China is currently undergoing a pivotal transition towards an innovation-driven economy, and there is an urgent need for universities to play a more significant role in regional innovation. A systematic review of the relevant theoretical and empirical studies in Western economic geography can provide a scientific basis for China to further clarify the functions of universities in the innovation system and to formulate regional innovation strategies. In this study, the role of universities in regional innovation was first conceptualized from six dimensions: human capital, knowledge transfer, knowledge brokers, entrepreneurial activities, engagement patterns, and innovation effects. These dimensions stem from the three missions of universities, namely teaching, research, and regional development. Second, we analyzed the dominant channels, spatial scales, influencing factors, and corresponding policy implications of universities' engagement in regional innovation by reviewing six theoretical frameworks—the linear innovation model and university knowledge spillover, the nonlinear interactive innovation model and relational university, the regional innovation system and regional innovation system university, the triple helix and entrepreneurial university, the adaptive response and engaged university, and the innovation network and broker university. The contributions of these theoretical frameworks to the study of the six dimensions were then compared. Third, the applicability of three empirical methods—case studies, econometric modeling, and social network analysis—was evaluated in terms of their suitability for conducting research on the six dimensions. Fourth, research frontiers were outlined in terms of the channel complexity and regional heterogeneity of universities' external impacts, and the optimization of theories and methodologies for assessing the role of universities. The extant literature on the theoretical frameworks that inform our understanding of the role of universities in regional innovation presents three major trends: 1) Intellectual property activities in universities have been progressively emphasized, with the objective of emulating the successful practices of a few exemplary universities. 2) The third mission of universities is being expanded by key theoretical frameworks dedicated to meeting the development needs of the host region. 3) Functional distances of universities that influence external regions are gradually being superseded by a regional scale, with the aim of enabling universities to serve local development. Theoretical frameworks on this topic are closely related to development strategies and innovation policy adjustments across countries. Additionally, our findings indicate that the three empirical methods have been extensively employed to investigate the role of universities in regional innovation. However, it is evident that none of these methods can fully address the six dimensions of research simultaneously. Case studies are frequently used to examine engagement patterns, while econometric models offer distinct advantages in the analysis of knowledge transfer and innovation effects. Social network analysis is also gaining prominence in the examination of knowledge transfer and knowledge brokers. As in Western universities and regions, intellectual property activities have become the primary means of knowledge and technology transfer in universities in China. However, the contribution of Chinese universities to regional innovation remains limited. In light of these findings, future research should focus on the Chinese context and regional differences, employing a combination of empirical methods to examine the role of universities in regional innovation.

As an extension of human society's real space, cyberspace carries a variety of social practice activities. This new mode of implementation of practical activity has triggered a paradigm shift in society, making cyberspace a new strategic space for nations. Based on theories of spatial production and relational geography, this article holds that space is a product of relations and employs an actor-network-space model to analyze the mechanisms of cyberspace production. It categorizes actors in cyberspace into individual users, network enterprises, and governments. The social, production, and power relations among these actors constitute community network spaces, platform network spaces, and national network spaces. In community network spaces, individual users engage in practical activities based on their own needs. In platform network spaces, network enterprises attract more users by analyzing data generated from user practices, forming a positive cycle that promotes the production of cyberspace. In national network spaces, governments govern cyberspace based on the power they possess in the real world, maintaining national cybersecurity. The characteristics of relational centrality determine that there will inevitably be actors in a dominant position in relations. There is competition for dominance in cyberspace relations in the global network space. Network infrastructure resources are the foundation of global cyberspace competition and determine the upper limit of each country's development in cyberspace. Diverse practical activities are key to obtaining a dominant position in cyberspace, and high-vitality spaces are more attractive to users. Technological innovation is a safeguard for consolidating a position in cyberspace, as new modes of practical activity can create more network relations. China should explore cutting-edge technologies, innovate spatial production methods, actively participate in the formulation of global cyberspace-related technical standards, deepen exchanges with other countries' cyberspaces, and transform China's advantage in network practice volume into a competitive advantage in cyberspace. The foundation of the prosperity and development of cyberspace lies in the relations formed by interactions among actors. Actors in cyberspace should follow the principle of a "community with a shared future for mankind", coexist harmoniously in the global cyberspace, enrich cyberspace relations together, and promote the prosperity of the global cyberspace.

Cooperative innovation in the photovoltaic industry among global cities is a crucial cornerstone for sustainable development worldwide. Examining the evolution of innovation cooperation networks among global cities and the changing status of Chinese cities holds significant strategic importance for the development of strategic emerging industries and the enhancement of cities' status. Based on the patent cooperation data from 2000 to 2022, this study constructed innovation cooperation networks among 1382 global cities. Considering the life cycle of photovoltaic products, and using complex network analysis methods, this study elucidated the topological structure and spatial change of the global intercity photovoltaic industry innovation cooperation networks. Then, the changing status of Chinese cities was revealed. The results show that: 1) With the technology of the photovoltaic industry evolving from nascent stage to rapid growth and then to maturity and stability, the intensity of global photovoltaic industry innovation cooperation first grew and then became stable. 2) The global photovoltaic innovation cooperation network exhibited a pronounced spatial clustering, primarily concentrated in the eastern United States, Western Europe, and East Asia. The innovation network has transitioned from a "few-core dominance" centered on cities in the United States and Japan to a "multi-core interconnected" structure, gradually evolving into innovation clusters dominated by cities in China, India, Europe, and the United States. 3) City scale and innovation level had a significant positive impact on the intensity of photovoltaic industry innovation cooperation of cities. The carbon reduction policy had a strong driving effect on photovoltaic industry innovation in the early stage, but later showed a diminishing marginal effect. 4) Cities in China, represented by Beijing, Shanghai, Suzhou, and Shenzhen, have shown a continuous upward trend in their betweenness centrality and weighted centrality within networks. They have gradually transitioned from primarily importing technology to establishing mutually beneficial relationships in technology with domestic and international partners, ultimately evolving into technology exporters. Understanding the spatiotemporal change of the global photovoltaic industry innovation cooperation networks and the changing status of Chinese cities within it holds significant promise. It is expected to promote the restructuring of the photovoltaic industrial chain and the reconfiguration of the value chain. This, in turn, can reshape the spatial pattern of strategic emerging industries and regional innovation activities.

Photovoltaic (PV) power is one of the fastest-growing renewable energy sources globally, playing a pivotal role in driving the transformation of energy systems and reducing carbon emissions. To promote the expansion and rational layout of the domestic PV industry, the Chinese government has implemented a gradually declining national feed-in tariff policy for PV power generation setting by region and by category during 2012-2020. Quantitatively assessing the effectiveness of this policy is of great significance. This study aimed to provide a deep understanding of the mechanisms and effectiveness of the national PV feed-in tariff policies during its full evolution period (2012-2020). It explored the spatiotemporal patterns of centralized and distributed PV installations in China, their responses to the change of feed-in tariff policies, and the interactions between these policies and other influencing factors. Specifically, the study selected factors influencing PV power generation from four aspects: resource endowment, absorption capacity, construction capability, and policy factors. It identified five characteristic time points in the evolution of the policies—2012, 2014, 2016, 2018, and 2020—and conducted analysis at the provincial level. The geographical detector model (Geo-detector) was employed, which does not assume linearity. The findings indicate that: 1) There was a synergistic trend between the scale of China's categorized PV installations and the feed-in tariff policy, and the gradually declining subsidy has an inverted "U-shaped" influence on the scale of China's PV power industry, transitioning from strong stimulation to timely moderation. This aligned with the industry's periodic characteristics and phased developmental demands. 2) The regional and categorized feed-in tariff policies have spurred rapid expansion in the scale of distributed PV installations. This growth has complemented the increase in centralized installations spatially, contributing to an overall eastward shift and a more balanced development in China's PV power spatial pattern. 3) The synergistic effect of feed-in tariff policies with other factors has been enhanced overall, particularly by significantly enhancing the role of absorption capacity factors while relatively suppressing the role of resource endowment factors. This dual effect has promoted a shift in China's PV power from a supply-oriented growth model to one that is demand-driven and supply-demand balanced. Furthermore, it has optimized the spatial allocation of PV power resources. Overall, the PV feed-in tariff policies and their change have optimized the regulation of the spatiotemporal pattern of China's PV power, both through their direct impact and through synergies with other factors.

Changes in the spatial organization of regional (city) production trigger the restructure of manufacturing supply chain networks, providing a new perspective for urban network research. Using the transaction data of the top five customers and suppliers of listed manufacturing companies in the Yangtze River Delta from 2001 to 2020, this study mapped intercity manufacturing supply chain networks, with cities as the unit of analysis. It employed the social network analysis method to study the process of change of these networks and used TERGM to investigate their influencing factors. The research found that: 1) There was significant spatial heterogeneity in manufacturing supply chain linkages, with the process of change exhibiting notable spatial and path dependencies. Connections with the eastern region were consistently the strongest, while those with the northeastern region were the weakest, and connections with the central region were consistently stronger than those with the western region. 2) The network demonstrated clear hierarchical and disassortative characteristics. Intercity connections have become increasingly tight, although competition among core nodes was intense, and the network scale first increased and then decreased. 3) In terms of internal network relationships, mutuality, transitivity, and three-party groups had a significant promoting effect on the development of the network. Regarding external network relationships, factors such as labor resources, technological levels, geographical distance, and economic proximity also played a significant role in network change. This study helps to gain some insights into the dynamic characteristics of the supply chain in the manufacturing sector of the Yangtze River Delta, providing a reference for formulating relevant policies and strategies.

The coordinated development between digitization and greenization is of great significance in accelerating the formation of new quality productivity and promoting the high-quality development of the Yangtze River Delta urban agglomeration. On the basis of constructing an analytical framework and evaluation indicator system, this study examined the spatial-temporal change of the coordinated development between digitization and greenization in the Yangtze River Delta urban agglomeration in 2012-2021 by using the longitudinal and transversal pull-difference method, coupling and coordination model, and ESDA (exploring spatial data analysis), and identified its spatial spillover effect by using the SDM (spatial Durbin model). The results show that: 1) From the perspective of time series change, the coordinated development level between digitization and greenization in the Yangtze River Delta urban agglomeration had steadily increased, from nearly uncoordinated at the beginning of the period to an medium level of coordination, and the transfer of state had the effect of path dependence, which makes it difficult to achieve high-quality coordinated development in a short period of time. 2) In terms of spatial distribution, the coordinated development level between digitization and greenization in the Yangtze River Delta urban agglomeration presented a coastal-riverside-inland stepped decline pattern, and at the city level it showed a core-periphery and "V"-shaped distribution. In terms of spatial correlation, the coordinated development level between digitization and greenization in the Yangtze River Delta urban agglomeration showed significant local agglomeration characteristics. High-high type was mainly concentrated in the Shanghai metropolitan area, and low-low type was mainly distributed in Anhui Province. 3) The SDM regression showed that the coordinated development level between digitization and greenization in the Yangtze River Delta urban agglomeration had a significant positive spatial spillover effect, and economic development and scientific and technological innovation were the main sources of the positive spatial spillover effect. The spatial spillover effect showed an inverted "U-shaped" pattern of increase followed by decrease with distance, reaching a maximum at 300 km. Therefore, in the future, we should strengthen the two-way co-progressive effect of digitalization and greening, break down the institutional barriers that impede the flow of digital and green factors and resources, expand the spatial spillover boundaries for the coordinated development of the two, and boost the high-quality integrated development in the Yangtze River Delta region.

The development endowment of urban areas of counties determines the development potential and is the driving mechanism for realizing this potential in county urbanization, which plays a leading role in shaping county urbanization progress. Based on a proposed theoretical framework of county urbanization development endowment, this study selected Southwest China as the research object, and employed the TOPSIS entropy weight method, Kernel density estimation, and the spatial Durbin model to explore the spatiotemporal change characteristics of county urbanization development endowments and mechanisms in Southwest China from 2000 to 2020. The results reveal that: 1) From 2000 to 2020, the development endowment level of county urbanization in Southwest China was relatively low, with a slow growth rate. The spatial distribution gradually evolved from a continuous patch distribution of high in the south and low in the north to a clustered pattern. High-value areas were primarily concentrated around provincial capitals and regional central cities, while low-value areas were mainly located in regions with fragile ecological environment, weak economic foundation, and backward infrastructure. 2) Over the two decades, all five sub-dimensions of county urbanization development endowment in Southwest China exhibited a steady upward trend, ranked as natural ecological environment, endowment, residential environment endowment, public service facilities endowment, non-agricultural industry development endowment, and sociocultural environment endowment. 3) The improvement in the level of county urbanization in Southwest China generated a positive spatial spillover effect on surrounding areas. The development endowment significantly enhanced urbanization development and exhibited boundary effect. 4) The spatial effects of the sub-dimensional endowments showed distinct regional heterogeneity, with the non-agricultural industry development endowment in urban agglomerations and the social and cultural environment endowment in non-urban agglomeration areas having significant negative spatial spillover effects. 5) The urbanization of counties in Southwest China is jointly driven by the non-agricultural industry development endowment, public service facilities endowment, living environment endowment, social and cultural environment endowment, and natural ecological environment endowment.

China is entering an era characterized by severe aging and high population mobility. Identifying regional types of population aging from the perspective of population mobility is essential for the effective implementation of national strategies aimed at addressing aging-related problems across various regions. This study proposed a method for categorizing regional types of population aging by integrating the composite index method of population mobility with elderly population location quotient. Using county-level data from the fifth, sixth, and seventh Chinese censuses, the study identified regional types of population aging across Chinese counties from 2000 to 2020, classifying them into seven categories: aging-in-place, (reverse) accumulation, (reverse) congregation, and (reverse) recomposition. Subsequently, a multiple linear regression model was employed to analyze the factors contributing to population aging in different regional types. The conclusions are as follows: 1) The spatial distribution of aging-in-place counties has significantly contracted, with the Huang-Huai-Hai region, Yunnan-Guizhou Plateau, and southern areas of Zhejiang, Jiangxi, Hunan, and Guangxi identified as the primary regions. 2) The distribution range of accumulation counties has expanded to the Northeast, Chengdu-Chongqing region, mid-Yangtze River Basin, and most part of of Gansu Province, while reverse accumulation counties are primarily located around the Pearl River Delta, Qinghai-Tibet Plateau, and southern Xinjiang. 3) Congregation counties are mainly urban districts within prefecture-level cities or county-level cities, while reverse congregation counties are concentrated in the core areas of the Beijing-Tianjin, Yangtze River Delta, and Pearl River Delta urban agglomerations. 4) Recomposition and reverse recomposition counties are mainly distributed in the northwestern half of the Hu Line, with the number of recomposition counties decreasing while reverse recomposition counties increasing. 5) Population aging in aging-in-place counties is primarily determined by regional socioeconomic development; population aging in congregation and reverse congregation counties is mainly influenced by population inflow; in accumulation and reverse accumulation counties, population outflow has altered the regional aging process; and in recomposition and reverse recomposition counties, the aging process is affected by both population inflow and outflow.

The rapid development of online food delivery services is profoundly shaping urban dining spaces. However, most current studies measure the growth of delivery services from a city-wide perspective and focus on single dimensions, with few studies conducting multidimensional analyses at the neighborhood level. Taking Nanjing City as a case study and drawing on multiple data sources, this research applied spatial statistical analysis methods and found the following: Firstly, at the neighborhood level, the density, diversity, and accessibility of online food delivery services exhibit a gradient spatial distribution pattern, with better development in the central area of the main city. Notably, compared to other two sub-cities, the Dongshan sub-city's central area forms clusters of neighborhoods with "high-high" concentrations of online food delivery services across all three dimensions. Secondly, the development of online delivery services is still influenced by various factors. Both population density and road network density consistently have a positive impact on the density, diversity, and accessibility of delivery services. Neighborhoods located closer to the city center tend to have higher delivery service density and diversity. Those with higher housing prices have access to more diverse delivery options. Additionally, neighborhoods with better accessibility to educational facilities also tend to enjoy higher delivery service accessibility. This study provides empirical evidence for understanding the spatial characteristics and influencing factors of online delivery services at the neighborhood scale, offering support for the formulation of strategies to optimize food service facility planning.

There is a close relationship between the distribution of commercial land and the occurrence of theft, but few studies have explored the differences of population activities on different levels of commercial land and their complex effects on the spatial pattern of theft. Taking ZG City as an example, this study subdivided land use levels based on the distribution characteristics of crowd activities and commercial facilities on commercial plots, explored the impact of different levels of commercial land use and its interaction with commercial facilities on theft, and explored the day and night differences between weekdays and weekends. The results show that: 1) Based on the distribution characteristics of population and commercial facilities, commercial land can be divided into low-, medium-, and high-grade types. After considering the influence of control variables such as active population, social disorder, traffic accessibility, and crime generators and attractors, only medium-grade commercial land can significantly increase the theft rate. 2) The interaction between medium- and high-grade commercial land and the number of commercial facilities inhibits the occurrence of theft, while the interaction between low-grade commercial land and the number of commercial facilities has the opposite effect, which is related to the complex nonlinear relationship between active population and theft. 3) The influence of control variables (active population, social disorder, traffic accessibility, and crime generators and attractors), the grade of commercial land, and their interaction on theft varies from time to time, or is closely related to the operating hours of different types of facilities and the activity preferences of people. The conclusion of this study enriches the research results in the field of criminal geography on the relationship between commercial land and theft, and provides a scientific basis for public security organs to formulate more targeted patrol and prevention strategies.

Human trafficking has existed since ancient times and persists to this day, causing serious damage to family and social harmony and stability. Based on open-source data on the Internet, this study employed statistical analysis and spatial visualization methods to analyze the spatiotemporal characteristics of child trafficking in Henan Province from 1970 to 2018. Furthermore, it exploreed the regional types and formation mechanisms of these crimes. The results are as follows: 1) From 1970 to 2018, the annual variation of child trafficking in Henan Province showed an inverted-"V" shape, high in the middle and low at both ends. It was closely related to fertility policies, anti-trafficking enforcement efforts, and shifts in societal attitudes. In terms of monthly variation, a clear seasonal differentiation was observed, with spring and summer being the peak seasons, largely influenced by climate, agricultural activities, and holidays. 2) The spatial distribution of child trafficking in Henan Province showed significant regional disparities. Hotspot areas include Huaxian County, Yuanyang County, and Lankao County in the northeast, and Erqi District in the central region, while most counties in the northwest, west, and south are low-incidence areas. 3) The regional types of child trafficking in Henan Province were mainly dominated by trafficking in boys, trafficking in girls, and trafficking out boys. Through the study period, the number of boy-inflow-dominant areas has decreased, while the number of boy-outflow-dominant areas has shown an upward trend, and the number of girl-inflow-dominant areas has shown a slight increase. 4) Due to the influence of the family planning policy, regions in Henan Province with severe son preference, poor economic development, and lower educational levels tend to traffic in boys due to restricted fertility, inability to conceive, or the loss of a son, driven by the purposes of "continuing the family line" and "providing old-age support", thereby forming the boy-inflow-dominant type. In contrast, regions with less pronounced son preference often desire "having both a son and a daughter", or some economically disadvantaged men seek to enter marriage by purchasing wives. When faced with fertility restrictions, inability to conceive, or marital mismatches, these regions tend to traffic in girls for the purposes of caregiving in old age and childbearing, forming the girl-inflow-dominant type. The formation of the trafficking out boys is facilitated by a robust buyer's market, sufficient criminal motivation, inadequate regulatory enforcement, market-driven criminal choices, and convenient transportation conditions.

As the impact of global warming continues to escalate, the number and severity of extreme weather events have increased significantly, posing a huge threat to life and property. Existing disaster research often focuses on single events and ignores their inherent complexity and cumulative impacts resulting from their association with other events. Therefore, we urgently need to have a deeper understanding of the patterns and mechanisms of extreme disaster events. To fill this research gap, this study extracted high temperature-heavy rainfall compound events from the meteorological observation data of 1886 stations in China's mainland from 1961 to 2020 and used Theil-Sen median slope estimation and Mann-Kendall trend test to explore their spatiotemporal distribution and change characteristics. The proportion of compound events in single events, the change cycle of compound events, the impact of urbanization on compound events, and the disaster risk assessment of compound events were explored from multiple perspectives. The main conclusions are as follows: 1) The high temperature-heavy rainfall compound events mainly occurred in the eastern monsoon region, and the frequency of events was greatest in the central Sichuan Basin. 2) The frequency of compound events across the country and in each climate zone increased significantly during the study period, especially after 1990. 3) The proportion of compound events in extreme precipitation events increased significantly after 1990. 4) The North China Plain, Huang-Huai, Jiang-Huai, Jiang-Han, Sichuan Basin, and South China coastal areas were at high risk of disasters, and the above areas urgently need to give priority to effective early warning and response strategies to mitigate the impact of compound events.

Precipitation-runoff changes have an important impact on river material (such as phosphorus) transport. With the increasing extreme runoff events in rivers under climate change, there is a lack of systematic research on their impact on total phosphorus (TP) concentration and flux in large-scale river networks. Based on the daily TP observation data of 54 stations in the second-fifth order rivers of the Yangtze River system, this study examined the effects of runoff changes in the eight subbasins of the Yangtze River on river TP concentration and flux changes from January 1, 2021 to December 31, 2022, and analyzed the differences in the effects of extreme runoff on river phosphorus transport under different land use types. The results show that the daily TP concentrations during extreme runoff events in most of the rivers have increased (extreme runoff period > non-extreme runoff period), and the TP flux transported by rivers during extreme runoff events contributed greatly to the annual flux. The contributions of extreme runoff to annual TP flux in low-order rivers of the second-third orders were 66.34%-83.83%, and the contributions in the 4th-5th order rivers were 50.73%-73.19%. Statistical analysis showed that the effects of extreme runoff on river phosphorus transport under different land use types were quite different, and the performance was mixed type > forest and grass type. This study clarified the impact of extreme runoff on water quality changes and material transport in large-scale river networks. The results provide a scientific reference for how river water quality changes in response to climate change and water quality control in large-scale river networks.

The origin and spread of agriculture in the Holocene prompted humans to transition from hunting and gathering to the farming era. The changes in the Earth's surface cover caused by human activities during the early development of agriculture reveal the deep roots of changes in the Earth system over thousands of years, which is of great significance to the study of long-term changes in climate systems and ecosystems. Animal and plant archaeological research can reflect the situation of ancestors using and changing the environment to obtain food, providing favorable conditions for reconstructing early land use and land cover changes. This study used agricultural and archaeological research to explore the grain production, grain consumption, and population size of the ancestors in the middle Holocene, and reconstructed the cropland area and cropland spatial distribution pattern of the southeastern margin of the Qinghai-Tibet Plateau in three periods: 6000-4500 a BP, 4500-3700 a BP, and 3700-2300 a BP. The results show that: 1) The grain production and grain consumption of the ancestors in the middle Holocene showed an upward trend with the development of agriculture and the diversification of crop structure. The average annual grain production was 193, 297, and 450 kg/hm², respectively, and the per capita annual consumption of grain was 220, 250, and 270 kg, respectively. 2) The population size in the middle Holocene continued to increase, at 16222, 24160, and 35885, respectively, which promoted the development of agriculture. 3) Under the pressure of increasing population, the cropland area in the middle Holocene continued to increase, reaching 36982, 40620, and 42289 hm² respectively. 4) The cropland was distributed in narrow strips along the rivers, and the cropland grid reclamation rate was low, mainly at 0-20%. In 6000-4500 a BP and 4500-3700 a BP, the highest reclamation rate of cropland grids was 61.3% and 69%, respectively, and in 3700-2300 a BP, the highest reclamation rate reached 92.7%, and 3.3% of the cropland grids had a reclamation rate of more than 30%.