Measurement of Digital Economy Development Level in Yangtze River Delta and Its Influence on Ecological Efficiency

Based on the panel data of 41 cities in the Yangtze River Delta from 2007 to 2018,this paper empirically tests the impact of digital economy development on urban ecological efficiency in the Yangtze River Delta.The results show that the development level of digital economy in Yangtze River Delta urban agglomeration is fluctuating and rising;the development of digital economy has a significant positive role in promoting the improvement of urban ecological efficiency;there is significant regional heterogeneity in the promotion of ecological efficiency by digital economy,especially in central cities.

The Effect of Urban Agglomeration Expansion on PM_(2.5) Concentrations: Evidence from a Quasi-natural Experiment

This study constructs a quasi-natural experiment based on the expansion of the Yangtze River Delta urban agglomeration(YRDUA) of China in 2010 to investigate the impact and inner mechanism of urban agglomeration expansion on fine particulate matter(PM_(2.5)) concentrations through propensity scores in difference-in-differences models(PSM-DID) using panel data from 286 prefecturelevel cities in China from 2003 to 2016. The results show that 1) urban agglomeration expansion contributes to an overall decrease in PM_(2.5)concentration, which is mainly achieved from the original cities. For the new cities, on the other hand, the expansion significantly increases the local PM_(2.5)concentration. 2) In the long term, the significant influence of urban agglomeration expansion on PM_(2.5)concentration lasts for three years and gradually decreases. A series of robustness tests confirm the applicability of the PSM-DID model.3) Cities with weaker government regulation, a better educated population and higher per capita income present stronger PM_(2.5)reduction effects. 4) Urban agglomeration expansion affects the PM_(2.5)concentration mainly through industrial transfer and population migration, which cause a decrease in the PM_(2.5)concentration in the original cities and an increase in the PM_(2.5)concentration in the new cities.Corresponding policy suggestions are proposed based on the conclusions.

Industrial carbon emissions and influencing factors in the Yangtze River Delta urban agglomeration

This paper calculates the industrial carbon emissions of the Yangtze River Delta urban agglomeration over the period 2006-2013. An empirical analysis is conducted to find out the influencing factors of industrial carbon emissions of the Yangtze River Delta urban agglomeration, using a spatial Durbin panel model. The results show that cities with larger industrial carbon emissions often enjoy low annual growth rates, while the cities with smaller ones enjoy higher annual growth rate; There exists a comparatively strong positive correlation in space in per capita carbon emission; urbanization, and total population. GDP per capita and international trade are the main influencing factors of industrial carbon emissions; There are spatial spillover effects on international trade and urbanization of neighboring cities, which have a significant impact on local industrial carbon emissions.

Understanding the change of land space utilization efficiency with different functions and its coupling coordination: A case study of Urban Agglomeration in the Middle Reaches of the Yangtze River, China

Land spaces function in capacities of urban development,agricultural production,and ecological conservation,among many others.Research of land space utilization efficiency(LSUE)and coupling coordination relationships among its subsystems are significant for sustainable land space development.In this study,taking the Urban Agglomeration in the Middle Reaches of the Yangtze River(UAMRYR)as the study area,we establish a measurement index system to evaluate the LSUE(2000–2018)and analyze its coupling coordination degree by utilizing an improved coupling coordination model.The main results include the following.(1)The average efficiency levels of urban space and agricultural space in the UAMRYR increased 2000–2018,while the average efficiency of ecological space declined.(2)The spatial pattern of the LSUE values varied greatly,with the distributions of high-efficiency and low-efficiency levels significantly different.(3)The coupling degree of LSUE includes three types,i.e.,high-level coupling,break-in,and antagonism.Each coupling degree type was characterized by change over time.(4)The proportion of areas with high coupling coordination and moderate coupling coordination increased from 2000 to 2018,while the proportion of areas with basic coupling coordination,moderate imbalance,and serious imbalance declined during this period.Given that the spatial differentiation of the LSUE and its coupling coordination,it is necessary to implement a differential land space development strategy in the UAMRYR.This study is helpful to promote the efficient utilization and coordinated development of land space utilization systems.

Traffic accessibility and the coupling degree of ecosystem services supply and demand in the middle reaches of the Yangtze River urban agglomeration,China

The spatial relationships between traffic accessibility and supply and demand(S&D)of ecosystem services(ESs)are essential for the formulation of ecological compensation policies and ESs regulation.In this study,an ESs matrix and coupling analysis method were used to assess ESs S&D based on land-use data for 2000,2010,and 2020,and spatial regression models were used to analyze the correlated impacts of traffic accessibility.The results showed that the ESs supply and balance index in the middle reaches of the Yangtze River urban agglomeration(MRYRUA)continuously decreased,while the demand index increased from 2000 to 2020.The Gini coefficients of these indices continued to increase but did not exceed the warning value(0.4).The coupling degree of ESs S&D continued to increase,and its spatial distribution patterns were similar to that of the ESs demand index,with significantly higher values in the plains than in the montane areas,contrasting with those of the ESs supply index.The results of global bivariate Moran’s I analysis showed a significant spatial dependence between traffic accessibility and the degree of coupling between ESs S&D;the spatial regression results showed that an increase in traffic accessibility promoted the coupling degree.The present results provide a new perspective on the relationship between traffic accessibility and the coupling degree of ESs S&D,representing a case study for similar future research in other regions,and a reference for policy creation based on the matching between ESs S&D in the MRYRUA.

长江中游城市群交通一体化建设存在的问题与推进建议

交通一体化能促进生产要素高效流动与整合,有力推动区域经济与社会一体化发展和经济内循环顺利实现。长江中游城市群在交通一体化方面取得很大进展,不仅建立完备的由铁路、公路、地铁、航空、水运等运输方式组成的综合交通运输网络,而且在交通管理与服务方面实现一定程度的信息化与智能化。但长江中游城市群交通一体化建设存在政府与市场配合度不高,缺乏统一的跨区域整体规划和协调机制,各种交通方式互联互通效率低下,智能交通建设落后等困难与问题。可以通过提高政府一体化建设积极性与市场参与度,破除行政壁垒,建立一体化管理协调机制,发展多式联运促进互联互通,增强交通管理与服务的信息化和智能化建设等,进一步推进长江中游城市群交通一体化建设,以服务区域经济内循环和城市群的整体发展。

长江中下游城市内涝与雨季污染协同治理对策

针对长江中下游城市内涝与雨季污染协同治理的突出问题,对城市水安全、雨季水体返黑返臭风险和河湖水生态退化三方面存在的问题进行了论述。发现长江中下游城市河网密度高、降水量大、暴雨多发,同时人口密集、经济发展水平高,内涝、污染、生态退化等水问题突出;城市内涝频发,雨季污染造成某些城市水体局部返黑返臭,严重影响城市水环境品质,成为制约长江中下游城市绿色发展的重要瓶颈问题。提出了建立三级内涝协同防治体系、构建城市“绿-灰-蓝”设施耦合工程体系、协同推进水体品质提升与生态修复等建议。

长三角城市群物流业高质量发展水平测度研究及评价

以长三角城市群物流业为研究对象,采用熵权TOPSIS法和核密度估计分析方法,测度2010—2021年长三角城市群物流业高质量发展水平并分析区域发展差异。研究发现:长三角城市群物流业高质量发展水平向好趋势明显,但仍然有待提高。有18个城市的物流业高质量发展水平低于均值。其中上海的物流业高质量发展水平最高,居于第2位的苏州相比于上海还有较大差距。从各区域来看,区域发展不均衡的特征较明显,各区域物流业高质量发展水平存在一定差距,上海物流业高质量发展水平显著高于其他区域,物流业高质量发展水平排名靠后的城市主要集中在安徽,该区域内发展差距呈现缩小趋势。

长三角城市群A级旅游景区时空异质性研究

城市群A级旅游景区演化研究对促进区域旅游业平衡充分发展具有重要价值.基于目的地多尺度、景区多等级及空间非稳定现实,运用多种空间分析方法,对长三角城市群A级旅游景区及影响因素的时空异质性进行研究.结果表明:(1)2001-2021年,3A、4A是长三角城市群A级旅游景区结构主体;上海、杭州、湖州、南京、安庆、金华、温州和台州的各级景区发展均较好.(2)长三角城市群A级旅游景区空间分布集聚性显著,逐渐形成“几”字形高密度景区带结构;各等级景区辐射范围不断扩大,形成东南-西北方向分布格局;城市尺度上,各等级景区都趋于均匀分布.(3)至2019年,影响A级旅游景区空间分布的因素包括旅游资源、旅游需求、旅游地交通及社会经济条件.各个因素的影响程度及其在空间上的异质性均随时间变化而变化.

长江中游城市群城市土地利用效率及影响因素——基于非预期超效率SBM模型和空间计量分析

本文以长江中游城市群36个地级市为研究对象,基于2000-2019年统计数据,运用非预期超效率SBM模型,综合计算评估长江中游城市群的土地利用效率和效率分解,并构建空间杜宾模型分析其影响因素。研究结果表明,长江中游城市群土地利用效率并没有实现联动发展,湖北省在地区土地利用中独自领先,湖南省和江西省既没有在内部形成聚集,且与湖北省及其周边城市也缺乏联动。在空间杜宾计量模型分析中,外溢性较小的地区发展因素对土地利用效率推动最大,间接反映出长江中游城市群内部省际要素流动不太通畅,土地利用效率具有高度自我强化特性,现有高效利用的土地会进一步强化土地后续的高效率配置。

逆全球化背景下区域协同创新网络抗毁性评价——以长江经济带城市群为例

从结构抗毁性和功能抗毁性两个维度构建区域协同创新网络抗毁性评价指标体系,进而提出改进的AHPCRITIC组合赋权法确定指标权重,并采用TOPSIS方法对长江经济带3个城市群协同创新网络的抗毁性水平进行综合评价。结果表明,长三角城市群的协同创新网络抗毁性水平最强,成渝城市群次之,中游城市群最低;随着时间推移,长三角城市群的抗毁性持续增强,成渝城市群呈现“V”型减弱趋势,中游城市群呈现“V”型增强趋势;从结构抗毁性看,长三角城市群持续增强,成渝城市群与中游城市群呈现“V”型增强趋势但增幅较小;从功能抗毁性看,长三角城市群与中游城市群均呈现“V”型增强趋势,而成渝城市群呈现“V”型减弱趋势。

基于碳汇潜力的碳排放空间关联网络结构特征及影响因素——以长江中游城市群为例

考虑碳汇潜力的碳排放空间关联是促进城市群协同减排的重要基础,更是实现碳中和的有力抓手。以长江中游城市群为研究区,对传统引力模型进行修正,构建兼具碳汇潜力的碳排放空间关联网络,采用社会网络分析(SNA)和二次指派程序方法(QAP)探究长江中游城市群碳排放空间关联网络的时空特征与影响因素。结果表明:①研究期间长江中游城市群碳排放网络关联关系数、网络密度和网络关联度呈增长趋势,网络效率和网络等级度不断下降,且网络等级度在2010年后始终为0,表明碳排放空间关联网络日益稠密、网络通达性较强,存在多重叠加的溢出渠道,但等级结构并不森严。基于碳汇潜力的长江中游城市群碳排放空间关联网络从“双核化”向“多极化、多线程”网络形态发展,核心城市的扩散作用不断增强。此外,以抚州、宜昌、鹰潭、上饶和吉安等为代表的高碳生态承载力地区,在碳排放空间关联网络中的受益关联性大于溢出关联性。②2020年,长江中游城市群碳排放空间关联网络形成四大板块,相较于板块内部成员间的碳排放空间关联效应,板块间的碳排放空间关联效应更为明显,即板块间的“碳排放转移”效应较为普遍。净溢出板块主要分布在武汉都市圈、宜荆荆都市圈和长株潭城市群外围城市,处于网络核心圈层位置;净受益板块主要分布在环鄱阳湖城市群东部,“碳排放避难所”效应显著。经纪人板块集中在环鄱阳湖城市群西部,板块间表现出“净溢出板块→经纪人板块→净受益板块”的碳排放传递路径,呈现出明显的“梯度转移”特征。双向溢出板块主要位于长江中游城市群西部,对净溢出和净受益板块都存在碳排放的空间溢出。研究期内,净溢出板块的成员虽然有所变化但总数保持不变,经纪人板块的成员有所增加,而净受益和双向溢出板块的成员均减少,环鄱阳湖城市群的“碳排放避难所”效应有所弱化。③地理邻近关系能够促进城市间碳排放关联关系的建立,而城市间的经济集聚程度、土地利用强度和经济发展水平上的互补性,促使碳排放空间关联网络随着城市间分工与协作的加强而呈现出千里“碳缘”一线牵的特点。

长三角城市群基础设施与旅游经济耦合协调时空格局演变及驱动机制

以长三角城市群为研究对象,构设基础设施水平与旅游经济发展综合评价指标体系,采用耦合协调度模型探析二者耦合协调发展的时空演化特征,并运用地理探测器考察分析其驱动机制。结果表明:1)基础设施水平与旅游经济发展的综合评价指数、耦合协调度均呈稳步提升趋势,二者耦合协调类型介于中度协调与极度协调之间且较快地实现协调等级跃迁;耦合协调度省际差异显著,呈“上海市>江苏省>浙江省>安徽省”的空间异质性特征。2)耦合协调度呈“东高西低,中部高南北低”空间分布格局,且高、低耦合协调区分别呈空间“扩张-收敛”相背离的变化态势;考察期间基础设施滞后型城市数量逐渐增多,分布于长三角城市群东部浙沪地区;旅游经济发展滞后型城市分布范围逐渐收敛并向长三角北部聚集。3)基础设施水平与旅游经济发展耦合协调性主要受经济拉动力、政府调控力、城市化带动力作用,二者协调发展由8项驱动力形成的经济运行与结构转型机制、政策调控与开放合作机制、人口集聚与消费拉动机制、人才保障与科技创新机制综合驱动。

长江中游城市群创新网络演化及影响因素研究

区域一体化背景下,城市群成为推动区域创新协调发展的重要空间载体和增长极,创新活动由单一合作向网络化创新发展。研究利用长江中游城市群28个城市的发明专利合作数据构建创新网络,采用社会网络分析和QAP回归分析对2008—2019年长江中游城市群创新网络的演化进程和驱动机制进行了分析。研究表明:创新网络的规模持续扩张,创新联系增长迅速,创新网络结构从以武汉、长沙为中心的“双核心”结构发展为以武汉、长沙、南昌为中心的“三核心”结构;QAP回归分析发现,地理邻近性、制度邻近性、组织邻近性和地理邻近性对创新网络有显著的推动作用,产业邻近性对创新网络表现出抑制性。

产业空间关联网络对城市群经济韧性的影响——基于长江中游城市群数据的实证分析

近年来,国内外各式冲击频繁加剧,各区域所面临的内外部环境不确定性与日俱增,因而提高经济系统的抵御、调整和转型能力,即增强经济韧性成为把握新发展阶段、贯彻新发展理念和构建新发展格局的题中之义。选取长江中游城市群内27个主要城市为研究对象,应用改进的引力模型构建2010—2019年长江中游城市群产业空间关联网络,并从社会网络分析的角度测算产业空间关联网络中心度特征,实证检验长江中游城市群产业空间关联网络的三大中心度特征对城市群经济韧性的影响。结果表明:产业空间关联促进了城市群经济韧性的提升,并且在金融环境好、市场化程度高的城市以及非工业城市中,产业空间关联对经济韧性的提升作用更加显著。进而提出有助于长江中游城市群产业高质量发展、经济韧性水平攀升的政策建议。

An economic tie network-structure analysis of urban agglomeration in the middle reaches of Changjiang River based on SNA

Due to its great strategic significance in integrating regional coordinated development and enhancing the rise of Central China, urban agglomeration in the middle reaches of Changjiang （Yangtze） River has attracted much attention from both theoretical and practical aspects. Such research into the area＇s economic network structure is beneficial for the formation of an urban- and regional-development strategy. This paper constructs an economic tie model based on a modified gravitation model. Subsequently, referring to social network analysis, the paper empirically studies the network density, network centrality, subgroups and structural holes of the middle reaches of Changjiang River＇s urban agglomeration economic network. The findings are fourfold： （1） an economic network of urban agglomeration in the middle reaches of Changjiang River has been formed, and economic ties between the cities in this network are comparatively dense; （2） the urban agglomeration in the middle reaches of Changjiang River can be divided into four significant subgroups, with each subgroup having its own obvious economic communications, while there is less economic-behavioral heterogeneity among subgroups - this is especially true for the two subgroups that exist in the Poyang Lake Ecological Economic Zone; （3） an economy pattern driven by the central cities of Wuhan, Changsha and Nanchang has emerged in the urban agglomeration of the middle reaches of Changjiang River, while these three capital cities have exerted great radiation abilities to their surrounding cities, the latter are less able to absorb resources from the former （4） the Wuhan Metropolitan Areas and the Poyang Lake Ecological Economic Zone have more structural holes than the Ring of Changsha, Zhuzhou and the Xiangtan City Clusters, meaning that cities at the periphery of these two areas are easily constrained by central cities. The Ring of Changsha, Zhuzhou and the Xiangtan City Clusters have fewer structural holes; thus, the cities in this area will not face as many constraints as those in the other two areas.

金融集聚与城市绿色发展的时空耦合分析——以长三角城市群为例

基于2011-2021年长三角27个城市的面板数据,利用区位熵和超效率SBM模型测算长三角各城市金融集聚和城市绿色发展水平,构建两系统耦合协调度模型,分析两系统之间时空耦合特征。结果表明,长三角城市群金融集聚水平呈稳定上升态势,且差距逐渐缩小;城市绿色发展水平空间分布不均衡,随时间推移城市间差距愈发显著;两系统之间呈现高耦合、低协调的局面,形成了以上海、南京、杭州、合肥为高值中心,由高到低向四周扩散的发展格局,两系统协调值差异呈现先减后增的“U”型的趋势,且差异愈发明显。因此,需要加强长三角中心城市与周边城市信息互通,充分发挥中心城市的空间溢出效应带动周边区域发展,进而推动长三角城市群两系统协调发展。

基于DPSIR模型的城市旅游经济韧性评价与影响因素——以长三角城市群为例

基于DPSIR模型构建旅游经济韧性指标体系,对2009—2021年长三角城市群旅游经济韧性水平进行测度,并分析其演化特征与影响因素,以期为旅游经济韧性提升提供一定决策依据.结果表明:长三角城市群旅游经济韧性呈现“先升后降”的变化趋势,各城市韧性水平整体上呈上升趋势.韧性较高城市主要分布在中东部地区,各城市旅游经济韧性水平间具有一定空间集聚特征.旅游经济韧性受经济发展水平、经济发展结构、旅游发展速度、游客承载量、教育水平、基础设施和政府干预等因素的综合影响,其中旅游发展速度对旅游经济韧性具有明显负面影响,其他因素均具有显著促进作用.

旅游产业集聚与旅游生态安全的互动关系研究——以长江中游城市群为例

系统审视旅游产业集聚与旅游生态安全的互动关系对促进旅游高质量发展与生态可持续性发展具有重要意义。以长江中游城市群的26个城市为研究对象,基于区位熵和模糊物元模型分别测度2010—2021年各城市旅游产业集聚水平和旅游生态安全,并运用PVAR模型探讨旅游产业集聚与旅游生态安全的互动关系。研究结果表明:时间序列上,长江中游城市群旅游产业集聚水平和旅游生态安全整体呈现稳步上升的态势,旅游产业集聚水平的区域差异随时间变化不断提升,而旅游生态安全的区域差异则不断下降。空间分布上,长江中游城市群旅游产业集聚中高水平区占据主导地位,呈现出“环鄱阳湖城市群>环长株潭城市群>武汉城市圈”的格局;旅游生态安全呈现出以武汉市、南昌市与长沙市为主的“三足鼎立”的分布格局。长江中游城市群旅游产业集聚和旅游生态安全存在显著的互促关系,方差分解结果表明,旅游产业集聚和旅游生态安全受自身影响最大,且旅游产业集聚对旅游生态安全的影响远大于旅游生态安全对旅游产业集聚的影响。

长三角城市群FDI、技术创新与先进制造业集群发展

FDI和技术创新是长三角城市群先进制造业集群发展的重要影响因素。文章基于2010—2021年长三角城市群26个城市面板数据,分析FDI对先进制造业集群发展的直接作用机制以及技术创新在FDI与先进制造业集群发展之间的中介作用机制,并运用面板回归模型和中介效应模型检验理论假设。研究结果表明:长三角城市群FDI对先进制造业集群发展具有显著的正向作用,其作用机制主要表现为促进集群网络化、产业链优化和劳动力流动;技术创新在FDI与先进制造业集群发展之间具有显著的中介作用。根据研究结论提出长三角城市群促进FDI高质量发展、提高先进制造业集群的科技创新能力、加强FDI与技术创新的协同效应等政策建议。