消费升级引领战略性新兴产业全球价值链攀升——理论逻辑与中国经验

在中国经济发展模式逐步由外需转向以内需为主的背景下,本文考察需求侧本土市场消费升级对战略性新兴产业全球价值链攀升的影响,对促进实现国内国外双循环、抢占科技领域高地具有重要意义。本文综合利用2000—2016年中国各省域经济发展数据、WIOD世界投入产出表、战略性新兴产业上市公司数据、中国海关进出口数据和中国专利数据,分别从产业和企业层面系统考察了本土市场消费升级对战略性新兴产业全球价值链攀升的内在机制和作用效果。研究发现,总体上,本土市场消费升级对中国战略性新兴产业全球价值链升级具有显著的促进作用,且这一作用主要通过市场规模效应和技术创新效应实现;在考虑内生性和住房消费挤出效应等问题后,这一结论依然成立。进一步研究发现,在战略性新兴产业中,本土市场消费升级的全球价值链升级效应呈现出明显的行业、区域和所有制类型异质性;国内和国外市场消费升级均是促进战略性新兴产业全球价值链升级的重要市场基础,但国内市场消费升级已然成为培育战略性新兴产业全球价值链升级更为重要的驱动力。本文研究表明,进一步提升内需的消费质量,对于促进形成国内国际双循环新发展格局,实现战略性新兴产业全球价值链升级具有重要意义。

The Impact of Global Value Chain Embedment on Energy Conservation and Emissions Reduction:Theory and Empirical Evidence

An in-depth investigation into the effect of embedment in global value chain(GVC)on energy conservation and emissions reduction is of great significance for scientifically assessing the environmental impact of GVC participation,and promoting high-quality development in China.This paper incorporates GVC embedment,energy consumption and carbon emissions into the same analysis framework for the first time.Based on the WIOD database,this paper theoretically and empirically examines the impact and mechanism of global value chain embeddedness on carbon emission reduction from two dimensions:energy consumption intensity and energy consumption structure.The study found that GVC embedment significantly reduced the industry’s carbon emission intensity;developing economies’embedment in GVC helped reduce their carbon emission intensity,while the effect was not obvious in developed economies.GVC embedment had a significant inhibitory effect on the carbon emissions in both upstream and downstream industries,but not conducive to carbon reduction of lowtech manufacturing.The mechanism test shows that the GVC embedment not only exhibits the dual effects of energy conservation and emissions reduction,but also has a significant impact on carbon emissions by reducing the energy consumption intensity and improving the energy consumption structure.

Soil microbial communities regulate the threshold effect of salinity stress on SOM decomposition in coastal salt marshes

Salinity stress is one of the critical environmental drivers of soil organic matter(SOM)decomposition in coastal ecosystems.Although the temperature sensitivity(Q_(10))of SOM decomposition has been widely applied in Earth system models to forecast carbon processes,the impact of salinity on SOM decomposition by restructuring microbial communities remains uncovered.Here,we conducted a microcosm experiment with soils collected from the coastal salt marsh in the Yellow River Estuary,which is subjected to strong dynamics of salinity due to both tidal flooding and drainage.By setting a gradient of salt solutions,soil salinity was adjusted to simulate salinity stress and soil carbon emission(CO_(2))rate was measured over the period.Results showed that as salinity increased,the estimated decomposition constants based on first-order kinetics gradually decreased at different temperatures.Below the 20‰salinity treatments,which doubled the soil salinity,Q_(10)increased with increasing salinity;but higher salinity constrained the temperature-related response of SOM decomposition by inhibiting microbial growth and carbon metabolisms.Soil bacteria were more sensitive to salinity stress than fungi,which can be inferred from the response of microbial beta-diversity to changing salinity.Among them,the phylotypes assigned to Gammaproteobacteria and Bacilli showed higher salt tolerance,whereas taxa affiliated with Alphaproteobacteria and Bacteroidota were more easily inhibited by the salinity stress.Several fungal taxa belonging to Ascomycota had higher adaptability to the stress.As the substrate was consumed with the incubation,bacterial competition intensified,but the fungal co-occurrence pattern changed weakly during decomposition.Collectively,these findings revealed the threshold effect of salinity on SOM decomposition in coastal salt marshes and emphasized that salt stress plays a key role in carbon sequestration by regulating microbial keystone taxa,metabolisms,and interactions.

“Competition for Innovation”:Research on the Strategic Competition of Local Governments'Science and Technology Expenditure in China

By constructing a yardstick competition model of the performance equation,this paper analyzes the internal mechanism of local governments'competition of science and technology(S&T)expenditure in China.By using the Dynamic Spatial Panel Model,we analyze the competition empirically from five dimensions:geographical adjacency,geographical distance,administrative adjacency,administrative grade and economic distance.According to the results,the local governments'S&T expenditure showed a significant strategic competition phenomenon,that is,there is a“competition for innovation”,and the competition is more obvious between regions with close geographical proximity and administrative relations.“Competition for innovation”will be affected by political exogenous shocks such as those from the National People's Congress(NPC)of China;There is a“father-son competition”relationship between the superior and inferior governments.At last,the competition can promote the regional innovation significantly,which shows that“competition for innovation”is a kind of top-by-top competition.The conclusions may provide some useful suggestions for optimizing the relationship between local governments and promoting the construction of an innovative country.

区域市场整合、贸易开放与资源错配

基于中国2003-2016年的省际面板数据,构建综合考虑商品、资本和劳动力市场整合情况的区域市场整合指数,并对各地区的资本错配和劳动力错配情况进行测度。在此基础上,采用两阶段最小二乘法2SLS对区域市场整合、贸易开放与资源错配的关系进行深入检验。主要的研究发现有:样本期内国内市场整合情况可以分为两个阶段:2003-2008年,国内市场整合程度呈缓慢下降态势;2009-2016年,国内市场整合情况在波动中趋于上升,且2013年之后上升速度加快。区域市场整合显著促进了资源错配的改善,而当前的贸易开放却加剧了资源错配。这对经济新常态下中国统筹协调国内外市场发展,优化资源配置,以培育经济增长新动力具有一定的启发意义。

Changes of wetland landscape patterns in Dadu River catchment from 1985 to 2000, China

Based on the interpretation and vector processing of remote sensing images in 1985 and 2000, the spatial changes of wetland landscape patterns in Dadu River catchment in the last two decades were studied using spatial analysis method. Supported by Apack soft-ware, the indices of wetland landscape pattern were calculated, and the information entropy （IE） was also introduced to show the changes of wetland landscape information. Results showed that wetland landscape in this region was characteristic of patch-corridor-matrix configuration and dominantly consisted of natural wetlands. Landscape patterns changed a little with low fragment and showed concentrated distribution with partial scattered distribution during the period from 1985 to 2000. The values of patch density and convergence index kept stable, and the values of diversity, evenness indices decrease, while dominance and and IE showed a slight fractal dimension indices were increased. All types of wetland landscapes had higher adjacency probabilities with grassland landscape in 1985 and 2000, and there was extremely weak hydrological link and large spatial gap among river, glacier, reservoir and pond wetlands due to low adjacency matrix values. Since their cumulative contribution exceeded 81% through the PCA analysis, the agriculture activities would be the main driving force to the landscape changes during the past 15 years.

城市规模、发展模式与企业加成率

本文基于集聚经济外部性视角,匹配中国工业企业数据和地级及以上城市数据,对城市规模、发展模式与企业加成率的关系进行了探讨。研究发现:城市规模与发展模式密切相关。随着规模扩大,城市倾向于由专业化发展转向多元化发展,但二者并非相互排斥,多元化指数较高的城市完全有可能在某些产业上实现专业化发展。中国城市规模进一步扩大将有利于提高企业加成率。同时,城市专业化发展与企业加成率之间呈现出在低水平时促进、在高水平时抑制的倒U型关系,但总体上并未超过阈值拐点,说明城市继续沿着专业化方向发展将促进企业加成率的提升。然而,由于中国城市的多元化发展模式并不突出,导致多元化指数与企业加成率之间的倒U型关系并不稳健;分层样本的异质性检验发现,与当前中国城市的发展现状相吻合,大型城市的专业化发展更加易于饱和,而中小型城市对于专业化发展的包容性更强,且在多数产业部门中城市多元化发展对企业加成率的影响并不显著。因此,大型城市可以兼顾专业化发展和多元化发展,而中小型城市应当选择专业化的发展模式,着力引导相似产业部门的企业集聚。本文的研究对于理解城市与企业的关系,进而推动产城融合发展具有重要的理论与现实意义。

财政压力对地方政府科技投入的影响研究——来自281个地级市的经验证据

实施创新驱动发展战略离不开政府对科技活动的支持与导向,加大地方政府对科技活动的财政激励对于提升国家科技实力,进而推动建设创新型国家具有重要意义。本文以分税制改革以来地方政府形成一定财政压力和2012年起逐步开展的"营改增"为现实背景,旨在考察财政压力对地方政府科技投入的影响效果,在理论分析其作用机制并提出假设的基础上,采用2008—2015年281个地级市面板数据进行了实证研究。研究发现:财政压力对地方政府科技投入具有显著的负向影响;"营改增"与财政压力存在交互效应,"营改增"本身会促进地方政府科技投入,但在财政压力条件下,"营改增"对地方政府科技投入亦具有显著的负向影响;官员任期和城市异质性是影响财政压力与地方政府科技投入之间关系的重要因素。在使用工具变量法和双重差分法处理内生性问题,进行官员任期分组检验和城市异质性分析,以及考虑科技投入的空间和动态效应后,本文结论依然稳健。本文结论为进一步深化财税体制改革,推动地区创新发展提供了政策启示。

政府科技资助对企业技术进步的影响——基于“门槛回归”的实证研究

在采用索洛余值法和Malmquist指数法测算我国大中型工业企业分行业技术进步指数的基础上,利用＂门槛模型＂考察政府科技资助对企业技术进步的影响效果。实证研究发现,政府科技资助对企业技术进步的影响存在显著的门槛效应。这在一定程度上表明政府科技资助对企业技术进步的影响存在一个最优的资助水平区间,位于这一区间内的政府科技资助对企业技术进步具有显著的促进作用。研究结论为政府科技资助政策的科学制定,进而提升资助效果提供政策启示。