Yangtze River Delta, as a pivotal region where the coastal axis and the riverside axis intersect, is characterized by complexity, diversity and typicality of the spatial structural evolution. Therefore, understanding its evolutionary pattern and constructing a theoretical model has important theoretical significance and application value. According to the core-periphery structure theory, the Yangtze River Delta can be divided into a core area that is centered on the Taihu Lake Basin and remaining periphery areas. However, due to its location at the junction of the river and the sea, a gateway area has emerged within the periphery area, thus forming a spatial structure that is composed of the core area and the gateway area. In the early period, the core area was centered on Suzhou, and a five-tier central place structure became well established since ancient times. However, the gateway area kept evolving and underwent three main changes: in ancient times, the gateway area was centered on Yangzhou, forming the canal gateway cluster; in the modern age, the gateway area became centered on Shanghai, forming an offshore gateway cluster; and in the contemporary era, the gateway area became centered on Ningbo, forming an oceanic gateway cluster. Their corresponding navigation capacities were 500 t, 10,000 t, and 200,000 t, respectively. Therefore, in addition to the existing central place theory and seaport spatial structure theory, the spatial structure evolution of the Yangtze River Delta presents a new evolutionary model: namely, the fusion evolutionary model of central places and port gateways. According to this model, in the early period, it was an endogenous evolution of the core area's spatial structure, which was in line with Christaller's hexagonal structure; while in modern times, the evolution of the spatial structure of the Yangtze River Delta was no longer dominated by central places, but rather, it became dominated by the gateway areas, making the k = 3 market principle turn into the k = 4 transportation principle. In this way, the Yangtze River Delta provides a globally exemplary empirical case for validating the process test of the central place theory, analyzing functional attributes of urban centrality and gateway, and refining the relevant theoretical model.

With the rapid advancement of science and technology, artificial intelligence (AI) has become a significant force driving scientific development and social progress. In the field of geographical sciences, the application of AI technology is deepening, bringing revolutionary changes to the collection, analysis, and application of big data and spatio-temporal information, and demonstrating innovative and application potential in multiple aspects. This paper systematically reviews the development and application of AI in geographical sciences, providing a detailed introduction to the development trajectories of various AI fields such as machine learning, computer vision, natural language processing, planning systems, and large AI models, as well as their applications in geography. It discusses the problems and challenges of AI applications in geography and provides an outlook on the future development of interdisciplinary research between AI and geographical sciences.

The statistical definition of migration in China is attached with its unique household registration (hukou) system, the migrants so defined are also called the floating population. A new analytical paradigm is needed to deal with the complexity of sub-flows in the floating population. The paper classifies five types of the floating population in census context by referring the UN migration criteria, and constructs a new paradigm for analyzing the floating population in China. As a particular provincial-level region (hereafter province) is concerned, the inflow and outflow people belong to different hukou groups balanced by their own counter-flow, namely, inflow vs back-inflow (both have no hukou of the province), outflow vs back-outflow (both have hukou of the province). With the clue of inter-census migration cohort, a sub-flows model is constructed to identify the inter-provincial migration based on the retention rate. The annual retention rate of the inter-provincial migration cohort from 2010 to 2020 is 88.7%. Based on the provincial retention rates, an all-increment table of population change by province in China is made by modelling simulation. The paper surfaces new characteristics of population growth and inter-provincial migration: (1) Provincial population changes are divided into five types, among which the inflow-leading increase type is mainly found in municipalities and the eastern coastal areas, while the fertility-leading increase type and the fertility-overriding increase type are mainly in the western provinces and the agricultural provinces in the middle, and the outflow-overriding decrease type and the outflow-leading decrease type in Shanxi, Inner Mongolia, Gansu and the northeastern provinces. (2) The mechanical growth of population can be divided into four types: rapid increase, equilibrium, outflow-overriding decrease and dual decrease (both hukou and non-hukou migration are negative). A "W"-shaped mechanical growth rate profile from northwest to southeast is found with the equilibrium belt standing in its middle. (3) Population floating is divided into three types. The counter-flows are highly-correlated: inflow rate and outflow rate are negatively correlated while the inflow-back-inflow and outflow-back-outflow are significant positively correlated. The analytical paradigm and model of floating population in China can be further extended to the study of "citizenship seeking migration" including international migration, and even further to identity migration including migrations with status changing such as enrollment, employment and marriage.

Sustainable development is a significant scientific issue of global concern. Geography, as a comprehensive discipline focusing on the coupled relationship between human activities and the natural environment, provides systematic research and solutions for achieving the United Nations Sustainable Development Goals (SDGs). However, there is currently a lack of comprehensive reviews. This paper summarizes the theoretical framework and research progress of Geography supporting the SDGs and explores its future key research areas. This article indicates that: (1) Geography, in conducting integrated research on human-nature systems and serving regional and global sustainable development processes, has innovatively proposed and developed theoretical frameworks such as social-ecological systems, pattern-process-service-sustainability, metacoupling, and Classification-Coordination-Collaboration. These research frameworks include elements of human-environment system interconnections, process coupling, spatial coupling, and systematic regulation oriented towards SDGs, forming a comprehensive theoretical framework supporting sustainable development research in Geography, also referred to as "sustainable geography theoretical framework". (2) Geography has made positive progress in supporting the United Nations SDGs research in areas such as multi-source data acquisition, localization of indicator systems and multi-scale progress assessment, analysis of inter-target linkage mechanisms, and SDG achievement pathways. Geography provides important theoretical and methodological support for SDG research. (3) Geography and sustainable development-related research mainly focus on climate-ecological crisis response, sustainable utilization of food-energy-water resources, regional development and planning, human well-being and social governance, and the construction of SDG assessment indicators and databases. (4) In future research, there is a need to innovate and develop sub-disciplines of Sustainable Geography, optimize the construction of SDGs indicator systems, develop SDGs assessment and decision-making models, strengthen artificial intelligence geography, deepen research on human-nature system coupling, and promote regional and global sustainable development in the process of advancing innovation in the discipline of Geography.

Understanding the spatial segregation and social integration of immigrants and local residents is highly significant in summarizing the historical experience of Chinese modernization. Additionally, it serves as a crucial foundation for promoting a people-centered new urbanization, fostering spatial fairness and justice, and achieving common prosperity. However, current research on residential spatial differentiation primarily focuses on analyzing the spatial distribution characteristics, differentiation patterns, and indicator calculations of various groups, and has limited investigation into social integration issues. This paper explores this social and spatial differentiation phenomenon in Hangzhou, usingthe initial residence registration information and mobile phone signalling data to analyze the characteristics and mechanisms of living space differentiation. Additionally, this article combines a small sample of questionnaires with a bottom-up exploration of social integration under spatial differentiation. From the research, four key findings emerge: (1) The majority of residents in the city are migrants. There is a clear difference in the distribution of living spaces between immigrants and local residents, with local residents mainly concentrated in the old city area, while the distribution of immigrants is more scattered. Compared to the typical "immigrant city" in the United States, Hangzhou has less spatial differentiation between immigrants and local residents. (2) The residential space differentiation between immigrants and local residents in the city presents a combination pattern of " multi-nuclei, sectoral, concentric zone". However, unlike the centrifugal diffusion trend of the local people in the United States, the local residents in Hangzhou tends to gather towards the center, while immigrants choose centrifugal diffusion and peripheral aggregation. (3) The spatial differentiation of living spaces is mainly caused by the competition for spatial resources between immigrants and local residents under urban expansion. However, behind the phenomenon of "local residents live in the old city", immigrants are no longer a disadvantaged group. Some intelligent new immigrants actively choose to live in high-quality peripheral areas. (4) The integration between immigrants and local residents is satisfactory, but it is more cautious about the issue of intermarriage. Additionally, residential spatial segregation has not had a negative impact on social integration. There are four main reasons for this. To begin with, the majority of the population consists of immigrants, and urban residents no longer pay attention to identity labels in their daily interactions. Besides, there is relatively little cultural difference within ethnic groups, and the assimilation between immigrants and local residents is increasing. And then, interactions between individuals in workplace and third place can alleviate the negative impacts caused by residential spatial segregation. Finally, China's coordinated development and people-oriented social system can also create favorable conditions for social integration.

In the post-Cold War era, the global landscape has evolved towards multipolarity, and the geostrategic behavior of states has gradually shifted away from the traditional binary model of "balancing-bandwagoning" to a more flexible and diverse one called hedging strategy, and it is the current strategy that the countries surrounding the South China Sea have adopted in response to China's actions. By introducing the hedging theory of international relations, we seek to understand, from a geopolitical perspective, how these geopolitical entities employ hedging strategies. First, an analytical framework is constructed to theorize hedging strategy, consisting of driving factors, mediating factors, and strategic choices. Second, the hedging intensity is assessed quantitatively via the geopolitical risk and the relative power index of the countries surrounding the South China Sea. The evolution of it is presented through a bivariate visualization method, and the various hedging patterns are classified by utilizing the quadrant diagram. Finally, both the theoretical framework and quantitative outcomes are validated by analyzing the strategic practices of the study region. We conclude that: (1) the geopolitical risks of the countries surrounding the South China Sea have been "tending to be stable but difficult to achieve" since the beginning of the 21st century, with significant heterogeneity among these countries. The evolution of state relative power exhibits a fluctuating trend, closely linked to U.S. intervention. (2) The hedging intensity of the countries surrounding the South China Sea results from the interaction between geopolitical risk and state relative power, leading to three distinct forms, represented by Vietnam and the Philippines, Indonesia, and Malaysia and Brunei, respectively. (3) The intrinsic logic of the hedging strategies of these countries can be seen as a strategic cognition shaped by their threat awareness and national strategic orientation. This cognition then orientates diverse hedging approaches that guide these countries in applying either cooperative or competitive tools. By understanding the intensity and nature of the strategic hedging by the countries surrounding the South China Sea, we aim to provide a unique vantage point for China's regional governance in the South China Sea.

In the context of the increasingly severe global food crisis caused by multiple external factors, building a more productive, nutritious, resilient, and sustainable food security system to promote the transformation of the agricultural and food system had become more crucial, particularly because it is essential for stabilizing China's overall economic and social development. This paper was based on the perspective of the Nature-Society-Economy complex system. It divided the food security system into three levels: resources and environment, production and supply, and distribution and consumption. This paper constructed an index system based on the three-dimensional framework of Pressure-State-Response, employing provincial panel data from 2000 to 2021 to analyze the spatial and temporal spatial evolution characteristics of China's food security system transformation. A dynamic panel model was adopted to quantify the various driving factors related to the food security system transformation. The research results indicated the following: (1) The comprehensive index of food security system transformation from 2000 to 2021 increased by 97.90%, showing a two-stage change characteristic with a moderate rise from 2000 to 2012 and a rapid growth from 2013 to 2021. The transformation index of the resources and environment and the production and supply subsystems were consistent with the evolution of the comprehensive index of food security system transformation, also exhibiting a two-stage upward trend. The transformation index of the distribution and consumption subsystem showed a downward and then an upward trend. (2) The comprehensive index of provincial food security system transformation increased continuously from 2000 to 2021. The provinces that exceeded China's average shifted from a balanced distribution across the eastern, central, and western regions in 2000 to clustering in the main grain-producing areas in 2021. (3) The food security system transformation is an ongoing endeavor. The rate of urbanization, agricultural financing policies, birth rate, and dietary diversity index can significantly promote the transformation of the food security system. The transformation of the food security system can be seriously hampered by industrialization, relative returns from agricultural production, GDP growth rate, and per capita disposable income.

The driving force behind coordination is that the regional coordination policies can benefit the weak. Since the implementation of the Beijing-Tianjin-Hebei coordinated development policy, its actual effect has been questioned. Some negative views suggest that this policy has only benefited Beijing and Tianjin, but has not promoted the development of Hebei. In response to this question, this paper takes the implementation of the Beijing-Tianjin-Hebei coordinated development policy in 2015 as a natural experiment, using synthetic control method and panel data from 2010 to 2020, empirically evaluates the policy effect and spatial heterogeneity of this policy on economic growth, industrial structure optimization and air quality improvement of Hebei. Results indicate that: (1) The Beijing-Tianjin-Hebei coordinated development policy did not significantly drive the economic growth of Hebei, but promoted the optimization of industrial structure and the improvement of air quality, showing a trend of high-quality coordinated development. (2) The policy effect on prefecture-level cities of Hebei is different due to their distance from Beijing and Tianjin, showing a "center-periphery" diffusion pattern with Beijing and Tianjin as the core. (3) The cities close to Beijing have obtained obvious effect of industrial structure optimization, and the cities close to Tianjin have obtained obvious effect of economic growth. Cities around Beijing and Tianjin are significantly better than cities in southern Hebei in terms of air quality improvement. In the future, we need to view this policy with a new concept of high-quality development, scientifically promote the industrial transfer and undertaking within the urban agglomeration, and continuously consolidate the basic conditions for economic development of Hebei. It is also necessary to achieve spatial equity and adapt to local conditions in the Beijing-Tianjin-Hebei coordination.

With the continuous development and application of information technology, online shopping has emerged as a significant force, bringing immense economic potential. The convenience offered by online shopping, such as the ability to shop anytime, anywhere, and access to a vast array of products, is reshaping consumer habits and expectations. Despite the continued growth of online shopping, the role of physical stores remains significant. Physical stores offer tangible benefits that online shopping often struggle to replicate. These include the ability to see, touch, and try products before purchasing, as well as the immediacy of taking items home without having to wait for shipping. The relationship between online shopping and physical shopping remains a hot topic in academia. Although there have been relevant studies in China, most of them are based on the survey data from individual communities or cities, lacking large-scale and long-term systematic research from a national perspective. Furthermore, there is a lack of heterogeneous comparisons between different regions. Drawing on large-scale time utilization survey data of 29 provincial-level regions in 2017 and 2021, this paper analyzes the spatiotemporal evolution of online shopping behavior and physical shopping behavior of China's residents, and examines the influence of online shopping on residents' physical shopping behavior. The results show that: (1) There are significant spatial differences in the characteristics of residents' online and physical shopping behaviors. The standard deviation ellipse of online shopping and physical shopping behavior shows an obvious "northeast-southwest" distribution pattern, with the gravity center gradually shifting northward during the study period. (2) In 2017, online shopping had a significant complementary effect on physical shopping. But in 2021, both complementary and neutral effects coexisted. (3) There are significant differences in the impact of online shopping on physical shopping between urban and rural residents, and residents among different regions. There is also a coexistence of complementary effects and neutral effects. This paper clarifies the relationship between online shopping and physical shopping in China, provides an in-depth understanding of the changes of urban space in the internet era, and helps promote the spatial transformation of physical commerce.

The advent of information intelligence and spatiotemporal big data have significantly broadened the scope of application for geographic information systems (GIS), presenting both opportunities and challenges in the modeling of geographic scenarios. Current paradigms for organizing spatiotemporal data and conceptualizing spatial cognition predominantly rely on a bottom-up approach, which was demonstrated with limitation on low cognition and the fragmented representation of geospatial objects. This is a noteworthy research issue facing the Big Data era, namely the design of new representation models for the integration of objects and knowledge, as well as the collaborative computation of models and objects. This study, inspiring from Leibniz's relative spatiotemporal perspective, establishes an object space-based approach for organization and management of geographic scenarios. The concept of object space was proposed by reviewing the historical evolution of geographic scenarios representation model and literature work on mainstream research domain. Object space is the space of influence of an object, both the inner space of the object and the space of its surroundings. It includes pan spatiotemporal object, object space relationship, calculation and analysis process, which represents object, knowledge and model. For representing and management of object space, a hierarchical model was developed to organize pan spatiotemporal objects according to business requirement and spatial scale. Further, a network model was denoted to represent object space relationship and knowledge, in which node is the objects, and edge is the space relationship. Then, a model classification method based on functional and computational ability was used to organize calculation and analysis process models. Thus, a highly integrated and synergistic "data-knowledge-model" organization and management model was established. The proposed approach was applied in monitoring soil moisture in high-standard farmland in Shandong, which included 44 pan spatiotemporal objects, 2 object space relationship network models and 5 calculation and analysis process models. The results demonstrated its efficacy and feasibility in designing and implementing high-standard farmland intelligent automatic irrigation and drainage systems, thereby offered technical support for advancing theoretical research and expanding practical application in geographic scenarios.

In the wake of unprecedented global urbanization, an alarming trend of shrinking cities has emerged worldwide, presenting a profound challenge to conventional urban-regional planning approaches, primarily centered on growth scenarios. This trend has also bestowed upon Chinese geographers and urban and rural planning practitioners a new mandate in this evolving era. One region that exemplifies this predicament is Northeast China, experiencing the most severe population decline and the highest concentration of shrinking cities in the country. How to rationally recognize and properly deal with this phenomenon (or problem) of regional urban shrinkage has become the core scientific issue to be focused on in the comprehensive implementation of regional coordinated high-quality development, Chinese-style modernization of common prosperity for all and all-round revitalization of Northeast China in the new era. This paper delves into a logical speculation and practical discussion to understand the underlying causes and implications of regional urban shrinkage in Northeast China: Initially, it examines the original concept of regional shrinking cities within the context of urbanization, critically evaluating the rationality of such shrinkage in light of the broader national strategic objectives. Subsequently, the generation logic of regional urban shrinkage in Northeast China is explored through three key factors: the "pull" effect of regional spatial correlation, the "extrusion" effect of urban shrinkage at a regional level, and the "catalyst" effect of transportation and communication technology development in reducing the cost of factor flow. Moreover, this study draws on the market-led shrewd contraction theory and the government-led vitality regeneration governance logic. It takes into account the governance objectives of achieving "regional coordinated high-quality development, people-oriented new urbanization, efficiency and fairness, and comprehensive security concept". With a systematic perspective that considers scale heterogeneity, development context relevance, factor differentiation, and multidisciplinary integration, the paper outlines a governance model and strategy for addressing regional urban shrinkage in Northeast China. By emphasizing the alignment of governance approaches with national development goals, this research underscores that regional urban shrinkage goes beyond a mere outcome of market-driven population migration. The presence of underlying "market failures" severely impacts the vision of the five major securities (national defense, food, ecology, energy, industry) advocated by Chinese President Xi Jinping for the Northeast China region. The findings of this study offer valuable insights to guide Northeast China's pursuit of high-quality development and contribute to the region's revitalization efforts.

The relocation of urban administrative centers plays a crucial role in optimizing urban spatial structure and advancing the modernization of the national governance system and capabilities. A thorough analysis of the spatiotemporal patterns, driving mechanisms, and development trends of administrative center relocations in China is not only a practical necessity for supporting the modernization of national governance but also a foundational requirement for the standardization and scientific advancement of administrative center relocations. This study utilizes spatial analysis methods to comprehensively examine the relocation of administrative centers in cities at or above the prefecture level in China from 1978 to 2022. The results show that there have been 81 instances of administrative center relocations across the country since the implementation of the reform and opening-up policy in the late 1970s. These relocations peaked between 2003 and 2007 and showed significant regional disparities. These relocations are predominantly short-distance and mainly aimed at promoting the development of new urban districts, often resulting in a separation from the geographical center. The relocation of urban administrative centers is a complex process influenced by an interplay of multiple factors, including national policies, governmental guidance, power distribution, resource reallocation, and planning adjustments. The regulatory role of national policies and the guidance provided by city governments are critical components in this multidimensional negotiation. In the context of the current strict national regulation of administrative division adjustment, the relocation of urban administrative centers will continue to reinforce traditional driving factors while aligning with socio-economic and technological shifts, presenting new directions driven by ecological governance, transportation development, and the evolution of innovative industries. In the future, it is essential to carefully evaluate the necessity of relocation while maintaining the fundamental stability of administrative centers. Implementing top-level design for administrative center relocations, adhering to standardized approval processes, and rigorously evaluating the rationale are key to promoting all-encompassing urban advancement. This study provides a reference for scientifically understanding the patterns and intrinsic mechanisms of urban administrative center relocation.

Fostering coordination among the economy, society, resources and environment is a crucial requirement for high-quality urbanization. This work developed an indicator system for the degree of coordination involving urbanization-economy, urbanization-society, urbanization-resources and urbanization-environment based on the dynamic evolution of urbanization and time series analysis. Using counties as the statistical unit, the study investigated the spatiotemporal evolution process and impact mechanism of the multidimensional coordinated urbanization from 2000 to 2020 on the Qinghai-Tibet Plateau. Urbanization-resource coordination was found to be the highest overall. The levels of coordination between urbanization-economy and urbanization-society were relatively low, whereas the coordination degree for urbanization-environment was moderate and essentially consistent. The measurements described above showed a convergent tendency between 2000 and 2020. The levels of coordination between Qinghai and southern Gansu generally decreased, and the rate of urbanization outpaced that of economic growth, placing significant strain on the environment and resources. The overall degree of coordination improved in Xizang, western Sichuan, and Yunnan, despite the fact that their individual coordination levels were on the decline. The regression findings showed that the industrial development, which is primarily influenced by the industrial structure, is a crucial element in enhancing the degree of urbanization-economy coordination. The financial capacity of the government has a significant impact on the degree to which urbanization and society are coordinated. As the scale of fiscal spending expands, it correspondingly rises the degree of coordination. Furthermore, economic development and government fiscal spending have a negative effect on the coordination degree of urbanization-resources and urbanization-environment. When industrial proportion and government fiscal spending capacity increase, the coordination degree of urbanization-resources and urbanization-environment declines, indicating the plateau's dilemma between economic development and environmental protection. However, if the industrial enterprises are primarily larger than the designated size and the scale of the center town agglomeration is enormous, it is conducive to strengthen the coordination degree of urbanization-resources and urbanization-environment.

Waterlogging, water pollution, black and odorous water, and riverine and lacustrine ecological degradation are the main water problems faced by China's cities, which have become one of the key obstacles to the green development of the Yangtze River Economic Belt. In-depth understanding of the evolution of the water system in the process of urban development and the mutual influences between the elements, clarifying the formation mechanism of the urban water problems, and constructing an integrated treatment technology system of the urban water system are the fundamental ways to solve the complex urban water problems. Aiming at the abovementioned urban water problems, this paper summarizes the concepts and characteristics of the urban water system from a systematic perspective of the multiple processes coupled with each other in the water cycle and proposes a key technology system for a systematic solution to the urban water problems, which are demonstrated with the treatment examples of the urban agglomeration in the Yangtze River Economic Belt in 2016-2022. The demonstrative applications show that the pumping stations and sponge measures can effectively reduce the severely inundated area of Wuhan city in extreme rainfall events and eliminate the waterlogging points in the Chengdu-Chongqing urban agglomeration; the proposed microbial-botanical-hydrodynamic integrated synergistic regulation and control technology can significantly enhance the removal efficiency of the nitrogen and phosphorus level in typical black and odorous water bodies of Wuhan city; the proposed source control-path dissipation-terminal regulation comprehensive ecological treatment system for urban rivers and lakes decreased the water eutrophication level significantly in the Lianghe River basin of Chongqing city; with the implementation of the abovementioned treatment technology system, the green development index of the urban agglomeration in the middle reaches of the Yangtze River increased by an average of 4.8%. This study provides theoretical and technical support of urban water system for the major strategies of the green development of the Yangtze River Economic Belt.

The physical geography and hydroclimatic conditions in the arid region of in northwestern China leading to diverse flood-generation mechanisms. Under the influence of global and regional climate change, the spatiotemporal variation of floods and flood-generation mechanism in this region is still unclear and restricts flood prevention and mitigation and the implementation of the Belt and Road Initiative in the major regions. Based on the series of the annual maximum flood peak discharge in 58 river basins in the study area from 1961 to 2017, we analyzed and revealed the mechanisms, spatial distribution and interannual variation characteristics of flood in the basin in the past 60 years based on statistical tests and machine learning approaches. The results show that the frequency of extreme floods and the annual maximum flood peak discharge magnitude are increasing, with the maximum increase in the frequency of extreme floods at about 0.84 times/10 years, and the maximum increase in the annual maximum flood peak discharge magnitude at about 29%/10 years compared with the multi-year average, and the largest increase is mainly observed in the eastern Tianshan Mountains and the Qilian Mountains. There are three main flood generation mechanisms, i.e., rain (R), snow (S) and mix (M), the frequency of R and M floods increased significantly, while the frequency of S floods decreased. The contribution of flood mechanisms transformation to the increase of annual maximum flood peak discharge magnitude can reach up to 38%, which is significantly higher than the contribution of a single hydrometeorological factor such as precipitation. The results of this study emphasize the importance of attributing and predicting the changes of flood characteristics in geographically complex region from the perspective of flood mechanisms. Engineering hydrological design in the changing environment also needs to consider the influence of the heterogeneity of flood samples caused by different flood mechanisms on the flood frequency analysis, so as to provide scientific support for flood risk management and response in the basin.

The new wave of technological revolution driven by artificial intelligence (AI) has become a competitive advantage pursued by countries worldwide, and it is also expected to bring about significant innovations in urban geography. This paper reviews the development trajectory of AI and proposes a conceptual model of the urban human-environment system oriented towards AI. It systematically outlines and summarizes the involvement of AI in urban geography research from four perspectives: data representation, scenario applications, spatial transformations, and urban development. Additionally, it identifies the challenges, contexts, exploration paths, and future prospects faced in the intelligent transformation of academic disciplines. The study finds that: (1) The interactions between elements within the urban human-environment system oriented towards AI are becoming increasingly complex. (2) The trend of AI becoming a primary tool in urban geography research is increasingly evident, offering high efficiency, low cost, and strong learning capabilities in data processing. This has significant implications for spatial perception and intelligent decision-making. AI has sparked spatial transformations, not only creating complex virtual spaces but also reconstructing social spaces. Additionally, AI supports the development of smart cities and the establishment of cutting-edge urban application platforms. (3) Urban geography research in the context of intelligent transformation faces challenges related to data and technology, as well as the broader contexts of global and local changes, technological ethics, and the development of humanistic values. Future development paths could explore overcoming technical barriers, focusing on urban spatial construction and governance, and emphasizing the research on the effects of multiple intelligence shifts. The discipline urgently needs comprehensive transformation and upgrading.

Permafrost is highly sensitive to global changes, and it is important to reveal climate and environmental changes in permafrost regions using vegetation succession. Based on palynological evidence and AMS¹⁴C dating from a sediment core, vegetation succession and climate history in the Late Pleistocene of the Mohe Basin (MHB) in the Greater Hinggan Mountain permafrost region was reconstructed. The response of vegetation to environmental changes was further investigated. Results showed that pollen assemblages effectively reflect the vegetation composition in the MHB and surrounding mountainous areas. Based on the relationship between key regional vegetation and climate indicators, vegetation has undergone significant historical changes: from 30.0 to 27.1 ka BP, a meadow wetland landscape showed a cold and humid climate; from 27.1 to 20.5 ka BP, a coniferous forest-grassland landscape indicated a relatively cold and arid climate; from 20.5 to 11.3 ka BP, there was a transition from coniferous forest wetlands to mixed coniferous-broadleaved forest wetlands, indicating the beginning of a warming although the climate remained cold and humid; from 11.3 to 1.9 ka BP, a mixed coniferous-broadleaved forest wetland landscape demonstrated a warm and humid climate; from 1.9 ka BP to the present, a coniferous forest wetland landscape revealed a cool and humid climate. A comparative analysis showed that factors influencing vegetation succession include not only climate conditions related to latitude and land-sea location but also regional factors caused by permafrost itself. Vegetation succession exhibited different response mechanisms to permafrost changes during glacial and interglacial periods. During the Last Glacial Maximum, permafrost expansion benefited the growth of cold and drought-resistant terrestrial herbs with shallow roots such as Artemisia and Chenopodiaceae, leading to the expansion of arid grasslands. During the Holocene Megathermal Period, permafrost degradation provided favorable habitats for vegetation, and also facilitated the formation and expansion of wetlands, promoting the extensive proliferation of aquatic plants, ferns, mosses, and trees, forming a forest wetland landscape. Therefore, permafrost presence enhances the effects of water and heat under different climate conditions on vegetation, making vegetation more sensitive to environmental changes in permafrost regions.

Human settlements geography leverages the comprehensive strengths of geography that are recognized both in China and internationally. Therefore, human settlements geography represents the mature evolution of the discipline of geography through interdisciplinary integration. Human settlements geography directly responds to the public's aspirations for superior human settlements and fulfills critical national priorities. Compared to urban, economic, and behavioral geography, human settlements geography's theoretical frameworks, practical applications, and integrative development remain under-explored. To advance this field, delineating its theoretical underpinnings across the following five key dimensions is essential: foundational theories, theoretical frameworks, geographical scales, research paradigms, and thematic narratives. Central to the discipline is the exploration of human-settlements relationships, which are approached through both "three dimensions" and "three elements" perspectives. By capitalizing on the unique interplay of "three states", the discipline advocates for an open integration model, proposing a novel pathway for human settlements geography, which is poised to navigate three pivotal avenues: engaging with new scientific inquiries, adopting innovative data and methodologies, and embracing progressive development concepts. This strategy aims to transition human settlements geography from a specialized intersection of interdisciplinary study to a more encompassing and influential field, marking its significance as a major branch of geography and a substantial discipline. The synthesis of theoretical depth, practical relevance, collaborative integration, and strategic development in human settlements geography seeks to catalyze cross-disciplinary synergy and paradigmatic shifts. It aims to meet residents' diverse needs, support evidence-based national development policies, and enhance China's role and authority in shaping global human settlement policies, highlighting the country's dedication to fostering sustainable and habitable human settlements.

In the past 40 years since the theory of "pole-axis system" was put forward, its connotation has been continuously enriched, which has profoundly influenced the theoretical and empirical research in multiple disciplines. The theory has also greatly contributed to China's spatial development of national territory, planning and construction of urban system, and layout of major productive forces. In the new era, China's major regional strategies have profound scientific connotations, yet they still need to overcome blockages such as loose connections within and between urban agglomerations in the course of practice. In this sense, the framework of multi-dimensional proximity from the perspective of evolutionary economic geography can be instructive, since it further focuses on the dimensional linkages of cognitive proximity, technological proximity, relational proximity, and social proximity. Thus, in the context of "dual circulation" strategy, China's territorial space development should be further guided by the theory of "pole-axis system" as well as the framework of multi-dimensional proximity, accelerating the cultivation of new quality productivity, constructing a resilient network of inter-regional industrial collaboration, and comprehensively empowering regional high-quality development.

Amid the increasing global uncertainties, studying the risk structure and resilience level of global supply chains for agricultural products highlights their importance. It not only provides China with a scientific foundation for better utilizing international markets and resources and ensuring the safety of agricultural product imports, but also promotes the development of risk resilience management theories and methods for typical products across geographical spaces, thus expanding research in resource geography. This study builds a framework that consists of three sectors (export sectors, logistics and transportation sectors, and import sectors) and four stages (supply, procurement, transportation, and demand). Using two-stage DEA and CoDEA models, it evaluates the supply chain risks and resilience of soybeans, which is the typical import-dependent agricultural product in China. The findings indicate that: (1) The risk of China's imported soybean supply chain increased from 2000 to 2020, with risks predominantly from the demand and procurement stages. By contrast, the supply and transport stages are less risky but significantly increased. Trade relations with exporting countries and economic policy uncertainty are the main long-term risk factors that threaten the security of soybean import supply chains. (2) China's soybean supply chain from Brazil is more resilient than that from the US and Argentina, suggesting great potential for improving supply chain cooperation with Brazil. (3) Making the distinction between short- and long-term threats is necessary for managing the risk resilience of the global soybean supply chain. Improving the capacity to react to sudden hazards represented by trade restrictions, maritime obstructions, and trade sanctions should be the priority in the short term. Long-term exploration of system construction and strategic layout optimization is necessary to improve the discursive power of the supply chain.

This paper reviews the social background of "pole-axis system" theory and the "T-shaped" land development and economic layout framework in China, especially the objective conditions that the country cannot implement another "strategic shift" of national development priorities, and the academic contribution of economic geography serving to national strategic development, as well as some concepts, ideas, knowledge and methods to achieve this goal. According to the significance and the scholars' comments of this theory and model in national practice, this paper describes the growth course and academic responsibility of an economic geographer to inspire the academic community to uphold the rigorous attitude of seeking truth from facts to make greater contributions to the construction of socialism with Chinese characteristics in the new era.

Global protected areas have been widely recognized for their conservation effectiveness, but are still facing problems such as insufficient coverage, ecosystem representation and species protected progress. At the same time, most of the protected areas are small, poorly connected and threatened by climate change and human activities. This highlights the urgent need to systematically improve the stability and conservation effectiveness of protected areas through the expansion and connectivity management of protected areas. Although some studies have tried to realize the connectivity of protected areas through ecological corridors, a unified concept has not been proposed, and a general consensus of the construction and optimization framework is lacking. Through a systematic review of relevant studies, the definition and classification system of protected area connectivity network, as well as the construction and optimization framework are put forward. According to the conservation objectives, protected area connectivity network can be divided into three categories, namely biological migration network, structural stability network and climate connectivity network. Different methods can be used to construct and optimize protected area connectivity network according to the framework of "expansion and optimization of protected areas - construction of landscape resistance surface-extraction of ecological corridors-connectivity network optimization". Current research focuses on constructing short-term effective network from a static perspective, emphasizing direct ecological benefits while ignoring conservation input and social value. In future research, dynamic connectivity network should be constructed from a dynamic perspective based on long time series data. The long-term effectiveness of the connectivity network should be safeguarded against the future threats of land use change and climate change. The optimal scheme of connectivity network construction and optimization should be determined based on cost-benefit analysis, considering the trade-off of different conservation objectives and social development. Finally, the social added value of the connectivity network should be enhanced to gain more support.

Metropolitan areas are pivotal in driving national economic growth, advancing harmonious regional development, and participating in competitive international collaboration. Consistent with international consensus, China's planning policies define metropolitan areas as a one-hour commuting circle. Simultaneously, these planning protocols particularly highlight the importance of industrial specialization and intercity collaboration, with the objective of developing modern urban agglomerations characterized by a well-defined spatial structure, complementary urban functions, and an integrated industrial division. This study uses the 2017 intercity input-output table analysis to examine patterns of industrial division and functional synergy in Chinese metropolitan areas. The findings are as follows: (1) From the perspective of industrial division and functional synergy, Chinese metropolitan areas can be categorized into four distinct spatial structures: the single-center dispersed structure, the core-periphery structure, the peripheral expansion structure, and the multi-center network structure representing an advanced phase in the spatial evolution of metropolitan areas. (2) The spatial network of industrial chains in Chinese metropolitan areas is predominantly governed by the flow of processing and manufacturing links. There is a substantial gap in the processing and manufacturing links between the Beijing and Tianjin metropolitan areas compared to similar types of metropolitan areas, and there is considerable potential for enhancing the productive service links in the Guangzhou, Chengdu, and Changsha-Zhuzhou-Xiangtan metropolitan areas. (3) The essence of transforming Chinese metropolitan areas into functionally complementary industrial cooperation areas is to further refine the spatial network of the industrial chains, strengthen functional synergy between cities, and encourage spatial integration in the metropolitan areas. (4) Single-center dispersed structure metropolitan areas, including Shijiazhuang, Chengdu, Wuhan, and Changsha-Zhuzhou-Xiangtan should initially transition toward a core-periphery structure. In contrast, peripheral expansion structure metropolitan areas such as Nanjing and Hangzhou metropolitan areas, and core-periphery structure urban agglomerations such as Tianjin, Shenzhen, Guangzhou and Beijing metropolitan areas should progress toward a multi-center network structure.

Utilizing location data from USPTO patents spanning 1790 to 2022, this study incorporates theories from complexity science, lifecycle analysis, and geographical nature. It employs methods including urban scaling laws, scale-adjusted metropolitan indicators, and geographic detectors to construct a performance index for United States science and technology innovation (STI) centers, and analyze their spatiotemporal pattern evolution and driving mechanisms. The results reveal that: (1) Innovation scaling laws across cities have evolved into significant super-linear relationships, indicating that larger cities have higher per capita innovation outputs, thus demonstrating a pronounced scale-increasing effect of STI. (2) The performance index facilitates cross-scale comparisons of urban STI capabilities, illustrating the complete lifecycle of STI centers from incubation, expansion, decline, to revival. Throughout the study period, San Francisco CSA progressively surpassed New York CSA, Boston CSA, and Chicago CSA, becoming a leading STI center in the United States. (3) The spatial distribution of the performance index for US STI centers reveals a "north-superior, south-inferior" pattern. Factors of second nature, such as urbanization, internationalization, and socio-economic development, along with urban polycentricity, positively influence the performance index. In contrast, population density and first nature factors like climate and topography negatively correlate with the performance index. Under the influence of path dependence and cumulative causation, the performance of US STI centers exhibits a "Matthew effect", exacerbating the north-south divide.

Rural attraction is an important indicator of the functions of the rural regional system during flow situations. This theoretical topic in rural development has been discussed within multiple disciplines, but lacks systematic research. Nevertheless, it has become a cutting-edge theoretical research topic in the field of rural geography. Following the research progress and theoretical foundations of rural attraction, this paper constructs a theoretical framework for rural attraction from a geographical perspective, and explains five of its most important issues. (1) The research literature on rural attraction has shifted from fragmented elaborations on the qualities of attractive villages and the unidimensional analysis of rural attraction to the exploration of its concept, mechanism, and evaluation system in terms of urban-rural interactions. The theories underlying the rural regional system of human-environment interactions, gravity, population migration, and attraction property rights, can provide a theoretical foundation and inspiration for the research on rural attraction. (2) Focusing on scientific issues in rural attraction, such as "what is-how-why-how to", and moving toward the framework goal of "theoretical innovation, serving practice, and methodological guidance," a theoretical framework for rural attraction is constructed with the support of spatiotemporal considerations, a comprehensive theoretical paradigm, and the methods used in the field of rural geography. (3) Five important issues experienced during efforts to improve rural attraction were analyzed. First, we analyzed the conceptual connotations of rural attraction based on the background of rural regional systems and spatial interactions from the perspective of spatiotemporal processes. Second, we constructed a measurement framework for rural attraction based on these conceptual connotations and evaluation principles. Third, we identified the regional types and spatial structures of rural attraction from the perspectives of spatial correlations and scale transformation. Fourth, following the theories of human-regional system of human-environment relationship and scale transformation, we explored the mechanisms of rural attraction's endogenous development and exogenous embedding processes. Fifth, considering historical processes and spatial heterogeneity, we explored the pathways and policy insights for enhancing rural attraction. Overall, this research attempts to construct a "what is-how-why-how to" research framework for rural attraction based on a comprehensive "spatiotemporal human-environment" perspective. This study aims to deepen and expand the theoretical research on rural attraction, in addition to providing theoretical references and policy insights for the implementation of rural revitalization strategies in the construction of harmonious and beautiful rural areas.

Urban housing prices are influenced by various factors, encompassing macroeconomic conditions, urban planning strategies, and the specific characteristics of housing. These elements play a crucial role in shaping urban planning and development. Nonetheless, the regression analysis depicting the interplay between urban housing prices and their influencing factors reveals significant spatial non-stationarity and intricate nonlinear characteristics. Addressing the limitations of Euclidean distance in delineating spatial proximity for housing price modeling and the challenges encountered by the geographically weighted regression model (GWR) in capturing complex nonlinear features, this study introduces travel duration (TD) as a spatial distance metric and integrates it with a spatially weighted neural network to establish a geographically neural network weighted regression model with travel duration (TD-GNNWR) to estimate housing prices. In an empirical experiment using 2019 second-hand house data in Wuhan, the TD-GNNWR model demonstrates a 16% enhancement in fitting accuracy compared to the GWR model. The TD-GNNWR model notably enhances accuracy within sparsely sampled regions and better mimics their spatial distribution. Moreover, it adeptly captures spatial non-stationarity, offering a more precise elucidation of factors influencing housing prices in Wuhan and the resultant spatial discrepancies stemming from urban zoning. Our findings underscore the comprehensive impact of various factors on housing prices in Wuhan, such as building characteristics, neighborhood attributes, and transportation accessibility. Factors like greening rates, property fees, proximity to primary schools, universities, and public transportation exert substantial influence on housing prices in Wuhan, with varying directions and strengths across different areas, signifying clear spatial differentiation. The TD-GNNWR model clearly elucidates the mechanisms underlying housing price determinants while illustrating the inherent spatial non-stationarity, which is beneficial for urban planning departments and real estate managers in policy formulation, macro-control, urban planning, and investment decision-making. This work can also serve as a valuable reference for tackling challenges in urban analysis and modeling, thereby enriching methodologies within real estate research.

With the acceleration of urbanization, traditional large-scale remote sensing image and economic statistical methods cannot accurately depict the dynamics of urban economic development from a fine scale. Streetscape images can reflect the material spatial features of the urban built environment. And based on this, economic development indicator (EDI) can be predicted at a finer scale. The study proposes an improved Deeplabv3_MEP semantic segmentation model for streetscape images to extract the percentage of streetscape elements. Then, graph neural network (GCN) and convolutional neural network (CNN) are used separately with streetscape factor index and streetscape images as inputs to predict EDI. And the XGBoost model is used to analyze the driving factors of EDI. The carbon sinks are calculated and a Lasso regression model is constructed to evaluate the effectiveness of green economic development in administrative regions. The results show that: (1) At the city-level division scale, the economic indicator of Jinan city shows a trend of high concentration towards the city center and a gradual decrease towards the outskirts. (2) At the district-level division scale, Lixia district has the highest level of economic development. And the development level in sporadic areas in the east is very high, while that in other areas is lower. (3) At the street-level division scale, the closer the street is to the district or county center, the higher the average income level of residents, and the closer the street is to the city center, the higher the average income level of residents. (4) Driving factors such as wall, sky, road, and car, contribute more to EDI, while factors such as pole and motorcycle contribute less, with bus being the lowest. (5) There is a phenomenon of mismatch between the green economic development index and the level of economic development.

Evolutionary economic geography has proposed the principle of relatedness. According to the degree of relatedness, the regional industrial development paths can be divided into related diversification and unrelated diversification. However, the current studies neglect the symmetrical nature of relatedness. According to the degree of symmetry between two related industries, related diversification can be divided into symmetrically related diversification and asymmetrically related diversification. Using Chinese industrial enterprises database from 1998 to 2012, this paper investigates symmetrically related diversification and asymmetrically related diversification's relationship with regional economic complexity. The result shows that: (1) The regional industrial development paths are dominated by related diversification rather than unrelated diversification. The number of related new industries in China accounted for about 60%-70% of the total number of new industries from 1998 to 2012. In terms of related diversification, positively asymmetrically related diversification takes the largest part, while symmetrically related diversification takes the second largest part. The number of positively asymmetrically related new industries accounts for about 60% of the total number of related new industries, and the number of symmetrically related new industries accounts for about 35% of the total number of related new industries over the time period from 1998 to 2012. (2) Industries with higher technological complexity show stronger symmetry in their related diversification, while industries with lower technological complexity show stronger positive asymmetry in their related diversification. (3) Regions with higher economic complexity usually have more unrelated diversification and its related diversification shows stronger symmetry. Regions with lower economic complexity usually have more related diversification and this related diversification shows stronger positive asymmetry. This study can contribute to the development of the principle of relatedness in evolutionary economic geography and provide suggestions for policymakers in terms of the industrial upgrading of regions.

The nonlinear relationship and spatially heterogeneous relationship between environmental factors and criminal activities are the main reasons for both the theoretical and empirical divergence, but the relevant analysis remains fragmented and faces limitations such as linear relationship hypothesis, collinearity problems and omitted variable bias. This study uses Gradient Boosting Decision Tree (GBDT) algorithm and Shapley Additive Explanation (SHAP) interpreter in machine learning to systematically reveal the nonlinear and spatially heterogeneous relationships between 48 built and social environmental factors on violent crime in Beijing. Our research has revealed the existence of seven distinct types of nonlinear relationships between environmental factors and violent crime, each exhibiting unique trends in the direction of influence and marginal effects. Furthermore, we have found that the association between environmental factors and violent crime exhibits varying degrees of spatial heterogeneity. By utilizing K-means clustering analysis, the entire area can be segmented into six distinct regions, each characterized by different critical criminogenic factors. These findings suggest that the applicability of crime geography theories, such as the classification of crime generators, attractors, and inhibitors based on crime pattern theory, the validity of street eye theory and defensible space theory, and the impact of social attributes as proposed by social disorganization theory, may depend on the value range of environmental factors and differ across locations. In light of these findings, it is recommended that crime prevention strategies shift from universal to targeted approaches, wherein public resources are allocated to specific value ranges of environmental variables and prioritized regions.

Major productive forces are crucial to the country's long-term stability and sustained prosperity, and are also a powerful means of improving economic efficiency, promoting coordinated regional development, and strengthening international competitiveness. This paper summarizes the layout of China's major productive forces and their spatial patterns in different periods by collecting multi-source data such as historical documents, regional socio-economic statistical data and remote sensing of light, and borrowing technical methods such as MCR model, kernel density analysis and standard deviation ellipse, etc. The main conclusions are as follows: (1) The layout of China's major productive forces follows the law of economic geography agglomeration and diffusion cycle evolution, and has experienced the evolution of balanced development - decentralised development - centralised development - coordinated development-high-quality complementary development. This is manifested in the concentration of 156 projects to a few geographic spaces in the western region of China, dispersion in the central and western regions during the Third Front Movement, concentration along the eastern coast, and a gradient advancement toward the inland. However, the focus of development has always been in the southeast region along the Hu Huanyong line. (2) The results of the spatial pattern simulation of major productive forces follow the theory of regional development stages. During China's high-level development process, different spatial patterns have emerged successively: points (core poles), point-axis, and point-axis system (network), forming a multi-level pole-axis system with a "T" main framework along the coast and the Yangtze River, supplemented by other central cities and transportation arteries, in order to promote the balanced development of territorial space. (3) The main influencing factors of the development layout of China's major productive forces vary from time to time, with the geo-environment influencing the spatial layout in the early stage, and then the combined force of national strategies, policies and markets; GTWR further reveals that there is significant spatial and temporal heterogeneity in the factors influencing the development layout. The GTWR further reveals that there is significant spatial and temporal heterogeneity in the factors affecting its development layout. This study focuses on the layout and spatial patterns of the major productive forces, which can provide practical references for optimizing the layout of major productive forces and constructing a regional economic layout and national spatial system with complementary advantages and high-quality development.