The measurement of high-quality economic development level in the Yangtze River Economic Belt, along with an examination of its distribution dynamics, transfer characteristics, regional disparities, spatial agglomeration and obstacle factors, holds significant practical implications for establishing exemplary models of regional economic development and constructing a pilot demonstration zone for high-quality economic development in China. Based on fundamental data from 102 cities in the Yangtze River Economic Belt spanning from 2011 to 2020, this study constructs an evaluation index system for high-quality economic development. The level of high-quality economic development is measured through a comprehensive utilization of vertical and horizontal scatter degree method, fixed base efficiency coefficient method, and linear weighting method. Building upon this foundation, systematic analysis is conducted employing kernel density estimation, Markov chain estimation, Dagum Gini coefficient, Arcgis mapping technique, spatial Moran’s index, Moran scatter plot as well as obstacle factor diagnosis. The findings are as follows: (1) The level of high-quality economic development in the Yangtze River Economic Belt has steadily improved during the study period, with significant variations observed among provinces and cities. The regional development gap underwent an initial expansion followed by a subsequent narrowing, leading to a transformation from a pattern of multi-level differentiated gradient development to one of polarization, while also witnessing the emergence of a trend towards balanced development. (2)There is a high probability that each city will maintain its current level of development, confirming the phenomenon of solidification at high-level cities. (3)The regional gap primarily stems from inter-regional disparities and has shown a decreasing trend over the years. (4)High-quality development exhibits both high agglomeration and low agglomeration spatial characteristics, with significant radiation effects from higher-level cities. (5)The per capita utilization of foreign capital, residents' living standards, the level of marketization, and the rationalization of industrial structure are key determinants influencing the high-quality economic development in the Yangtze River Economic Belt. Additionally, factors such as unemployment rate, per capita participation in pension insurance, and energy efficiency also pose significant challenges to enhancing the level of high-quality economic development in certain provinces and cities.

This research focuses on the manufacturing industry and its sub-sectors in 11 provinces within the Yangtze River Economic Belt from 2003 to 2019.The paper utilizes the Super Efficiency SBM model to calculate the carbon emission efficiency.It comprehensively analyzes the dynamic evolution, spatial differentiation, and industry distribution characteristics.Finally, a spatial econometric model is introduced to systematically analyze the convergence characteristics of carbon emission efficiency in various regions.The research reveals the following findings: (1) The carbon emission efficiency of the manufacturing industry continued to improve, and the regional differences in carbon emission efficiency in the upper and middle reaches showed a decreasing trend, and the carbon emission efficiency of the overall Yangtze River Economic Belt and the downstream regions showed a significant polarization; (2) The carbon emission efficiency of the manufacturing industry showed a decreasing distribution of "downstream, midstream and upstream", and the distribution of carbon emission efficiency of the high-carbon manufacturing industry showed spatial heterogeneity.(3) Convergence characteristics are observed in the overall and downstream regions of the Yangtze River Economic Belt.The upstream and midstream regions show no σ-convergence but exhibit absolute β-convergence and conditional β-convergence.The impact of economic level, industrial structure, foreign direct investment level, urbanization rate, and green technological innovation on the change rate of urban carbon emission efficiency has significant heterogeneity. The main paths to enhance carbon emission efficiency in the manufacturing industry include optimizing regional collaboration and productivity layout; promoting the high-end transformation of industrial structure; improving the level of green and low-carbon technology.

Improving the industrial ecologicalization level is an important measure for the Yangtze River Economic Belt (YREB) to implement the strategy of “step up conservation and stop over development” and take the road of “ecological priority and green development”. Based on the connotation and characteristics of industrial ecologicalization, the evaluation index system of municipal industrial ecologicalization level was established in this study. In addition, the overall entropy method, exploratory spatial analysis method and spatial econometric model were used to dynamically evaluate the industrial ecologicalization level and analyzed its spatial-temporal evolution characteristics and the associated influencing factors. A total of 108 prefecture-level cities were selected in this paper in the YREB from the period of “11th Five-Year Plan” to “13th Five-Year Plan” (2006-2020). The findings were as follows: (1) The overall industrial ecologicalization level in the YREB increased year by year. The score rose from 0.374 in 2006 to 0.505 in 2020, with an average annual growth rate of 2.17%. (2) Regional differences of the industrial ecologicalization level in the YREB were apparent, showing a spatial differentiation pattern of “high in the east and low in the west” as a whole, with the features of hierarchical and stage evolution. (3) The industrial ecologicalization level in the YREB demonstrated significant spatial correlation characteristics. The high-high agglomeration areas were all distributed in the downstream cities, while the low-low agglomeration areas were scattered in the midstream or upstream cities. (4) Economic development, industrial upgrading, government regulation and urbanization could promote the improvement of the industrial ecologicalization level of city itself, while the industrial structure and environmental regulations would inhibit the level. (5) Under the indirect effect, economic development, industrial upgrading, industrial structure and technological innovation might promote the improvement of the industrial ecologicalization level of neighboring cities, while government regulation and foreign investment would pose an effect of inhibition.

Abstract：Green development is crucial for the high-quality development of resource-based cities. This study proposed an evaluation system for green development efficiency（GDE）, using the Theil index, panel quantile regression model, Geodetector to measure GDE in the Yangtze River Economic Belt（YREB）from 2001 to 2021. The spatiotemporal heterogeneity characteristics and associated driving factors as well as their interaction effect were analyzed. We concluded that:(1) The 38 resource-based cities in the YREB all exhibited an M-shaped trend; The upstream resource cities' GDE was marginally higher than that of the middle and downstream resource cities; The growing resource cities' GDE was lower than that of the other three types of cities; (2) The GDE of resource-based cities in YREB tended to have the normal distribution in quantity, resulting in a severe imbalance. The primary cause for the disparity in GDE was the alteration of upstream resource-based cities; (3) The degree of openness to the outside world, the amount of scientific and technological inputs, population density, and the amount of educational inputs contributed largely to the increasing GDE. We concluded that the two driving mechanisms were the “population-economic outward orientation-education” and “population-economic outward orientation-education-technology”, and the two restricting mechanisms were the “economy-transportation-pollution” and “economy-transportation-resources”; (4) Population density had the best interaction effect with the degree of opening to the outside world and the intensity of scientific and technological input. We should focus on the coordinated development of multi-factors, and strengthen the synergistic inter-regional governance to provide a scientific basis for improving the GDE of various resource-based cities in the YREB.

The Yangtze River Delta (YRD) has the industrial endowment to give full play to the kinetic energy of strategic emerging industries and high-tech industries, and has industrial, technological and market foundations for accelerating the formation of new productive forces. Relevant data of YRD cities were selected from 2016-2022, and the new productive forces of YRD cities were evaluated and analysed by CRITIC-Mutation Level Method-TOPSIS, Dagum Gini Coefficient and Obstacle Degree Model. The findings were as follows: (1) The average annual growth rate of new productive forces in the YRD region was 3.05%. The rate was ordered as Shanghai>Jiangsu> Zhejiang>Anhui, with Nanjing, Suzhou, Wuxi, Changzhou, Hangzhou and Hefei at the forefront of the region; (2) The Gini coefficient between provinces ranged from 0.14 to 0.18, which was at the absolute average level. There was a tendency of expanding for the contribution rate of intra-group differences and hyperintensity; (3) Among the system-level obstacle factors, human capital structure, material and intangible means of production had a greater influence on the new productive forces in the YRD as a whole and in each region. Based on the results of the study, relevant recommendations on intercity linkages and human capital structure were proposed to provide a basis for regional development.

Comparing the characteristics of industrial spatial organization of mature and growing metropolitan areas and identifying their formation mechanisms can help summarize the universal laws of industrial spatial organization in metropolitan areas, and provide a basis for optimizing industrial spatial organization in growing metropolitan areas. Taking the Shanghai metropolitan area and the Wuhan metropolitan area as examples, this study adopted the logic of comparative study to identify the common patterns and differences of industrial spatial organization in spatial agglomeration, functional collaboration and formation mechanisms of the two metropolitan areas. The results showed that in terms of spatial agglomeration characteristics, the Shanghai metropolitan area presented a gradient configuration of industrial chain division pattern; The Wuhan metropolitan area presented a near-regional organization, with a strong manufacturing links, a weak R&D and service link, and links in the industry chain were synergistically clustered in the near-region circle; It was found that a distance of 10 km was the key distance node for the combination of production and innovation factors of the two metropolitan areas, but the outer circle of Wuhan metropolitan area lacked the support of innovation factors. In terms of functional collaboration characteristics, the Shanghai metropolitan area were much stronger than the Wuhan metropolitan area in terms of network capacity, density and cooperation efficiency. The Shanghai metropolitan area was a polycentric network with both neighboring organizations and leapfrog organizations t, while the Wuhan metropolitan area was a single-center network with neighboring organizations; The near-circle organization of supply chain was a common feature of the two metropolitan areas, but the supplier self-sufficiency rate of the Wuhan metropolitan area was low. Finally, based on the comparative results and mechanism analysis of the characteristics of industrial spatial organization, this study put forward corresponding suggestions for the optimization organization of industrial space in growing metropolitan area from the perspective of core strengthening, functional collaboration innovation-driven and strengthening the sub-nucleus.

Soil organic carbon (SOC) is a key participant in carbon cycling within ecosystems and a bearer of soil ecological functions.It plays a crucial role in maintaining regional ecological balance and sustainable land use.The ecosystem in karst areas is extremely fragile, and the soil organic carbon (SOC) content exhibits significant variability both horizontally and vertically, which limits the implementation of effective ecological protection and land management measures.This study focused on soils of three common land use types, including cultivated land, forest land, and grassland within the karst landform of Lujiang river basin.We analyzed the variations in SOC content across the 0~100 cm soil profiles and investigated the potential soil physicochemical properties that impacted SOC content.The results indicated: (1)SOC content decreased with an increasing soil depth under all land use types.The grassland and forest land consistently exhibited significantly higher SOC content than the cultivated land; (2)CaO, MgO, Total nitrogen (TN), pH, and alkaline nitrogen exhibited significant positive correlations with SOC content for all land use types, while SiO2 showed a significant negative correlation; (3) The random forest model further identified that CaO, and alkaline nitrogen were the key factors influencing SOC content.In summary, there was considerable variability in SOC content in the karst landscape, with grassland and forest land exhibited significantly higher SOC levels than cultivated land.CaO, and alkaline nitrogen were identified as crucial soil physicochemical indicators that affected SOC content

As an accelerator and stabilizer of economy growth in China, the digital economy plays a crucial role in realizing the "dual-carbon" policy objectives.Based the balanced panel data from 26 cities in the Yangtze River Delta from 2011 to 2019, this paper measures the level of digital economy development employing entropy weight method and empirically analyzes the relationship between digital economy development and urban carbon emissions intensity, as well as the underlying mechanisms employing two-way fixed effects and mediation effects model.The results indicate: (1) There exists an inverted "U-shaped" relationship between digital economy development and urban carbon emissions intensity, which remains valid after a series of robustness tests; (2) Mechanism analysis reveals a "U-shaped" relationship between urban digital economy development and industrial structure upgrading, with digital economy indirectly affecting urban carbon emissions intensity through its influence on industrial structure upgrading; (3) Before and after the turning point of the inverted "U-shaped" relationship between digital economy development and urban carbon emissions intensity, green innovation capability exhibits respectively a "masking effect" and a "mediation effect"; (4) The digital economy development of the cities with lower levels of economic development in the Yangtze River Delta tend to experience higher carbon emissions compared to cities with higher economic development levels.Additionally, the role of digital economy development in promoting carbon emission reduction is more pronounced in "smart city" pilot cities compared to non-pilot cities.Finally, based on the research findings, relevant policy recommendations are proposed, which hold significant implications for achieving green and low-carbon development in the digital economy era

Abstract：Urban decarbonization is a crucial strategy for achieving the "dual-carbon" goal and fostering sustainable development.Concurrently, the integration of financial technology and green finance constitutes a significant approach to advancing urban decarbonization.Based on established mechanism for the synergistic promotion of urban decarbonization by fintech and green finance, this study conducted a research by selecting 108 prefecture-level cities in the Yangtze River Economic Belt from 2010 to 2021.Utilizing a comprehensive application of the coupled coordination model, kernel density estimation, spatial autocorrelation analysis, and econometric model, we empirically analyzed the spatiotemporal evolution characteristics of the synergistic development of fintech and green finance and examined the mechanism of the impact on urban decarbonization.The results showed that: (1) The synergistic evolution of fintech and green finance within the study area progressed from minimal to moderate coordination, exhibiting "high-high" and "low-high" spatial clustering, and demonstrating a pronounced positive spatial autocorrelation.(2) The integrated advancement of fintech and green finance substantially enhanced urban decarbonization.This effect exhibited regional heterogeneity, which showed the most pronounced in the lower reaches, followed by the middle reaches, and least evident in the upper reaches.(3) Urban industrialization and green technological innovation exhibited both first-order and second-order threshold effects on the synergistic promotion of urban decarbonization, indicating an increasing marginal effect.Drawing on the aforementioned conclusions, we propose certain policy recommendations aiming at establishing a novel green financial system, creating a synergistic framework for urban decarbonization, fostering the advancement of new industrialization, and bolstering green technological innovation.

Abstract：In order to enhance the effectiveness of floating debris management in the reservoir area of hydro-power projects, we constructed a multivariate co-governance evolution game model incorporating upstream and downstream clearing points and regulators.We also analyzed the key factors required to achieve the collaborative strategy's equilibrium and combined this with the real situation of clearing debris in the Three Gorges Reservoir area.In addition, we used system dynamics to simulate and optimize the game, revealing the evolution of the strategy for floating debris management.The study revealed that: (1) The improvement of the willingness of cross-border cooperation between upstream and downstream drifting points could alleviate the pressure of government supervision, and indirectly promoted the achievement of a balanced governance of drifting point cooperation.Simultaneously, the changes in their willingness to cooperate were synchronized, and the willingness of the downstream clearing points in the basin to manage the drifting debris was more influenced by the behavioral choices of the upstream points.(2) The local government could keep the upstream and downstream clearing points from becoming local interest conflicts by enforcing strict rules for rewards and punishments and ensuringthat everyone who worked together could get a fair share of the benefits.This was based on a thorough analysis of clearing capacity and other factors.(3) Reasonable clearing capital input and a differentiated subsidy strategy from the project owner could effectively resolve the mutual blame between the government and the enterprise and could promote the cooperative governance of the clearing points.(4) Common interests of upstream and downstream clearing points might enhance the sense of trust among each other, which was a driving force to reach cross-border cooperative governance.

Implementing watershed ecological compensation is an important measure to implement ecological protection rights and responsibilities to stimulate the enthusiasm of all parties to participate in watershed ecological protection.This is also an important content of the construction of ecological civilization system\[32\].Guizhou is located in an important ecological barrier area in the upper reaches of the Yangtze River and the Pearl River.Portraying the "water article" for ecological compensation in the river basin is a strong support for Guizhou to upgrade from a "pilot area" to a "pilot area".To promote the application of ecological product value accounting results in the construction of ecological compensation mechanisms, a watershed ecological compensation evaluation system was constructed, which consisted of three primary indicators of water resources products, aquatic ecological products, and aquatic environmental products,which referred to as "three water".A total of 11 secondary indicators was constructed and quantitatively calculated.The ecological product value of the study area was estimated from 2017 to 2021 after the completion of the watershed ecological compensation pilot.The results indicated that the implementation of the watershed ecological compensation policy had effectively stimulated the growth of the ecological product value of the "three waters" in Guizhou Province.In 2021, the value was 1297712 trillion yuan, an increase of 1963% compared to that in 2017.The implementation of watershed ecological compensation had significantly improved the water ecological environment, which played an important role in aspects of promoting the protection and utilization of water resources, improving water environment quality, and ensuring water ecological security