of UGI of 287 Chinese cities at and above the prefecture level.Then,using the Dagum Gini coefficient,kernel density estimation(KDE),and con‐vergence models,we examined regional differences,distribution dynamics,and convergence of UGI across China.The study’s findings are as follows:(1)Overall,regional differences in UGI tended to narrow,and the main contributor to these differences was the difference between economic zones.(2)KDE showed that the level of UGI was rising,which was polarized within each economic zone.(3)The national UGI in economic zones other than the Northeast and Middle Yellow River Economic Zones featured significantσconvergence,while each economic zone showed absolute and conditionalβconvergence.

Impact of Chinese Local Government-led Construction Land Supply Strategies on Urban Innovation and its Spatiotemporal Differences

This study constructs a theoretical framework to analyze the impact of local governmentled construction land supply(LGCLS)strategies on urban innovation.It uses data related to 265 cities in China from 2005 to 2019 for empirical analysis.Its conclusions are as follows.For development stage differences,the impact of LGCLS strategies on urban innovation exhibited an inverted U shape with economic growth.The inflection point occurred when the per capita GDP equaled approximately RMB23,101 in 2008.For regional diferences,the inflection point in eastern China is higher and earlier than that in central and western China;before the inflection point,the positive infuence was more obvious in the central and western regions,whereas after the inflection point,the negative influence was more obvious in the eastern region.For the eastern Yangtze River Delta urban agglomerations and the northwestern resource-based urban agglomerations with relatively high per capita GDP,the negative impact of LGCLS strategies on urban innovation occurred earlier and showed spatial agglomeration characteristics.