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.

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".

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.

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.

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.

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.

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.

Nowadays, the disordered expansion of urban land has become an important problem on China's urbanization. Urban population growth is widely recognized as a crucial driver of urban spatial expansion. Therefore, it is necessary to clarify the spatiotemporal differentiation characteristics of urban expansion and understand the relationship between urban population size and urban expansion. Based on Landsat TM/OLI remote sensing images and socioeconomic statistics data, this paper identified the urban land in the Yangtze River Economic Belt (YREB), China, between 1990 to 2020. This was achieved by combining object-oriented automatic extraction and human-computer interaction visual interpretation. The study then examined the spatiotemporal differentiation characteristics of urban expansion at difference scales using expansion speed, expansion difference index, kernel density analysis and spatial autocorrelation. Finally, the relationship between urban population size and urban expansion in different regions was investigated using the Two-way Fixed Effects Model. The main results are as follows: (1) After 2015, urban expansion speed decreased significantly in different parts of the YREB. Moreover, the time series characteristics of urban expansion in the cities of the upper and middle reaches were found to be different from those in the lower reaches. The upper reaches had higher expansion speed than the middle reaches after 2010. Spatially, the urban expansion in the YREB shows significant spatial heterogeneity. High-speed expansion areas have shifted from east to west, and the differences in urban land scale between the upper-middle and the lower reaches tend to converge. Urban expansion in the lower reaches exhibits strong spatial dependency, while in the middle-upper reaches, there is no significant spatial autocorrelation. (2) The relationship between urban population size and urban expansion differs significantly among different regions. The upper reaches show a negative correlation, while the middle-lower reaches exhibit a "U-shaped" relationship. This indicates that there is no obvious over-expansion of population size in the upper reaches, whereas there is in the middle-lower reaches. Residents in the middle reaches have demonstrated a higher sensitivity to urban comfort and quality of life. Finally, the study provides regional policy recommendations, aiming to offer scientific references for targeted urban policies and promote high-quality urban development.

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.

The long historical development process has shaped rural settlements in China with distinct regional characteristics that profoundly reflect the unique geographical environment, history, culture, and lifestyle of each region. Therefore, the comprehensive regionalization of Chinese rural settlement characteristics on the basis of the regional differentiation pattern of rural settlement characteristics is an fundamental research for preserving and transforming the characteristics of rural settlements with adaptation to local conditions. It is also one of the long-term topics in human geographical studies. This study constructs an index system for comprehensive regionalization from four aspects of rural settlement characteristics: earthscape, settlement, architecture, and culture. On the basis of systematic field research results and multisource data, a comprehensive evaluation of rural settlement characteristics is conducted, recognizing the regional differentiation pattern of Chinese rural settlement characteristics. On the basis of its results, a comprehensive regionalization of Chinese rural settlement characteristics is proposed using existing regionalization studies on physical geography, agricultural geography, cultural geography, landscape of rural settlements, and traditional dwellings as references. This regionalization is developed in accordance with the principles of regional conjugacy, synchronicity, coordination of comprehensiveness and dominant factors, and relative consistency. We use the qualitative and quantitative methods of category mapping, spatial cluster analysis, geographical correlation analysis, dominant factor analysis, and overlapping analysis. In the proposed regionalization, China is divided into 12 regions and 82 subregions in accordance with rural settlement characteristics. The 12 regions are as follows: (1) Northeast China, (2) North China, (3) the Loess Plateau, (4) East China, (5) Central China, (6) Fujian-Hakka, (7) Lingnan, (8) Sichuan-Guizhou, (9) Yunnan, (10) Northern Border, (11) Northwest China, and (12) the Tibetan Plateau. The characteristics of rural settlements in each region are also summarized. By comprehensively reflecting on the similarities and differences of the characteristics of Chinese rural settlements at different scales, the proposed regionalization is capable of providing scientific support to the regionalized and classified preservation of characteristic rural settlements.

There are important changes in urban-rural structure of population mobility at the late-intermediate stage of urbanization in China, which will have a significant impact on population redistribution, urbanization and regional development. This paper divides the interprovincial urban and rural floating population into four mobility types by using the 2010 and 2020 censuses data, and on the basis of identifying the mainstream types, their spatial patterns evolution and the relationship with regional economic development are investigated through the mobility ratio indexes and regression models. The study results can be summarized as follows. (1) The urban and rural floating population is large and grows rapidly. Meanwhile, rural-urban mobility keeps the dominant position, and urban-urban mobility rises rapidly, these two population mobility types have become the mainstream ones of interprovincial urban and rural floating population in China. (2) In terms of the net mobility pattern of urban-urban floating population, the net-inflow areas are further concentrated in the three major coastal centers of Beijing, Shanghai and Guangdong, and Liaoning, Xinjiang and Yunnan are also maintained at a certain net-inflow rate, but most of the provincial-level regions are in the net-outflow areas. The major changes of the net mobility pattern of urban-urban floating population have shaped a spatial connection network. The main features of this network can be described as three cross-regional flow circles of Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta in coastal China. At the same time, the space connections within the regions are strengthening in northeast China, northwest China and southwest China. (3) The net mobility pattern of rural-urban floating population shows that in coastal areas, the net-inflow rate rises or decreases during the study period, while in inland areas, the increase in the net-inflow rate of Liaoning and Xinjiang leads to the decline in the net-outflow rate of their neighboring provinces. The changes of the net mobility pattern of rural-urban floating population depict the dual characteristics of continuous formation and different changes of the coastal flow circle, and the development of the inland flow circle in Xinjiang and Liaoning. (4) There is a mutual relationship between urban-urban and rural-urban population mobility and regional economic development. For regional economic development of both population mobility types, the impact is significantly positive and has been increasing. When we add the floating stock into the models, the positive effect of this variable has decreased in urban-urban mobility's model, while it still plays the first-place positive effect in rural-urban mobility's model. The two population mobility types have a positive effect on the national economic development and the inflow areas' economic development.

Soil organic carbon (SOC) storage and soil carbon sinks play a crucial role in the global carbon cycle of terrestrial ecosystem. However, many previous studies of soil carbon storage and sinks utilized low-resolution land use dataset, with limited focus on soil carbon sinks from farmland and grassland management. To address this issue, this study employed a series of accounting models to estimate the carbon sink from farmland and grassland management, the carbon sink from forest management, changes in soil carbon storage, changes in carbon storage due to land use conversion from 2000 to 2020, as well as the soil carbon storage in China in 2000 and 2020 using a 30 m-resolution land use dataset. The results showed that the national carbon sink from farmland management in China was approximately 17.918 Tg C a^-1 and the carbon sink from grassland management was approximately 20.171 Tg C a^-1 during 2000-2020. The carbon sink from forest management in China was approximately 81.622 Tg C a^-1 during 2000-2020. The soil carbon storage (0-100 cm) in China increased from 86.074 Pg C in 2000 to 86.771 Pg C in 2020. The soil carbon storage increased by approximately 34.850 Tg C a^-1 from 2000 to 2020. The land use transformation during the study period resulted in a decrease of approximately 17.621 Tg C a^-1 in soil carbon storage. The findings of this study can help researchers understand China's carbon storage and provide scientific data to China's 2060 Carbon Neutrality Target.

The border issue holds significant importance in China-India relations, persistently hampering their development. Existing scholarship tends to interpret the causes of China-India border disputes through lenses of colonization, history, security and third-party involvement. However, these approaches overlook the complex power dynamics within the state which regards the border as the tools. To comprehensively explore the new-round China-India border dispute since May 2020, this paper cites the thought and methods of critical geopolitics, applies discourse analysis of geopolitical imaginations, and proposes a novel perspective that analyzes the border dispute in terms of the synergetic role of multiple actors. The findings indicate that: (1) The border dispute can be considered as tools or resources for multiple actors to achieve their goals or interests through jointly constructing geopolitical discourses and imaginations related to border disputes; (2) Based on Indian mainstream media news from April 2020 to March 2021, the Bharatiya Janata Party, Congress Party, the military, Ministry of External Affairs and the business and social elites in India have utilized the border conflicts as tools and resources to pursue political and economic interests through three forms of geopolitical imagination: paranoid style, intimate metaphor and moral resistance, thereby exacerbating the dispute; (3) The border dispute from May 2020 to February 2021 is regarded as a continuous process exploited by Indian multi-actors, which means that the conflicts, like the confrontation in Pangong Lake, occurred when the multi-actors' interests were not yet secured, but tend to subside once their interests are largely met. In this regard, China should rationally understand the periodic and persistent nature of China-India border disputes and actively build complementary and cooperative structures between the two countries through positive methods like "appreciative inquiry" which may effectively mitigate or resolve border disputes.

The deciduous broad-leaved forests are a typical vegetation in the eastern monsoon region of China. This work utilizes the fine classification data of surface cover of composite elevation information to extract the upper limit of montane deciduous broad-leaved forests. We examine the distribution characteristics of the upper limit and its factors influencing the montane deciduous broad-leaved forests by constructing cloud models of the upper limit height. Moreover, this work constructs multiple linear regression models (with the upper limit of deciduous broad-leaved forests at multiple scales (regional, mountain, and local) as the dependent variable and the influencing factors as the independent variables), and a weight coefficient cloud model of influencing factors. Furthermore, this work compares and analyzes the scale changes and spatial differences of the effect of influencing factors on the upper limit of deciduous broad-leaved forests. The sensitivity differences of different montane deciduous broad-leaved forest upper limits to climate factors are also explored. Results show that: (1) The upper limit height of the deciduous broad-leaved forest in the eastern monsoon region of China first increases and then decreases from north to south. The expectation (Ex), entropy (En), and hyper entropy (He) of the distribution height cloud model are 965.77-1993.52 m, 132.80-514.09 m, and 27.58-205.34 m, respectively. (2) Significant scale changes can be observed in the impact mechanism of the upper limit of deciduous broad-leaved forests in the mountainous areas: at the regional scale, the dominant factor for non-climatic and climatic forest lines is mountain base elevation, with contribution rates of 71.36% and 44.06%, respectively. The climatic forest line is more affected by temperature than by precipitation. Meanwhile, non-climatic forest line is more affected by precipitation than by temperature. At the mountain scale, the upper limit of deciduous broad-leaved forests in the mountainous areas is mainly influenced by January average temperature and annual precipitation, and the role of January average temperature in most mountainous areas is larger than that of annual precipitation. On a local scale, except for the Dabie Mountains, the mountaintop effect has the highest weight on the upper limit of deciduous broad-leaved forests in each mountainous area (Ex: 44.84%-68.15%). In addition, the expectation weight of annual precipitation (Ex: 15.45%-41.86%) is higher than that of the January average temperature (Ex: 4.3%-9.97%). (3) The deciduous broad-leaved forests in the Dabie Mountains and Taihang Mountains are most sensitive to annual precipitation (Ex: 40.24% and 18.95%; He: 0.96% and 1.89%). Lvliang Mountains are the most sensitive to January average temperature (Ex: 8.31%; He: 1.09%). Exploring the spatial distribution characteristics and influencing factors of the upper limit of deciduous broad-leaved forests in the mountainous areas can promote the study of differences in altitudinal belt response to climate change and provide theoretical support for the construction and management of regional ecological security monitoring systems.

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

The rational flow of urban-rural factors is conducive to optimize the urban-rural relationship and promote rural revitalization and urban-rural integrated development. Based on the theory of social reproduction, this study defined the connotation and flow types of urban-rural factors, proposed the measurement method of urban-rural factor flow, and quantitatively analyzed the spatial pattern and evolution characteristics of urban-rural factor flow in China. The results showed that urban-rural factor flow referring to the changes of factors affecting urban and rural development can be divided into three types of internal flow, mutual flow, and inter-regional flow. Significant spatial differences and a gradual increase of flow intensity existed in the mutual flow of population, capital, technology, and agricultural products between urban and rural China, while great spatial differences were found in the inter-regional flow of population, capital, technology, and agricultural products without conspicuously increased flow intensity. The intensity and structure of urban-rural factor flow were comprehensively affected by adjusting the scale and structure of social reproduction under the regulation of natural resource endowment and human regulation. The free two-way flow between urban and rural areas can be realized from the aspects of selecting reasonable human intervention means and optimizing the allocation of factors in the social reproduction process, according to regional factor endowment differences and factor flow characteristics at different scales.

The interaction between the energy system and human society is the main focus of energy geography research, encompassing multiple dimensions such as economy, politics, environment, and culture. The uneven distribution and spatial flow of energy, as well as its environmental effects, have attracted the attention of geographers, who can also analyze energy issues through unique perspectives and research methods. The study of energy geographies has emerged due to economic activities and geopolitics in the energy system on the earth's surface and has entered a new prosperous stage due to the challenge of global climate change and discussions on social equity. Due to the different stages of development, energy and environmental issues, and academic atmospheres between China and foreign countries, scholars have different focuses on perspectives and research characteristics. Foreign energy geography research started from the study of resource distribution and economic geography, and has gradually formed an academic community under the traction of energy and environmental issues. In the long-term development process, diverse research topics such as energy production networks and energy flows, energy geopolitics and energy security, energy transitions and climate governance, energy justice and energy poverty have emerged, which can provide many useful references for Chinese scholars. Since the mid-20th century, China's research on energy geographies has roughly formed the tradition of "world resource geography" and "sectoral economic geography", and has continued to carry out practical application research based on national strategic needs. Since the beginning of the 21st century, research on carbon emissions and residential energy consumption has gradually been in line with international standards. In recent years, under the background of emphasizing the carbon peaking and neutrality goals, energy transition, and energy security, energy geography has ushered in new development opportunities. However, there are also internal and external challenges. To build the subject of "energy geography", we need to make innovations in theory and methods, consultation and think tank research, popular science communication, and talent team construction based on inheriting valuable traditions.

The construction of urban human settlements is an important content to promote the high-quality development of the Yellow River Basin, and it is also a comprehensive way to realize the coordination of human-earth relations in the watershed. This paper constructs an urban human settlements evaluation index system based on the perspective of "production-living-ecological" function, and comprehensively uses the Grey Relation Analysis-Technique for Order Preference By Similarity To Ideal Solution (GRA-TOPSIS) method, spatial Markov chain, Geographically weighted Random Forest (GWRF) and other methods to analyze the dynamic evolution and influencing mechanism of urban human settlements in the Yellow River Basin (YRB) from 2011 to 2020. The results show that: (1) The urban human settlements in the YRB generally exhibits the positive spatial distribution characteristics of "high in the east and low in the west, high in the south and low in the north", forming a high-value area of the human settlements dominated by Xi'an, Zhengzhou, Qingdao and Jinan, and a low-value area of the urban human settlements dominated by cities of Tongchuan, Zhongwei and Jiayuguan. (2) The dynamic evolution of the urban human settlements in the YRB has significant spatial interaction and dynamic transfer convergence. There is a certain degree of "self-locking" effect of the transfer path at the level of the human settlements. The level of the human settlements usually only transfers between adjacent levels, and the probability of cross-level transfer is small. (3) The human settlements are the result of the comprehensive effects of economic level, environmental quality and social resources. The economic level dominates, while consumption level, air quality, and transportation resources are the main factors that affect the level of urban human settlements. (4) GWRF model can effectively explain the spatial heterogeneity characteristics of influencing factors in the local geographic space. It is expected to become a more effective explanatory tool in the field of human settlements research. This paper deepens the theoretical methods of human settlements research and provides a scientific reference for promoting the construction and high-quality development of the human settlements in the YRB.

Improving rural sustainable development capability from the perspective of perceived resilience is crucial to comprehensively promote rural revitalization. Based on the theoretical connotation of rural perceived resilience, this paper discusses the operational logic of rural perceived resilience from the level of "pressure-state-perception-behavior-response", and constructs an indicator system from the perspective of "state-perception" and "behavior-response" based on the data of farmers' questionnaires in 12 villages in 3 towns, Qufu city, Shandong province in 2020. While evaluating the rural perceived resilience, we use the structural equation model to demonstrate the mechanism of rural perceived resilience. The results show that: (1) Rural perceived resilience refers to the ability of rural system to use rural resources to predict, absorb and adapt to rural change, and promote the restructuring of rural elements and the transformation of production and lifestyle, depending on its level of resource elements; (2) The diversified response of social networks and the state of production and construction have become the main components of rural perceived resilience, while the response path of livelihood diversification and material capital enrichment has not been fully formed; (3) Whether the way the rural system responds to the pressure can promote the transformation of traditional villages to modernization depends on the farmers' perception and behavioral decision-making. The better the farmers' perception of the rural state, the more inclined they are to actively use resources to promote the restructuring of rural elements, and fundamentally realize the transformation and development of villages; (4) We should improve the rural perceived resilience by optimizing spatial governance, promoting the transformation from "state-perception" to "behavior-response", and accurately regulating rural "pressure".

Sedimentary DNA has been widely used in the studies of climate change, ecological function, and environmental archaeology, because it can provide biological dynamic information with temporal dimension in geographical environment. However, the surface processes and impact factors of sedimentary DNA within the catchments are still not fully understood, which limits the accuracy of sedimentary DNA data interpretation. In this study, topsoil DNA concentrations at the Buha River catchment in northwest Qinghai Lake, which was suitable for DNA preservation, were firstly measured based on domestic new sedimentary DNA laboratory. Meanwhile, soil physical and chemical compositions, including grain size, elements, loss on ignition and TOC, were determined. Subsequently, the abiotic factors which had impact on spatial distribution of topsoil DNA concentration were analyzed by combing the status related with climate, vegetation cover, and land use at the Buha River catchment. The results showed that the average concentration of topsoil DNA at the whole catchment was 0.91 μg/g, with the higher values in the middle reaches of the Buha River and its tributary Jilmon River, while the lower ones in the lower reaches near the Qinghai Lake. In addition, topsoil DNA concentrations at the catchment were positively correlated with the contents of clay and organic matter, but negatively correlated with sand content and the intensity of weathering and leaching. Besides, high vegetation cover and frequent grazing activities contributed to the enrichment of the topsoil DNA, while strong weathering and leaching under warm and wet environment, river transportation and crop cultivation reduced the concentration of the topsoil DNA. All the above results provide a scientific basis for an understanding of the deposition processes of sedimentary DNA and their impact factors in the Buha River catchment, which are helpful for revealing sedimentary DNA compositions and evolution processes of ecological environment and human-environment relationship in regions west of the Qinghai Lake.

The study of the new economic geography has paid attention to the polarization and balanced development of urban systems. In reality, however, transport accessibility is subject to great uncertainty in explaining the polarization and balance of the urban system. In fact, the polarization or equilibrium of the regional urban system is not only unique in China, but also a general phenomenon in countries with different development outcomes, political systems and degrees of marketization. From the perspective of industrial heterogeneity, this study empirically analyzes the process and mechanism of the industrial structure of regional central cities on the population growth of neighboring cities in China from 1980 to 2020, and examines the influence of industrial structure on the polarization and equilibrium development of the regional urban system. The results show that, firstly, the manufacturing sector strengthens the spillover effect from the core city and promotes the population growth in neighboring cities, while the service sector weakens the spillover effect and hinders the growth in neighboring cities. Secondly, the manufacturing-oriented cities have relatively small city scale, while the service-oriented cities are relatively large. Therefore, the driving effect of manufacturing-oriented central cities on the neighboring cities is larger, which tends to produce a relatively balanced regional city system. Correspondently, the spillover effect of service-oriented central cities on the neighboring cities is smaller, which tends to form a relatively polarized regional city system. Finally, as the share of services in the industrial structure of central cities continues to rise, China's urban system may become more polarized rather than balanced. Certainly, the higher the proportion of manufacturing in the central city, the more balanced the regional urban system is. In fact, the empirical results show that the industrial structure and the spillover effect of the core city have an inverted U-shaped relationship, i.e. a high proportion of manufacturing or services weakens the driving effect of the core city on surrounding cities. The reasons for this vary. The high proportion of manufacturing and the small size of the central city have a limited spillover effect on the neighboring cities and therefore can hardly drive their growth; while the high proportion of service industry and the negative effect of the service industry on the spillover effect lead to the slow development of the neighboring small-and-medium-sized cities. It is worth noting that because of the significant spatial impact of industry on the urban system, the future regional urbanization strategy should be coordinated with the industrial strategy. More importantly, with the gradual liberalization of the household registration system, industry selection can become an effective policy option for macro-control of the regional urban system.

Population equilibrium development is the valuable guide and ideal pursuit of China's population policy and has significant implications for regional equilibrium development. However, there are still misunderstandings about interpreting population spatial equilibrium, and its scientific connotation requires further explanation and promotion. Population spatial equilibrium gives the meaning of space based on population equilibrium, which can be understood as the spatial equilibrium of population distribution. When other factors remain unchanged, the net migration between regions is zero; that is, the total number of immigrants of each region are equal to its total number of emigrants to achieve the dynamic equilibrium of population distribution among regions. A migration stream will exist between regions in an equilibrium state. Migration and equilibrium can coexist, but the population distribution between regions remains dynamic and stable, and the population spatial distribution structure will not change. Specific conditions cause the inherent stipulation of population spatial equilibrium. The equilibrium point will also change with economic, social, resource, and environmental changes. Equilibrium is a relative concept derived from the instantaneous concept; instantaneous equilibrium is an ideal state in the long term. The population spatial distribution is constantly changing from disequilibrium to equilibrium and from equilibrium to disequilibrium. This paper describes a theoretical model of multi-regional population spatial equilibrium based on the regional wage rate, human climate suitability index, urban crowding degree, and distance. Using the Yangtze River Delta as an example, the study analyzes the equilibrium population spatial distribution under current economic, social, environmental, and population conditions. The study found that the population of the study area is concentrated along the river and the coast, mainly in the south of Jiangsu, along the coast of Hangzhou Bay, and the canal from Nanjing to the north of Jiangsu. By comparing the equilibrium population with the current distribution, the Yangtze River Delta can be divided into quasi-equilibrium, attractive, and repulsive areas. The attractive areas, such as Shanghai, Nanjing, and Hangzhou, have large population agglomeration potential. In contrast, the repulsive areas are mainly located in northern and western Anhui, northern Zhejiang, and other areas close to the quasi-equilibrium area. This suggests that under free migration, the population will further concentrate in the areas of Shanghai, Nanjing, Hangzhou, and southern Jiangsu.

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