Analysis of factors influencing carbon emissions in the Yangtze River Delta region and projections of carbon peak scenarios

Based on the supply-side perspective,the improved STIRPAT model is applied to reveal the mechanisms of supply-side factors such as human,capital,technology,industrial synergy,institutions and economic growth on carbon emissions in the Yangtze River Delta(YRD)through path analysis,and to forecast carbon emissions in the YRD from the baseline scenario,factor regulation scenario and integrated scenario to reach the peak.The results show that:(1)Jiangsu's high carbon emission pattern is the main reason for the YRD hindering the synergistic regulation of carbon emissions.(2)Human factors,institutional factors and economic growth factors can all contribute to carbon emissions in the YRD region,while technological and industrial factors can generally suppress carbon emissions in the YRD region.(3)Under the capital regulation scenario,the YRD region has the highest level of carbon emission synergy,with Jiangsu reaching its peak five years earlier.Under the balanced regulation scenario,the YRD region as a whole,Jiangsu,Zhejiang and Anhui reach the peak as scheduled.

Land Use Dynamics and Ecosystem Service Value Changes in the Yangtze River Delta Urban Agglomeration Under Different Scenarios

Urban agglomerations,serving as pivotal centers of human activity,undergo swift alterations in ecosystem services prompted by shifts in land utilization.Strengthening the monitoring of ecosystem services in present and future urban agglomerations contributes to the rational planning of these areas and enhances the well-being of their inhabitants.Here,we analyzed land use conversion in the Yangtze River Delta(YRD)urban agglomeration during 1990-2020 and discussed the spatiotemporal response and main drivers of changes in ecosystem service value(ESV).By considering the different development strategic directions described in land use planning policies,we predicted land use conversion and its impact on ESV using the Future Land Use Simulation(FLUS)model in three scenari-os in 2025 and 2030.Results show that:1)from 1990 to 2020,land use change is mainly manifested as the continuous expansion of con-struction land to cultivated land.Among the reduced cultivated land,82.2%were occupied by construction land.2)The land use types conversion caused a loss of 21.85 billion yuan(RMB)in ESV during 1990-2020.Moreover,the large reduction of cultivated land area led to the continuous decline of food production value,accounting for 13%of the total ESV loss.3)From 2020 to 2030,land use change will mainly focus on Yangzhou and Zhenjiang in central Jiangsu Province and Taizhou in southern Zhejiang Province.Under the BAU(natural development)and ED(cultivated land protection)scenarios,construction land expansion remains dominant.In contrast,under the EP(ecological protection)scenario,the areas of water bodies and forest land increase significantly.Among the different scenarios,ESV is highest in the EP scenario,making it the optimal solution for sustainable land use.It can be seen that the space use conflict among urban,agriculture and ecology is a key factor leading to ESV change in the urban agglomeration of Yangtze River Delta.There-fore,it is crucial to maintain spatial land use coordination.Our findings provide suggestions for scientific and rational land use planning for the urban agglomeration.

Structural Characteristics and Influencing Factors of Carbon Emission Spatial Association Network:A Case Study of Yangtze River Delta City Cluster,China

City cluster is an effective platform for encouraging regionally coordinated development.Coordinated reduction of carbon emissions within city cluster via the spatial association network between cities can help coordinate the regional carbon emission management,realize sustainable development,and assist China in achieving the carbon peaking and carbon neutrality goals.This paper applies the improved gravity model and social network analysis(SNA)to the study of spatial correlation of carbon emissions in city clusters and analyzes the structural characteristics of the spatial correlation network of carbon emissions in the Yangtze River Delta(YRD)city cluster in China and its influencing factors.The results demonstrate that:1)the spatial association of carbon emissions in the YRD city cluster exhibits a typical and complex multi-threaded network structure.The network association number and density show an upward trend,indicating closer spatial association between cities,but their values remain generally low.Meanwhile,the network hierarchy and network efficiency show a downward trend but remain high.2)The spatial association network of carbon emissions in the YRD city cluster shows an obvious‘core-edge’distribution pattern.The network is centered around Shanghai,Suzhou and Wuxi,all of which play the role of‘bridges’,while cities such as Zhoushan,Ma'anshan,Tongling and other cities characterized by the remote location,single transportation mode or lower economic level are positioned at the edge of the network.3)Geographic proximity,varying levels of economic development,different industrial structures,degrees of urbanization,levels of technological innovation,energy intensities and environmental regulation are important influencing factors on the spatial association of within the YRD city cluster.Finally,policy implications are provided from four aspects:government macro-control and market mechanism guidance,structural characteristics of the‘core-edge’network,reconfiguration and optimization of the spatial layout of the YRD city cluster,and the application of advanced technologies.

Does Foreign Direct Investment Affect S0_(2) Emissions in the Yangtze River Delta?A Spatial Econometric Analysis

As the major source of air pollution,sulfur dioxide(S0_(2))emissions have become the focus of global attention.However,existing studies rarely consider spatial effects when discussing the relationship between foreign direct investment(FDI)and S0_(2) emissions.This study took the Yangtze River Delta as the research area and used the spatial panel data of 26 cities in this region for 2004-2017.The study investigated the spatial agglomeration effects and dynamics at work in FDI and S0_(2) emissions by using global and local measures of spatial autocorrelation.Then,based on regression analysis using a results of traditional ordinary least squares(OLS)model and a spatial econometric model,the spatial Durbin model(SDM)with spatial-time effects was adopted to quantify the impact of FDI on S0_(2) emissions,so as to avoid the regression results bias caused by ignoring the spatial effects.The results revealed a significant spatial autocorrelation between FDI and S0_(2) emissions,both of which displayed obvious path dependence characteristics in their geographical distribution.A series of agglomeration regions were observed on the spatial scale.The estimation results of the SDM showed that FDI inflow promoted S0_(2) emissions,which supports the pollution haven hypothesis.The findings of this study are significant in the prevention and control of air pollution in the Yangtze River Delta.

Urban Land Use Efficiency and Contributing Factors in the Yangtze River Delta Under Increasing Environmental Restrictions in China

Evaluating urban land use efficiency(ULUE) provides insights into the interactions between land use systems and their external environment. Specifically, changes in ULUE are important for monitoring urban transformation in developing countries. In this study, using a traditional input-output index model, we incorporated slack-based measurements and undesirable outputs into a SBM-UN(slack-based measure-undesirable) model to investigate ULUE within the context of increasing environmental restrictions in China. The model was used to estimate the ULUE of 26 cities in the highly developed urban agglomeration of the Yangtze River Delta from 2000 to2018. The average ULUE in the Yangtze River Delta was relatively low compared to that of developed city regions in the European Union(EU) and North America and exhibited a U-shaped curve over the study period. Incorporating undesirable outputs, such as environmental pollution, into the model reduced ULUE by 19.06%. ULUE varied spatially, with the kernel density estimation exhibiting a bimodal distribution. Efficiency decomposition analysis showed that scale efficiency made a greater contribution to ULUE than pure technical efficiency. Based on our findings, recommended approaches to improve ULUE include optimizing factor allocation, reducing undesirable outputs, and increasing the effective output per land unit. The study suggests that ULUE and the SBM-UN model are useful planning tools for sustainable urban development.

Mapping Urban Networks through Inter-Firm Linkages: The Case of Listed Companies in Yangtze River Delta, China

Recently, literature on urban network research from the perspective of ?rm networks has been increasing. This research mainly used data from the headquarters and branches of all 2581 listed manufacturing companies in the Yangtze River Delta from 1990 to 2017, and studied the urban network through an interlocking network model that quantifies the links between enterprises. The results showed that the spatial distribution of listed manufacturing industries in the Yangtze River Delta was relatively concentrated, and cities such as Shanghai, Nanjing, and Hangzhou were hot spots for the spatial distribution of listed manufacturing industries. However, Fuyang, Suqian, Chizhou, Lishui and other network edge cities were less distributed in manufacturing. The urban network of the Yangtze River Delta has significant hierarchical characteristics. The urban network of the Yangtze River Delta presents a multi-center network development mode with Shanghai as the center and Nanjing, Hangzhou, and Hefei as the sub-centers. Moreover, we found that the development of inter-city connections in the Yangtze River Delta was driven by network mechanisms of priority attachment and path dependence. The radiating capacity and agglomeration capacity of cities in the Yangtze River Delta have a strong polarization characteristic. The core cities such as Shanghai, Nanjing, Hangzhou, and Hefei have much higher network radiation capabilities than network aggregation capabilities. However, other non-core cities and network edge cities have weak network radiation capabilities, and mainly accept network radiation from core cities. It enriches the research of urban networks based on real inter-?rm connections, and provides ideas for the wider regional study and the combination of econometric techniques and social network analysis.

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.

The Influence of the Urban-Rural Income Disparity on the Industrial Structure—Taking the Yangtze River Delta Region as an Example

In this paper, the effect of the mediation effect is mainly used to test and analyze the regression model, and most scholars have studied the impact of the modernization of the industrial structure on the income gap. However, this paper is from another perspective, based on the social background of high-quality development, the main study is the impact mechanism of urban and rural income gap on the industrial structure, taking the Yangtze River Delta as the main research object, and specifically selecting 22 central cities in the Yangtze River Delta region, which is also one of the highlights of this study. The regression model is constructed by using the intermediary effect, and the four intermediary variables of fiscal expenditure (M1), fixed asset investment (M2), number of patent applications (M3), and total import and export (M4) are selected, which represent the role of the government, fixed asset investment, scientific and technological level and opening-up level, and study and analyze the inherent influence mechanism between each variable. Before doing specific research, I consulted the papers and literature of many other outstanding scholars, among which Cheng Yuhong and Cheng Chi’s “The Influence Mechanism of industrial structure of urban and rural income gap” [1] has great reference value for this paper. According to the research results, under the background of high-quality development in the Yangtze River Delta region, the expansion of the income gap between urban and rural areas will inhibit the upgrading of the industrial structure, so it is necessary to focus on building a new type of urbanization, accelerating the construction of an urban innovation system, optimizing the rural employment structure to narrow the income gap between urban and rural areas, and providing impetus for the continuous upgrading of the industrial structure.

An Empirical Study on the Effectiveness of Technology Market Promoting Technological Innovation Capability—Based on panel data in the Yangtze River Delta

Based on panel data such as 2009-2018 R&D expenditures,full-time equivalent of R&D personnel,Number of valid invention patents,and technology market turnover in China's Shanghai,Jiangsu,Zhejiang,and Anhui provinces(cities),using Griliches-Jaffe knowledge to produce Function,construct Time fixed effects model,conduct empirical research on the main factors affecting the technological innovation capability of the Yangtze River Delta,focusing on the relationship between the technological market and technological innovation capability.The results show that human capital and R&D expenditures have a significant and positive impact on the technological innovation capacity of the Yangtze River Delta.Although the technology market has a positive effect on the scientific and technological innovation capacity of the Yangtze River Delta,the effect is not significant.Propose countermeasures and suggestions to strengthen the influence of the technology market on technological innovation.

The Impact of the Upgrading of Industrial Structure in the Yangtze River Delta on the Urban-Rural Income Gap

Firstly,this paper conducts theoretical analysis and current situation analysis,and then proposes research hypotheses.Secondly,using spatial Dubin model and partial differential method,it empirically studies the impact of industrial structure advancement and rationalization on the urban-rural income gap.The results show that:(1)Both industrial structure and urban-rural income gap have significant spatial dependence;(2)The increase in the industrial structure rationalization will narrow the urban-rural income gap in local region,while its spillover effect on neighboring areas is not obvious.(3)The impact of the industrial structure advancement on the urban-rural income gap is not linear.It is first expanded and then narrowed.The industrial structure advancement in the Yangtze River Delta will generally narrow the urban-rural income gap at this stage.Finally,this paper put forward relevant suggestions.

Efficiency Pattern and Spatial Strategy of Ports in Yangtze River Delta Region

This paper measures the efficiency of ports in the Yangtze River Delta Region(YRDR) in 2008 and 2013 using port berth quantity, quay length, and human resources as input indicators, using cargo and container throughput as output indicators, and considering traditional(foreign trade dependence and industrialization level) and modern environmental factors(traffic line density, financial development level, and informatization level). To achieve such aim, this study constructs a multi-stage data envelopment analysis model(DEA) that identifies effective port decision-making units(DMUs) and generates a highly accurate conclusion by eliminating the interference from the exogenous environment and random errors. First, the external environment significantly affects port efficiency, with the traditional environmental factors showing huge fluctuations and the modern environmental factors producing great benefits. Second, the efficiency of ports in YRDR has increased from 2008 to 2013 primarily because of their pure technical efficiency. Third, the weighted standard deviation ellipse(SDE) analysis results reveal that the efficiency pattern of ports significantly deviates from their throughput pattern, while the center of SDE of port efficiency moves from the eastern coastal regions to the northwest regions. Based on these findings, this paper proposes spatial development strategies for YRDR, such as creating an unblocked environment where spatial elements can freely circulate, intensifying port-city joint development, implementing differentiated policies, and focusing on the spatial collaboration of port efficiency.

Impacts of Roof/Ground Mitigation Strategies on Improving the Urban Thermal Environment and Human Comfort over the Yangtze River Delta, China

The combined effects of global warming and the urban heat islands exacerbate the risk of urban heat stress. It is crucial to implement effective cooling measures in urban areas to improve the comfort of the thermal environment. In this study, the Weather Research and Forecasting Model(WRF), coupled with a single-layer Urban Canopy Model(UCM), was used to study the impact of heat mitigation strategies. In addition, a 5-km resolution land-cover dataset for China(ChinaLC), which is based on satellite remote sensing data, was adjusted and used, and 18 groups of numerical experiments were designed, to increase the albedo and vegetation fraction of roof/ground parameters. The experiments were conducted for four heatwave events that occurred in the summer of 2013 in the Yangtze River Delta urban agglomeration of China. The simulated results demonstrated that, for the single roof/ground schemes, the mitigation effects were directly proportional to the albedo and greening. Among all the experimental schemes, the superposed schemes presented better cooling effects. For the ground greening scheme, with similar net radiation flux and latent heat flux, its storage heat was lower than that of the roof greening scheme, resulting in more energy flux into the atmosphere, and its daytime cooling effect was not as good as that of the roof greening scheme. In terms of human thermal comfort(HTC), the improvement achieved by the ground greening scheme was better than any other single roof/ground schemes, because the increase in the relative humidity was small. The comprehensive evaluation of the mitigation effects of different schemes on the thermal environment presented in this paper provides a theoretical basis for improving the urban environment through rational urban planning and construction.

长三角地区技术转移与成果转化效率分析——基于三阶段DEA模型分析

[目的/意义]研究技术转移与成果转化效率顺应时代发展要求,对于加强技术创新政策优化配置,催化科技成果真正转化为现实的生产力具有重要的理论意义和现实意义。[方法/过程]利用包括随机前沿分析在内的三阶段DEA方法,以长三角地区的江苏、上海、浙江和安徽四个省市作为研究对象,对其2015—2021年的技术转移与成果转化效率进行评价,并对比分析剔除环境因素和随机因素前后的效率值。[局限]研究样本较少,未考虑科技镇长团成员数等可能影响技术转移与成果转化的其他因素。[结果/结论]结果发现长三角四省市的技术转移与成果转化效率整体较高,其中服务环境、科技政策环境、经济发展环境和随机扰动是影响技术转移与成果转化效率的重要因素,通过第三阶段DEA分析发现,四省市的效率均值有所降低。根据上述研究结论,从合理规划技术转移与成果转化资源投入、健全科技成果转移转化机制等方面提出对策建议。

基于DEA-Tobit模型的长江经济带物流效率及其影响因素研究

文章基于2012—2021年长江经济带11个省市的物流业发展数据,采用DEA作为分析工具对长三角经济带物流效率进行实证研究,并在此基础上,利用Tobit模型探究各因素对物流效率的影响程度。研究结果显示,第一,长江经济带物流效率整体呈现上升趋势,但三大区域物流发展效率存在较为明显的不均衡现象,且下游地区较高,上中游地区相对滞后;第二,经济发展水平、产业结构、市场化程度和物流产业集聚能够有效促进长江经济带整体物流效率的提高,而人力资本水平不利于提高物流效率。根据研究结果,文章对长江经济带物流业发展提出相应的对策建议以促进物流行业区域协调发展。

城市群旅游生态效率时空演化及影响因素比较研究——以长三角与珠三角城市群为例

基于2009—2020年长三角城市群和珠三角城市群的城市面板数据,综合运用Super-SBM模型、非参数核密度估计、标准差椭圆等方法探讨旅游生态效率时空演化轨迹,并借助面板Tobit模型揭示其影响因素。结果表明:(1)城市群旅游生态效率时序演化具有阶段性特征。长三角城市群与珠三角城市群旅游生态效率均具有波动提升态势,前者核密度曲线呈现“单峰”向“双峰”演化以及峰距逐渐变窄的右移趋势,后者核密度曲线具有“多峰”向“双峰”演化以及右尾延展度变小的右移趋势。(2)城市群旅游生态效率具有空间异质性。长三角城市群旅游生态效率呈现东部沿海城市较高、中西部偏低的“高高集聚、低低集聚”空间分布格局,旅游生态效率重心呈东北—西南方向移动;珠三角城市群呈现以东部珠江入海口附近高、西部低的空间分布格局,旅游生态效率重心呈西北—东南方向移动。(3)城市群旅游生态效率影响因素具有综合性与差异性。经济发展、对外开放对长三角城市群旅游生态效率具有正向推动作用,产业结构与政府调控负向抑制作用明显;产业结构、科技创新与对外开放对珠三角城市群旅游生态效率正向推动作用较大,信息化水平呈负向抑制作用。

基于带偏好DEA模型的长株潭城市群公路交通效率评价

从城市群公路交通系统的输入和输出角度出发,给出城市群公路交通效率的输入输出指标体系,建立数据包络分析(data envelopment analysis,DEA)模型及带偏好DEA(A-prefer-DEA,PDEA)模型,进而对长株潭、长三角和珠三角城市群公路交通效率进行有效计算和综合评价.传统DEA模型的评价结果表明:长株潭城市群公路交通效率为DEA弱有效,长三角和珠三角公路交通效率为DEA有效;PDEA模型评价结果更直观,长三角、珠三角和长株潭公路交通效率值分别为1.678 2、1.577 9和0.866 2,长株潭公路交通效率与长三角和珠三角的差距比较明显.

基于DEA模型的城市群效率研究——珠三角城市群的实证研究

应用DEA模型,选取国内生产总值、城市建成区面积、固定资产投资额、从业人员人数、人口规模、产业结构和交通网络密度等指标,从城市经济发展水平的维度,通过对珠三角城市群与广东省其他非城市群城市以及和长三角城市群的比较分析,得出珠三角城市群效率较高,但仍有一些城市的效率有待提高,最后指出提高这些城市效率的关键所在。

基于多层感知机模型的长三角水稻种植区净生态系统碳通量模拟

中国长江三角洲地区(以下简称长三角地区)是典型的水稻种植区,其碳源汇对区域气候和环境具有重要影响。本文系统地分析了长三角地区净生态系统碳交换量(net ecosystem exchange,NEE)与各个气象因子之间的关系,发现NEE与太阳短波辐射的相关性最强,其次与湿度相关参量(饱和水汽压差、相对湿度)等呈现较强的相关性。同时,NEE与太阳辐射、气温、湿度因子、风速和摩擦速度的相关性呈现明显的昼夜变化。基于上述分析,本文利用NEE和气象观测数据构建了长三角水稻下垫面多层感知机(Multilayer perceptron,MLP)NEE模拟模型,评估了模型的模拟效果及其时空稳定性。构建的MLP模型能较好地拟合NEE,训练集模拟的NEE与观测值的相关系数达到0.88,均方根误差为5.34μmol·m^(-2)·s^(-1);MLP模型在模拟长三角水稻季NEE时表现良好,在东台和寿县站点的模拟NEE结果与观测值的相关系数均高于0.78,模型具有较好的时空稳定性;MLP模型模拟白天平均NEE的效果好于夜间平均NEE的效果。研究结果揭示了影响水稻碳循环的主要气象因子,为认识长三角水稻种植区碳循环时空分布特征提供支撑,对准确评估全球和区域碳通量具有重要意义。

长三角地区批发零售企业经营绩效的超效率DEA研究

根据2005年～2008年长三角地区不同投资主体和所有制的批发零售企业的从业人员数等5个投入指标和销售总额等5个产出指标数据,应用DEA和超效率DEA方法,对企业经营绩效进行综合评价和生产规模效益分析。结果表明:在不同投资主体的企业中,外资企业的经营绩效最好,港澳台资企业的经营绩效最差;在不同所有制的内资企业中,国有企业的经营绩效最好,私营企业次之,股份制企业最差;有40%的企业DEA有效,65%的企业处于规模效率递增状态,增加这些企业的投入量将有助于提升其经营绩效。

基于改进超效率DEA模型的长江经济带科技创新效率研究

为了揭示长江经济带11省市科技创新效率演变规律及其影响因素,基于PCA-SE-DEA组合模型,对全国和长江经济带科技创新效率进行测度,重点对长江经济带的科技创新效率进行收敛性检验和影响因素分析。研究表明:长江经济带科技创新效率略低于全国平均水平;长江上中下游省市科技创新效率的地区差异呈逐步扩大趋势;长江经济带科技创新效率较低省市的追赶效应尚不明显;地区产业结构优化升级对长江经济带科技创新效率的影响最为显著。由此提出,长江经济带需要统筹协调,建立协同协作机制,构建全流域创新创业生态系统,提高整体科技创新效率。