In the era of digital economy, digital technology has brought profound changes to the production system of creative industries. The influence of virtual space built on Internet platforms on physical geographical space is increasing, which destroys the old spatiotemporal relationship, new socioeconomic organization geospatial pattern is created, and the changing importance of geographical proximity and its role in the decentralization of cultural production remain to be explored. In order to examine the impacts of new digital technologies on the geographies of cultural production and to provide a reference for exploring the high-quality development model of cultural industry in the new era, this study applied social network analysis and negative binomial gravity model to examine the urban cooperative network structure and multi-dimensional proximity mechanism of the online game industry, based on the data of Chinese online game projects from 2016 to 2020. The conclusions are as follows: First, the new digital technology has strengthened the decentralization and agglomeration trend of the online game industry. The findings demonstrate the dominant role that external networks play in the operation of online game projects. Small and medium-sized cities rely more on cross-regional cooperation networks in particular, because they lack strong and influential local companies. Second, the connections between cities based on the division of value chain of the online game industry are relatively sparse, the cooperative network presents an uneven diamond-shaped connection pattern, the spatial pattern of the network is highly imbalanced, and the industry is mainly concentrated in the economically developed eastern coastal region. There is a mismatch between the influence of cities in the network and the scale of local clusters. The network hierarchy basically follows that of China's existing urban system, and the core nodes are highly concentrated in Beijing, Shanghai, Shenzhen, and Guangzhou. Local administrative centers also play an important role in the cooperation network. Social proximity, cognitive proximity, urban industrial scale, external connectivity, and human capital have positive effects on the establishment of cooperative network in the online game industry, while the wide application of digital technology makes the effects of geographical proximity and institutional proximity insignificant. At present, the main channel for enterprises in remote areas to obtain resources is still the dominant cultural production centers, which is related to the complex and diverse urban structure system in China.
The existing research lacks attention to the borrowed size of cities in urban agglomerations. To fill this research gap, this study examined the existence, spatial conditions, and formation mechanism of borrowed size in 14 urban agglomerations of China from the dimensions of function and performance based on the data of cities above prefecture level in 2008-2019. The results show that: 1) Cities in seven urban agglomerations, namely, Chang-Zhu-Tan, Pearl River Delta, Wuhan, Central and Southern Liaoning, Harbin and Changchun, Beibu Gulf, and Beijing-Tianjin-Hebei regions, have borrowed size. Large cities are more likely to borrow function and borrow performance, that is, there is borrowed size, while small and medium cities are more likely to borrow function. Five urban agglomerations, namely, Chengdu-Chongqing, Central Plains, Shandong Peninsula, Guangdong-Fujian-Zhejiang Coast, and Yangtze River Delta regions, have agglomeration shadow. 2) Borrowed size occurs more frequently in urban agglomerations with polycentric structure. Large, medium, and small cities can borrow function by being embedded into urban agglomerations of polycentric structure, but only medium and large cities can borrow performance in urban agglomerations of polycentric structure. Polycentric structure has the most obvious impact on the borrowed function and borrowed performance of medium cities. 3) Enhancing the geographical proximity of cities will reduce the borrowed function, but can improve the borrowed performance. Enhancing the network relevance of cities can improve the borrowed function and borrowed performance. For borrowed function, there is a substitution effect between network relevance and geographical proximity, and for borrowed performance, there is a complementary effect between network relevance and geographical proximity. The stimulation of network relevance on borrowed function and borrowed performance can only be seen in large cities.
The relationship between regional centers and hinterland has always been a classic content in the research of regional and urban development. The process of globalization and informatization yielded "space of flows" and "central flow theory", and provided theoretical supports for the research on urban relationships. Inter-city relationships reflected by enterprise linkage flows have been widely explored by scholars, but most studies focused on urban networks of the "whole space". They rarely focused on specific issues and placed the central city in a larger regional scope. Based on firm data at the county level from 1990 to 2018, this study examined the spatial-temporal evolution and influencing factors of local and nonlocal enterprise linkages of Beijing with the hinterland and external regions to provide an explanation for the economic gap between Beijing and its hinterland—Hebei Province—from the perspective of enterprise linkages. The main conclusions are as follows: 1) From 1990 to 2018, local enterprise linkages of Beijing were weak. Counties with strong enterprise linkages were mainly concentrated in nonlocal areas such as the Yangtze River Delta. Nonlocal was the main form of enterprise connections of Beijing. In terms of investment, Beijing had the strongest local connections in manufacturing industry, and the strongest nonlocal connections (mainly with the Yangtze River Delta) in leasing and business services industry. In terms of branches, Beijing had both the strongest local and nonlocal connections in financial industry. 2) Beijing's local enterprise linkages were affected by local financial environment, government intervention, geographical proximity, and policy environment, while its nonlocal linkages were affected by political resources, technology input, economic openness, and consumption level. Among these factors, consumption level and market development had a negative impact on the connections of nonlocal enterprises, while the rest had a positive impact. There was some resistance for Beijing’s firms to establish local ties, which made them more inclined to establish nonlocal connections with regions with superior market potential and business environment.
Under the background of Shanghai's strategy to step up efforts to develop the five new urban centers in the Yangtze River Delta urban agglomeration, the construction of new urban centers has entered the stage of building comprehensive node cites (CNCs). Nevertheless, it is not clear whether the five new urban centers are suburban satellite cities or CNCs. Based on the headquarter-branch linkages of whole industrial enterprises in 2001, 2010 and 2018, this study built a directed-weighted urban network at the county scale to depict the change of spatial structure of the urban network in the Shanghai Metropolitan Area (SMA). Then, this study examined the network position of the five new urban centers in SMA by using social network analysis. Furthermore, this study introduced spatial econometric models to uncover the relevant influencing factors. The research findings reveal that: First, the original core-periphery structure, with the Shanghai central city (SCC) as the core, gradually evolved into a flat structure, in which administrative constraint is evident. Second, the five new urban centers have not shown centrality characteristics of node cities but exhibit a certain degree of independence, and there is still a great gap from becoming CNC. Third, the impact of innovation capacity, environmental quality, and transportation infrastructure on the centrality of new urban centers is significantly enhanced. Urban population, policy preference, and public services have a sustained positive impact on the centrality of new urban centers. From the perspective of corporate networks, this study provides policy recommendations for the development of five new urban centers as CNCs in SMA.
How cities introduce new industrial development paths is the key to industrial upgrading and leapfrogging, but it is unclear what types of firms are better positioned to lead this transformative process. Using Chinese customs trade data and the dynamic evolution of firm export products as an entry point, this study dismantled the local embeddedness of firms in terms of their local market position, local survival years, and political embeddedness to examine what types of firms are more likely to introduce new products to cities, and to explore the spatial and temporal differences. The study found that: 1) In general, firms with higher local market position and shorter duration of existence are more likely to introduce new products to cities. 2) Private firms introduce the largest number of new products to cities, but their role is insignificant in the central, western, and northeastern regions. 3) The average number of new products introduced by state-owned enterprises is twice that of other types of enterprises. The empirical results show that the role of state-owned enterprises is most stable, with a significant positive effect in all regions and time periods. 4) For cities in eastern China, firms with higher local market position and shorter duration, as well as state-owned enterprises and private firms, are more likely to introduce new products to these cities. 5) For cities in central, western, and northeastern China, firms with lower local market position and shorter duration, as well as state-owned enterprises, are more likely to introduce new products to these cities.
Urban-rural integration has great significance for the effective implementation of rural revitalization and urban sustainable development in China, but shrinking cities have emerged in the process of rapid urbanization. Characteristics of urban-rural integration development of shrinking cities and the impact of urban shrinkage on urban-rural integration have become one of the core scientific issues to be addressed in the current research on promoting the goal of common prosperity in China. This study constructed an evaluation indicator system based on the definition of urban-rural integration, with the driving force-pathway-goal of "urban development driven-coordination of urban and rural investment-promoting the balance of basic public services and narrowing urban-rural income gaps". It took the three northeastern provinces as examples and conducted an empirical analysis of urban-rural relationship in 2010-2019 from the perspective of shrinking cities and non-shrinking cities, different development stages, and different development types of shrinking cities. The results show that: 1) The overall development of urban-rural integration in the three northeastern provinces showed an upward trend, but the development level is still low and the internal spatial differentiation is obvious. 2) Urban shrinkage has an obvious impact on urban-rural integration, and the overall level of urban-rural integration in shrinking cities is lower than that of non-shrinking cities. Urban and rural dual structure is more obvious in shrinking cities. 3) Urban-rural integration development level shows differences in cities of different shrinkage types and shrinkage development stages. The level of urban-rural integration decreased gradually from pre-shrinkage stage to post-shrinkage stage, and resource-dependent shrinking cities < comprehensive shrinking cities < "siphon" shrinking cities < location-constrained shrinking cities. Therefore, this study concluded that shrinking cities are affected by the "spatial deprivation" of development factors on urban-rural integration development. The emergence of shrinking cities is not conducive to regional coordination and the integration of urban and rural development, and the sustainable development of shrinking cities should be fully considered in the revitalization of Northeast China.
As the hydrological cycle changes intensify with climate warming, the relationship between runoff and climate change has become a hot topic of research. This study simulated runoff changes between the three distinct climate stages during the last millennium—that is, Medieval Climate Anomaly (MCA), Little Ice Age (LIA), and Modern Warm Period (MWP)—in the upper and middle reaches of the Yellow River using the BCC-CSM1-1 simulation dataset and carried out an attribution analysis with the Budyko Hypothesis and Fu's Formula. The results showed that: 1) At the upper reaches of the Yellow River, there was higher runoff in the MWP and lower runoff in the LIA, and the phase of runoff change was the same as temperature anomaly. However, at the middle reaches of the Yellow River, there was higher runoff in the LIA when it was the coldest while lower runoff in the MCA and MWP when it was warmer. 2) The sensitivity of runoff to various factors showed a geographical difference and was affected by the shift of warm-cold conditions between different climate stages. The elasticity coefficients (absolute value) of runoff to precipitation and potential evaporation in the middle reaches were greater than in the upper reaches, and they were slightly larger during the cold to warm transitional period than in the warm to cold transitional period. Meanwhile, the elasticity coefficient (absolute value) of runoff to land surface changes in the upper and middle reaches during the continuous warming period was significantly greater than in the warm-to-cold and cold-to-warm transitional periods. 3) The runoff discrepancy during the three distinct climate stages was mainly dominated by precipitation, with little influence from land surface change. But there were regional differences in the role of potential evaporation. The effect of potential evaporation in the upper reaches partially offsets the contribution of precipitation to the runoff changes while the potential evaporation in the middle reaches strengthens the runoff changes caused by precipitation.
The characteristic indicators of flood process include not only flood magnitude, but also flood duration, dynamics, and so on. The existing models and methods focus on the simulation of flood magnitude indicators, but the simulation of other indicators remains insufficient. In this study, four machine learning models — multiple linear regression, multi-layer perceptron, random forest, and support vector machine — were used to simulate seven characteristic indicators — total flood volume, peak flow, flood duration, time deviation of flood peak, proportion of high flow duration, flood rise and fall rates — of 59 rainfall-flood events in the Changtaiguan Basin in the upper reaches of the Huaihe River. The simulation performance of the models for different flood types and characteristic indicators were evaluated. The results show that: 1) The flood process in the Changtaiguan Basin can be divided into three categories. The first category is characterized by moderate flood volume, long duration, and earlier peak time (16 fields); the second type has low flood volume, short and fat shape, and the flood peak appears later (34 fields); the third type has large flood volume, sharp and thin shape, and flood rises and falls rapidly (9 fields). 2) Time indicator simulation performed the best and dynamic indicator simulation performed the worst; the performance of multiple linear regression and random forest simulation increased with the increase of all characteristic indicator values. The simulation performance of support vector machine decreased with the increase of flood duration, and increased with the increase of value of the remaining characteristic indicators. The simulation performance of multi-layer perceptron increased with the increase of value of four indicators, namely, total flood volume, peak flow, proportion of high flow duration, and flood rise rate. 3) With regard to the simulation accuracy of characteristic indicators of various types of floods, the four models performed the best for the simulation of the third type of floods, but the worst for the second type; random forest showed the best simulation performance for the first and third types of floods, and support vector machine showed better simulation performance for the second type of floods. 4) According to the comprehensive simulation accuracy, the support vector machine model performed the best, followed by random forest, multi-layer perceptron, and multiple linear regression. Relative errors for the calibration and validation periods were 23% and 98%, 21% and 109%, 37% and 75%, and 41% and 102%, respectively. The study results may provide some references for flood type simulation and countermeasures in the Huaihe River Basin.
Nighttime lights are one of the direct representations of urban social and economic activities, which usually decrease with the distance from urban centers. However, quantifying and modeling the process of distance decay can be challenging, and the potential applications of nighttime light data are not specified. In this study, the annual composites of NPP-VIIRS nighttime lights for 32 major cities in China in 2012 and 2020 were obtained and used to calculate the nighttime light intensity within concentric circle layers by taking the city center as the center of the circle. Inspired by the spatial attenuation function of urban land density, this study used the inversed-S function to fit the distance decay characteristics of urban nighttime light intensity. The results show that the inversed-S function model fits the distance decay characteristics well, and the parameters D and α of the model reflect the process of urban expansion and urban form changes, respectively. From 2012 to 2020, the radius of the cities (parameter D) increased by 1.1-3.6 times. Among the sample cities, smaller cities—Changchun, Yinchuan, and Xining—experienced the greatest expansion of nighttime lights, while eastern coastal cities experienced the least expansion. The change of parameter α indicates that the expansion pattern of nighttime lights in China's major cities tends to be compact. The inversed-S function provides a new tool for describing the spatial pattern of nighttime light intensity and a new indicator for measuring urban expansion and urban form change.
Agglomeration characteristics of tourist sources are an important content of the research on the spatial structure of tourist source market, but the existing customer source concentration indices cannot be compared horizontally and it is difficult to explain the driving factors. In this study, we proposed a calculation method of tourist source concentration index tourCI that supports the introduction of different influencing factors, established a conceptual framework of tourist source spatial structure interpretation based on the tourCI index, and provided the multi-dimensional description and meaning analysis of tourCI to calculate the distribution and agglomeration characteristics of tourist source areas under the influence of different factors. Taking Dali ancient town as an example, we used the Sina Weibo data to calculate tourCI based on administrative regions, which shows that local tourists in Yunnan Province have an important impact on the tourist source distribution characteristics of Dali ancient town, and the distribution of tourists outside Yunnan Province is relatively balanced. tourCI based on distance describes the variation of the distribution characteristics of tourist sources in Dali ancient town with the change of distance to the destination. From near to far the index of each distance segment shows a weak-strong-weak-equilibrium change pattern. The results of economic dimension show that tourists from the first tier cities are highly concentrated in areas with high economic development levels, and tourists from the new first tier cities are not significantly affected by economic factors and are evenly distributed. The distribution of tourist sources from second and third tier cities is greatly affected by economic factors. Theoretical and empirical analyses show that tourCI index has a good analytical capability for the agglomeration characteristics and driving factors of the spatial structure of tourist sources, which helps enrich the methods of tourism geography research.
In order to reveal the Holocene environmental change and its impact on human activities in Xi'an, the environmental conditions of Holocene soil layer formation in Bailuyuan were examined by using the indicators of soil element content, CaCO3 content, and magnetic susceptibility. The results show that the middle Holocene paleosol in this area has been subjected to moderate chemical weathering and has not yet reached the potassium removal stage. The soil type is subtropical yellow brown soil. The average annual temperature during the development of this layer of paleosol was about 16 ℃ and the average annual precipitation was about 920 mm. The middle Holocene summer monsoon was dominant, and the precipitation brought by the summer monsoon was about 570 mm. The late Holocene loess was chemically weathered to a low degree and was characterized by alkaline brown soil. The average annual temperature during its development was 11-13 ℃ and the average annual precipitation was 600-700 mm. The activity of the late Holocene summer monsoon was similar to that of the winter monsoon, and the precipitation brought by the summer monsoon was about 350 mm. During 6000-5000 a BP in the late middle Holocene, the climate became cold and dry. During the cold and dry period, soil erosion was strong. The accumulated loess was eroded and disappeared in a large area and remained only in a few sections. The accumulation rate of sandstorm deposits in the late Holocene loess was at least 2.3 times that in the middle Holocene paleosol. The warm and humid climate in the middle Holocene led to strong soil viscosity, good water holding capacity, and sufficient soil water content, which was very conducive to the development of temperate crops and some subtropical crops and agricultural production at that time, and was the main reason for strong human activities and wide distribution of human settlements at that time. The late Holocene loess also has excellent soil property. During its formation, the precipitation and soil water content can basically meet the needs of agricultural production in temperate drylands, which is one of the important reasons for the gradual enhancement of human activities on the Guanzhong Plain in the late Holocene.
Cultivated land use system has a great impact on global change and human well-being. This study used the theories and methods of system science to explore the concept, composition, operation, functions, and characteristics of cultivated land use system and constructed the research framework of cultivated land use system, in order to promote the deepening of land system research and solve various problems. The main conclusions are as follows: 1) Cultivated land use system is a compound natural-human system in which agricultural producers and operators invest an appropriate amount of production factors in a certain amount and quality of cultivated land to plant crops, and obtain agricultural products and corresponding benefits. Cultivated land use system consists of cultivated land subsystem, economic subsystem, and social subsystem. It has explicit and implicit structures. 2) The operation and evolution of cultivated land use system is the result of natural ecological processes, economic development processes, and social evolution processes. It also has compound, open, resilient, and multi-level characteristics. 3) The study of cultivated land use system should follow the theoretical framework of element-structure-function-mechanism-regulation. This study revealed the action mechanism of different elements from the composition and influence relationship of various elements; analyzed the structure and transformation of cultivated land use from two aspects of explicit and implicit structure; revealed the impact of functions on structure from three aspects of economic, social, and ecological functions; analyzed the operation mechanism of cultivated land use system from the adaptation and adjustment mechanism of the system to the changes of external environment, the interaction and competition substitution mechanism of system elements, the information transmission mechanism of system operation, the coordination and organization operation mechanism of cultivated land use subjects at different levels, and the emergence mechanism of cultivated land use functions; and used scenario simulation method, multi-objective optimization method, and comprehensive regulation balance method to explore regulation strategies of cultivated land use.
As the use of digital technology gradually pervades all aspects of rural production and life, the countryside is no longer a traditional, stable, and endogenous representation. In parallel, the interaction between digital technology and rural subjects has made the rural economy, society, and culture increasingly complex, and the interaction of the two dynamically reconstructs rural areas. Digital technology has gradually infiltrated from the external system of the countryside to its internal system, changing the internal operation and self-organization mechanism of the countryside. In addition, the transformation of rural space under the impact of informatization is not only embodied in the material aspect, but also in the reconstruction of the social and cultural spatial significance as well as the reconstruction of the territorial system of human-environment relationship, which reshapes rural discourse-power system and the subject identity in endogenous logic. From the perspective of humanism, it is of great significance to think deeply about the interaction between digital technology and people in the information age, such as the subject-object relationship between people and technology on the countryside, the change of discourse-power of rural society, and the change of people's family roles. However, these issues have not been discussed in depth at present. Accordingly, by discussing the multi-dimensional relationship between digital technology and rural development and its multiple effects on the rural space, and paying attention to the alienation and freedom brought by digital technology, the change of discourse and power caused by digital economy, and the reconstruction of the status and identity of women in rural areas, this article explains how digital technology as a non-human actor constructs the rural daily economic life and social relations. This article also provides theoretical analysis for explaining the subjectivity of digital technology as a non-human actor and studying hybrid rurality. It contributes a useful supplement for the analytical framework of rurality and provides a new perspective for digital rural construction and rural revitalization.
Territorial space function is an important theoretical foundation for revealing the coupling relationship between human and the environment and for informing the practical framework of spatial planning. However, trapped in the parallel thinking of land use planning and urban planning for a long time, and the territorial space planning is still in the exploratory stage, the concept of territorial space function was rarely touched upon, let alone a systematic reporting of relevant studies. Based on a review of the literature, this research found that international studies on territorial space function tended to explain complex social problems by constructing theoretical models, while studies in China focused on innovating the existing knowledge framework to guide the phased planning practice. Moreover, a systematic review was conducted on the studies of territorial space function from the aspects of classification and evaluation, spatial-temporal evolution, dynamic trade-offs, and simulation optimization, and the results indicate that although attention has been paid to the topic, there is a general lack of exploration of localization under the current circumstances. It is urgent to carry out research on the theoretical breakthroughs and practical needs of optimizing territorial space development pattern and promoting the construction of ecological civilization. By summarizing the research results in China and abroad, we put forward the future direction of territorial space function research: 1) Theoretical research of territorial space function in the era of comprehensively advancing ecological civilization. 2) Trade-off mechanism of territorial space function research in the process of governance modernization. 3) Content expansion of territorial space function study under the new-type globalization perspective. 4) Technical revolution of territorial space function study supported by advanced artificial intelligence. 5) Transformation of thinking of territorial space function study under the orientation of humanization.
Agglomeration economy theory has been intrinsically linked to urban economic growth since its inception. This article systematically reviewed the origin and development of agglomeration economy theory, summarized the core ideas of agglomeration economy in explaining the formation and development of urban space, and suggested that agglomeration economy and urban economic growth are intrinsically related. In addition, this article reviewed the impact of agglomeration economy on urban economic growth, and found that the agglomeration economy represented by increasing population density can significantly promote urban economic growth, and the explanatory mechanism of urban agglomeration economy effect can be explored from two perspectives: macro-processes and micro-processes. This article is not only a review of the literature on agglomeration economy theory and urban economic growth, but also a reference for empirical analysis of the impact of agglomeration economy on urban economic growth in China.
Hydrological models are an important scientific tool for understanding the basic theory of hydrology disciplines, analyzing hydrological processes, and studying hydrological cycle mechanisms. The uncertainty analysis of simulation results is a prerequisite for improving the reliability of a model and for conducting an effective hydrological regime forecast. Parameter uncertainty is one of the important factors that affect the uncertainty of simulation results from hydrological models, and the analysis of model parameter uncertainty and its impact factors has important practical significance for hydrological forecasting. The current parameter uncertainty analysis methods can be roughly divided into three categories: parameter sensitivity analysis, parameter optimization, and parameter regionalization method that consider the parameter estimation in ungauged catchments. This?article reviewed the current development of technique and operation status of parameter sensitivity analysis for hydrological models, as well as the advantages and disadvantages of different analysis methods. We also identified the potential development direction of future research on the method of uncertainty analysis of hydrological models, that is, to strengthen the study of the systematic method of uncertainty analysis for hydrological models with the help of multidisciplinary theories and technical methods.
