Social-Ecological System (SES) is a collection of social subsystems, ecological subsystems, and the interactions between them. It is a common difficulty of cross-multidisciplinary fields to predict the changes in human-earth systems and support the relevant management decisions through clarifying the interaction between the ecological environment and human society. The framework of ecosystem service provides a new perspective for revealing the transmission and the role of various elements in SES. Taking ecosystem service as an entry point, this study follows the context of "Ecological System Supply-Ecological Coupling Human Intervention-Promoting Social Development". And the research progress and trends of existing coupling simulation methods related to SES are summarized. This article argues that in the conduction research of the ecosystem services cascade, the academic cognition has emphasized the "impact of natural ecosystem to social-economic system" rather than the "interaction and feedback mechanisms for ecosystems and social systems". In terms of research content, scholars have trsnsformed their focus from "changes in ecosystems and environmental effects" to "social-economic system and the effect on different groups". The focus of research has shifted from the theoretical inquiry of the "internal mechanism and power mechanism" to the applied practice of "optimization and regulation strategy" among the coupling systems. Future research of SES should strengthen the simulation of social-ecological coupling with equal emphasis on nature and humanities. It is the focus of breakthroughs to comprehensively understand the internal interactions and feedback of complex systems.

Global climate change caused by human activities results in frequent extreme climate events, and shifts the physiological processes of plants, and the carbon, water cycle and energy balance of terrestrial ecosystems. Vegetation phenology is the most sensitive biological indicator to climate change. In recent years, the responses of vegetation phenology to climate change mainly focus on the mean state of the climate, while the response mechanisms of vegetation phenology to extreme climate are still unclear. In this paper, the response of vegetation spring and autumn phenology to various extreme climatic events and their mechanisms were reviewed. We found that extreme low temperature and extreme precipitation directly delayed the vegetation green-up date and advanced the leaf senescence, while extreme high temperature and extreme drought led to stomatal closure, inhibited photosynthesis and transpiration, and thus advanced leaf senescence at middle and high latitudes of the Northern Hemisphere. Currently, the studies on the response of vegetation phenology to extreme climate events pay less attention to compound extreme climate events, and there are only few studies on the lag effect of vegetation phenology response to extreme climate events and the recovery process of vegetation after the occurrence of extreme events. Under future climate change scenarios, it is necessary to modify the vegetation phenological models by considering the impact of extreme climate events and couple it into the dynamic global vegetation models to improve the simulation accuracy of the carbon cycle in terrestrial ecosystems.

Urban-rural integrated development is an advanced stage in the evolution of the urban-rural relationship, and it is also the basic path and main goal for the implementation of rural revitalization. Scientifically understanding and identifying the integration stage and its current level of urban-rural development in China is the prerequisite basis for promoting urban-rural integrated development and rural revitalization. Based on the concept connotation, this paper constructed a multi-dimensional evaluation system of urban-rural integrated development at the prefecture level. The process status and spatiotemporal divergent characteristics of urban-rural integrated development in 336 prefecture-level regions in China from 2000-2018 were portrayed and revealed. The results show that: (1) The current state of urban-rural integrated development in China is generally at a low-to-middle level, showing a heterogeneous spatiotemporal pattern with apparent gradient divergence. The integrated development level of the Pearl River Delta, Jiangsu and Zhejiang provinces, and the Shandong Peninsula is high, but the regions distributed to the west of the "Hu Line" develops slowly. (2) According to the level and characteristics of integrated development, the 366 prefecture-level regions can be divided into four types: integrated development, tending integration, imbalanced development, and lagging development, with a more active transformation between the latter three types. (3) The development level of urban-rural economic integration is higher than that of demographic and social integration, while the development process of urban-rural spatial and ecological integration shows some natural zonal divergent characteristics. Finally, we identified the problem areas for different types of integrated development and explored the regional promotion path of urban-rural integrated development, which could provide scientific references for the strategies of regional urban-rural development and rural revitalization.

The rise of global neoliberalism and reflexive governance has driven the political flows at the global level. Policy movements thus have shown new dynamics and characteristics. Political science, within the sphere of rational formalism, whose dependence on traditional frameworks, as well as the neglect of geographic mobility in sociology, have limited the explanatory power of existing concepts. The geographical orientation and spatial correlation of policy mobility offer the possibility of a theoretical breakthrough by introducing human geography in the policy research. Based on the literature in geography, this study traces the process of resembling rolling conversation through transdisciplinary research on policy mobility, and further clarifies the conceptual connotations, commitments, and research starting points of policy mobility. As an effective conceptual tool for understanding how policymaking operates, how policy knowledge and models flow, and how these mobilities shape places in the context of neoliberal globalization, policy mobility seeks to clarify the geographic positions, power relations, spatial characteristics, and social and geographical formation processes that are involved in the movements of policies. Policy mobility thus becomes a core field in the social sciences exploring "ideas in motion" and "production of mobilities". In addition, the theoretical orientation and research elements in the study of policy mobility also enhance the explanatory powers of literature from other disciplines to this subject. To a certain extent, this study compensates for the lack of empirical analyses of ideas and knowledge in mobility studies and insufficient research on power theory in human geography. It provides an important research field for applying geography in transdisciplinary research.

Carrying capacity, a concept entrenched in the natural resources and environmental field for nearly two centuries, has continually evolved to address the conflicts and sustainability of the human-nature relationship. This paper introduces an analytical framework for understanding carrying capacity within the context of the human-nature relationship. It systematically reviews the progression of international carrying capacity studies, analyzes global research trends, and compares these with Chinese studies, highlighting key research directions in China. Historically, carrying capacity traces its roots to (neo)Malthusian theories. Its evolution spans four distinct stages: resource carrying capacity (since the 1800s), environmental carrying capacity (since the 1970s), ecosystem carrying capacity (since the 1990s), and natural system carrying capacity (since the 2010s). The concept of carrying capacity varies widely across global disciplines and even within the same discipline, showcasing diverse applications. Carrying capacity has sparked controversy due to its connection to political economy theories and factors such as technological progress, market mechanisms, and spatial and temporal constraints. Therefore, it is imperative to engage in a restrained and explicit discussion and application of carrying capacity. Presently, China's carrying capacity studies align closely with the international community, capitalizing on regional-scale studies employing a holistic and systematic human-nature relationship approach. However, there is an opportunity for enhancement in terms of global-scale perspectives and the integration of natural and social sciences theories and methodologies. This paper proposes fostering innovation and application in carrying capacity research within the Chinese context. This entails integrating various disciplines and theories, exploring scale effects and mechanisms, utilizing model-data fusion and integration, applying case studies in various spatial units and typical zone types, and improving policy systems and institutions.

Deconstructing rural spatial characteristics is the precondition for building rural spatial governance system in the new era, and multi-scale rural spatial characteristics and its governance path would effectively support the modernization of the national governance system. Based on the comprehensive, regional and mobile thinking paradigm of geography, this paper deconstructs the multi-scale rural spatial characteristics, identifies its internal operating logics, summarizes its governance dilemmas, constructs a multi-scale rural spatial governance framework that is based on geographical analysis paradigm, explores feasible governance paths, and constructs a multi-scale rural spatial governance system research plan, namely, "characteristics identification-dilemma analysis-governance framework-governance path". The paper finds that: (1) to analyze the operating logics of the multi-scale rural space through the comprehensive, regional and mobile analytical thinking of geography, it is necessary to understand the mechanism of action of scale synthesis, scale differentiation and scale flow to the multi-scale rural spatial characteristics, highlighting the comprehensive characteristics of rural space, strengthening rural spatial heterogeneity, and integrating rural spatial mobility. (2) The lacking urban-rural spatial overall planning, unsmooth spatial mobile network and not-reflected different types of rural spatial value are the key dilemmas in the rural spatial governance, which need to be addressed. (3) The multi-scale rural spatial governance framework of "comprehensive spatial governance-spatial zoning governance-spatial mobile governance" could effectively solve the problems of urban-rural spatial integration, regional spatial coordination and spatial network blockage. (4) Integrating urban-rural comprehensive governance, innovating regulation control to improve regional governance and balancing the configuration of spatial development right to achieve mobile spatial governance are feasible paths for multi-scale rural space governance. In conclusion, clarifying the multi-scale rural spatial characteristics in the new era and constructing a scientific governance system could provide theoretical support to promote integrated urban-rural development and rural vitalization strategy.

Most of Asian major international rivers originate from China. Their abundant transboundary water resources play an important role in regional "water-energy-food-ecology" security. In recent decades, influenced by global change, especially by the construction of large hydraulic and hydroelectric engineering, the changes in hydrological and ecological processes and their transboundary impacts in the international river regions have attracted more and more attention. The research on these issues in China has achieved prominent results in several aspects, including the changes in hydrological and ecological processes and their attributions, the transboundary impacts and risk regulation, the "water-energy-food-ecology" nexus in transboundary watersheds, and the construction of transboundary water resources coordination mechanism to adapt to global changes. In the face of the increasing risks of transboundary water security and ecological security under global change, the hydro-geographical research on international rivers needs to make use of space-air-ground integrated monitoring technology, modern spatial geographic information technology, intelligent technology, and so on. By providing quantifiable, participatory, and public results, these researches can better provide scientific basis and decision support for the rational utilization of international rivers and geopolitical cooperation, health maintenance and risk control, transboundary water diplomacy and environmental diplomacy.

The transition from fossil energy to renewable energy will change the structure of global energy geopolitical power structure, national relations, and the driving factors of geopolitical game, which will have a far-reaching impact on the geopolitical shaped by fossil energy. On the basis of combing the origin of energy and geopolitics, this paper expounds the internal logic of the energy transition to reconfigure geopolitics and provides an outlook on the geopolitics of the energy transition. The conclusions are as follows: (1) The connotation and attributes of energy, as well as the differences between energy and geopolitics, determine that energy geopolitics presents significant intergenerational transformation characteristics. (2) The competition for key minerals, the game of low-carbon technology, the reconstruction of geopolitical pattern and the global energy governance are the four dimensions of the geopolitics of energy transformation reconstruction, of which the competition for key minerals is the basis of the geopolitical game of energy transformation, the game of low-carbon technology is the new focus of the geopolitics of energy transformation, and the reconstruction of geopolitical pattern is the direct characterization of the geopolitics of energy transition, energy governance is the path to ease the geopolitical game of energy transformation. (3) In the process of energy transformation and reconstruction of geopolitics, the competition for key minerals, the game of low-carbon technology, the reconstruction of geopolitical pattern and global energy governance are interrelated and interacted, which aggravates the complexity and uncertainty of energy geopolitics in the era of renewable energy. (4) Looking forward to the future, to better promote the development of energy geography and serve the major strategic needs of national energy security, the geopolitical research of energy transformation urgently needs to strengthen the theoretical innovation of energy transition reshaping geopolitics, promote the quantitative research of the geopolitical impact of energy transformation, construct the path of China's deep participation in global energy governance, and pay attention to the energy security issues caused by energy transformation under the background of "carbon neutrality".

The Arctic is undergoing unprecedented climatic and terrestrial environmental changes. The Arctic primary industry has experienced a wide and significant effect from these shifting environmental factors, such as rising temperatures, greening vegetation, thawing permafrost, and frequent wildfires. It is essential to integrate the knowledge of impacts caused by climatic and terrestrial environmental changes on Arctic primary production in order to support the sustainable development of primary industry and inform the formulation of industrial policies. The four main sectors of primary industry (cultivation, livestock husbandry, forestry, fishery and aquaculture) were discussed in this work. This study synthesized the types and extent of the impacts caused by climatic and terrestrial environmental changes on each sector, and provided a summary and outlook from five aspects with a cross-sector perspective: (1) the specific ways of climate changes affecting primary production; (2) the challenges of integrating knowledge from local researches; (3) the enactment and implementation of adaptation strategies; (4) the demand for integration and innovation in data and methods; and (5) the inspiration of the climate change-induced alteration in Arctic primary industry for China. This study concluded the priorities of researching the impact of climate changes on Arctic primary industry, and the results would be capable to aid China's participation in the sustainable development of Arctic primary producing activities.

The social integration of urban floating population is the key task of the new-type urbanization in China. In view of the deficiencies of existing studies on the spatial characteristics of social integration and the role of destination city (place of inflow) factors, based on the China Migrants Dynamic Survey in 2017, this paper employs spatial analysis and hierarchical linear model to reveal the spatial pattern and influencing mechanism of social integration of migrants in cities above prefecture level in China. The results show that: (1) the overall social integration index of China's urban migrants is 0.43, which has the dimensional characteristics of behavioral integration (0.71) > psychological integration (0.61) > economic integration (0.33). (2) The social integration of migrants has spatial autocorrelation and agglomeration. The high-level social integration areas are mainly distributed in Northeast China, Shandong Peninsula, and Sichuan and Chongqing, and the low-level social integration areas are mainly found in the southeast coastal areas, Guanzhong Plain and North China Plain. These regions have the basic characteristics that the social integration level of migrants in small cities with a population of less than 0.5 million is higher than that in large cities. (3) Both the destination city and migrant individual factors jointly affect and shape the level and spatial pattern of migrants' social integration. Moreover, it is found that the population size, house price level and public services in the destination city regulate the impact of individual factors by four regulatory mechanisms: positive polarization, negative polarization, positive homogenization and negative homogenization. This paper calls for the research on the social integration of migrants from the human-land interaction perspective highlighting the relation of destination-individual factors to reveal the effect of destination factors on individual factors. This approach can provide a place-based policy implication for promoting the construction of new-type urbanization in China.

Climbing dunes are important barrier dunes that are widely distributed in highland mountain regions, and their formation is mainly controlled by topography, sand sources and wind regime. Existing researches mainly focus on simulation experiments, distribution patterns, field observations, and morphological characteristics. From a regional scale, there is a lack of research to analyze the variations in sediment characteristics and environmental significance of climbing dunes in different climatic regions. In this study, the wind regime, near-surface airflow, sediment characteristics and material sources of climbing dunes on the Qinghai-Tibet Plateau were comprehensively analyzed from the aspects of aeolian geomorphology, grain-size sedimentology, and geochemistry. The results show that: (1) Due to differences in material sources, the grain-size composition of climbing dunes sediments in different climatic areas varies, primarily fine and medium sands, with good sorting in the semi-humid areas and poor sorting in arid areas. The grain-size difference of sediments in different geomorphic parts is small, and it responds well to near-surface airflow, and in-situ sand accumulation is the basic formation form, with fine sand having the strongest climbing ability. (2) The chemical element content of sediments is influenced by the parent rock characteristics and the climatic environment, and the particle size is also important to its spatial variation, and trace elements are primarily concentrated in river floodplains, with little variation between geomorphic sites. (3) Except for SiO₂ enrichment, all macronutrients in the sediment show varying degrees of leaching or enrichment, and the majority of trace elements are deficient, as leaching and enrichment are closely related to particle size. (4) Climbing dunes sediments are in the early stage of continental weathering, with higher weathering levels in the semi-humid zone. The weathering of sediments in different geomorphic sites varies substantially, which is related to the parent rock, climatic environment, and grain size.

The study of influencing mechanisms of intercity knowledge collaboration networks is an important research topic of innovative geography. Most existing research focuses on the influence of exogenous forces (e.g., urban resources endowment, multidimensional proximity), whereas less attention has been paid to endogenous factors (e.g., preferential attachment, transitivity). This research constructs an intercity knowledge collaboration network of Chinese cities based on the co-publication data from the Web of Science, analyzes its evolving characteristics of spatial and topological structures from 2006 to 2016, and quantitatively explores the endogenous and exogenous forces underlying the network formation through exponential random graph modelling. The results show that: (1) From the spatial structure perspective, the intercity knowledge flows are dense in the eastern region but spare in the western region, which is stable during 2006-2016. The overall network has developed from a dual-core structure of Beijing and Shanghai to a polycentric structure, in which five national-level urban agglomerations have become important bases for nurturing multiple centers. The nodal regions centered on highly administrative cities have become increasingly consistent with the planned urban agglomeration, which plays the dual role of proximal spillover and remote interaction of knowledge resources. (2) From the topological structure perspective, the scale and density of intercity knowledge flows have increased significantly, and the preferential attachment to big cities is obvious. However, with the rise of multiple centers, the network polarization and disassortativity have been weakened. With the optimization of intercity knowledge collaboration paths, the network cohesion has improved, thus becoming a small-world network. (3) From the influencing mechanism perspective, self-evolution and preferential attachment are important driving forces of knowledge collaboration networks, showing an overlapping effect with urban hierarchy. The positive impact of urban knowledge-related attributes on intercity flows is weaker than multidimensional proximity and path dependence. The presence of high-speed railways promotes knowledge collaboration, while the influence of geographic distance is not significant.

As people's needs shift from the material level to the spiritual level, the safety perception of city is increasingly important to the sound development of society. In the meanwhile, there are group differences in the spatial distribution of safety perception, and understanding these differences and their environmental influences can help to respect and meet diverse needs during the process of urban planning and management. Previous research mainly focused on safety perception of residents in their home area, while few studies have investigated the safety perception of different groups outside their residential area. Besides, how environmental factors affect the group differences of their safety perception maps is unclear. Based on current deficiencies, a survey including 1149 participants was carried out in central area of Guangzhou to collect different safety perception maps of three income groups. Negative binomial regression models were used to test the environmental impact on the spatial distribution of safety perception of different income groups, with the environmental factors selected from three aspects: built environment, socioeconomic environment and environmental disorganization. The results show that: (1) long-distance transport facilities such as railway station and coach station, the junction area of Guangzhou-Foshan, and business districts in old city are all marked as high-risk perception area among three income groups. (2) There are certain differences in the spatial distribution of safety perception of the three income groups, among which the safety perception map of the low-income group is significantly different compared to two other groups. (3) Environmental factors such as the distribution of important transport facilities, blue space, land use diversity and intersection density have significant influence on the safety perception map of all income groups. (4) Density factors such as density of entertainment facilities and commercial buildings have a greater impact on the sense of safety of low- and medium-income groups. Design factors like sky openness and green space proportion have more impact on the median- and high-income groups. The impact of socioeconomic level and environmental disorganization factors (e.g., density of police station and instability of passenger flow) present great differences among three income groups. The study can provide theoretical reference for the construction of urban safety environment, establishment of safety image, as well as for humanistic and detailed urban planning and management in the future.

Economic globalization has reshaped the world economy's spatial pattern while simultaneously changing the context for developing economic geography theories. This study revisited the changing features of economic globalization and investigated its geographical implications. Next, it summarized the new trends in economic geography studies in response to the changing economic globalization. Lastly, this study proposed a research agenda for domestic economic geography studies by combining the requirements of global trends and national strategies. The main findings include the following: The scale of geographical integration during economic globalization keeps shrinking, leading to a pattern of regionalization. The driving forces of economic globalization have gradually shifted from cost-saving to innovation. Accordingly, the benefits of economic globalization will be reallocated between developed and developing countries. The trade-offs between efficiency and resilience alter the global value chain, shifting outsourcing from off-shoring to re-shoring or near-shoring. The changing economic globalization has witnessed the rising effects of geographical distances, institutions, and resilience on increasing the inequality of the global economic geography. In economic geography, the scalar structures shifted from the global-local to the global-national-local. The relational networks evolved toward a multi-level, multi-agent, and multi-scale one. The role of the nation has been revisited. More attention has been paid to geopolitical hotspots. Overall, economic geography's institutional, cultural, relational, and evolutionary turns exhibit an emerging trend to convergence. In such a setting, domestic economic geography should find a new balance between global trends and national strategies. This study proposed seven research issues, including: (1) the practice of the Belt and Road and the pattern of inclusive globalization; (2) the economic geography of dual circulation; (3) the paths and resilience of regional development in response to the global production network restructuring; (4) the evolution and competitiveness of industrial clusters; (5) the building of multi-level innovation systems; (6) the regional sustainable development within the global environmental governance system; and (7) the impact of geo-economics on national economic security and interests.

Governing the country is a matter of routine and people-oriented strategy, and improving the people's well-being is "the greatest thing in the country". At present, China is facing the challenge that the national well-being declines with the economic development. This study is based on the national large-scale regional space and adopts the survey data collected in 2020 by the "China People's Livelihood Survey" research group of the Development Research Center of the State Council. The data cover 31 provincial-level regions (hereafter provinces) across the country, including 164 cities at prefecture-level and above, and the number of valid samples is 26370. The research adopts the methods such as the trend surface analysis and spatial analysis of hotspots and coldspots to construct the spatial differentiation and agglomeration pattern of urban residents' perceptions of living conditions in the 31 provinces; the multi-level regression model is used to explore the multi-dimensional influencing factors of perceptions of living conditions at the individual and city levels. The findings are as follows: (1) The differentiation of the living improvement, living condition evaluation, future life confidence and perceptions of living conditions of urban residents in China shows a pattern of high in the west and low in the east, and high in the south and low in the north. (2) The living conditions of urban residents show the characteristics of "continuous agglomeration", and the evaluation of living conditions shows the characteristics of "coexistence of massive agglomeration and scattered distribution", and shows the characteristics of high in the south and west and low in the north and east together with the future life confidence and overall perceptions of living conditions. (3) On average, the highest and lowest values of life improvement, urban residents' living condition evaluation, future life confidence and perceptions of living conditions are also located in the west and east respectively. (4) The influencing factors at the individual level are reflected in gender, age, education level, employment status, household registration status and satisfaction evaluation of urban public services. Among them, satisfaction evaluation of urban public services is reflected in government services, social security status, fair law enforcement status, food safety status, housing status, education status, medical services, transportation status, environmental status, etc. (5) The city size has a significant impact on the perceptions of living conditions of urban residents. Compared with large cities, the perceptions of living conditions of residents in small and medium-sized cities is higher, while that of residents in megacities is lower. In addition, the positive impact of satisfaction evaluation of public services in megacities on the perceptions of living conditions of urban residents has been weakened. Specifically, it mainly weakens the positive correlation strength of medical status evaluation and traffic status evaluation on the well-being effect. The research provides a practical and theoretical reference for the research, judgment and governance direction of China's national perceptions of living conditions.

Remote sensing in hydrology is a crossing field of hydrology and remote sensing. It not only includes remote sensing retrieval models for water cycle factors, but also covers remote sensing hydrological models which serve for calculating the process of hydrology. This review focuses on the past, present and future development of remote sensing hydrological model by using the meta-analysis method and collecting related research in the past 40 years. The results show that remote sensing hydrological model has played a key role in remote sensing hydrology since the 1970s in the world. In China, the researchers of remote sensing in hydrology keep pace with global scientists, and prominent achievements include the concept generation about the remote sensing hydrology, promotion of the combination between remote sensing and hydrology and development of remote sensing hydrological models. In the future, by the help of enhanced information technology, the remote sensing hydrological models will pay more attention to the runoff monitoring by using remote sensing, the intelligent web of hydrological sensors, hydrological analysis in the data scarce watersheds, and the precise simulation of the water flow, water quality as well as the water ecology.

Water retention plays a critical role in terrestrial ecosystem service. However, regarding its definition and calculation, there is a long debate in academia, which illustrates its importance in practice, and simultaneously demonstrates the complexity and vagueness of this essential concept. Thus, there is an urgent need to clarify its definition and calculation method based on basic ecological and hydrological theories, and eventually promote science-based decision-making and integrated water management. Interestingly, we observed that for the same term of "water retention function", ecologists intended to concern the terrestrial ecosystem's water storage capacity (S_max), while hydrologists concerned more about the water yield from the catchment (Q). Both perspectives have their own rationality, but with totally different vision and emphasis. By theorical discussion and data analysis, we found that water storage capacity (S_max) and water yield (Q) indeed have strong connection, but they are definitely two different concepts. The S_max of terrestrial ecosystem determined the separation of precipitation into either evaporation (green water) and Q (blue water). The size of S_max in most cases trades off with the amount of Q. We further revealed that the root zone storage capacity (S_Rmax) of ecosystem is at the heart of water retention function assessment, and plays a key role linking blue and green water. The S_Rmax is the result of ecosystem's adaption to its climate, and can be derived by the classic method to design reservoir, i.e. the Mass Curve Technique (MCT). Lastly, we gave three recommendations: (1) simultaneously evaluating green water retention capacity and blue water yield in practice; (2) further investigating the water retention functions of more water bodies, e.g. glacier, snow cover, and groundwater; (3) synergizing natural and artificial water retention capacities to enhance the water use efficiency in both the ecosystem and our economic-social system.

Senior residential tourism is the product of upgrading demand for elderly care, and thus effectively fits the national development strategy of rural revitalization. Based on grasping the connotation of senior residential tourism, the paper constructs a framework to analyze the development of senior residential tourism with the push-pull theory. This paper uses various analytical methods to discuss senior rural residential tourism's spatial and temporal evolution pattern and formation mechanism, and further reveals and analyzes the typical development mode. The findings are as follows: (1) Senior residential tourism is a lifestyle in which the elderly live continuously in the sojourning place for the dual purpose of deep experience and living. To grasp its connotation, it is necessary to clarify the key issues, such as the subject of action, the motive of action, the time limit, and the moving distance. (2) In terms of temporal dimension, China's senior rural residential tourism has experienced three stages, namely, the budding stage, the slow development stage, and the high-speed development stage, which show a trend of structure type optimization, increased participation of social capital, and market development segmentation. (3) In terms of spatial dimension, senior rural residential tourism development strongly correlates with the "Hu Huanyong Line." During the study period, the high-density core area evolved from the "single-level core" of the Yangtze River Delta to the "three-pillar" situation of the Yangtze River Delta, Beijing-Tianjin-Hebei region, and Pearl River Delta. (4) Under the framework of "push, pull, and intermediate barrier", the development of China takes the pulling force as the dominant driving force, which mainly includes the number of intangible cultural heritages, the number of tourist resorts, and other factors. (5) Finally, based on the comprehensive analysis of regional development factors, this paper classifies senior rural residential tourism into four typical development modes: natural support, cultural tourism support, health support, and mixed type, and thus puts forward a development path according to local conditions and classification.

According to the strategic direction of urban-rural integration and rural revitalization, the spatial reconstruction of rural settlement system is the spatial organization foundation of future urban-rural integration development. This paper focused on the hierarchical scale and spatial organization characteristics of the rural settlement system. It comprehensively revealed the evolution process and regional characteristics of rural settlement systems of 111 administrative units in Guangdong province from 1990 to 2020, and discussed their evolutionary mechanism and spatial optimizing and reorganizing regional modes. The results show that: (1) There were significant regional differences in the hierarchical scale distribution of the rural settlement system in Guangdong. The patches of rural settlements show the characteristics of concentric aggregation and distribution centered on the geometric barycenter of each administrative unit. The spatial distribution pattern of the rank cumulative size coefficients of rural settlement system was "high in the southwest, but low in the northeast" and "high in coastal areas, and low in the inland". The decreasing region of the rank cumulative size coefficient was concentrated on the east bank of the Pearl River Estuary and coastal areas of eastern Guangdong, while the increasing region was mainly distributed on the west bank of the Pearl River Estuary. (2) The influencing factors such as natural background, economic development, urbanization development, transportation and location, institutions and policies jointly drove the development and evolution of the rural settlement system. Rural settlement system of urban areas is small in scale in the mature stage of urbanization, which will gradually die out and integrate into the city. Driven by urbanization, industrialization and policies, rural settlement system of suburban areas has experienced survival of the fittest and maintains a stable scale, but the mixed distribution of urban and rural land makes the spatial organization of rural settlements increasingly loose. Driven by the continuous outflow of production factors, exurb rural settlements appear to be "hollowing out". The villagers returning to build new houses and the lack of homestead exit mechanism have led to a continuous and stable growth in rural settlement scale, and their spatial distribution is characterized by more peripheral diffusion. Rural settlement system with poor location in mountainous areas develops slowly under the support of policies, and the aggregation characteristic along the transportation line is significant. (3) Facing the integrated development of urban and rural spaces, four models of spatial optimization and reorganization of rural settlement system are proposed: urban-rural integration development, dual-core-driven development, central place hierarchical system development, and pan-center chain-connecting cluster development.

As global temperatures continue to rise, the impact of water availability on vegetation productivity remains unclear. This study aims to assess the long-term trends of vegetation productivity response to wet and dry changes and the time-scale thresholds of vegetation response in China from 1982 to 2018, which will be important for reducing the management costs of terrestrial ecosystems and achieving the goals of carbon peaking and carbon neutrality. Results show that: (1) Water stress on vegetation productivity in China has increased throughout the study period. (2) In multiple time scale dry and wet variations, 61.18% of the vegetated cover areas had water deficit significantly inhibiting vegetative photosynthesis. In contrast, 28.29% of the vegetated cover areas had water surplus significantly inhibiting vegetative photosynthesis. (3) The minimum response time for vegetation productivity significantly stressed by aridification has been shortened, while the maximum response time for vegetation productivity significantly constrained by water surplus has been lengthened. These observations indicate that it became easier for aridification to suppress vegetation productivity effects and more difficult for the water surplus to produce suppressive effects on vegetation productivity. Consequently, the water constraint on vegetation productivity in China has been intensifying over the past 37 years. These findings shed light on the evolving trend of water availability in the face of ongoing climate warming, providing a scientific basis for understanding the coupling relationship between water and carbon, as well as the water-carbon cycle.

Despite the initial development goals achieved, China's macro-economy is still deeply affected by the external environment and stuck in its own structure at the same time. In retrospect, not until 1949 with the founding of the People's Republic of China did China's budding regional economy witness the prominence of a fixed development pattern shifting from a spontaneous to an actuating one. After comparing the three regional economic practices, this paper finds that each development stage has its corresponding development strategy. At the same time, several development patterns, namely, the coastal and inland areas, the three regions, and four plates were formed accordingly. Furthermore, through combing the literature and historical facts, this paper determines the historical starting point, division criteria and division scheme of China's regional economic development before summarizing three main lines and also contradictions therein: the government-market relations against the background of market reform, the coastal-inland relations against the tide of economic zonation, and the urban-rural relations against the trend of urbanization. Based on the above, the paper constructs a three-dimensional model out of the spatio-termporal process of China's regional development before proposing new historical stages from the perspective of economic system modernization. These historical stages are: industrial economy, special zone economy, district economy, regional economy and urban network economy. Finally, from the urbanization angle, this paper concludes that for different urbanization stages, regional policies should be industrial policies, factor policies, fiscal and tax policies sequentially.

Based on the quasi-natural experiment, this paper uses the method of time double difference (DID) to empirically test the differential impact and mechanism of the opening of China Railway Express on the export trade of cities along the rail line by using the panel data of 279 prefecture-level cities in China from 2004 to 2019. The results show that: (1) The opening of China Railway Express has significantly promoted the export trade growth of cities along the rail line in China. The better the local transportation infrastructure conditions, the stronger the driving effect on the growth of local export trade. Exports are also positively regulated by the number of countries passing through and the logistics transportation capacity of the destination country. (2) Heterogeneity analysis found that the opening of the train has a significant positive impact on the export trade of the node cities of the supply hub, but it has no significant impact on the railway hub cities, and has a certain inhibitory effect on the export of the port cities. From the perspective of city size, the positive promotion effect of trade mainly occurs in small and medium-sized cities. Based on the analysis of different geographical location train channels, it is found that the promotion effect on the export trade growth of cities along the western channel is obvious. (3) The organization and operation of China Railway Express follow the "axle-spoke" mode, and their radiating space to the surrounding areas is roughly within 150 kilometers. The intermediary mechanism test shows that the opening of China Railway Express can promote the growth of export trade by improving the regional marketization level, and the positive intermediary effect of marketization level is more significant for cities in peripheral regions. The intermediary effect of transportation time cost saving is not significant, and the saving of time required by traditional shipping is not the main reason to promote the growth of export trade.

Ladakh is located in the northwest of the Qinghai-Tibet Plateau, the western section of the Himalayas, and the upper reaches of the Indus River valley. It is now part of Indian-controlled Kashmir. Since ancient times, Ladakh has been the "key point" from northwest South Asia to the Ngari Prefecture of Xizang and southern Xinjiang. However, most existing research on Ladakh focuses on its local history and culture. Although there are some related works on geopolitical relations, few have studied the historical changes of this region and its subordinate relationship and geographical value with China over a long time scale and analyzed the geographical significance of Ladakh. At the same time, some erroneous views and geographical maps have been disseminated on the Internet at home and abroad, which urgently needs a comprehensive correction from the academic level. Based on a variety of historical documents, map data, and a detailed review of previous research results, this paper demonstrates the changes in place names, historical evolution, and regional scope of Ladakh from the 1st to the 21st century and analyzes its significance in the homeland security of western China. The results show that: (1) As the native land of China's Xizang Ladakh was part of the Tubo Dynasty until the 9th century. After the collapse of the Tubo Dynasty in the middle of the 9th century, Ladakh was an essential part of the Ngari local administration established by the descendants of the Tubo Royal family. In the 13th century, Ladakh was again united within the territory of China's Yuan Dynasty and continued through the Ming and Qing dynasties. It remained until the mid-19th century when the Prince-state of Jammu in southern Kashmir invaded it and incorporated it into the British Indian colony. It was then occupied by the Indian army in 1947. (2) Ladakh region has a tortuous history with many changes in place names. However, when Jammu annexed it in modern times, Ladakh only referred to the upper reaches of Indus Valley between the Western Himalayas and the Karakoram Mountains, with Leh as the center. (3) The complexity of the historical and geographical processes in the Ladakh region makes it the central area of conflicts created by India in the western section of the China-India border. Therefore, China should adopt active strategies to avoid India's continuous "assimilation" policy.

Understanding the geographical pattern and driving factors of China's population migration in the first 20 years of the 21st century has become a pivotal issue in promoting the construction of the new-type urbanization and interaction development between regions during the 14th Five-Year Plan period (2021-2025). Supported by the data of the sixth and seventh national population censuses and 2005 and 2015 national 1% population sample surveys, this paper aims to investigate the spatiotemporal evolution characteristics and influencing factors of interprovincial migration in China from 2000 to 2020. Relevant population geospatial analysis and the eigenvector spatial filtering Poisson pseudo-maximum likelihood estimation (ESF PPML) gravity model are employed. The following conclusions are drawn: (1) China's population migration patterns were generally stable from 2000 to 2020, where notable imbalance and network spillover effects were also detected. A large number of migrants from central, western and northeast parts of China tended to move to the eastern region. (2) The overall migration patterns between 2000 and 2020 revealed several changing characteristics. The degree of imbalance and spatial agglomeration of migration patterns gradually weakened. Yet, a north-south differentiation emerged. It is also found that the out-migration trend of the northeast region increased with the elaspe of time. (3) The ESF PPML model indicated that gravity factors (population scale, geographical distance), regional socio-economic factors (wage disparity, proportion of investment in science and technology and education, medical care), social network factors, environmental comfort (PM_2.5 concentration) and living costs (proportion of housing price) drove the interprovincial migration pattern between 2000 and 2020. (4) The influence of regional economic differences on interprovincial migration reflected a weakening trend. The pattern of population migration gradually turned into the decision-making of diversified demands for the economy, public services and urban amenities, while the living cost factor represented by housing price had played a gradually significant part. The conclusion of this paper provides policy references for the construction of the new-type urbanization and coordinated development between regions during the 14th Five-Year Plan period in China.

Coastal wetlands, a pivotal realm of sea-land interactions, exhibit profound ecological sensitivity. Increasingly shifting climatic patterns and intensifying anthropogenic interventions pose formidable challenges to the sustainable utilization of these invaluable assets. Cultural ecosystem services (CESs) represent a subtle, yet crucial conduit connecting the natural environment and human society, thereby playing a pivotal role in the holistic management of coastal and oceanic domains. This study employed the theoretical framework of CESs involvement in the sustainable management of coastal wetland resources, and integrated multi-sourced social media data with the MaxEnt model to conduct an empirical investigation focused on nine Chinese coastal wetlands which are listed in Ramsar Convention. The results reveal the following: (1) From the mean level of each CES, the coastal wetlands with the strongest capacity for biodiversity, historical, educational, and recreational service respectively was the Guangxi Shankou Mangrove Wetland (0.222), with a high level area of 61.218 km², accounting for 27%; Fujian Zhangjiangkou Mangrove Wetland (0.336), with a high level of 9.037 km², accounting for 17%; Tianjin Beidagang Wetland (0.092), with a high level of 70.981 km², accounting for 11%; and Fujian Zhangjiangkou Mangrove Wetland (0.350), with a high level of 9.037 km², accounting for 17%. (2) Delineating the spatial differentiation pattern of each CES, the high-level zone for biodiversity service in Shankou Mangrove Wetland is predominantly clustered within the eastern and central regions. A high level of historical service was more significant in the western and eastern Fujian Zhangjiangkou Mangrove Wetland. Regarding educational service in the Tianjin Beidagang Wetland, high-level areas were clustered in the western sector. The high-level recreational service areas of the Zhangjiangkou Mangrove Wetland were mainly clustered in estuarine area. (3) Assessing the contributions of environmental variables to CESs, it became evident that distance to nature reserves, land-use type, and distance to bird habitats emerged as the principal factors steering the divergences in biodiversity service patterns. Simultaneously, distance to infrastructure, roads, and bird habitat proximity significantly influenced the historical, educational, and recreational services within the nine coastal wetlands, albeit to varying extents. (4) In line with both regional and national strategies, this study categorised sustainable resource management approaches for the nine coastal wetlands into three distinct modes: ecological restoration, ecological and cultural rejuvenation, and ecological and industrial integration, thereby presenting innovative paradigms for the research and implementation of comprehensive governance within China's coastal and oceanic domains.

With the increasing global warming over the past three decades, the climatic zones and eco-geographical regions characteristics in China have changed. This study used the climatic data of 641 meteorological stations over the past three decades (1991-2020), as well as the high-precision data of eco-geographical elements to optimize the eco-geographical regions in China. The study updated the map of eco-geographical regionalization in China (2023) and increased the scale to 1:4000000. The new map divided China into 11 temperature zones, 22 dry and wet regions, and 50 natural regions. The results show that compared with eco-geographical regionalization in 2007, the overall pattern of eco-geographical regions in China has not changed significantly over the past three decades, but the boundaries of temperature zones, dry and wet regions, and eco-geographical regions (natural regions) in some areas have changed to some extent. Firstly, the boundary change of temperature zones is more obvious in the east. Particularly, in the middle and lower reaches of the Yangtze River, the northward shift of the temperature zone boundary between the northern subtropical and the mid-subtropical zones is obvious. Secondly, the boundary between dry and wet regions has changed, and that between semi-arid and arid regions in the north of the second-order landform step has shifted slightly to the west. In addition, the boundary between semi-arid and sub-humid regions in the Qinghai-Tibet Plateau has shifted slightly to the southeast, reflecting a slight expansion of the scope of semi-arid regions. Finally, boundary changes in natural regions in some areas vary greatly. This study can provide a macro-regional framework for guiding ecological conservation and restoration in different regions.

GIScience inherits the spatial analysis tradition of geography. Given that "spatial is special", GIScience needs to highlight spatial effects when constructing methods for geographical analysis. The research presents an explicit definition of spatial effect. By formalizing core GIScience concepts including space, location, field, distance, and region, we identify four types of spatial effects, namely spatial heterogeneity effect, neighbor effect in spatial dependence, distance decay effect in spatial interactions, and scale effect in spatial zoning. A unified framework is constructed to cover the four spatial effects based on the inherent linkages among them. We argue that spatial heterogeneity effect is the most fundamental one. While spatial dependence and spatial interaction are two basic geographical processes that represent the second-order relationships between two locations, neighbor effect and distance decay effect reflect the impacts of space. Scale effect is raised when aggregating attributes using regional units. Hence, the four types of effects form a hierarchical system. From a methodological perspective, this paper summaries related GIScience tools that implement different effects, and emphasizes the value of geospatial artificial intelligence for revealing and quantifying spatial effects.

As China's urbanization has entered the middle and later stage and the improvement of well-being of residents has become a core goal, the transformation from "top-down" system goals optimization on the supply side to "bottom-up" multi-dimensional goals coordination on the demand side has become a new perspective to understand the connotation of urbanization. Based on the perspective of the human living conditions, the humanities environment, and human-city relationship, this paper constructs a connotation framework and index system of urbanization. Furthermore, Theil index is employed to analyze the spatio-temporal differentiation characteristics of China's urbanization before and after the implementation of the new-type urbanization strategy. Finally, in terms of both direct and indirect effect mechanisms, the mechanism framework of urbanization differentiation is constructed, and its evolution pattern is revealed by using Variance Decomposition and Geodetector. The results show that: since the implementation of the new-type urbanization strategy in 2014, China's urbanization has made remarkable achievements, with a steady improvement in human living conditions and human-city relationship, and there is still much room for improvement in the humanities environment. The high-level areas of urbanization are mainly distributed in coastal areas, and expanding to inland areas along the Yangtze River Basin and Yellow River Basin. The regional differences of urbanization gradually decrease, but the contribution rate of inner-regional differences shows an expanding trend. Differences in human living conditions and human-city relationship are the main factors of urbanization differentiation, but the contribution of differences in humanities environment is gradually expanding after 2014. Opening up and scientific & technological innovation are the main influencing factors of the difference in human living conditions. With the implementation of the new-type urbanization strategy, the impact on differences in humanities environment of the government finance gradually diminishes. Resource endowments have a relatively strong influence on differences in human-city relationship. This study can provide theoretical and empirical support for promoting the development of urbanization in China.

Mountain altitudinal belts are the miniature of horizontal differentiation and succession of climatic and vegetational zonation. However, altitudinal belts' vertical range, transition model, inner structure and combining pattern vary from place to place. In Mt. Taibai of the central section of China's north-south transitional zone, we have found an altitudinal belt with the largest range in the world, namely, the montane deciduous broad-leaved forest, which extends continuously from the mountain base to about 2800 m, including basal oak belt, typical oak belt of two sub-belts and cold-tolerant pioneer birch belt of two sub-belts, which could otherwise develop independently. Characterized by a "three layers and five sub-belts" structure, this "super altitudinal belt" is much vertically broader than the threshold of 1000 m for normal altitudinal belts. Its formation is closely related with its transitional geographic location, integral spectrum of altitudinal belts in central Qinling Mountains, rich and diverse species of deciduous woody plants, and their strong competitiveness. The finding of the super altitudinal belt has multiple significance: Its existence is another significant physio-geographic feature of China's north-south transitional zone; it shows that an altitudinal belt may have rather complex inner structure and broad vertical range in some special mountain environment. This broadens our understanding of altitudinal belt structures and their mechanisms, and is of great significance for developing structural theory for montane altitudinal belts. This finding also demonstrates that there are many big questions for us to explore and study in the north-south transitional zone, and it is expected that our finding could trigger in-depth study of local climate and biodiversity responsible for the formation of this super belt, and of the complex structure and ecological effect of China's north-south transitional zone.

The water cycle in a river basin has been increasingly influenced by intense human activities along with the progress of human civilization and continuously growing water intake, revealing itself to complex natural-artificial dualistic characteristics. This study elaborates on the origin and development, scientific issues, and framework system of the natural-artificial dualistic water cycle theory in a river basin, as well as the scientific connotation of five dimensional attributes of water resources from the new perspective of dualistic water cycle, i.e. resources, environment, ecology, society, and economy. After that, key technologies based on the dualistic water cycle theory are proposed, and the frontier directions and development trends of research on water resources are summarized. This study intends to promote the research on water cycle in the river basin, hydrography, and the subject of hydrology and water resources.