Comprehensive Response Of Urban Elements And Thermal Environment In Urban Agglomeration Based On Remote Sensed Information

Urbanization in Europe has generally experienced three processes,which are urbanization,anti-urbanization and re-urbanization.The Yangtze River Delta urban agglomeration with rapid development of urbanization in China has entered the stage of �anti-urbanization� or �re-urbanization,� and its phased characteristics of urbanization and urban sprawl have resulted in facing a severe regional ecosystem pressure.Remote sensing information can reflect the effects and impacts of urban ecosystem changes.In this study,the open space and physical space of urban ecosystems are analyzed in The Yangtze River Delta urban agglomeration,which was selected as the research area,and compared with the Western European urban agglomeration with different urbanization stages.The comprehensive response based on urban factors and the urban thermal environment is the main point.Specifically,response relationship characteristics,effects and impact,and the suitability of spatial analysis scale are analyzed.From the urban relations of the urban groups in the region aspect,the urban space and composition of the urban aspect,and the structure and function of the district aspect,with the methods of classifying the urban surface energy thresholds,spatial analysis of the urban factors,etc.the pattern of urban factor composition and change are explored,and discussed in state,quality characteristics and laws.The results show:Regional-In the process of urbanization of Yangtze River Delta urban agglomeration,the scale and intensity of urban expansion exceed Western European urban agglomerations.An obvious surface energy aggregation shows in the urban areas,and the scale of high-value energy patches expands significantly;The surface energy level of open spaces and the growth rate of high-value energy patches have increased as a whole,and the difference of the surface energy levels between urban elements and natural elements has increased;The influence of the urban elements on the thermal environment of the Yangtze River Delta region was larger than the influence in the Western European region,and the impact of the nearest distance factor of built-up area on the regional thermal environment was more obviously than the impact of proportion factor of the built-up area,which was reflected in both research areas.Urban-Relative to cities in Western Europe,the urban sprawl of the cities in Yangtze River Delta is more significant;The vegetation cover in the urban physical space is extremely low,and the volume is small,leading to the accumulation of highenergy plaque,which reflect sharp contrast to cities in Western Europe;The vegetation of the open space outside the physical space reduced,leading to the weaken of the buffer and transition of surface energy between the physical space and the open space in the Yangtze River Delta,which shows a steep change on the surface energy level;The physical space of the cities in Yangtze River Delta had a great influence on the thermal environment,while the physical space of the Western Europe cities has indistinctive influence.Districts-The imbalance of the building mass,density,height,and functional composition in the districts of the Yangtze River Delta cities leads to a high concentration of surface energy;The industrial districts present an unstable phenomenon with high-distribution of high surface energy patches,and the historic districts present a relatively stable phenomenon with high-distribution of high surface energy patches;Multi-storey buildings have a certain degree of surface energy adjustment effect based on the same building density;The proportion of buildings,the configuration of physical space and open space,and the configuration of different heights of buildings should be reasonably planned and controlled in the district planning.The purpose of the research is using remote sensing information to explore the relationship between the surface energy response of the urban space and interpreting the problems of the ecological system from the aspects of structural characteristics,group formation methods,spatial allocation of urban elements,and to provide a scientific basis for the improvement of urban space quality.