黄河流域与黄河所经地区在国家发展中具有极为重要的战略地位。2019年9月习近平总书记在郑州主持召开黄河流域生态保护和高质量发展座谈会上发表了重要讲话,具有重大战略意义。本文对黄河流域的综合治理与可持续发展形成了初步认识,指出新时代黄河流域全面深刻转型发展的任务仍然艰巨,需转变理念,持续推进能源清洁高效利用,因地制宜重点推进产业发展,不搞粗放式大开发,搞好资源耕地保护等方面应是推进黄河流域综合治理及保障可持续发展的重要举措,认为“黄河经济带”在全国经济层面上不存在,目前不适宜将“黄河三角洲”确定为国家战略。

The Yellow River Basin and the areas along the Yellow River play an important strategic role in national development. Xi Jinping, General Secretary of the CPC, delivered an important speech at the symposium on ecological protection and high-quality development of the Yellow River Basin in Zhengzhou, which is of great strategic significance. This paper gives a preliminary understanding of the comprehensive governance and the sustainable development of the Yellow River Basin. It points out that the task of the comprehensive and profound transformation and development of the Yellow River Basin in the new era is still arduous, and change of concept is required. Continuing to promote the clean and efficient use of energy, promoting industrial development in accordance with local conditions, preventing extensive development and protecting cultivated land resources should be regarded as important measures to strengthen the comprehensive management and guarantee the sustainable development of the Yellow River Basin. It is believed that the "Yellow River Economic Belt" does not exist at the national economic level, and it is not appropriate to identify "the Yellow River Delta" as a national strategy.

黄河流域是中国区域发展战略格局的重要支撑区以及国土生态安全的关键区域,也是国家重要的能源安全支撑区和粮食安全基地。但受区位条件、自然地理环境和资源禀赋等因素影响,该地区经济基础相对薄弱,以能源重化工为主的单一化产业体系加重了地区生态环境负担。本文在辨析黄河流域生态保护与高质量发展主要限制因素的基础上,分析了地区产业发展对生态环境本底、大气环境、水资源与水环境、生态功能的胁迫特征,总结了地区产业发展与生态环境保护的主要矛盾及需要把握的关系;提出实现黄河流域生态保护与高质量发展目标,必须处理好产业开发布局与流域生态环境安全格局稳定、重点区域产业发展与资源环境承载能力、重点突破与系统统筹的关系。为此,建议该地区应优化产业发展路径,积极推进以绿色循环为核心的新型工业化,提升产业发展层次;以地区资源环境约束促进能源基础原材料产业规模控制和效率提升;以资源环境承载力为基础优化产业空间布局,确定适宜的产业发展空间和生态保护红线,推进重点能源化工基地建设和城市群产业集聚区建设;加强能矿资源开发的生态空间管控与生态修复,实施一批区域性生态环境治理和修复工程。

The Yellow River Basin is a key area for China’s regional development strategy and national ecological security. However, affected by the location, physical environment, and resource endowments, the economic foundation of the region is relatively weak. It has formed an industrial system dominated by energy and heavy chemical industries, which greatly increased the regional ecological burden. The Yellow River Basin is facing the predicaments of weak economic foundation and weak development ability, the pressures of accelerating social and economic development and transformation of development mode, the contradictions between resource use and ecological protection and between industrial development and environmental carrying capacity, and the challenges of deteriorating local living environment. The core contents of ecological environment protection and high-quality development of the Yellow River Basin is to balance the relationship between resource use and environmental protection, the scale of development and the carrying capacity of resources and the environment, and the development of key areas and the protection of the total ecological security to ensure energy security, ecological security, food security, watershed security, and the health of human settlements. We suggest that the region should optimize the industrial development path, actively promote the new industrialization with green industrial development as its core, and improve the level of industrial development and resource and environmental efficiency; optimize the industrial space based on the resource and environmental carrying capacity, determine suitable industrial development space and ecological protection red line, promote the construction of key energy and chemical bases and the construction of industrial clusters in urban agglomerations, implement strict environmental access policies, and improve environmental control standards for industrial development; strengthen spatial control and ecological restoration of energy and mining development projects, and implement a series of regional ecological environment governance and restoration projects.

Ecological protection and high-quality development of the Yellow River Basin is one of the major national strategies, in which urban agglomeration and industrial transformation development are the intrinsic requirements and fundamental guarantees. Thus, revealing the path of the river basin scale urban agglomeration development and industrial transformation and upgrading is of great significance to guide the high-quality development of the Yellow River Basin. Therefore, this paper brings together scholars from the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Research Institute for Eco-civilization, Chinese Academy of Social Sciences, Yellow River Institute of Hydraulic Research, Capital University of Economics and Business, Peking University and Henan University, to discuss key issues on urban agglomeration and industrial transformation development in the Yellow River Basin from the perspectives of ecological protection, resource allocation, dynamic evolution, spatial structure, and integration and regulation. This paper aims to serve the major national stragety of ecological protection and high-quality development of the Yellow River Basin. The core views are as follows, regulating the relationship among water resources, urban agglomeration and industrial development is the key to promoting the coordination of industrial transformation and urban transformation, and the synchronized advances of economic transformation and social transformation;the analysis of the complex coupling and dynamic evolution mechanism of river basin ecological protection and high-quality development is of great significance for achieving high-quality development of the basin; it is an effective way to promote the high-quality development of the basin to reveal the evolution mechanism of typical urban agglomeration and industrial space and to construct the spatial integration target and mode of urban agglomeration and industrial transformation development; under the background of increasing uncertainty of trade caused by globalization and energy revolution, complex relationship between social economy and ecological environment, and the construction of a new development pattern of "dual circulation", the basin urgently needs a more comprehensive integrated regulation mechanism.

黄河流域整体处于工业化中期到后期的转型发展和区域经济的起飞发展阶段,大体处于集聚功能大于扩散效应的“虹吸效应”阶段和区内发展的激烈竞争时期。高质量的中/高速经济增长是黄河流域现代化进程和可持续发展的前提。在大致梳理流域（区域）高质量发展的内涵及其理论演变的基础上,本文探讨了黄河流域高质量发展的基本条件及其核心策略。域内高质量发展的基本条件表现为农业发展的多样性和脆弱性,流域经济联系的松散性,经济发展阶段性及其内部差异性的约束,外部投资和产业转移等动力不足的约束等。这决定了流域高质量发展必表现为长期性、多样性、竞争性、协同性甚至区域化的倾向。因此,黄河流域高质量发展需探索“弯道超车”的核心策略：①在智能社会和全球化浪潮中,谋高质量增长,即持续探寻域内适合国家需求和地方特色的新型产业转型发展模式,建构适合各地方的特色化产业集群/产业链,提升综合竞争力;②探寻同质前提下的协同新模式,谋划流域协同和寻求特色化的新型城镇化模式,包括适合各地的人口城镇化策略和城乡统筹模式,尤其是基于土地流转的乡村人口向河谷/川地/盆地、平原、城镇的持续迁移路径,提高劳动生产率,关注水资源和基础设施建设等问题;③实施“中心突破”的体制,寻求中心带动的流域空间重构,推动中心城市和城镇群的健康发展,促进高质量发展。黄河流域高质量发展是一个至少20~30年的长期探索过程。

The Yellow River Basin as a whole is in the mid- to late stage of industrial transformation and the rapid development stage of the regional economy. It is in general in the “siphon effect” stage where the agglomeration function is stronger than the diffusion effect, and in the period of intense competition in intraregional development. Medium/high-speed economic growth of high-quality is a prerequisite for the modernization and sustainable development of the Yellow River Basin. Based on a general analysis of the connotation and change of theories of high-quality development in the basin (region), this article explores the basic conditions and core strategies of high-quality development in the Yellow River Basin. The basic conditions of high-quality development are the local diversity and vulnerability of agricultural development, the loose nature of the economic links in the river basin, constraints from the stage of economic development and its internal differences, and lack of momentum of external investment and industrial transfer, among others. These particularities determine that the high-quality development of the river basin must manifest itself in a long-term, diverse, competitive, cooperative, and regional orientation. Therefore, the high-quality development of the Yellow River Basin needs to explore a core strategy of “overtaking by curves”: (1) With the development of smart society and globalization, the region should seek high-quality growth, that is, continue to explore new industrialization models in the region that are suitable for national needs and local characteristics, and build localized industrial clusters/chain to enhance comprehensive competitiveness; (2) Explore new models of synergy under the premise of homogeneity, plan river basin coordination and improve coordination mechanisms, and seek a new urbanization model of localization, including localized population urbanization strategy and urban-rural coordination model, especially the continued migration of rural population to river valleys/basins, plains, and towns based on land transfer. Improve labor productivity, paying attention to water resources and infrastructure construction, and so on; (3) Implement the “center breakthrough” system, seek the spatial reconstruction of the drainage basin led by the centers, promote the healthy development of central cities and urban agglomerations, and promote high-quality development. In general, the high-quality development of the Yellow River Basin is a long-term exploration process of at least 20-30 years.

促进产业转型升级,提升绿色全要素生产率是推进我国资源型城市高质量发展的关键。但是,产业转型升级能否提升绿色全要素生产率在学术界一直存在争论。以2003— 2018年中国116个地级资源型城市为对象,分析了产业转型升级与绿色全要素生产率提升的演化特征和互动关系。结果表明：（1）56.9%的资源型城市产业转型升级并不理想,处于产业结构高级化和合理化不同步或双低的状态;有57.8%的资源型城市绿色全要素生产率实现了正增长,但仍有一些资源型城市绿色全要素生产率增长缓慢,主要是因为技术效率未得到有效改善。（2）PVAR模型和脉冲响应估计结果表明,资源型城市绿色全要素生产率提升的滞后期对其自身的影响存在负向作用。同时,资源型城市长期的传导路径为绿色全要素生产率提升受到反映产业结构合理化的泰尔指数的负向冲击后,对产业结构高级化产生持续性的积极作用,之后,产业结构高级化不断对自身产生正向冲击作用。（3）通过方差分解预测可知,未来绿色全要素生产率提升、产业结构高级化与合理化仍主要依赖自身发展路径。产业结构高级化对绿色全要素生产率提升的解释力高于产业结构合理化的解释力。随着期数的增加,产业结构高级化与绿色全要素生产率提升的相互解释力逐渐上升。

Advancing industrial transformation and upgrading and improving green total factor productivity are the key to promoting the high-quality development of resource-based cities in China. However, whether industrial transformation and upgrading can improve green total factor productivity has been controversial in academic circles. Focusing on 116 prefecture-level resource-based cities in China from 2003 to 2018, this paper analyzes the evolutionary characteristics and interactive relationship between industrial transformation and upgrading and green total factor productivity improvement. The results are as follows: (1) 56.9% of resource-based cities have implemented unsatisfactory industrial transformation and upgrading, and are in unbalanced state or double-low state between advanced and industrial structure rationalizations; 57.8% of resource-based cities have achieved positive growth in green total factor productivity, but the average annual growth rates of green total factor productivity in some resource-based cities increased slowly due to unimproved technological inefficiency. (2) The estimation results of PVAR model and impulse response show that there exists a time lag in the negative impact of green total factor productivity improvement on itself. At the same time, the long-term impact transmission mechanism is that after receiving the negative impact from the Theil index, an indicator to reflect industrial structure rationalization, the green total factor productivity improvement has a continuous positive effect on the industrial structure advancement. Then industrial structure advancement continuously imposes a positive effect on itself. (3) According to the analysis of variance decomposition forecast, green total factor productivity improvement, as well as industrial structure advancement and rationalization are mainly dependent on their own development paths. It can be seen that the explanatory power of the industrial structure advancement for green total factor productivity improvement is higher than that of the industrial structure rationalization. With the increase of periods, the mutual explanatory powers of both industrial structure advancement and green total factor productivity improvement gradually increase.

This study explores the effect of land finance (LF) and producer services on green total factor productivity (GTFP) according to spatial and agglomeration economic theories. Then, based on the spatial Durbin model, we employ panel data of 283 Chinese cities at the prefecture level and above from 2003 to 2015 to estimate the effect of LF and producer services agglomeration on GTFP. We find that specialized agglomeration of producer services promotes the GTFP of the city and its neighboring cities. While diversified agglomeration is advantageous to the GTFP in the city, it significantly reduces in neighboring cities. LF not only improves the GTFP of the city and neighboring cities but also weakens the promotion effect of the specialized agglomeration of producer services on the GTFP of the city and surrounding cities. Furthermore, we find that there exists industry and regional heterogeneities of the effect.

As the world’s largest carbon emitter, China has been committed to carbon emission reduction and green development. Under the goal of “double carbon”, adjusting the industrial structure and promoting the development of producer services are regarded as effective emission reduction paths. In this paper, from the perspective of market entry of enterprises, we firstly investigate the transmission mechanism between market entry of enterprises and industrial agglomeration and summarize the carbon emission reduction mechanism of producer services. Based on the panel data of 110 prefecture-level cities in China’s Yangtze River Economic Belt (YREB) from 2003 to 2017, we analyze the impact of producer services on carbon emission reduction by using the dynamic spatial panel model. The empirical results show that China’s urban carbon dioxide emissions have noticeable spatial spillover effects and high emission club clustering characteristics and exhibit a noticeable snowball effect and leakage effect in time and space dimensions. The development of the producer services can effectively reduce carbon emission levels, effectively solving the dilemma of “stabilizing growth and promoting emission reduction”. Furthermore, there is an apparent synergistic effect between enterprises’ market entry and industrial agglomeration. The agglomeration of producer services can effectively promote the entry of innovative new enterprises, thus increasing the carbon emission reduction effect. However, due to resource mismatch and isomorphic development, this carbon emission reduction effect has apparent industrial heterogeneity and regional heterogeneity. Finally, this paper makes suggestions for optimizing regional industrial structure, strengthening inter-regional linkage cooperation, and promoting the advanced development of the producer services.

Although China has a high rate of economic development, it still faces the problems of unstable industrial structure, low industrial level, and large carbon emissions, which pose huge challenges to China’s sustainable development. China is working hard to develop producer services to achieve industrial transformation and reduce carbon emissions. In this context, there is an extremely urgent need to conduct academic research on changes in producer service agglomeration and carbon emissions. Whether the producer service industry has agglomeration characteristics, and whether the producer service industry affects carbon emissions through multiple paths, are issues worthy of attention. Therefore, this paper takes China as the research area, selects the provincial administrative unit as the research sample, and conducts research on these issues by using exploratory spatial data analysis methods and various spatial econometric models under the guidance of the relevant theories of new economic geography. Our research finds that producer services have significant spatial agglomeration characteristics, and they also have significant spatial differentiation patterns. In addition, the agglomeration of producer services can significantly promote the reduction of carbon emissions and can show obvious spillover effects. Finally, in response to the research conclusions of this paper, we also put forward countermeasures and suggestions from the perspective of the common development of producer service industry and manufacturing industry, hoping to promote China’s transformation from industrial economy to service economy, to maximize the use of producer service industry accumulated dividends.

基于非期望产出视角测度黄河流域城市生态效率，探讨2003—2017年黄河流域城市生态效率时空演化特征及资源禀赋的门槛效应。结果表明：① 黄河流域城市生态效率呈稳步上升态势，但全域和资源型城市表现出一定梯度效应，有两极分化现象；② 各城市生态效率总体呈东高西低、南高北低格局，并存在显著空间溢出效应，不同类型城市演化存在显著的时空惯性。③ 资源禀赋存在显著门槛效应，资源型城市生产性服务业集聚与生态效率呈“U”型关系，制造业集聚在跨过门槛值后会产生抑制作用，产业协同集聚则始终具有正向作用；非资源型城市资源禀赋会削弱生产性服务业集聚的促进作用，制造业集聚及产业协同集聚的影响跨过门槛值后不显著。

This article studies the urban ecological efficiency of the Yellow River Basin, and discusses the spatial-temporal evolution characteristics of urban ecological efficiency and the threshold effect in the Yellow River Basin from 2003 to 2017 based on the perspective of unexpected output. The results showed that: 1) The ecological efficiency of the Yellow River Basin cities increased steadily, but the whole region and resource-based cities showed a certain gradient effect, with polarization phenomenon. 2) The ecological efficiency of each city is higher in the east and lower in the west, higher in the south and lower in the north, and there is a significant spatial spillover effect. 3) Resource endowment has a significant threshold effect. For resource-based cities, the relationship between producer services agglomeration and ecological efficiency is U-shaped, manufacturing agglomeration will have inhibitory effect after crossing the threshold, and industrial collaborative agglomeration always has a positive effect. For non resource-based cities, resource endowment will weaken the promoting effect of producer services agglomeration, while the influence of manufacturing agglomeration and industrial collaborative agglomeration is not significant after crossing the threshold.

基于2005—2017年黄河流域61个地级市数据,构建了黄河流域绿色发展效率投入产出指标体系,并运用多种计量方法研究了黄河流域绿色发展效率时空格局特征与驱动因素。结果如下：① 黄河流域绿色发展效率的区域差距不断扩大,研究期限内绿色发展效率呈现出由“高效率小差距”向“低效率大差距”演进,说明黄河流域绿色发展效率的俱乐部收敛特征不断凸显。② 黄河流域绿色发展效率增长主要来源于规模效率的贡献,科学技术尚未发挥重要驱动作用。③ 研究期限内黄河流域绿色发展效率存在较为明显的空间依存关系,绿色发展效率水平相近的地区空间集聚现象显著。④ 黄河流域绿色发展效率空间分异性显著,高效率地区的东西分布、南北分布的地域差异性突出,集中表现在以城市群为载体呈集群式发展。最后采用Tobit回归模型具体分析了产业结构、经济发展、科学技术、政府调控与市场化水平对于黄河流域及上中下游地区绿色发展效率的作用强度与作用效果。

Based on the data of 61 prefecture-level cities in the Yellow River Basin from 2005 to 2017, this paper constructed the input-output index system of green development efficiency, and used various spatial econometric models to examine the spatio-temporal pattern characteristics and influencing factors of green development efficiency in the study area. The following conclusions can be drawn as follows. (1) The regional differences of green development efficiency are gradually widening, evolving from “small differences and high efficiency” to “large differences and low efficiency” totally, which indicates that the club convergence characteristics of green development efficiency are obvious. (2) Scale efficiency makes significant contribution to the growth of green development efficiency, showing that large-scale agglomeration and intensive development are still an important guarantee for the improvement of green development efficiency. However, science and technology have not yet played an important driving role in improving the green development efficiency. In the future, improving the level of science and technology in this basin is the key to optimizing and improving the green development efficiency. (3) There is an obvious spatial reliable correlation of green development efficiency within the study period, and the regional spatial agglomeration featured with similar green development efficiency level is significant. (4) The spatial distributions of green development efficiency are obviously diverse, and the regional differences between the east-west distribution and north-south distribution of high-efficiency areas are prominent, which mainly shows a cluster development stimulated with urban agglomeration. and reflects that the green development efficiency of the study basin has a circular cumulative path dependent effect. The influencing factors of green development efficiency in the Yellow River Basin can be attributed to the adjustment effect of industrial structure, the growth effect of economic development, the demonstration effect and spillover effect of science and technology, the government regulation mechanism and market-oriented mechanism. Finally, Tobit regression model is used to analyze the influencing intensity and direction of industrial structure, economic development, science and technology, government regulation and marketization level on green development efficiency in the Yellow River Basin and its subzones.

由CO₂排放所引起的气候变化是当今社会所关注的热点话题,提高碳排放绩效是碳减排的重要途径。目前关于碳排放绩效的研究多从国家尺度和行业尺度进行探讨,由于能源消耗统计数据有限,缺乏城市尺度的研究。基于遥感模拟反演的1992—2013年中国各城市碳排放数据,采用超效率SBM模型对城市碳排放绩效进行测定,构建马尔可夫和空间马尔可夫概率转移矩阵,首次从城市尺度探讨了中国碳排放绩效的时空动态演变特征,并预测其长期演变的趋势。研究表明,中国城市碳排放绩效均值呈现波动中稳定上升的趋势,但整体仍处于较低的水平,未来城市碳排放绩效仍具有较大的提升空间,节能减排潜力大;全国城市碳排放绩效空间格局呈现“南高北低”特征,城市间碳排放绩效水平的差异性显著;空间马尔科夫概率转移矩阵结果显示,中国城市碳排放绩效类型转移具有稳定性,且存在“俱乐部收敛”现象,地理背景在中国城市碳排放绩效类型转移过程中发挥重要作用;从长期演变的趋势预测来看,中国碳排放绩效未来演变较为乐观,碳排放绩效随时间的推移而逐步提升,碳排放绩效分布呈现向高值集中的趋势。因此未来中国应继续加大节能减排力度以提高城市碳排放绩效,实现国家节能减排目标;同时不同地理背景的邻域城市之间应建立完善的经济合作联动机制,以此提升城市碳排放绩效水平并追求经济增长与节能减排之间协调发展,从而实现低碳城市建设和可持续发展。

Climate change caused by CO2 emissions has become an environmental issue globally in recent years, and improving carbon emission performance is an important way to reduce carbon emissions. Although some scholars have discussed the carbon emission performance at the national scale and industry level, literature lacks studies at the city- level due to a limited availability of statistics on energy consumptions. In this study, based on China's city-level remote sensing carbon emissions from 1992 to 2013, we used the super-efficiency SBM model to measure the urban carbon emission performance, and the traditional Markov probability transfer matrix and spatial Markov probability transfer matrix are constructed to explore the spatio-temporal dynamic evolution characteristics of urban carbon emission performance in China for the first time and to predict its long-term evolution trend. The study shows that urban carbon emission performance in China presents a trend of steady increase in the fluctuation, but the overall level is still at a low level, so there is still a great improvement space in urban carbon emission performance, with huge potential for energy conservation and emission reduction. The spatial pattern of national urban carbon emission performance shows the characteristics of "high in the south and low in the north", and there is a significant difference in the level of carbon emission performance between cities. The spatial Markov probabilistic transfer matrix results show that the transfer of carbon emission performance type in Chinese cities is stable, thus it forms the "club convergence" phenomenon, and the geographical background plays an important role in the process of the transfer. From the perspective of long-term trend prediction, the future evolution of urban carbon emission performance in China is relatively optimistic. The carbon emission performance will gradually improve over time, and the distribution of carbon emission performance presents a trend of high concentration. Therefore, in the future, China should continue to strengthen research and development to improve the performance level of urban carbon emissions and achieve the national target of energy conservation and emission reduction. At the same time, neighboring cities with different geographical backgrounds should establish a sound linkage mechanism of economic cooperation to pursue coordinated development between economic growth, energy conservation and emission reduction, so as to realize low-carbon city construction and sustainable development.

在经济全球化、区域一体化的背景下，城市发展动力由内部功能集聚转向外部关系协调，城市间的关联作用愈发重要，成为“城市的第二本质”。通过文献计量分析，发现空间计量模型逐渐成为城市网络外部性定量测度的主要方法之一。从研究设计角度，空间计量模型作为城市网络外部性的定量建模工具，存在至少两方面的问题：城市网络外部性的非对称效应和城市网络的多尺度问题。本文结合城市网络外部性测度与建模，首先阐述如何规范地解读空间计量模型参数及其与网络外部性测度的对应关系；其次基于蒙特卡洛模拟实验论证非对称城市网络外部性和多尺度城市网络外部性的建模方法。研究表明：① 忽视城市网络外部性中潜在的非对称效应会显著降低模型参数估计的准确性，本文开发的非对称空间效应模型（Asymmetric Spatial Econometric Model，ASEM）可以准确识别网络外部性的非对称效应，给出更加准确的参数估计；② 忽略现实存在的多尺度网络效应，只在单一尺度对网络效应建模会造成参数估计失真，而空间多尺度统计模型（Hierarchical Spatial Autoregressive model，HSAR）为多尺度网络外部性建模提供了有效的工具，并且通过合理的模型设定，HSAR能准确区分并识别地理集聚效应和网络外部效应。

In the context of economic globalization and regional integration, urban development forces have shifted from geographical agglomeration to external network coordination. The connectivity among cities or city network is increasingly becoming “the second essence of cities”. With bibliometric analysis of urban network externality studies, we find that spatial econometric models have been increasingly employed to quantify whether, and to what extent, urban network externality matters in the developmental process of cities or regions. This study first investigated the mathematical properties of spatial econometric models and in particular, the correspondence of model parameters and various measures of urban network externality. More importantly, we highlighted two essential issues of classic spatial econometric models when being applied to model urban network externality: the asymmetric effect and scale effect of urban network externality. Then, we developed an asymmetric spatial economic model (ASEM) to capture the asymmetric effect of urban network externality and, a hierarchical spatial autoregressive model (HSAR) to deal with the scale effect of urban network externality. A series of Monte Carlo simulation experiments were conducted to assess the benefits of these two proposed methodologies. We found that: (1) Ignoring the potential asymmetric effects in the urban network will significantly reduce the accuracy of model parameter estimation. On the other hand, the proposed ASEM can accurately identify the asymmetric effects of network externalities and yield more accurate parameter estimation. (2) Ignoring multi-scale network effects in real world data and modeling the network effects at a single scale will cause serious estimation distortion. The HSAR model instead can provide a reliable quantitative method for modeling the externalities of multi-scale networks.

以往研究对于距离在网络外部性影响城市功能过程中的作用所知甚少,而且多关注城市网络外部性的正面效应,对城市间竞争以及由此所带来的网络外部性的负效应缺少分析。为了弥补已有研究的不足,本文采用空间的视角,以城市群内的城市生产性服务功能为例,建立一个核心-外围的空间结构来揭示城市生产性服务功能、网络外部性与地理距离之间的关系。研究发现：① 城市生产性服务功能强度随着远离城市群核心城市而上升,互联网渗透率和列车网络中心度会显著地强化这一效应;② 城市生产性服务功能随距离变化的机制在于竞争效应比协同效应对地理距离更加敏感,从而衰减更快,因而靠近核心城市的城市在生产性服务功能上遭受了“集聚阴影”,而远离核心城市的城市在功能上更多的受到了协同作用的支撑。本文结论为推进城市群内的分工协作与一体化发展提供了重要启示。

Producer service, as one of the important urban functions, reflects the urban ability to serve other cities in the networked urban system. Correspondingly, the urban producer service functions can be influenced by the relationships, particularly distance between these cities. Previous research paid little attention to the role which distance between cities plays in network externalities, and focused more on the positive effects of network externalities stemming from synergy, which derives from cooperation between cities, while neglecting the negative ones caused by intercity market competition. To further explore the relationship between urban functions, geographical distance and network externalities, this paper builds a theoretical city-cluster model with core-periphery spatial structure. This model hypothesizes that the impact of network externalities on the producer service functions depends on the trade-off between synergy effect and competition effect, which are closely related to the spatial relationships, or distances, between cities. Employing data of 12 city clusters in China from 2013 to 2016, and applying the employment ratio of the producer service sector to the manufacturing sector to measure the intensity of urban producer service functions, we examine the effects of geographical distance on urban producer service functions. The results reveal that: (1) the intensity of urban producer service functions increases with distance from the core city. In addition, internet penetration rate and transportation network centrality significantly reinforce this effect. (2) The mechanism is based on the difference in sensitivity to geographical distance between the competition effect and synergy effect. Seemingly, the competition effect decays more quickly with distance than the synergy effect. Thus producer service functions of the cities which are close to the core city tend to suffer the "agglomeration shadow" effect resulted from competition, while producer service functions of the cities which are further away tend to benefit from the synergy effect. The findings of this paper demonstrate that in the context of urban networks, geographical distance (urban location) still plays an essential role in the regional labor division. It also provides important insights for the promotion of the urban functional specialization and regional integration within city clusters. Cities near the core city could choose to actively undertake complementary functions of the core city; conversely, carrying out synergetic functions with the core city is a better choice for cities far away from the core city.

创新是推动黄河流域高质量发展的重要途径之一。利用2006—2018年黄河流域79个地级以上城市的面板数据，首先构建指标体系对各城市技术创新及绿色发展水平进行分析，其次通过面板计量模型深入探究技术创新对城市绿色发展的作用机理。研究表明：① 2006—2018年，黄河流域城市技术创新与绿色发展水平均得到明显提升，但空间差异显著，总体呈“下游>中游>上游”阶梯式递减特征。② 黄河流域城市技术创新对绿色发展总体上没有显著影响，但在加入技术创新的二次项后，两者之间呈现显著的“U”型非线性关系，即技术创新先抑制后促进城市绿色发展，这也验证了技术的“回弹效应”假说；③ 技术创新对黄河流域城市绿色发展的影响可以通过直接效应和间接效应共同体现，但这两种效应正好相反，即一个城市技术创新能力的提升对该城市绿色发展存在显著的“U”型（先抑制后促进）关系，但对邻近城市的作用呈现倒“U”型相反的关系。根据研究结论，从技术创新对城市绿色发展的直接效应和间接效应2个方面提出了相应的政策建议。

Innovation is one of the important ways to promote the high-quality development of the Yellow River Basin. Using the panel data of 79 cities above prefecture level in the Yellow River Basin from 2006 to 2018, this article first constructs an index system to analyze the level of technological innovation and green development of each city, and then deeply explores the mechanism of technological innovation on regional green development through panel econometric model. The results are as follows: 1) From 2006 to 2018, the level of urban technological innovation and green development in the Yellow River Basin has been greatly improved, but the spatial difference is significant, and the overall trend is “downstream > midstream > upstream”. 2) On the whole, technological innovation has no influence on urban green development in the Yellow River Basin, but after adding the quadratic term of technological innovation, there is a obvious positive “U-shaped” nonlinear relationship between them, which also shows the existence of “rebound effect”. 3) The impact of technological innovation on urban green development in the Yellow River basin can be reflected by both direct and indirect effects, but the two effects are just the opposite. That is to say, the promotion of a city’s technological innovation level has a significant “U-shaped” relationship with the urban green development, but it has an inverted “U-shaped” relationship with its neighboring cities. According to the research conclusions, this article puts forward the corresponding policy implications from the direct and indirect effects of urban technological innovation on green development. First of all, it is particularly important for the middle and upper reaches of the Yellow River basin to enhance the ability of technological innovation and strengthen the innovation-driven effect on urban green development; Then, cities in the Yellow River Basin should break the “beggar thy neighbor” phenomenon, so as to strengthen the coordinated development in the Yellow River Basin and give play to the positive spillover effect among cities.

工业生态效率是人地系统耦合状态和水平的重要表征。以黄河流域八省区为实证区域,构建工业生态效率投入产出指标体系,采用Super-SBM模型对地市尺度2006—2016年工业生态效率进行测度,分析其空间分异特征;构建计量模型,从全流域和上中下游等不同尺度,考察工业生态效率的影响因素。结果表明：① 工业生态效率整体呈提升态势,空间上呈自下游向上游递减格局,山东整体最高,河南提升较快,甘肃整体最低;下游城市群和区域中心城市的工业生态效率整体更优。② 工业生态效率具有空间自相关特征,由高-高集聚类型演化为高-高、低-低两种局域集聚类型。2006年高-高集聚类型分布在陕晋蒙交界地区和山东半岛城市群,2016年高-高集聚类型分布于山东半岛城市群、中原城市群和陕西南部,低-低集聚类型集中分布在山西、甘肃。③ 经济发展水平、工业集聚强度、科技投入、经济外向度、环境规制和经济密度对工业生态效率存在正向促进作用,但与中上游相比,下游地区工业集聚强度的影响偏弱,而环境规制的作用更强。④ 提高黄河流域工业生态效率水平,需要进一步提高经济发展水平、工业集聚强度、科技投入和经济外向度,加强环境规制。但要根据上中下游实际采取差异化措施,中上游地区因生态环境脆弱,应将清洁产业的集聚作为发展方向,提升产业集聚正外部性,支持资源型城市的经济结构转型,强化环境规制的约束。

Industrial eco-efficiency can reflect the coupling state and level of Human-Earth System. Taking the eight provinces of the Yellow River Basin as the study region, this paper constructs the input-output index system of industrial eco-efficiency, and uses Super-SBM model to measure the industrial eco-efficiency at the city scale from 2006 to 2016, and analyzes its spatial differentiation. The econometric model is constructed to examine the influencing factors of industrial eco-efficiency from different scales such as the whole basin and the upper, middle and lower reaches. The results show that: (1) The overall industrial eco-efficiency is on the rise, and it is decreasing from the downstream to the upstream. On the whole, Henan develops faster, Shandong has the highest industrial eco-efficiency, while Gansu has the lowest. The industrial eco-efficiency of urban agglomerations and regional central cities in the lower reaches is overall better (2) Industrial ecoefficiency has spatial autocorrelation characteristics. From high-high agglomeration types evolve into high-high and low-low local agglomeration types. In 2006, High-high types are mainly distributed in Shanxi-Shaanxi-Inner Mongolia border area and Shandong Peninsula urban agglomeration. In 2016, High-high types are mainly distributed in Shandong Peninsula urban agglomeration, Central Plains urban agglomeration and southern Shaanxi, and low-low types are concentrated in Shanxi and Gansu. (3) The level of economic development, industrial agglomeration intensity, scientific and technological input, economic extroversion, environmental regulation and economic density have positive effects on industrial eco-efficiency. However, compared with the middle and upper reaches, the lower reaches is weaker in the impact of industrial agglomeration intensity, while stronger in the effect of environmental regulation. (4) To improve the level of industrial eco-efficiency in the Yellow River Basin, it is necessary to enhance tthe level of economic development, the intensity of industrial agglomeration, the investment in science and technology and the economic extroversion, and strengthen environmental regulation. However, differentiated measures should be taken according to the actual situation in the upper, middle and lower reaches. As the middle and upper reaches have more fragile eco-environment, we should agglomerate clean industries so as to improve the positive externality of industrial agglomeration, support the economic structure transformation of resource-based cities, and strengthen the constraints of environmental regulations.

基于绿色发展科学内涵,综合构建了黄河流域绿色发展的评价指标体系,并采用熵值法、空间自相关分析、地理探测器模型等多种计量方法研究了2005—2017年黄河流域生态经济走廊绿色发展时空分异特征与驱动因素,结果如下：① 黄河流域绿色发展主要来源于规模化扩张与总量增长的外部驱动作用,热衷于发展速度与规模,忽视质量与效率的内涵式提升势必导致内生驱动作用不足与不可持续性;② 研究时限内黄河流域绿色发展低水平区不断减少,较高水平区稍有增加,但低水平与中低水平区占比长期稳定在65%以上,说明黄河流域绿色发展质量有待于进一步提升;③ 2005—2017年间黄河流域61地级市整体存在较为明显的空间依存关系,且绿色发展水平具有相对明显的空间俱乐部收敛特征,流域内两极分化现象较为明显;④ 经济发展水平、科学技术与政府调控始终是黄河流域绿色发展的高作用力影响因子,因子交互作用后对黄河流域绿色发展解释力远超单因子,反映出黄河流域绿色发展的驱动因素具有复杂性特征。

Based on the scientific connotation of green development, a comprehensive evaluation index system for green development in the Yellow River Basin was constructed, and various measurement methods such as entropy method, spatial autocorrelation analysis, and geographical detector model were used to study the spatio-temporal differentiation characteristics and the influencing factors of the green development in the eco-economic corridor of the Yellow River Basin. The results are obtained as follows: (1) The green development in the Yellow River Basin mainly originates from the external driving effects of large-scale expansion and the growth of total volume. Focusing only on pursuing the speed and scale of development but ignoring the connotative improvement of quality and efficiency will inevitably lead to the insufficiency of internal driving effects and unsustainability. (2) The number of areas with lower level of green development in the study area decreased continuously while that with a higher-level of green development rose slightly during the limited study period. However, the proportion of the numbers of areas with the lower level and medium-low level of green development remained above 65% for a long time, indicating that the level of green development needs further improvement. (3) From 2005 to 2017, the 61 prefecture-level cities in the Yellow River Basin generally showed relatively obvious spatial dependencies, and the green development level displayed a relatively obvious characteristic of spatial club convergence. The phenomenon of polarization in the study area was obvious. (4) The economic development level, science and technology level and government regulation are still the leading factors influencing the green development, and the explanatory power of interactions between factors for the green development far exceeds that of a single factor. This reflects the driving factors for green development in the Yellow River Basin are complex.

绿色发展战略既是实现区域经济社会与资源环境耦合协调的重要内容,也是推进区域人地协调的重要路径。研究运用投影寻踪评价模型（PPM）以及基尼系数、变异系数、空间自相关和空间计量等方法分析中国30个省市区绿色发展时空演变轨迹与影响机理,得出以下结论：① 构建涵盖“绿色增长-绿色福利-绿色财富”三个维度的绿色发展系统,三个维度的协同一致和均衡发展是绿色发展的本质特征和内在要求;② 中国绿色发展指数呈逐年上升趋势,但增长速度较低,绿色发展虽然取得了显著成效,但问题与压力依然严峻。绿色增长和绿色福利指数均呈现增长趋势,年均增长率分别为5.77%、11.74%,绿色财富指数整体相对较低且增长缓慢,一定程度上反映了绿色财富指数增长的艰巨性和长期性;③ 绿色发展及其构成指数的区域差异呈逐渐缩小趋势,但差异程度依然较大,总体呈东部地区>东北地区>西部地区>中部地区的特征,绿色财富与绿色发展及其他构成指数空间分布错位,高高、低低空间集聚特征明显;④ 城镇化水平、产业结构、人口密度、科技创新、市场化、国际贸易是影响中国绿色发展的主要因素。研究从塑造生态文化理念、发展生态高效产业、提升资源环境承载能力和优化空间治理体系等方面提出对策建议,对中国生态文明建设和绿色发展推进具有一定的借鉴参考价值。