Study On The Characteristics And Diffusion Effect Of Carbon Linkage Network Among Inter-industry Sectors

With the deepening of China’s industrialization and urbanization,the climate problems caused by industrial production and human activities are becoming more and more serious.As a major carbon emitter,China’s carbon emissions account for one quarter of the global total.The problem of carbon emissions poses a serious threat to the ecological environment,and emission reduction actions are imminent.Industrial sector as the main source of carbon emissions,complex production and consumption are connected,the change of a industry technical level and other factors cause a fluctuation of the carbon industry,these fluctuations due to the industry association in the industry of carbon emissions system spread,cause entrainment carbon exist between industry and diffusion effect,the influence on the carbon emissions of the whole system.Therefore,it is of great significance to analyze the evolution characteristics of industrial carbon emission related network and clarify the diffusion relationship between industrial sectors for the formulation of carbon emission reduction policies.Taking industrial sectors as the research object,this paper measures carbon emissions and carbon emission intensity based on the input-output data of 2007,2010,2012,2015 and 2017,and reveals the evolutionary characteristics of carbon emissions and carbon emission intensity over the years.On this basis,the complete carbon emission intensity data is used to construct the industrial carbon emission correlation network,and the characteristics of the whole and individual networks are analyzed with the help of network indicators to reveal the specific structure of the correlation network.Further,consider sectors supply side and demand side,using the k-shell carbon decomposition technique to build industry supply network and k-shell demand network,using nuclear centricity,nuclear radiation,k-shell entropy of three kinds of network diffusion index,quantitative carbon swings in industry the degree of mutual influence,in the network to identify the industry influence,The diffusion effect of industry in the network is revealed from the global level,which provides an important basis for proposing the carbon emission reduction policy of industrial system.The main conclusions are as follows :(1)From the perspective of carbon emissions,the total direct carbon emissions show an increasing trend,with a total increase of 3.861 billion tons from 2007 to 2017,an increase of about 1.5 times.From the perspective of carbon emission intensity,the carbon emission intensity of most industrial sectors showed a downward trend.(2)The industrial carbon related network density showed a sharp decline from 0.722 to 0.398 during 2007-2012,and then stabilized at about0.4.The network has a small average shortest path and high aggregation coefficient,which has the characteristics of small world.During the study period,the carbon emission intensity and input intensity of industrial sectors fluctuated,but the ranking was relatively stable.Oil and gas mining,metal mining and dressing,non-metal mining and other mining and dressing industries have high intermediate center degree and close to center degree,and are in the core position.(3)For the k-shell supply network of industrial carbon emissions,the centrality of each department in the core is obviously different.During the study period,the overall diffusion effect of most industrial sectors decreased,and the phenomenon of "single dominant industry" was gradually weakened.The k-shell entropy of metal smelting and rolling processing industry and non-metallic mineral products industry rank high over the years,and the diffusion effect is large.(4)For the k-shell demand network of industrial carbon emissions,the centrality of core degree in most industrial sectors is obviously greater than that of core degree out.After 2012,the distribution of core degree centrality in all sectors is in a scattered state.The mean value of the overall diffusion effect of the nuclear industry increased at first and then slightly decreased,increasing from 0.241 in 2007 to 0.545 in 2012 and then decreasing to 0.473 in 2017.For the k-into shell entropy,the industrial departments at all levels of the demand structure are in a relatively balanced situation.