Research On The Spatial Evolution Process And Mechanism Of The Industrial Ecological Network Of The Middle Yangtze River Urban Agglomeration

The urban agglomeration industrial ecology network is a networked and ecologized expression of the urban agglomeration industrial ecosystem,serving as a crucial lever for territorial spatial planning and ecological environmental protection.Cities are gradually evolving from spaces organized around production factors to "flow spaces," and the urban agglomeration industrial ecology network represents one of the developmental trends of urban spatial structures.Industrial flows,ecological flows,industrial linkages,ecological linkages,and the connections between industry and ecology become vital bonds within the urban agglomeration industrial ecology network.Urban agglomerations are not only the primary concentration areas for human socioeconomic activities,important bearers of industrial development,and consumption sites for resource utilization but also focal areas for cross-jurisdictional governance and ecological protection.However,rapid and dispersed urban expansion,along with changes in the ecological environment,are profoundly affecting the characteristics and patterns of the urban agglomeration industrial ecology network.Influenced by various factors including the natural geographical environment,socio-economic conditions,and technological levels,the network exhibits multiple development models.Therefore,in the context of ecological safety and achieving carbon peak and carbon neutrality,studying the spatial evolution process and mechanism of the urban agglomeration industrial ecology network can not only broaden the understanding and research scope of industrial ecology networks but also provide empirical references for the sustainable development of regional industrial ecology.Selecting 31 cities from the Middle Yangtze River Urban Agglomeration as research samples,the content is studied through the research logic structure of "network characterization-pattern identification-evolution process-evolution mechanism",providing new theoretical connotations and methodological approaches for the spatial evolution process and mechanism of urban agglomeration industrial ecological networks.Firstly,based on the theories of complex ecosystems,flow space,and complex networks,a new connotation of urban agglomeration industrial ecological networks is defined,and the principle of spatial evolution of urban agglomeration industrial ecological networks based on the concept of "flow space" is constructed.Secondly,by coupling industrial economy,landscape ecology,and circular economy among multiple disciplines,a comprehensive evaluation index system is built.The modified gravity model is used to measure the intensity of industrial ecological flows between cities,proposing a spatial identification method for urban agglomeration industrial ecological networks and exploring the spatial pattern and network structure of the industrial ecological network in the Middle Yangtze River Urban Agglomeration.Thirdly,the evolution process of the industrial ecological network in the Middle Yangtze River Urban Agglomeration is clarified from the network logic of "node-skeleton(line)-form(surface)-plate".Finally,the coupled geographic detector,spatio-temporal weighted regression model and fixed effect model reveal the spatial evolution of urban agglomeration industrial ecological network "driving factor-key driving factor-dominant factor",and the coupled spatial Durbin model and the secondary assignment program reveal the spatial evolution mechanism of urban agglomeration industrial ecological network.The main research conclusions are as follows:From 2005 to 2020,the spatial distribution of industrial ecological sustainability in the Middle Yangtze River Urban Agglomeration was uneven,showing an upward trend over time.The spatial distribution pattern of node industrial attributes evolved from a "one primary,two secondary" pattern to a "one primary,one secondary," and then to a "dual-center" structure.The ecological attributes exhibited a "high in the south,low in the north" spatial distribution characteristic,with high values concentrated in the Chang-Zhu-Tan Urban agglomeration and the Poyang Lake Urban agglomeration.The spatial distribution pattern of resource and environmental attributes evolved from "low in the center,high in the periphery" to "low in provincial capitals,high in surrounding areas."From 2005 to 2020,the relative centrality,indegree,outdegree,internal closeness centrality,external closeness centrality,and betweenness centrality of nodes in the industrial ecological network of the Middle Yangtze River Urban Agglomeration showed a "generally relatively stable,with local fluctuations" spatial evolution characteristic.The core-periphery structure’s core area was concentrated in the Wuhan Metropolitan Area.From the perspective of the skeleton(line)evolution process,the regional grouping phenomenon of the industrial ecological network in the Middle Yangtze River Urban Agglomeration was evident,with cities in the northeast and southwest directions dominating its spatial pattern evolution over time.The "central collapse" phenomenon gradually eased,forming three zonal,fan-shaped,and circular skeletons: "Yiyang-Changsha-Xiangtan-Zhuzhou-Pingxiang-Yichun-Xinyu-Ji’an," "Xiaogan-Wuhan-Huanggang-Ezhou-Huangshi," and "Nanchang-Fuzhou-YingtanShangrao-Jingdezhen-Jiujiang-Nanchang." From the perspective of network morphology evolution,the form of the industrial ecological network in the Middle Yangtze River Urban Agglomeration evolved from "single-line dominance" to "dualband emergence," and then to a coexistence of bands,fans,and circles.In terms of plate characteristics,the industrial ecological network of the Middle Yangtze River Urban Agglomeration overall showed a self-reflective structural feature,with intra-plate communication being primary and inter-plate communication being secondary.The key driving factors for the spatial evolution of the industrial ecology network of the urban agglomeration in the middle reaches of the Yangtze River are the level of economic development,industrialization,energy efficiency,financial development,market consumption,digital technology innovation,industrial structure upgrading,urbanization,and government governance.The interaction types between dual factors are mainly dual-factor enhancement,supplemented by nonlinear enhancement.From the perspective of spatial-temporal differentiation,the impact of economic development has shifted from negative to positive,showing a "high in the west,low in the east" pattern;the positive impact of industrialization has increased,and the negative impact has decreased,forming an "east high,west low" distribution;the positive impact of energy efficiency has weakened,with low-value areas concentrated in the northeast;the positive impact of financial development has increased then decreased,mainly concentrated around the Yi Jing Jing,Chang-Zhu-Tan,and Poyang Lake urban agglomerations;the positive impact of market consumption has decreased,and the negative has increased,but the low-value areas have decreased;the positive impact of digital technology innovation shows a "C" shaped distribution,but the covered area has decreased;the impact of industrial structure has strengthened negatively from west to east;the positive impact of urbanization has increased,mainly extending southward to the Chang-Zhu-Tan urban agglomeration;government governance is dominated by positive impacts,concentrated in the western and central regions of the study area.Industrial structure upgrading,energy efficiency,government governance,and technological innovation are the dominant factors in the spatial evolution of the industrial ecological network in the Middle Yangtze River Urban Agglomeration.Industrial structure upgrading and technological innovation have a time cumulative effect on the impact of node industrial ecological attributes;energy efficiency has temporal heterogeneity and phase characteristics in its impact on node industrial ecological attributes;government governance has a long-term impact on node industrial ecological attributes.From the perspective of the spatial evolution spillover mechanism,industrial structure upgrading,government governance,and energy efficiency have a spatial cooperative effect on the spatial evolution of the industrial ecological network in the Middle Yangtze River Urban Agglomeration,while technological innovation has a spatial competitive effect.From the perspective of the spatial evolution correlation mechanism,geographical proximity is a fundamental factor in the formation of the industrial ecological network in the Middle Yangtze River Urban Agglomeration.The differences in the level of green innovation promote the formation and strengthening of industrial ecological flows between cities.The convergence of land use intensity and the level of economic development support the establishment of industrial ecological connections between cities.The differences in urbanization level and energy consumption intensity strengthen the exchange and cooperation in industrial ecology among cities of different sizes,further promoting the spatial evolution of the industrial ecological network.The convergence and convergence of environmental regulation intensity between cities ensure the exchange of green-related knowledge and technology,promoting the formation and deepening of industrial ecological connections between cities.The innovations of this paper are as follows:(1)Based on the theory of composite ecosystems,starting from the interrelationship among industry,resources,environment,and ecology,it defines the new connotation of urban agglomeration industrial ecosystems and industrial ecological networks.It proposes a spatial identification method for the urban agglomeration industrial ecological network based on "index calculation-industrial ecological flow measurement-network spatial identification."(2)Integrate the network characterization and feature analysis based on "point-line-plane" and the spatial analysis based on "pattern-process-mechanism",and construct the spatial evolution analysis framework of urban agglomeration industrial ecological network with "network measurement-pattern characterization-process analysis-factor screening-evolution mechanism" as the main line.(3)The "driving factor-key driving factor-dominant factor" of the spatial evolution of the industrial ecological network of urban agglomeration is proposed by coupling the geographical detector,the spatial-temporal weighted regression model and the fixed-effect model,and the spatial evolution mechanism model of the industrial ecological network of urban agglomeration is proposed by coupling the spatial Durbin model and the Quadratic Assignment Procedure.