Most Viewed

  • Published in last 1 year
  • In last 2 years
  • In last 3 years
  • All

Please wait a minute...
  • Select all
    |
  • Theoretical and Methodological Exploration
    FANG Chuanglin, SUN Biao
    Acta Geographica Sinica. 2024, 79(6): 1357-1370. https://doi.org/10.11821/dlxb202406001

    New quality productive forces are advanced productivity that is freed from traditional economic growth mode and productivity development paths, features high-tech, high efficiency and high quality driven by technological innovation in the new era. From the geographical perspective, developing new quality productive forces is the ability to coordinate new human-earth relationships in the Anthropocene, where human activities dominate, promote the harmonious coexistence of humans and nature, transform green waters and mountains into gold and silver mines, drive high-quality development and layout, and comprehensively implement the construction of a beautiful China. Geography focuses on studying the emergence and development process, formation and evolution characteristics, spatial organization patterns, and regional differentiation laws of new quality productive forces driven by innovation, so as to promote the human-earth system to enter the ecological civilization stage of highly coupled and harmonious coexistence between humans and nature. Compared with traditional industries, the evolution of new quality productive forces has experienced a fluctuating process of evolution from low-quality productivity to medium-quality, medium-high-quality, and then to high-quality productivity, accompanying the emergence of continuous technological revolutions and industrial revolutions. They exhibit basic characteristics such as high coupling, deep integration, super correlation, rapid iteration, and spatial differentiation. The pivotal directions propelled by the drive of new quality productive forces for geographical research encompass the following: re-coordinating human-earth relationships to foster novel harmonious coexistence conducive to the realization of a beautiful China; restructuring industrial systems to align with the new quality productive forces, facilitating profound industrial transformation; reallocating geographical elements to establish a novel mechanism that harmonizes natural, humanistic, and data-driven components; reshaping spatial pattern to engender a fresh spatial paradigm wherein new quality productive forces and traditional industries are integrated deeply; rebuilding ecological environment to leverage them as green engines of productivity, thus enhancing the intrinsic value of ecological capital; revitalizing geographical science through the refinement and updating of theories and methods, thereby constructing a modern disciplinary landscape of geography.

  • Theoretical Exploration
    LI Yuhang, XU Zhiwei, LIU Yanhua, ZHANG Yuhu, SUN Fubao
    Acta Geographica Sinica. 2024, 79(10): 2409-2424. https://doi.org/10.11821/dlxb202410001

    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.

  • Theory & Methodology and Discipline Development
    ZHANG Baiping, YAO Yonghui, LIU Junjie, LI Jiayu, JIANG Ya
    Acta Geographica Sinica. 2024, 79(7): 1631-1646. https://doi.org/10.11821/dlxb202407001

    Geographic environment has exerted profound effect on the origin and evolution of world civilizations. Chinese civilization budded and evolved on a vast and varied territory between Yellow and Yangtze rivers, and has been thus deeply affected by the local geographic conditions. But it has been hardly seen to explore the origin of Chinese civilization from the perspective of geography. On the basis of integrated scientific investigation in China's north-south transitional zone, geographic analysis of Neolithic culture distribution and interpretation of pre-Qin and Qin-Han ancient literature, the conclusions can be drawn as follows: (1) The early agriculture pattern of "Rice in the south and millet in the north" and the ancient astronomy formed before about 8000 years were the background for Chinese civilization. The geographic distribution of Neolithic Dadiwan, Yangshao, Majiayao and Longshan culture sites showed that the earliest civilization elements appeared in the upper reaches of West-Hanshui and Weihe rivers, with a spatial trend of spreading toward east. (2) The West Qinling Mts. region, located between the Tibetan Plateau and the Jialing River, especially its inner Chenghui and Xili basins, being characterized by superior natural conditions and resources, is closely related to the three major mysteries concerning the origin of Chinese civilization, i.e., the main areas of the ancient Di and Qiang ethnic groups, the location of ancient Kunlun Mts., and the site of Dayu water control. (3) The Qin ethnic group stepped onto the stage of history by assisting Dayu in water control, and in their history of multiple ups and downs, built the grand water control projects in ancient China, such as the Dujiangyan Irrigation Project, Zhengguo Canal, Lingqu Canal, etc., and pioneered the time of "Books with the same text" and "County system", forming the main line of the origin and early evolution of Chinese civilization. (4) The West Qinling areas are still basically a "blind zone" in archaeological and historical research. It is highly recommended to conduct systematic and in-depth archaeological and historical research in this region so as to realize the breakthrough in the exploration of the origin of Chinese civilization as soon as possible.

  • Population and Urban Studies
    DING Jinhong, CHANG Liang, CHEN Yihao, HUANG Xiaoli
    Acta Geographica Sinica. 2024, 79(8): 1883-1897. https://doi.org/10.11821/dlxb202408001

    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.

  • LUCC and Surface Process
    LIU Shiqi, WANG Ping, YU Jingjie, CAI Hongyan, YANG Linsheng, MU Cuicui, LIU Changming
    Acta Geographica Sinica. 2024, 79(7): 1751-1767. https://doi.org/10.11821/dlxb202407008

    Thermokarst lakes, as prominent thermokarst landscapes in permafrost regions, significantly influence ecological vegetation, hydrological processes, and carbon cycling in the Arctic. However, the current understanding of the distribution characteristics and change mechanisms of Arctic thermokarst lakes remains limited. To address this gap, this study employs meta-analysis and mathematical statistical methods to investigate the distribution patterns and dynamics of thermokarst lakes. The results reveal a pronounced spatio-temporal heterogeneity in the distribution and changes of Arctic thermokarst lakes. These variations are closely associated with permafrost conditions, lithology, soil types, subterranean ice content, and soil temperatures. Most Arctic thermokarst lakes are located in continuous permafrost area, where subterranean ice content exceeds 10%, average soil temperatures are above -4°C, and there are specific vertical soil temperature gradients. The change trends of thermokarst lakes differ under various environmental conditions. Generally, the development of thermokarst lakes follows three stages: initial formation, mid-term expansion, and late-stage contraction, all influenced by hydrological and thermohydrological balances. As critical indicators of permafrost degradation and climatic environmental changes, thermokarst lakes profoundly impact carbon cycling, hydrological processes, and ecological environmental changes within the Arctic ecosystem.

  • Spatial and Industrial Development
    LI Wei, YANG Wen, WANG Lucang, QI Jianwu, WANG Zongxiang
    Acta Geographica Sinica. 2024, 79(6): 1449-1463. https://doi.org/10.11821/dlxb202406006

    Identity and territorial stigmatizations have been studied extensively over a long period of time. However, the interaction between the two has been relatively underexplored. Aimed at retrospection and clarification of the connotations of stigmatization, this study attempts to explore the relationship between pers on-place stigmatization from a geographic perspective. This paper proposes the concept of spatial stigmatization and systematically interprets its geographic process and formation mechanism. The paper puts forward the following arguments. First, spatial stigmatization involves stigmatizers who devalue a place's perceived value and identity construction in a specific historical environment and at a particular cognitive level through incomplete, inaccurate, and non-objective perception of space and its dependent people and objects, resulting in symbolic stigmatization of the place. Second, spatial stigmatization entails imagery construction, separation of the subject, and group interaction in the context of heterogeneous geo-spatial pattern and spatial positioning and symbolization. This forms local or heterogeneous types of direct and indirect stigmatization in different directions and at varying distances on various scales. Third, spatial inequality, exploitation and the struggle for rights, fear and avoidance, and topophilia and social order, are the bases of spatial stigmatization. Additionally, the spatial concentration and internalization of stigmatization is facilitated by complex interactions between people and places through perception, identification, positioning, and marking. This creates a spatial stigmatization mechanism that generates, disseminates, reacts, and reproduces in a continuous cycle. In the face of widespread spatial stigmatization, the key to eliminating its adverse effects lies in rebuilding a place through a new narrative system, correctly understanding the relationship between people and the Earth, and ultimately realizing "de-stigmatization space" in the context of the universal value of the human destiny community.

  • Urban and Rural Development and Population Mobility
    WU Kang, ZHANG Jing, LI Dong
    Acta Geographica Sinica. 2024, 79(6): 1371-1390. https://doi.org/10.11821/dlxb202406002

    Research on urban health constitutes an important issue in the field of health geography and also a strong propeller of the Healthy China Initiative. As the main form that realizes new-type urbanization, urban agglomerations should become the primal sites for the construction of a "Healthy China". The evaluation of healthy cities' development in urban agglomerations has both theoretical and practical values. Based on the concept of urban health and its evaluation models, this paper developed an evaluation framework for healthy cities that involved multiple data sources. With 19 urban agglomerations in China as the research subjects, we used CRITIC weighting and geographical detectors to examine the spatial and temporal development patterns of healthy cities and their influencing factors in 2010 and 2020. The results were fourfold. Firstly, the urban health level of China significantly increased from 2010 to 2020, and the comprehensive health index developed towards a positive skewed distribution, along with a shift from "low in the hinterland - high in the coastal areas" to a "multipolar" pattern led by the coastal and southwest urban agglomerations. Secondly, among various dimensions of urban health, the healthy environment index became improved with narrowed regional differences; while the health services index was still polarized; health collaboration was upgraded with a strengthened intercity health networks; the healthy population index slightly declined and converged to the middle. Thirdly, urban health in China has initially demonstrated the characteristics of a H-H pattern in the Yangtze River Delta and Chengdu-Chongqing regions, as well as L-L clusters in the northern urban agglomerations, the narrowed regional differences, and increasing coordination within each urban agglomeration. Fourthly, the geographical detector found that economy, urbanization and the human capital were significant external factors that affected urban health development. The explanatory power of technological innovation and openness to the outside world were also increasing. The development of healthy cities is yet to be transformed into regional health integration.

  • Population and Urban Studies
    SUN Pingjun, ZHANG Keqiu, CAO Naigang, LIU Ju
    Acta Geographica Sinica. 2024, 79(8): 1918-1939. https://doi.org/10.11821/dlxb202408003

    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.

  • Population and Urban Studies
    DING Liang, HUANG Ziqian, XIAO Chaowei, ZHANG Junshen, ZHAO Hua
    Acta Geographica Sinica. 2024, 79(8): 1898-1917. https://doi.org/10.11821/dlxb202408002

    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.

  • Spatial and Industrial Development
    WANG Hua, ZHOU Guohua, ZHAO Wanmin, WU Guohua
    Acta Geographica Sinica. 2024, 79(6): 1478-1502. https://doi.org/10.11821/dlxb202406008

    In the course of urbanization in mountainous and hilly regions, the rapid and disorderly expansion of urban areas has led to environmental degradation of natural landscapes, the gradual erosion of cultural heritage inherent to landscapes, and an intensification of the conflict between human activities and environmental preservation. This dilemma has emerged as a prominent challenge confronting the sustainable development of cities. The integrated advancement of mountain management, water governance, and urban planning emerges not only as a pragmatic imperative for new urbanization and the realization of a visually appealing China, but also as a pivotal pillar supporting urban spatial restructuring and the pursuit of green, low-carbon transformations. This study advocates for a comprehensive exploration of the reciprocal influences and interactions between urban spatial expansion and natural landscapes, necessitating the adoption of an integrated research pattern. This pattern systematically scrutinizes the organizational dynamics and mechanisms of interaction among urban physical spatial configurations, natural ecological networks, and the structure of landscaping and cultural spaces. The spatial pattern termed "mountain-water-city" encapsulates the symbiotic relationships forged through the interplay and adaptation between urban artificial environments and natural landscape environment, with an emphasis on the holistic fusion of urban spaces, natural elements, and cultural components. Building upon this conceptual foundation, the present paper endeavors to elucidate the theoretical contexts and practical imperatives underlying the investigation of the "mountain-water-city" spatial pattern. It delves into the conceptual nuances of this spatial pattern, elucidating its constituent elements, hierarchical scales, and formation mechanisms from a comprehensive perspective integrating spatial, natural, and cultural interactions. Subsequently, it examines the analytical framework and future prospects for research on the "mountain-water-city" spatial pattern, which should center on analyzing its spatiotemporal processes, identifying key controlling factors, and discerning its evolutionary patterns. Furthermore, it should elucidate the driving mechanisms, organizational models, and holistic impacts shaping the formation and evolution of the "mountain-water-city" spatial pattern, as well as explore governance strategies and regulatory pathways conducive to fostering the symbiotic development of this spatial pattern.

  • Theory and Methodology Exploration
    ZHAO Wenwu, YIN Caichun, ZHANG Junze, FU Bojie
    Acta Geographica Sinica. 2024, 79(11): 2699-2720. https://doi.org/10.11821/dlxb202411001

    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.

  • Land Use and Ecosystem
    LI Shuang, ZHANG Xiaohong
    Acta Geographica Sinica. 2024, 79(5): 1286-1302. https://doi.org/10.11821/dlxb202405012

    Shanghai is one of the most significantly urbanized cities in modern China, and its urban spatial pattern and urban area have changed dramatically since its opening up (1843-2020). Reconstructing and analyzing the expansion process of Shanghai has great importance toward attaining a deeper understanding of China's urbanization. This study collected multi-source and multi-precision urban spatial data such as old urban maps, topographic maps of the Republic of China (1912-1949), declassified images from the U.S. military (KeyHole), and remote sensing data (Landsat), and reconstructed a long time series of urban built-up areas, and finally examined the evolution process and driving forces of the spatial structure of Shanghai. The results show that: (1) Since 1843, the area of urban built-up areas increased tremendously, with a total expansion of about 1453 times, and the expansion rate and expansion intensity also changed drastically. (2) The overall change trend of compactness is decreasing, and the fractal dimension shows a certain cycle. (3) The center of gravity of the built-up area in different periods showed a trend of developing first to the north and then to the south, and the most important direction of expansion was southwest and west by south. (4) The urban change was complicated by multiple driving factors: the natural location established the prerequisite for the development of Shanghai as a port city; as the most fundamental driving force, social change and policy determined the main direction of urban development at different stages; the spatial agglomeration of industry and trade is the direct cause of the formation and expansion of cities; population migration also injected new impetus into the urbanization; transportation, as an urban infrastructure, has been used to strengthen the connection between the city's external and internal regions. This study clarifies the processes and mechanisms of urban expansion in Shanghai and provides historical knowledge and scientific support for a deeper understanding of urban change and the evolution of the human-land relationship. Moreover, the ways in which a set of general data with a wide coverage and high resolution can be used for the study of the spatial and temporal processes of urban expansion on a centennial scale are discussed, which is quite instructive for understanding the pre-remote sensing era and developing longer time series.

  • Geopolitical Relations and World Geography
    XIA Qifan, DU Debin
    Acta Geographica Sinica. 2024, 79(6): 1612-1628. https://doi.org/10.11821/dlxb202406015

    Strategic critical minerals are essential materials that will dominate the energy transition and technological revolution. In the context of global climate change and industrial transformation, the geopolitical phenomenon of major powers competing for critical minerals has rapidly emerged, yet relevant research remains relatively limited. Therefore, this paper aims to summarize the geopolitical research on critical minerals, elucidate the geopolitical logic behind them, and reveal the geopolitical patterns of critical minerals. Geopolitical research on critical minerals continues to be dominated by the West, while the domestic research is still in its initial stage. The geopolitical issues on critical minerals are driven by the demand consciousness raised by climate change and energy transition, the competition consciousness intensified by technological revolution and military-industrial innovation, as well as the crisis consciousness generated by the high concentration of supply chain. Technological complexity and application frontiers have determined that industrial and technological competition will lead the geopolitical future of strategic critical minerals, and thus the major powers have always been the absolute protagonists on the world stage. The United States holds the center stage in global competition, and despite its resource endowment, China faces significant security challenges. China should be acutely aware of this reality and formulate appropriate plans. The focus should be on strengthening geopolitical research on critical minerals based on theoretical foundations, enhancing geo-economic deployment of critical minerals with a focus on key areas, and constructing geo-security strategy for critical minerals guided by national demand.

  • Surface Process and Environmental Change
    YAN Yuqiang, LI Xiangying, LIU Sha, YANG Rui, SU Xirui, YI Tong
    Acta Geographica Sinica. 2024, 79(5): 1129-1145. https://doi.org/10.11821/dlxb202405003

    Glacial meltwater is a major carrier of nutrients and bioactive compounds, and meltwater chemistry is an important way to study the glacier drainage system and its dynamic characteristics to gain insights into the biogeochemical cycling process and explore the relationship between deglaciation and climate change. With accelerated melting of glaciers and increases in erosion and weathering, meltwater chemistry has undergone significant changes, which may have significant impacts on downstream water quality, the water environment, and ecosystems. In this study, the contents of inorganic chemical components and their spatial and temporal variations, solute sources and their proportions, and the relationship between chemical weathering and carbon cycling in global glacial meltwater were reviewed. The results indicated that meltwater chemistry is affected by various factors, such as the nature of the bedrock, the drainage system, the physical chemistry, and the topography and geomorphology. To provide references for future research on the relationships among the cryosphere, carbon cycle, and climate change, it is essential to strengthen simultaneous and continuous monitoring of hydrometeorological parameters and inorganic and organic chemical components in meltwater, evaluate the ecological and environmental effects of solutes sourced from glaciers, and examine the relationships among the coupled mechanisms of chemical weathering in glacial regions, solute mobilisation, and atmospheric CO2 balance.

  • Hydrographic Geography and Environmental Research
    WENG Jiaze, YANG Yixin, MU Zhenxia, YANG Long
    Acta Geographica Sinica. 2024, 79(11): 2768-2779. https://doi.org/10.11821/dlxb202411005

    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.

  • Urban and Rural Development and Population Mobility
    LIN Jinping, WU Kangmin, YANG Shan
    Acta Geographica Sinica. 2024, 79(6): 1391-1411. https://doi.org/10.11821/dlxb202406003

    This paper aims to examine the characteristics and patterns of the spatial linkage networks of urban economic efficiency so as to provide new policy insights into the regional integration process. The study builds a theoretical framework to analyze the spatial linkage of urban economic efficiency among cities from the perspective of scaling law. It constructs an analytical paradigm to reflect the network externalities. The Yangtze River Delta Urban Agglomeration (YRDUA) is selected as a case study, and the improved gravity model and social network analysis are applied to measure the urban economic efficiency from 2000 to 2020, analyze the strength of inter-city linkages, and construct a spatial linkage matrix. The results reveal that: (1) the high economic efficiency zone of the YRDUA is gradually shifted from the high-grade cities in the east to the low-grade cities in the northwest; (2) the high-grade cities occupy a central position in the network, forming solid links and "small groups" with the neighboring cities; (3) in the linkage pattern of the urban agglomeration, the Shanghai-Suzhou, Hangzhou-Ningbo, and Hefei clusters show a dual-center, radiation-type and siphon-type coexistence. In contrast, the Nanjing cluster shows a single-center radiation pattern. The linkage paths of the cities in these four clusters are relatively fixed, and the linkage patterns evolve slowly. These findings coincide with the theory of city "quality" in urban geography and the theory of city links in economic geography, and provide empirical support for the integrated and coordinated development of the YRDUA, as well as emphasize the importance of the coordinated development pattern of the "wild goose" echelon structure, which is essential for the understanding of the development of the YRDUA.

  • Theoretical and Methodological Exploration
    LIU Wanzeng, CHEN Jun
    Acta Geographica Sinica. 2024, 79(5): 1099-1114. https://doi.org/10.11821/dlxb202405001

    The empowerment of spatio-temporal information fully releases and amplifies its value as a critical factor of production, meeting the need of the era to support the high-quality development across diverse economic and social sections. Currently, foundational research into the empowerment of spatio-temporal information remains undeveloped, predominantly constrained by the perception that empowerment is synonymous with application. The lack of comprehensive understanding and investigation into its mechanism results in ambiguity in both the connotation and extension of spatio-temporal information, as well as the intrinsic mechanism of its empowerment. Such vagueness restricts the empowerment in a scientific and efficient manner. There is an immediate necessity to delineate its fundamental essence, mechanisms of empowerment, and operational modes clearly. To address the aforementioned challenges, this paper defines the foundational concept, explores the rich connotation, and outlines the essential characteristics of spatio-temporal information. It posits that entropy serves as the physical foundation for the empowerment of spatio-temporal information, with entropy decrease acting as its inherent driving force. The empowerment of spatio-temporal information utilizes spatio-temporal information as the medium, driven by the negative entropy flow, marked by the transformation of inherent uncertainty. This process enhances both the system's structure and performance through the dynamic interplay among humans, machines and the external environment. This paper describes three empowerment modes of spatio-temporal information: taking spatio-temporal information as the in-itself information for direct empowerment, employing it as the being-itself information for indirect empowerment, and converting it into spatio-temporal knowledge for enhanced empowerment. Lastly, this paper investigates the pathways through which the empowerment of spatio-temporal information contributes to the high-quality development of natural resources.

  • Theory & Methodology and Discipline Development
    ZHONG Jingqiu, GAO Mengfan, HAN Zenglin, ZHOU Chenghu, YAN Xiaolu
    Acta Geographica Sinica. 2024, 79(7): 1682-1699. https://doi.org/10.11821/dlxb202407004

    Cultural ecosystem services (CESs), as the non-material benefits and well-being provided by ecosystems to humans, can bridge and interpret the complex relations between nature and human society and can be organised around "spatial needs-spatial planning-spatial production" to achieve sustainable development and human well-being through top-down and bottom-up interventions. Accurately grasping the practical path of CESs involved in the spatial reconstruction of the human-land relationship is not only a scientific problem that needs to be solved to realise the effective enhancement of human well-being but also an important theoretical basis for realising the harmonious coexistence of human beings and nature. For this reason, based on the deconstruction model of "theoretical analysis-associated mechanism-practical application-development path", this study explores the inherent logical system and feasibility of CESs guiding the spatial reconstruction of the human-land relationship and discusses the value assessment-value trade-offs in the process. Based on the evolution of research on CESs in the "flow" era, this study constructs a framework for CESs to guide the spatial reconstruction of the human-land relationship and use it as a theoretical basis for exploring its application in guiding the spatial reconstruction of the ecological-production-living spaces. This framework is then used to develop a program of data collection, methods system, and practical application to realise the transformation of research on CESs from theory to practice and provide new perspectives for the spatial reconstruction of the human-land relationship in the new period.

  • Theoretical and Methodological Exploration
    XIA Jun, ZHANG Shiyan, ZHANG Yongyong, SHE Dunxian, YANG Jun, WU Shengjun
    Acta Geographica Sinica. 2024, 79(9): 2163-2175. https://doi.org/10.11821/dlxb202409001

    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.

  • Geopolitical Relations and World Geography
    NIU Fuchang, GE Yuejing, ZENG Zhuo, DOU Wei, ZHAO Zhengxian, FU Ningning, LI Yanzheng
    Acta Geographica Sinica. 2024, 79(6): 1573-1591. https://doi.org/10.11821/dlxb202406013

    Geopolitics is increasingly a focus in ethnography and social networks research, with an urgent need for China to address international criticism regarding the persistent conflicts of ethnic armed organizations (EAOs) in northern Myanmar. These critiques suggest that EAOs maintain "killed but not extinguished" and conflict persistence, drawing sustenance from a complex cross-border network with China, gaining essential resources like food and shelter. Employing long-term ethnographic tracking and social network analysis, this study examines the intricate relationship between the China-Myanmar cross-border complex social networks and the conflict in northern Myanmar. It starts with the "survival decision-making mechanism," which decomposes the survivability data obtained by EAOs in northern Myanmar into three stages: data acquisition, the extent of complex social network data obtained, and the volume of such data. The survivability data linked to these cross-border networks is empirically tested using the Triple-Hurdle model. The discussion emphasizes ethnography's novel contributions to geopolitical research, showcasing its growing relevance and validity in this domain. The findings reveal that: (1) Under the influence of transaction costs or not, the impact of cross-border complex networks on the conflict's sustainability and the EAOs' resource acquisition is marked by uncertainty, negative and weak positive influences, indicating no direct and inevitable link to the conflict's persistence in northern Myanmar. (2) Transaction costs serve as a mediating factor, with their reduction not directly correlated with the data acquired by EAOs. However, the primary role of cross-border networks is to "expand" cross-border complex social networks, increase transaction frequency, and reduce uncertainty, thereby lowering transaction costs. (3) Control variables like education level, age, and livelihood status have varying impacts on data acquisition stages, showing characteristics of coexistence of positive and negative, significant differences in levels, etc. This study's integration of ethnography with complex network analysis provides a comprehensive geopolitical analysis, enriching the ethnographic geopolitical narrative of the continuous conflict in northern Myanmar.

  • Theoretical Exploration
    YANG Yongchun, JIAN Yuting
    Acta Geographica Sinica. 2024, 79(10): 2425-2441. https://doi.org/10.11821/dlxb202410002

    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.

  • Surface Process
    CHEN Jinfeng, TENG Lizhi, LIU Ruiqing, CHENG Heqin, REN Zhongda, JIN Yang, ZHANG Hong, JIA Zhengyang, ZHOU Quanping, XING Haibin
    Acta Geographica Sinica. 2024, 79(9): 2246-2260. https://doi.org/10.11821/dlxb202409006

    In recent years, the tidal limit of the lower reaches of the Yangtze River has shifted upward, the construction of water-related projects has increased, and the intensity of river bank failure disasters has been on the rise. Previous researchers have found the existence of strong vertical-axial backflow in the bank failure section through field surveys, physical modeling, and numerical simulation, and that there is a strong vertical-axial backflow in the bank failure section; however, the hydrodynamic zone characteristics of the bank-channel interactive zone and the microgeomorphic adaptation mechanism have not been explored. Based on the Doppler acoustic current profiler (ADCP) in the frequent bank failure sections, multibeam system, combined with previous high-resolution underwater topographic data, it is found that the flow velocity and flow direction in the interactive zone of the bank-channel have significant zone characteristics, and according to the backflow strength α, i.e., the longitudinal flow velocity u and its ratio to the transverse flow velocity v, |u/v|, the zone from the channel to the bank is identified into the main stream zone (α<1, u>0), the mixing zone (α≥1), and the near-bank backflow zone (α<1, u<0). The mainstream zone develops large and medium-sized dunes, scour grooves, and scour pits, the mixing zone develops accumulators and small dunes, and the backflow zone develops spines and small dunes; the main stream direct flushing in the mainstream zone and the backflow lateral erosion in the backflow zone are the main driving forces for the development of scouring microgeomorphic type and the development of bank failures, and the high flow velocity gradient in the mixing zone near the main stream zone generates scouring geomorphology, and the remaining part of mixing zone remains a low flow-velocity to make the sediment fall and silt to form the accumulation body. The findings can provide important references for the disaster remediation and near-shore engineering design and monitoring.

  • Urban-Rural and Regional Development
    SHI Minjun, SUN Yiwen
    Acta Geographica Sinica. 2024, 79(10): 2495-2510. https://doi.org/10.11821/dlxb202410006

    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.

  • Geopolitical Relations and Human Settlements Environment
    TIAN Shenzhen, ZHANG Yue, LI Xueming, YANG Jun, LI Hang, CONG Xueping, SUN Huiying
    Acta Geographica Sinica. 2024, 79(8): 2115-2140. https://doi.org/10.11821/dlxb202408013

    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.

  • Regional Development
    WANG Fang, HOU Jingyi, NIU Fangqu
    Acta Geographica Sinica. 2024, 79(8): 2083-2096. https://doi.org/10.11821/dlxb202408011

    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.

  • Surface Process and Environmental Change
    HUANG Lei
    Acta Geographica Sinica. 2024, 79(5): 1192-1210. https://doi.org/10.11821/dlxb202405007

    As a crucial ecological service provider and a key regional growth pole, the upper reaches of the Yangtze River faces significant environmental pressure due to enormous resource consumption during rapid economic development, posing a threat to the stability of its ecosystem. Based on the panel data from 47 prefecture-level and above cities in the upper reaches of the Yangtze River from 1998 to 2021, this paper comprehensively used Dagum Gini Coefficient, kernel density estimation, Markov Chain, spatial convergence model and other methods to deeply analyze the spatiotemporal pattern of environmental pressure. The results are as follows: (1) During the sample period, the overall pressure showed a slight upward trend in an inverted "V"-shaped pattern. The environmental cost of economic growth was high in the early stages, but the environmental risk was effectively controlled in the later stages. (2) The pressure demonstrated a pattern of "high in the east and low in the west" and "high-pressure areas contracted and low-pressure areas expanded". The three urbanized areas in the east, especially Chengdu-Chongqing region, were the pressure centers. However, due to the implementation of the environmental protection policies in the Yangtze River Basin, the scope of high-pressure cities significantly decreased. (3) The overall difference of the pressure exhibited a gently periodic fluctuating trend, with regional difference, net inter-regional difference, and hypervariable density tending towards a state of equilibrium. There were a few stable high-pressure cities in Yunnan-Guizhou region. (4) The evolution of the pressure shifted from a "multi-polar differentiation" trend to a "low-pressure concentration" trend. Initially, there were significant gradients in environmental pressure among cities, but in the later stages, most cities tended to converge towards lower pressure levels. (5) The relative situation of the pressure showed strong stability, but gradually decayed over time, and there existed spatial infiltration effect on the pressure changes. (6) The convergence trend of the pressure was robust, and the spatial proximity accelerated the convergence of environmental pressure. The tightening of environmental policies in the later stages further accelerated the convergence process. This study could provide decision-making support for strengthening ecological security barrier in the study area.

  • LUCC and Surface Process
    LI Shuangshuang, DUAN Shengyong, HU Jialan, YAN Junping
    Acta Geographica Sinica. 2024, 79(7): 1768-1786. https://doi.org/10.11821/dlxb202407009

    Quantifying the contributions of climate change and human activities to changes in vegetation is important in terms of regional ecological protection and future research on the Loess Plateau. However, in the case of areas with naturally regenerated vegetation, where there are no clearly visible indications of human activities and ecological processes are not significantly disturbed, not all relevant forms of human activity can be remotely detected. Therefore, modelling the intensity of human modification of natural ecosystems could provide a pathway for a better understanding of the questions concerning where and how much vegetation change occurs in areas with evidence of human activities or land-use change. In this study, we utilized the Normalized Difference Vegetation Index (NDVI) between 2000 and 2022 and land-use datasets (a spatial resolution of 30 m) collected in 2000, 2010, and 2020 to distinguish areas with strong and weak anthropogenic interference on the Loess Plateau. In those areas with clearly visible human activity, we explored the relative contributions of climate change and human activity to vegetation dynamics. Taking the lagged duration variation between climate factors and vegetation growth into consideration, climatic factors influencing vegetation decadal dynamics were identified in the southern part of the Loess Plateau. The results are as follows: (1) With the implementation of the Three-North Shelter Forest Program, Grain-to-Green Program, and other ecological projects, the rate of vegetation restoration on the Loess Plateau slowed by 3.4%/10a during the period 2012-2022; however, the overall trend was an increase in vegetation. (2) In sensitive areas of vegetation restoration in the Loess Plateau, human activities with a relative contribution exceeding 65% were the dominant factors of vegetation variability in the areas with both intensive and weak human interference, which is approximately 2.0-fold higher than the contribution of climate change. (3) The interdecadal anomalies of precipitation in June were effective indicators of opposite west-east vegetation anomalies in the southern part of the Loess Plateau. Specifically, when precipitation increased by 10 mm in June, this southeastern part witnessed a decrease of 1.4% in NDVI in contrast with a 1.7% increase in the southwestern part. By coupling temporal and spatial information we have clarified the spatial distribution of trends and decadal variations in NDVI and its influencing factors. These observations from the Loess Plateau provide useful insights to help understand the relationship between vegetation change, climate change, and human activities on vegetation restoration globally or in other regions of China.

  • Land Use and Ecosystem
    WANG Xu, FU Xuecheng, XU Wentian, YAO Lei
    Acta Geographica Sinica. 2024, 79(5): 1318-1336. https://doi.org/10.11821/dlxb202405014

    Deepening the understanding of thermal comfort conditions of urban and rural residents is important for improving the outdoor thermal environment. Based on ERA5-Land reanalysis data, this study quantifies the thermal comfort along the urban-rural gradient (urban core-urban expansion-rural area) in 101 large cities in China during the summers from 2000 to 2020 by taking physiological equivalent temperature (PET) as the evaluation index, and explores the spatiotemporal characteristics of thermal comfort and its drivers along different gradients using the Sen's slope estimation, Mann-Kendall significance test and geodetector model. The results show that: (1) The average PET in the core areas (29.89 ℃) of case cities is slightly higher than that in the expansion areas (29.86 ℃) and much higher than that in the rural areas (28.94 ℃), and the cities with higher PET in each gradient are mainly located in the Beijing-Tianjin-Hebei region and the middle reaches of the Yangtze River. (2) PET shows an increasing trend from 2000 to 2020, with an increasing rate of 0.24℃/10a in the core and expansion areas, and 0.22 ℃/10a in the rural areas. (3) Natural factors dominated by vegetation coverage and socioeconomic factors dominated by population density are key determinants of PET in the core and rural areas, respectively, while the drivers of PET in the expansion areas are unstable, with vegetation and impervious surface coverage playing an increasing role. As PET rises, the population exposed to uncomfortable environments increases, and this state of affairs poses new challenges for addressing thermal environmental issues. In the future, more studies on the thermal environment in urban and rural areas need to be conducted to provide a more comprehensive reference for the development of thermal adaptation strategies.

  • Spatial and Industrial Development
    ZHANG Lei, SUN Wei, SONG Yan
    Acta Geographica Sinica. 2024, 79(6): 1540-1555. https://doi.org/10.11821/dlxb202406011

    Airport cluster has become an emerging field of research in air transport geography. Using the social network analysis method, we analyzed the spatiotemporal evolution of the world-class airport cluster's aviation network in the Northeast Corridor of the United States from 1993 to 2018. This paper found that in this region the aviation network has undergone the transformation from the formative period to the mature period. The results are as follows: (1) The "core-edge" structural characteristics tended to be more significant, more flights concentrated in the core airports while the flights between the edge airports and core airports decreased. The core airports grew rapidly, and connectivity among core airports enhanced. Meanwhile the domestic and international transit function of some core hubs was strengthened. (2) The structural characteristic of the hub and spoke was gradually obvious, while the number of hub airports connected by spoke airports reduced. This means that the spoke airports focused the flights to the hub airports in the nearby multi-airport system. (3) The small-world characteristic and node hetero compatibility of the aviation network became obvious, nevertheless, the reduction of hub airports connected by the spoke airports resulted in the decrease of cluster coefficient. The formation of the hub-and-spoke structure weakened the small-world characteristic of the aviation network. Based on the empirical analysis, this paper constructed an aviation network evolution model of airport cluster in small and medium scales, which can provide an empirical basis for the development of aviation network evolution theory, as well as theoretical and empirical reference for the planning and construction of world-class airport clusters in China.

  • "Pole-Axis System" Theory: Review and Practice
    LU Dadao
    Acta Geographica Sinica. 2024, 79(12): 2951-2960. https://doi.org/10.11821/dlxb202412001

    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.