Impact Of Urban Space On Air Quality And Planning Response Research In Winter Cities

Deteriorating air quality has become a globe environmental issue.In China,air quality is also getting worse now.Our government has successively launched various policies and measures to promote the improvement of air quality in an orderly manner.In 1973,the first national environmental protection conference held by the State Council proposed that the improvement of air quality should be carried out mainly through the governance of industrial point sources.In the 1980 s,air quality improvement efforts moved from point source governance to integrated prevention and treatment.Since the 1990 s,China's air quality control work began to shift from concentration control to total volume control,and from comprehensive urban environmental remediation to regional pollution control.Driven by various policies and measures,China's air quality improvement work has made great progress.However,compared with the expected goal of environmental governance,the total emission of air pollutants in China is still perennially high,and heavy pollution and smog have become the "new normal" in the process of urbanization.So it is urgent to make a breakthrough in air quality improvement.Given the urgency and importance of air quality improvement,how to improve air quality has become a topic of concern for scholars.At present,a large number of studies have been conducted on air quality issues.As far as the research area is concerned,they mainly focus on first-tier cities such as Beijing and Shanghai.In terms of study period,more attention is paid to the air quality of a particular event or a heavily polluted weather.However,there are relatively few studies on cold regions,and there are even less researches on the relationship between urban air quality and urban space in winter cities.Winter cities are greatly influenced by the regional climate.There are cold in winter and hot in summer,raining and hot during the same period,and have four distinct seasons.The air quality there is markedly different between poor in winter and good in summer.Especially during the heating period in winter,the soot-type pollution is extremely serious.At the same time,there are a large number of heavy-industry enterprises in winter cities.Among them,Harbin,Shenyang,Changchun and other old industrial base cities,the industry-led urbanization mode of development has led to serious urban air pollution problems.As a cold region with a high urbanization rate in China,population concentration has led to high-density development of urban land and rapid growth in urban traffic.Traffic pollution has gradually become an important factor influencing air quality.In general,the air quality of cities in winter cities is declining under the triple pressure of soot-type pollution,industrial pollution and traffic pollution.This paper takes the winter cities as the study area,and follows the idea of "discovering problems-analyzing problems-planning and responding" to provide a planning basis for improving the ecological environment and promoting the sustainable development of winter cities.First,base on relevant domestic and international research,combing with the characteristics of winter cities,choose the typical winter city of Harbin as the subject to investigate air quality and urban space.The investigation includes air quality investigation and urban space investigation,among them,the air quality investigation includes investigation on air quality change characteristics,air quality index measurements and key pollution sources investigation.Urban space investigation includes characteristics of urban space evolution,investigation on urban land use and investigation on spatial form.Base on the investigation results,we summarize the current problems of Harbin urban space from the perspective of air quality.Secondly,the Identification of urban spatial risk areas in Harbin from the perspective of air quality was carried out based on the air quality perspective.The identification includes a spatial analysis of air quality,zoning of air qualit y impact levels,urban land use characteristics of different air quality zones,and urban risk zone types.The spatial analysis of air quality includes the spatial distribution of air quality at the status quo level and the spatial distribution of air qual ity at the theoretical level.Through the analysis of the interpolation of status quo air quality and the analysis of the theoretical influence range of air pollution sources,we identified four air quality impact zones in Harbin by using the natural break point analysis,intersection analysis and superposition analysis,and analyzed the urban land use characteristics of different air quality zones.Based on the results of air quality impact zoning and urban land use characteristics of different air quality zones,Harbin was divided into 4 large risk areas,25 medium risk areas and 41 small risk areas.Meanwhile,going down to the block scale,an urban spatial characterization analysis was carried out on four large risk areas,25 medium risk areas and 41 smal l risk areas in Harbin.The analysis of urban spatial characteristics include urban land characteristics and urban spatial form characteristics.Urban land characteristics analysis include land use ratio,land use type,land layout and land concentration,and urban spatial pattern analysis includes building height and building density.The law of the influence of urban space on air quality in Harbin is summarized through the layer-by-layer advancing analysis of urban spatial characteristics of large risk ar eas,medium risk areas and small risk areas.Finally,based on the above-mentioned research,the paper proposes to address the urban spatial planning response system based on air quality improvement.The response system includes four aspects: the definition of the control level of urban space,the planning and optimization strategies of urban land,the planning and response strategies of urban spatial form and the planning guarantee strategy.The definition of control levels is based on the law of the influ ence of urban space on air quality,divide the city of Harbin into control levels.The planning and optimization strategy for urban industrial land includes the definition of key control scope of urban land use,industrial land,transportation land and green space.The planning and response strategies for urban spatial form include the definition of key control scope of urban spatial form,building density,building height and other spatial form elements.The planning guarantee strategies includes three asp ects: policy guarantee,implementation mechanism and governance mechanism.Impact of urban space on air quality and planning response in winter cities,based on the background of severe cold climate,this paper is committed to clarify the impact law of urban space and air quality,and explore the planning path to improve the air quality of cold city.This research will also provide certain planning support for the improvement of the living environment in winter cities.