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.

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.

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.

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.

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.

High-quality development of the marine economy is a key task for accelerating the construction of a maritime power, so as to realize Chinese-style modernization. This paper defines the scientific connotation of marine economy and its high-quality development. Based on the three major systems of marine economy and the five new development concepts, this paper synthesizes the high-quality development index of marine economy by means of vertical and horizontal separation grade method and fixed-base efficiency coefficient method. Then, with the help of the method of Dagum Gini coefficient, Markov matrix, standard deviation ellipse and geographic detector, spatio-temporal evolution and driving factors of high-quality development in coastal areas are systematically discussed. The results show that: (1) The continuous improvement of the comprehensive level of high-quality marine economic development is due to the collaborative optimization of marine economic, social and environmental systems. Guangdong, Shandong, Shanghai, Jiangsu and Zhejiang are key regions leading the improvement of marine economic quality and efficiency. (2) The quality of marine economic development has obvious spatial and temporal differences. To be specific, there is a large gap within the southern blue economic circle, and the gap between the northern and eastern blue economic circles is also the most prominent. (3) The high-quality development of marine economy is moving forward in twists and turns. In terms of time, most provinces have the power to advance to a higher level, but the difficulty of transition is gradually increasing; In terms of space, the center of gravity of the marine economy's geographical pattern is always located in the Yangtze River Delta, forming a steady-state spatial structure of "one core and two wings". (4) The optimization of the quality of marine economy is the result of the joint action of the new development concept. After the introduction of the strategy of maritime power, innovation empowerment has replaced opening-up as the first driving force. In order to steadily promote the high-quality development of the marine economy at a higher level, it is necessary to implement the new development concept, which include give full play to the leading role of the blue economic zone, enhance the core competitiveness of the marine industry, build a free trade port with high standards, promote the cause of revitalizing the sea through science and education to cultivate new quality productive forces, deepen the construction of marine ecological civilization as well as clarify the key tasks of coastal areas. In this way, the sound operation of the marine economic, social and environmental systems tend to be promoted, completing the glorious mission of transforming to a maritime power.

Rural development in the new era has ushered in material development opportunities but it is still faced with significant problems of imbalance and inadequacy. Rural social innovation is not only an important endogenous driving force to promote socioeconomic development and reform, but also a key force to break the dual "exogenous-endogenous" structure in rural areas, realize their neo-endogenous development, and promote the full implementation of the rural revitalization strategy to build a livable, viable, and beautiful countryside. This study interprets the conceptual characteristics of social innovation and rural social innovation in the theoretical perspective, sorts out the practical evolution of rural social innovation at home and abroad, explains the internal logic of rural social innovation and rural revitalization in the new era, summarizes the pathway for the realization of rural social innovation to promote rural revitalization, and looks ahead to the future key research areas of rural social innovation. The results show that the essence of rural social innovation lies in enhancing the active capabilities of rural society to achieve sustainable social benefits and promote rural sustainable development. From the perspective of social innovation theory, China's rural development has gone through an initial trial stage, a tortuous exploratory stage, a formal practice stage, and an innovative development stage. Rural social innovation plays a positive role in promoting rural revitalization and neo-endogenous development through innovation initiatives, processes, representation, and goals. In addition, rural revitalization can also react to and strengthen rural social innovation. According to the strategic and practical needs of rural revitalization, one method for promoting rural revitalization through rural social innovation is to reconstruct the relationships among the government, markets, and society. Future research into rural social innovation in the new era should be focused on examining its logical evolution and theoretical exploration, identifying its key elements and invisible thresholds, summarizing its network evolution and driving mechanism, and realizing its dynamic tracking and effect evaluations to provide theoretical guidance and a practical reference for the neo-endogenous development of rural revitalization in China.

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.

Streamflow from the Lena River is one of the major sources of freshwater in the Arctic Ocean and has a significant impact on the Arctic atmosphere, sea ice thermal processes and ocean thermohaline circulation. In recent years, streamflow in the Lena River basin is changing significantly with intensified global warming. In order to investigate the response of streamflow to climate change in the Lena River basin, the study firstly analyzed the trends of precipitation, air temperature and streamflow in the basin from 1975 to 2014 using the M-K trend test. Then, we constructed the abcd-cr hydrological model by considering a coupled snowmelt and permafrost module. Based on the abcd-cr model, we simulated climatic scenarios and quantitatively estimated the relative changes of annual and seasonal streamflow and the elasticities of annual and seasonal streamflow to changes in air temperature and precipitation respected to different climate scenarios. Results showed that: (1) Both the annual and seasonal air temperatures in the Lena River showed increasing trends from 1975 to 2014; The annual, summer, and autumn precipitation presented increasing trends while the spring and winter precipitation showed decreasing trends; The annual, spring, autumn, and winter streamflow had significant increasing trends while the summer streamflow showed a non-significant decreasing trend. (2) The climate scenario simulation results quantified the variations in annual and seasonal streamflow resulting from changes in precipitation and air temperature. (3) The results of sensitivity analysis showed that annual streamflow increases with the increase of precipitation and decreases with the increase of air temperature; The impact of precipitation change on seasonal streamflow is similar to that of annual streamflow change. However, the impacts of air temperature varied in different seasons. Specifically, the relative change of summer streamflow is the largest, while that of winter streamflow is the smallest. The impact of air temperature on seasonal streamflow is more complex than that of annual streamflow due to the interactions between seasonal evaporation and freeze-thaw processes. With increasing air temperature, spring streamflow increases, while streamflow in other seasons decreases.

Owing to the long-standing land-sea division, the regional development theory represented by the pole-axis system has conducted insufficient research on the development potential of the land-sea transition zone and even the marine space. In this context, this paper re-explores the marine orientation of the "pole-axis system" theory and investigates the application of the pole-axis system beyond the land-based thinking. Specifically, taking the currently highly-regarded development of the Hainan Free Trade Port (HFTP) as an example, it commences from the general laws of island economies, traces the geographical relationships and development history of Hainan Island, and based on the expansion of the "pole-axis system" theory, deliberates on the development direction and ideas of the HFTP. This paper emphasizes that: (1) The spatial metaphor of isolation and connectivity of islands within the context of the pole-axis system are mutually reinforcing and compatible, and the cultivation and development of the pole-axis system of the HFTP need to take into account the synergetic effects of the island's geographical relationships at different spatial scales, namely the global, national, regional, and local levels. (2) The pole-axis system of HFTP highlights the role of "flow" rather than geographical proximity in the growth of islands and island clusters. The focus on island-island relationships needs to shift from centrality to the exploration of node attributes, while the focus on land-island relationships needs to change from hierarchy to functional complementarity. (3) The HFTP needs to establish an economic and industrial composite pole-axis system that integrates land, island, and sea, and deepen the intrinsic driving force for the coordinated development of different geographic units through the bidirectional interaction of "defining development based on the sea" and "leaning on the land towards the sea". This study hopes to contribute to enriching and enhancing the marine orientation of the "pole-axis system" theory and deepening the study of islands, including the HFTP, other island economies, and the entire island.

The optimal allocation and scientific management of rural logistics resources is the key to unblock the domestic transportation cycle, and it is also the focus of the construction of a powerful transportation country and the integration of urban and rural transportation. From two perspectives of driving and walking, this study constructs a research framework for the evaluation of rural logistics terminal distribution with accessibility and equity. This study analyzes the accessibility of 440000 administrative villages in China and their nearest rural logistics terminal facilities. By using the online map tool, this study reveals the spatial distribution pattern and regional differences of rural logistics terminal facilities, and evaluates the spatial equity of rural logistics terminal facilities at the county level with Lorenz curves and Gini coefficients. The results show that: (1) Accessibility of rural logistics terminal facilities presents significant regional difference, and it declines from the coast to the interior, which is consistent with the socio-economic development pattern in China. (2) Accessibility of logistics terminal facilities presents significant urban-rural differences. According to the comparative analysis of travel distance, travel time, and travel modes, the urban-rural differences have been widened on travel time and by walking. (3) Based on the analysis with rural population distribution, the distribution of rural logistics terminal facilities presents the transport-related exclusion. The above findings can provide scientific support for the scientific layout of rural logistics terminal facilities so that we could promote the people-oriented integrated development of urban and rural transportation, and assist rural revitalization, so as to achieve common prosperity.

China is deeply interwoven with the world, which has an important impact on the economic geographical pattern of Chinese-style modernization. The economic geographical pattern of Chinese-style modernization is mainly configurated by three relations: relations between urban and rural areas, relations between the eastern and western regions, and relations between China and foreign countries. It is the foundation of the new journey of comprehensively building a modern socialist country. Using strategic-relational approach, this paper analyzes the characteristics of pattern evolution dialectically from the perspective of political party discourse and multi-scale spatial characteristics. After 1840, the capitalist world system disintegrated China's unified pattern, and the regional imbalance and rural-urban gap became prominent in China. At the beginning of the 20th century, the imbalance and gaps intensified in China amid the world's multipolar conflicts. The Communist Party of China created the path of the rural areas to encircle the cities and won the victory of the Chinese revolution, which also changed the world pattern. After 1949, under the Cold War, China began to embark on the path of independently building socialism with Chinese characteristics. The relations between urban and rural areas, between eastern and western regions, between China and foreign countries are shifting to balance. Since the reform and opening-up in the late 1970s, globalization and multi-polarization have propelled the transformation of Chinese-style modernization. The imbalance has shifted from worsening to easing, and China has quickly become an important pole in the world. The world is undergoing profound transformation unseen in a century, uneven development between urban and rural areas, between the eastern and western regions, between China and foreign countries is fraught with uncertainties. Coordinating the three relations is the key to the realization of Chinese-style modernization. China-world relations have a U-shaped cycle of 50 years, regional relations play an intermediary role, and rural-urban relations are the easiest to change. It is necessary to strengthen the research of the economic geographical pattern of modernization, and integrate the three relations into a new development pattern. The H-shaped pattern should integrate spatial development strategies and reshape an open oriented, inside-out pattern through institutional innovation and the empowerment of talent resources.

Based on the data from childcare institutions released by the National Health Commission in June 2024, this study examines the spatial differentiation of childcare institutions across China using four provincial-level cities and 332 prefecture-level regions. The research employs ArcGIS spatial analysis methods and Geographically Weighted Regression (GWR) to uncover the influencing factors behind this spatial variation. Key findings include: (1) Childcare institutions in China predominantly exhibit a clustered distribution, characterized by a greater concentration in the east and sparser distribution in the west. This pattern manifests as "large clusters and small dispersions," with significant clusters forming in the Yangtze River Delta, Pearl River Delta, and Bohai Rim, and numerous monocentric clusters centered around provincial capitals and major cities. (2) The number of childcare institutions is positively correlated with the tier of the city. Cities with fewer childcare facilities are numerous and spread out, primarily located in the western and northeastern regions. In contrast, cities with a larger number of institutions are mainly situated in the eastern coastal areas and major central-western cities such as Chengdu, Chongqing, Hefei, and Zhengzhou. (3) The population of children aged 0-4 years plays a decisive role in the spatial distribution of childcare institutions. Per capita disposable income of urban residents, the labor participation rate, and average household size serve as auxiliary factors influencing this spatial variation. While the average household size generally has a negative influence, other factors positively affect the distribution. As city tiers decrease, the impact of these auxiliary factors lessens, with minimal influence on fifth-tier cities. In conclusion, the study offers targeted recommendations for the development of China's childcare services industry.

As the economic polarization has become increasingly prominent of China, underdeveloped regions urgently need radiation and driving forces. Simultaneously, with the notable trends of population return and decentralization, initial conditions have emerged for developing new growth points. China's territorial spatial governance faces new missions, necessitating the exploration of the contemporary value of the "pole-axis system" theory to guide the practice of coordinated regional development. Based on the essence of the "pole-axis system" theory, the central place theory, and the central flow theory, this paper proposes a polycentric and coordinated regional development model of large countries. Drawing upon the empirically verified effective radiation radius of first-tier central cities, this paper envisions establishing new first-tier central cities in the northwest and northeast regions, in addition to the existing four first-tier central cities of Beijing, Shanghai, Hong Kong (Shenzhen), and Chongqing. This endeavor aims to establish a multi-tiered system of central cities that relies on metropolitan areas, urban agglomerations, and urban networks to foster specialized division of labor and collaboration among regions, ultimately guiding balanced national development. As a novel application and extension of the "pole-axis system" theory, the polycentric coordinated development of large countries contributes to achieving the diverse goals of "efficiency-equity-security" in the territorial spatial system. Regarding the implementation path, territorial spatial planning should serve as the guiding force, with market mechanisms as the foundation, and the active intervention of a promising government as the support. This will reverse the imbalanced regional development patterns in China, realize regional coordinated development, and provide spatial support for enhancing China's overall competitiveness.

Tropical cyclone activity has undergone significant changes under the impact of the global warming since the 20th century. However, the characteristic and trend changes of landing tropical cyclones over China still need to be further clarified. We conducted an analysis of the spatiotemporal characteristics and trends of landing tropical cyclones over China from 1949 to 2022 using the dataset of the best tracks of tropical cyclones from the China Meteorological Administration. Additionally, we explored the influences of El Niño-Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO) on landing tropical cyclone activities. The results indicate that: (1) The annual average number of landing tropical cyclones over China is approximately 8.85, showing a significant decreasing trend, and the decreasing range becomes larger with lower latitude overall. However, both the proportion of landing tropical cyclones to the total number and the percentage of higher intensity tropical cyclones increase. The landing tropical cyclones from July to September account for 76.3% of the total, in which August experiences the most. (2) The landing positions of tropical cyclones in China are mainly concentrated between 18°N and 26°N, accounting for approximately 88.2% of the total, and the landing frequency shows a sharp decline in the regions north of 30°N. The central landing position of tropical cyclones has shifted significantly northwestward, moving closer to China. Compared to 1949-1969, the central generating position from 2010 to 2022 shifted 4.5 degrees westward and 2.0 degrees northward. (3) There is a correlation between ENSO and the frequency variation of generating tropical cyclones in the Northwest Pacific and landing over China. El Niño promotes the formation of strong tropical cyclones and leads to a more southeastern bias in the generating positions of landing tropical cyclones, while La Niña has an opposite effect. The PDO also affects the tropical cyclones to a certain extent. During the warm phase of PDO, the generating position of tropical cyclones is westward and the number is less than that in the cold phase. This study further clarifies the changing trends and characteristics of the landing tropical cyclones over China since 1949. It also highlights the impacts of ENSO and PDO on tropical cyclone activities. The findings can serve as a scientific basis for conducting simulations and assessments of tropical cyclones and for disaster prevention and mitigation efforts.

Rural living space is the spatial area that accommodates the daily activities of rural residents. With the acceleration of new urbanization and rural modernization, and the comprehensive promotion of livable, business-friendly, and beautiful rural construction, the demand for rural space by diverse subjects such as original villagers, new villagers, and traveling villagers has shifted from "comprehensive spatial functionality" to "high-quality spatial functionality", presenting new theoretical requirements for the understanding of rural living space. To better serve the construction of livable, workable, beautiful and harmonious countryside, this paper proposes the concept of a "rural living space system". It clarifies the conceptual origins of the rural living space system from three perspectives: geographical understanding of space, the theory of "production of space", and the academic thought of "human-land relationship regional system". It deconstructs the connotations and extensions, elements and structures, functions and values, evolution trends, and risk predictions of the rural living space system. It is suggested that the research on the rural living space system should be carried out from four aspects: theoretical analysis, evolutionary drivers, operational mechanisms, and optimization regulation. Research on the rural living space system is an area that rural geography needs to focus on. Future research should concentrate on the relationships between elements, their evolution and drivers, and innovations in operational mechanisms. Empirical analysis of different types of rural areas should be conducted to establish a theoretical foundation for the optimization and reconstruction of the rural living space system in the construction of livable, workable, beautiful and harmonious countryside, providing case references to enhance the governance capacity and modernization level of the rural spatial governance system.

The morphological characteristics of floods are important indicators for flood prevention and control, and have important indicative significance. Traditional hydrological studies mainly focus on the change of characteristics in flood magnitude under the changing environment, and the characteristics and mechanism of changes in flood morphological parameters under the influence of urbanization and climate change remain to be further explored. Taking the highly urbanized river network area of the Taihu plain as a typical example, this paper proposed a process-based method to identify flood events, and revealed the change in flood morphological characteristics and its driving mechanisms between 1971 and 2020. The results show that not only the flood magnitude (peak water level and water level increment) but also the morphological characteristics of flood fluctuation (such as rate of rising limb and recession) have changed significantly in the Taihu plain under the background of changing environment. Impervious area has a non-linear effect on the flood morphological characteristics. In the study area, the stations with significant breakpoint for peak water level occupy 61.5%, and 76.9% stations showed a significant upward trend. 46.2% of the stations have a significant breakpoint for rate of rising limb, and all stations showed an increasing trend, among which, 38.5% of the stations reach the significance level. A total of 53.8% of the stations have significant mutation and significant trends of recession rate, and the recession rate reaches 0.628 mm·d^-1·a^-1 in the whole period in the study area (p<0.05). The antecedent water level conditions and rainfall characteristics are the main driving factors affecting the flood morphological pattern in the river network area of the Taihu plain. The results of this study could deepen the understanding of flood evolution in the Taihu plain region under a changing environment, and provide reference and support for flood disaster prevention and control in similar plain river network areas.

The growth and cultivation of leading scientific talent has become a hot topic for the government and academia. However, previous research has focused on education and management issues in the process of talent growth, while the geographical factors and processes influencing talent growth have been overlooked and neglected. Based on the education and work resumes of Nobel laureates in science, this paper systematically deconstructs the geographical pathways, regional functions, and influencing factors involved in the growth of leading scientists from 1901 to 2022. The main conclusions can be drawn as follows: (1) The geographical pathways of the growth of leading scientists has a significant institutional community effect, and achieving scientific breakthroughs is highly dependent on a few research institutions. (2) In the education stage, the educational centers where leading scientists grow up exhibit a significant phenomenon of succession, showing a wide range of sources and the highly degree of aggregation of inflows. And the United States, Germany and the United Kingdom account for 78.3% of the volume of leading scientists mobility in the education stage. (3) In the work stage, the geographical pathways of the growth of leading scientists has further narrowed, and there is a clear geographical transfer in the scientific centers where leading scientists work. The United States has become the largest "magnet country", accounting for 53.7% of the volume of leading scientists mobility in this stage. (4) During the growth process of leading scientists, regional functions are divided into six types: birth, education, promotion, birth and education, education and promotion, and omnipotent. After World War II, only the United States has developed into omnipotent type. (5) The influence mechanism of the mobility of leading scientists has its generality and particularity. Language has been widely proven to play an important role in the cross-border flow of the general population, but its impact on the migration of leading scientists is not significant. The proximity of social systems, political environment, and higher education are important factors for leading scientists to consider in their migration. However, the scientific development level of destinations does not significantly affect the mobility of leading scientists in turbulent times.

Projecting changes in flow regime under climate change and reservoir operations is crucial for safeguarding water security, preserving biodiversity and restoring aquatic ecosystems of a basin. Leveraging bias-corrected climate model data, this study utilized the Soil and Water Assessment Tool (SWAT) with an improved reservoir module and Indicators of Hydrologic Alteration to project the impacts of climate change and reservoir operations on the flow regime of the Yangtze River basin in the 21st century. The results showed that: (1) The improved SWAT model outperformed the original version, enhancing the simulation accuracy of daily streamflow and hydrological indicators at representative stations. The NSE (Nash-Sutcliffe efficiency coefficient) and KGE (Kling-Gupta efficiency coefficient) of simulation and observation of daily streamflow increased by 0.01-0.26 and 0.01-0.08, respectively. (2) Climate change is projected to increase streamflow, in which the streamflow increases significantly from January to April (the maximum increase is 17%). Meanwhile, climate change increases the variability of pre-flood streamflow (the maximum increase is 18%), the frequency of extremely high pulse, the duration of extremely high pulse and the rise rate of flow. (3) Reservoir operations effectively replenish dry-season flows (the maximum increase is 67%), reduce the frequency of extremely high pulse (the maximum decrease is 16%), and shorten the duration of both extremely high pulse (by -10% to -4%) and extremely low pulse (by -51% to -38%). Reservoir operations improve the stability of flow. While upstream reservoir operations can partially counteract climate-induced streamflow changes, their regulatory capacity is constrained by operational rules and total storage capacity. Therefore, adjusting reservoir operation strategies in response to the impacts of climate change on streamflow becomes imperative.

To accurately grasp and effectively coordinate the strategic goals of the great rejuvenation of the Chinese nation and the unprecedented global transformations in a century, while enhancing the country's cultural soft power and the influence of Chinese culture, and promoting the construction of a new form of human civilization, the Chinese nation objectively needs to establish a strategic space that supports the inheritance and innovation of Chinese civilization. This strategic space will serve as a cultural landmark for realizing the great rejuvenation of the Chinese nation through Chinese-style modernization. To achieve this, we develop a construction index system for the strategic space of Chinese civilization inheritance and innovation by repeatedly examining China's regional development and historical and cultural territory. The index system comprehensively incorporates factors such as historical and cultural inheritance, rural revitalization, ethnic diversity, and ecological protection and diversity across five dimensions: history, geography, culture, society, and ecology. At the national district/county level, the strategic space for the Chinese civilization inheritance and innovation is divided into infrastructure construction area, key construction area, priority construction area, and core construction area based on the comprehensive evaluation results. The evaluation results reveal that the strategic space has formed a core area around Shaanxi and a southern core area around Guizhou. The construction conception of the strategic space for the Chinese civilization inheritance and innovation and its division provides strategic support for advancing the great rejuvenation of the Chinese nation and facilitating Chinese-style modernization. Additionally, it plays a significant role in preserving the Chinese spirit and promoting rural revitalization as well as coordinated urban-rural development.

In 1984, Professor Lu Dadao first proposed the "pole-axis system" theory and the "T-shaped" spatial structure of China's territorial development and economic layout at the National Economic Geography and Land Planning Symposium. As a model of regional "optimal structure and optimal development", the theory has become one of the milestone research results in the development of human and economic geography in China after continuous improvement and deepening. By reviewing the development process of the "pole-axis system" theory and the "T-shaped" spatial structure, this paper reviews the quantitative characteristics, institutional distribution, published journals, research topics, and hot topic evolution of relevant research literature, and clarifies the characteristics and trends of research in relevant fields in the past 40 years. The findings are as follows: (1) The theory of "pole-axis system" and the "T-shaped" spatial structure have been receiving continuous attention from the academic community, with the number of studies showing a significant correlation with the release of national policies. (2) Key research institutions, such as the Institute of Geographic Sciences and Natural Resources Research at the Chinese Academy of Sciences, Nanjing Normal University, and Central China Normal University, serve as prominent representatives in this field. These institutions collectively cover all regions of China, which may be closely tied to empirical studies of the theories in various areas. (3) The research articles have been published in multidisciplinary journals, exerting a notable influence primarily in the fields of geography and economics. (4) The research themes, research areas and methods of the "pole-axis system" theory have been continuously expanded and enriched in the three stages of development. Then, based on policy analysis and representative evaluation, the research expounds the extensive application and profound influence of the "pole-axis system" theory and the "T-shaped" spatial structure in the fields of territorial spatial planning, regional development strategy and multi-scale regional planning. Furthermore, this paper probes into its application value in the fields of territorial spatial planning with multiple-plan coordination, regional coordinated development, new urbanization and urban-rural integrated development, as well as allocation of new quality productive forces and other major productive forces in the new era.

Traveling has been a constant exploration of new knowledge and experiences in both the journey and the destination throughout the ages. Travelogues, in turn, are direct records of historical travel activities. During the Ming and Qing dynasties, with the improvement of canal transportation and canal systems, a comprehensive water-land transportation network centered around the Grand Canal (Beijing-Hangzhou Canal) and incorporating the north-south postal roads along the canal gradually took shape. This development attracted numerous officials, literati, envoys, and other elite groups, leading to the creation of a substantial number of travelogues and diaries related to the Grand Canal and its surrounding landscapes. Focusing on these travelogues, this study examines the spatiotemporal characteristics and influencing factors of the canal travels of elites in the Ming and Qing dynasties, contributing to a deeper understanding of the operation of transportation systems and the travel patterns of people in traditional societies during historical periods. This article, adopting a perspective of "mobility" and drawing on methods from historical geography, extracts information and expresses spatial characteristics from travelogue texts, revealing the overall spatiotemporal features of canal travels by Ming and Qing elites. Based on this, the study discusses the influences and constraints on individual travel activities. The research findings include: (1) Canal travels during the two dynasties formed concentrated zones, namely the Beijing-Tianjin travel belt in the north and the Huaiyang (Huai'an and Yangzhou)-Jiangnan travel belt in the south, while the central region remained relatively sparse. (2) Under the influence of natural conditions and canal transportation systems, travel activities exhibited a certain temporal rhythm within a year. (3) Factors such as social status, travel destinations, and modes of transportation significantly influenced the behavioral patterns, spatial perception, and emotional experiences of travelers during their journeys. Building on these analyses, this article proposes a mobility analysis framework for historical transportation geography, aiming to provide insights into the application of mobility paradigms in historical periods. This research not only contributes to the understanding of historical travels but also lays the groundwork for further exploration of mobility in historical contexts.

Palaeoflood events are instantaneous responses of hydrological processes to extreme climate. Through field investigation, a loess-paleosol sedimentary profile containing a set of overbank flood deposits (OFD1, OFD2 and OFD3) that recorded the extraordinary palaeoflood events was found on the platform scarp of the Shahe River, a tributary of the Huaihe River. The sediment samples were collected, and the physical and chemical properties and optically stimulated luminescence (OSL) dating were analyzed. The results showed that the end-members analysis of particle size indicated that OFD1, OFD2, and OFD3 were overbank flood deposits affected by hydrodynamic forces. However, the particle size composition of OFD3 and OFD1 primarily consisted of sand (>60%), while the particle size composition of OFD2, S₀, L_t and L₁ was mainly silt (>70%). The magnetic susceptibility values of OFD3 and OFD1 were significantly higher than those of S₀, L_t and L₁, and the contents of Na₂O, K₂O and SiO₂ were higher, while the contents of Al₂O₃ and Fe₂O₃ were lower in OFD3 and OFD1. The particle size composition, magnetic susceptibility value and geochemical element composition of OFD2 were similar to those of S₀, L_t and L₁, but significantly different from those of OFD1 and OFD3. These differences could be attributed to the varying material sources of OFD2, OFD3, and OFD1. OSL dating and a stratigraphic chronological framework of sedimentary profile indicated that the three extraordinary palaeoflood events were recorded during the late Holocene from 1550 to 1400 a BP in the Huaihe River basin. The analysis of high-resolution climate proxy indicators, atmospheric circulation factors, and global mean temperature demonstrated that the extreme flood events that occurred during the late Holocene from 1550 to 1400 a BP were a direct response to the abrupt climate changes, corresponding to the severe climate deterioration period of the Northern and Southern Dynasties in China. These findings are significant in understanding the regional response of hydrological climate change to global change.

Urban agglomerations serve as crucial platforms for constructing substantial domestic circulation and fostering harmonious regional development in China. Given the evolution of the integrated development of urban agglomerations, the characteristics of their internal spatial networks inevitably lead to the carbon peak paths of individual cities being influenced by their proximate counterparts. Consequently, this study focused on the Yangtze River Delta urban agglomeration, which boasts a high degree of integration within China, constructed a spatial weight matrix based on composite geographic and economic dimensions, applied a spatial econometric model to analyze the spatial correlation of carbon emissions in this urban agglomeration, and further applied the spatially embedded Genetic Algorithm-Long Short-Term Memory (GA-LSTM) model to simulate dynamically the peak paths of carbon emissions in this urban agglomeration. The empirical results revealed several important findings: (1) Considering the spatial correlation effects of the urban agglomeration, the carbon peaks of several cities occur sooner than expected, and most cities experience a reduction in their peak level, indicating that the spatial correlation effect can effectively optimize the spatial pattern of carbon emissions. However, the post-peak emission dynamics of these cities are not significantly affected. (2) In the baseline scenarios, with the exception of Suzhou (Jiangsu) and Bozhou, all cities attain their carbon peak by 2030, with most cities in Anhui province maintaining a steady decrease in carbon emissions after 2019, some cities in Jiangsu and Zhejiang provinces experiencing a relatively slow decrease in carbon emissions after reaching the peak, and Shanghai and Nantong showing a rebound trend of slow increase in carbon emissions after reaching their peak at an early stage. (3) Under the green scenarios, the total carbon emissions from the Yangtze River Delta urban agglomeration follow a steady downward trend since 2019, effectively reversing the inertial growth under the baseline scenarios, and the cities within the urban agglomeration show significant improvement in the time to peak, peak level, and post-peak situation, which contributes to a synergistic emission reduction pattern.

Alluvial fans are common fan-shaped depositional landforms that develop at the outlets of mountain rivers or gullies. Mature and stable alluvial fans are important areas for both human habitation and production in mountainous regions, but they also pose potential hazards associated with flash floods and debris flows. Research on alluvial fans enhances our understanding of regional environmental dynamics and geomorphic evolution, as well as contributes to the mitigation of flood and debris-flow hazards. Therefore, it holds significant scientific value and practical importance. Although considerable research has been conducted on alluvial fans, both domestically and internationally, in recent decades, much of it has focused on geomorphology (morphometry), sedimentary history and characteristics, and historical environmental reconstruction (or inversion). Investigations into the mechanisms of fan development and their geomorphic effects remain relatively underexplored. This review systematically summarizes the key advancements in the research on the dynamic processes, mechanisms, and morphodynamics of alluvial fan development. We first provide an overview of current technical approaches applied in the study of alluvial fans, including field investigations and model experiments. Then, we summarize four critical aspects of fan dynamics processes and development mechanisms: primary and secondary processes; mechanisms of flow channel avulsion; interactions between tributary and main rivers; and the impact of alluvial fan development on sediment production, transport, and geomorphic processes. Finally, we discuss several areas that require further attention in future research. Currently, field observations and monitoring of the dynamic processes of alluvial fan development are inadequate. As an essential complement to post-event field surveys and experimental model research, there is an urgent need to enhance field observations in order to expand and deepen our understanding of alluvial fan development mechanisms. This will promote scientific insights into sediment dynamics and geomorphic processes within regional river systems.

The integration of large-scale Low Earth Orbit satellite constellations (hereinafter referred to as "LEO constellations") and artificial intelligence (AI) technology presents a historic opportunity for a paradigm shift in geography research, heralding a new era for geography to evolve from qualitative geography, quantitative geography, and digital geography into the "LEO constellation-AI-driven Geography". Under this framework, future geographic research can rely on the high spatio-temporal resolution monitoring data provided by LEO constellations to accurately capture the high-frequency dynamic changes of geographic elements at multiple scales, particularly at the global scale. By coupling physical models with AI, it becomes feasible to conduct simulation experiments on the complex interactions between natural and human elements, system states, and interface changes. This will facilitate a deeper understanding of core geographic issues such as variable coupling, multi-process cascading effects, and teleconnection mechanisms. To propel "LEO constellation-AI-driven Geography", there is an urgent need to establish a new-generation data acquisition and sharing platform relying on LEO constellation, seamlessly creating a "dynamic map" of global geographic resources and elements. Additionally, a geographic process simulator that couples physical models and AI needs to be developed to intelligently simulate and predict changes and impacts of geographic elements and landscapes.

The valley roads at the northern foothills of the Qinling Mountains deeply cut the main chain of the Qinling Mountains, and are the "natural window" to gain insight into the geology, geomorphology, ecology and hydrological evolution of the Mountains. In this paper, the spatial distribution pattern and development characteristics of the valley roads at the northern foothills of the Qinling Mountains (Shaanxi section) were obtained by using Google Earth remote sensing image data, DEM elevation data and water system vector data, combined with ArcGIS, GlobalMapper multimodal spatial data identification and interpretation. The inheritance relationship between the valley roads at the northern foothills of the Qinling Mountains and the Guanzhong river system was explored. The following understandings were obtained: (1) According to the geomorphological characteristics of the valley roads, the length, pedestrian and water channel, the statistical standard of the valley roads was put forward. Combined with contour terrain and digital elevation model, the zoning interpretation is carried out, and the actual number of valley roads is 206. (2) Based on the visibility of remote sensing interpretation and the endowment water system in the valley roads, 76 representative valley roads were selected for statistical analysis. According to the length (≥15 km, 5-15 km, <5 km), the large, medium and small valley roads were divided. The Xi'an section is the most densely developed mainly for medium valley road (44.74%). (3) The direction of the valley roads is mostly N0°-NE30°, approximately perpendicular to the strike of the Fenwei Fault. The elevation of Yukou is normally distributed, concentrated between 500-800 m. The spacing between the valley roads is the rhythmic distribution of "small valley roads in big valley roads". (4) The elevation of the middle line of the valley roads is mainly distributed at 600-1500 m, the slope is mainly concentrated at 0°-20°, the width of the valley entrances are mainly at 30-90 m, and the shape of the valley entrances are mainly U-shaped, V-shaped and inverted trapezoidal. (5) The valley roads at the northern foothills of the Qinling Mountains and Weihe water system have a close inheritance relationship. Six of the "Eight River Systems in Chang'an" originated from the northern foothills of the Qinling Mountains, characterized by multi-source confluence. The purpose of this study is to provide detailed background data for the study of the most iconic geological and geographical labels in the Qinling Mountains with valley roads.

As an important aspect of the notion that "spatial is special", spatial heterogeneity has been a central topic of geospatial analytics. It is also closely related to the methodological tradition of geography and replicability of geographic research. The emergence of fine-grained big geospatial data and the development of Geospatial Artificial Intelligence (GeoAI) have brought new opportunities and challenges to spatial heterogeneity modeling. Spatial heterogeneity may refer to (1) values of geographic variables; and (2) associations, or the generation process of geographic variables, which correspond to data and process heterogeneity, respectively. Moreover, the specification of spatial heterogeneity may be categorized as continuous and discrete. Based on the dichotomies above, we summarize the main scenarios of spatial heterogeneity modeling and review corresponding methods: (1) homogeneity-based regionalization; (2) local spatial regression; and (3) spatial regime regression. In particular, we discuss approaches to delineate spatial regimes in an endogenous manner. We also review related methodological advances in GeoAI, where the principle of spatial heterogeneity is reflected in the design of neural network models. Finally, we point out several potential directions for future research. As emerging directions in spatial heterogeneity modeling, spatial regime regression and GeoAI methods need more attention from researchers.

The digital economy is a pivotal driver for fostering high-quality economic development in China, which is crucial in attaining carbon peak and neutrality objectives. Given its significance as a core vehicle for national urbanization initiatives, elucidating the influence and spatial implications of the digital economy on carbon emission efficiency at the county and district levels is imperative for China's new urbanization strategy, bolstering ecological civilization and advancing green transformation and development in the contemporary era. Utilizing the entropy weight method and the SBM-DEA model, this study assessed the digital economy's development level and carbon emission efficiency in 19 counties within the Changsha-Zhuzhou-Xiangtan metropolitan area spanning 2011 to 2021. Spatial analysis techniques were employed to delineate the spatiotemporal patterns and clustering characteristics of the digital economy and carbon emission efficiency at the county scale within this metropolitan region. Furthermore, we leveraged the OLS model and the spatial Durbin model to empirically scrutinize the impact and spatial effect of the digital economy on carbon emission efficiency in the study area. The key findings are as follows: (1) There exists a significant disparity in the development of the digital economy and carbon emission efficiency across the Changsha-Zhuzhou-Xiangtan metropolitan area, exhibiting a spatial distribution pattern characterized by "high in the north and low in the south". (2) The digital economy in this metropolitan area consistently exerts a noteworthy stimulatory effect on carbon emission efficiency, and this influence is markedly strengthened upon the inclusion of various control variables. (2) The digital economy in the Changsha-Zhuzhou-Xiangtan metropolitan area exhibits a substantial positive spatial effect on carbon emission efficiency, with a more significant impact on local carbon emission efficiency compared with neighboring counties.