International and domestic circumstances have led to new opportunities and higher requirements for the development of geographic science in China. In this paper, we propose a modified disciplinary structure for geographic science in China in the new era. Geographic science in China can be categorized into four secondary disciplines, i.e., integrated geography, physical geography, human geography, and information geography, according to the current situation and expected trends. The tertiary disciplines under each secondary discipline are nearly fully developed, and a few quaternary disciplines under the tertiary disciplines are widely accepted and used in China. We hope this new disciplinary structure can play a breakthrough role in improving the branches of geographic science, promoting the development of emerging disciplines under the framework of geographic science, and supporting national and international development strategies in the new era.
Physical geography, one of the branches of geography, is the basic discipline of geographic science. And it is the scientific foundation of ecology, environmental science and other related disciplines. Physical geography focuses on spatial characteristics, evolution and regional differentiation of the earth’s surface. In the new period of rapid development of social economy, and science and technology, physical geography is more closely and widely connected with human geography and, information geography. This paper analyzed the forming process of the physical geography, expressed sub-discipline structure of integrated physical geography, sectoral physical geography, human living-environment geography, and proposed the development strategy of physical geography and its sub-branch disciplines, key priority of development goals and directions in China.
Human geography is a discipline that studies the formation and evolution of the geographical distribution pattern of human activities. The main research objects of human geography focus on human activities and human-environment relationship. The scientific questions to be answered by human geography cover both natural science and social science, and thus it has distinctive interdisciplinary features. In China, human activities’ economic and social processes play an essential role in explaining the law in human geography discipline as human society development is approaching or has entered the post-industrialization stage. The logic and methods of social science have become important tools through which human geography’s changes in processes and patterns of human geography can be reasonably discussed and adequately understood. The research methodology of human geography shows integration characteristics between natural sciences and social sciences. The outcomes of human geography research reveal scientific laws in geographical distribution patterns and the evolution of human activities. It becomes one of the primary disciplines for both the national and local governments to manage and optimize spatial development and protection patterns. It has wide applications in spatial planning, regional strategy and policy-making, and the modernization of spatial governance. The unique feature in integrating academic research and policy-making applications provides human geography discipline in China a superiority of leading the world in the discipline. Besides integrated human geography, human geography in China has five subdisciplines: economic geography, urban geography, rural geography, socio-cultural geography and political geography. Each subdiscipline has priority and critical research fields and coordinates with the rest of the subdisciplines.
The advent of the information era has resulted in exceptional advances in geographic science. The domain of geographic science has expanded from traditional physical and human geography to physical, human, and information geography, resulting in the emergence of the field of information geography. Three subdisciplines have gradually formed, i.e., geographic remote sensing science, geographic information science, and geographic data science. With a view towards preparing a description of the disciplinary structure of geographic science for the “Development Strategy of Discipline and Frontier Research in China (2021-2035)”, this article summarizes the history, definition, and disciplinary structure of information geography. The strategic layout of the discipline, along with the goals and key directions of priority development fields, are also highlighted. The insights into this new discipline provided in this paper will promote the development and application of remote sensing and geographic information within the framework of geographic science, advancing the synthesis of geographic research and the integrated development of geographic science.
The rapid expansion of China’s urban agglomerations in recent decades has resulted in over-occupied ecological spaces and increased ecological pressure that are restricting healthy regional development. This paper examines the structure and characteristics of distribution of “production-living-ecological” spaces in five mega-urban agglomerations in China: Beijing-Tianjin-Hebei (BTH), the Yangtze River Delta (YRD), Guangdong-Hong Kong-Macao Greater Bay Area (GBA), Chengdu-Chongqing (CY), and the middle reaches of the Yangtze River (MYR). We analyze spatial and temporal variations in the ecological spaces and factors influencing them from 1990 to 2020, and examine the comprehensive ecological carrying capacity and status of ecological spaces in the past 30 years based on the available water resources, regulation of water and air quality, and leisure and recreation. The results show the following: (1) Urban agglomerations in different stages of formation and development represent varying area ratios of “ecological-production-living” spaces. The modes of expansion and evolution of the living spaces are dominated by multi-center combinations as well as the spatial structure of ecological spaces, including barrier, compact, discrete, and fully enveloping spaces. (2) From 1990 to 2020, the area occupied by living spaces in urban agglomerations continued to increase significantly while that of spaces for ecological production decreased. Except in the GBA, ecological spaces have exhibited a trend of increase in area, especially in the past 10 years. The area ratios and spatio-temporal variations in the “production-living-ecological” spaces indicate that the main functions of production and ecological spaces in mega-urban agglomerations have shifted from supply to regulation and culture, and reflect the transition from rapid urbanization to sustainable urbanization in China. (3) The comprehensive ecological carrying capacities of 78.6%, 73.1%, 54.5%, 56.3%, and 25.8% of cities in BTH, YRD, GBA, CY and MYR are severely overburdened. Water supply and the regulation of water quality are the main factors restricting the ecological carrying capacity of BTH and YRD while leisure and recreation services have hindered the capacities of GBA and CY. Policymakers thus need to pay attention to the conservation and rational layout of ecological spaces to reduce the ecological pressure in urban agglomerations. The work here can provide a scientific basis for the green and sustainable development of urban agglomerations as well as the optimized configuration of “production-living-ecological” spaces.
High-resolution mapping and monitoring of national land use/cover changes contribute significantly to the knowledge of the interaction between human activities and environmental changes. China’s Land Use/cover Dataset (CLUD) for 2020 and its dynamic changes in 2015-2020 were developed to extend the CLUD to over 30 years (i.e., the 1980s to 2020 at 5-year intervals) by integrating remote sensing big data and knowledge-based human-computer interaction interpretation methods. This integrating method for CLUD 2020 improved the efficiency of national land use/cover mapping and the accuracy of land use pattern change detection compared to earlier CLUD products, with an overall accuracy of 95%. The intensity of land use change decreased across China in 2015-2020 compared to 2010-2015, although both characteristics of its spatial changes were similar. The cropland area continued to shrink at national scale in 2015-2020, with two regional hotspots including the widespread conversions from dry land into paddy land in Northeast China and the coexistence of widespread land cultivation and cropland abandonment in Xinjiang of Northwest China. Built-up land area continued to expand in China, showing consistency between 2015-2020 and 2010-2015, in which hotspots transited from the surroundings of coastal megacities to the city surroundings of the central and western zones. For natural land, although the woodland and grassland decreased in 2015-2020, its magnitude expanded compared to 2010-2015. In comparison, the water body area in Qinghai-Tibet Plateau increased significantly under the continuous impact of climate change. These characteristics of land use change were closely related to the development strategy of the top-level design of the 13th Five-Year Plan (2016-2020) (e.g., ecological civilization construction and high-quality development).
Eco-environmental sustainability is the basis for sustainable development in ecologically fragile areas. Land consolidation plays an important role in coordinating human-land relationships and achieving economic growth and eco-environment protection. Taking the Loess Plateau as the study area, this paper diagnoses the associated eco-environmental problems and their chain effect. The research results show that the overall eco-environment of the region is still relatively fragile. An eco-environment multi-subject co-management model, a scale-differentiated management model, and an elements comprehensive management model are proposed to improve the eco-environmental management efficiency after implementing land consolidation in the plateau. This paper takes the Gully Land Consolidation Project in Baota district of Yan’an city in Shaanxi province as an example to illustrate the relationship between land consolidation and eco-environmental sustainability in the Loess Plateau. Policy implications for eco-environmental protection in the Loess Plateau are proposed.
The nexus exploration among land use/land cover change, ecosystem services and human well-being has been increasingly crucial in the context of Future Earth. However, the spatial heterogeneity and the entwining process among these three aspects have not yet been in-depth and systematically explored. Here we identified the spatiotemporal pattern of ecosystem services during the past 20 years in Yushu, the eco-fragile region and the centre of Qinghai-Tibet Plateau, as well as clarified its relationships with land use change and human well-being. We revealed that: (1) The structure of the ecosystem and land use in this area have been increasingly stable, and the ecological projects have exerted a positive impact. (2) Although the ecological environmental issues still need more attention, the ecosystem services of the area have been positively developing. (3) Derived by the ecosystem services increase, environmental projects and policies, the human well-beings of culture and education performed much better than other aspects. (4) It is crucial to carry out long-term ecological projects and increase educational investment for maintaining the stability of this ecologically fragile area. This study provides significant support for the regional ecological sustainability decision making, especially for the Qinghai-Tibet Plateau, the roof of the world.
The continuous growth of urban agglomerations in China has increased their complexity as well as vulnerability. In this context, urban resilience is critical for the healthy and sustainable development of urban agglomerations. Focusing on the Beijing-Tianjin-Hebei (BTH) urban agglomeration, this study constructs an urban resilience evaluation system based on four subsystems: economy, society, infrastructure, and ecology. It uses the entropy method to measure the urban resilience of the BTH urban agglomeration from 2000 to 2018. Theil index, standard deviation ellipse, and gray prediction model GM (1,1) methods are used to examine the spatio-temporal evolution and dynamic simulation of urban resilience in this urban agglomeration. Our results show that the comprehensive evaluation index for urban resilience in the BTH urban agglomeration followed a steady upward trend from 2000 to 2018, with an average annual growth rate of 6.72%. There are significant differences in each subsystem’s contribution to urban resilience; overall, economic resilience is the main factor affecting urban resilience, with an average annual growth rate of 8.06%. Spatial differences in urban resilience in the BTH urban agglomeration have decreased from 2000 to 2018, showing the typical characteristic of being greater in the central core area and lower in the surrounding non-core areas. The level of urban resilience in the BTH urban agglomeration is forecast to continue increasing over the next ten years. However, there are still considerable differences between the cities. Policy factors will play a positive role in promoting the resilience level. Based on the evaluation results, corresponding policy recommendations are put forward to provide scientific data support and a theoretical basis for the resilience construction of the BTH urban agglomeration.
Analyzing long term urban growth trends can provide valuable insights into a city’s future growth. This study employs LANDSAT satellite images from 1990, 2000, 2010 and 2019 to perform a spatiotemporal assessment and predict Ahmedabad’s urban growth. Land Use Land Change (LULC) maps developed using the Maximum Likelihood classifier produce four principal classes: Built-up, Vegetation, Water body, and “Others”. In between 1990-2019, the total built-up area expanded by 130%, 132 km2 in 1990 to 305 km2 in 2019. Rapid population growth is the chief contributor towards urban growth as the city added 3.9 km2 of additional built-up area to accommodate every 100,000 new residents. Further, a Multi-Layer Perceptron - Markov Chain model (MLP-MC) predicts Ahmedabad’s urban expansion by 2030. Compared to 2019, the MLP-MC model predicts a 25% and 19% increase in Ahmedabad’s total urban area and population by 2030. Unaltered, these trends shall generate many socio-economic and environmental problems. Thus, future urban development policies must balance further development and environmental damage.
Accurate and rapid evaluation of the regional eco-environment is critical to policy formulation. The remote sensing ecological index (RSEI) model of the Guangxi Beibu Gulf Economic Zone (GBGEZ) during 2001-2020 was established and evaluated using four indices: dryness, wetness, greenness, and heat. This paper proposes an information granulation method for remote sensing based on the RSEI index value that uses granular computing. We found that: (1) From 2001 to 2020, the eco-environmental quality (EEQ) of GBGEZ tended to improve, and the spatial difference tended to expand. The regional spatial distribution of the eco-environment is primarily in the second-level and third-level areas, and the EEQ in the east and west is better than that in the middle. The contribution of greenness, wetness, and dryness to the improvement of EEQ in the study region increased year by year. (2) From 2001 to 2020, the order of the contribution of the EEQ index in the GBGEZ was dryness, wetness, greenness, and heat. (3) The social and economic activities in the study region had a certain inhibitory effect on the improvement of the EEQ.
In tropical regions, mangrove forests are located in the inter-tidal areas between land and sea, and are at risk from both freshwater and seawater floods. Using satellite-derived Normalized Difference Vegetation Index (NDVI) products, this study compared the differences in resistance and resilience of mangrove ecosystems to freshwater and seawater floods in Southeast Asia, and analyzed the spatial characteristics of the stability of mangrove ecosystems under floods in representative areas. Results show that mangroves tended to have lower mean resistance (28.24 vs. 37.32) and higher mean resilience (3.74 vs. 3.56) under freshwater floods, compared to seawater floods. Their resistance increased with the distance from rivers, such that the resistance of coastal areas to freshwater and seawater floods was lower than that of inland areas. These areas with lower resistance showed higher resilience compared to those with higher resistance. Damaged mangroves hardly fully recovered to their normal NDVI levels one year after seawater floods, especially in coastal areas. Although the occurrence of seawater floods was relatively rare in the past, it is likely to increase under more-intense climate extremes in the future, and the threat to the survival of mangroves may also increase. Thus, it is essential to evaluate the stability of mangrove ecosystems under floods.
Traditional trade routes that penetrate the natural barrier of the Himalayas are critical for connecting major Chinese and South Asian markets. Research on these trade routes can contribute significantly to facilitating the construction of the South Asian Corridor and enhancing trans-Himalayan connectivity. Combining historical literature, field surveys, and geographic information system (GIS) techniques, this study examined the spatial distribution characteristics and evolution process of the routes, focusing on transverse valleys of the Himalayan arc. The key findings were as follows. First, there are 21 traditional trade routes traversing the Himalayan region: six Sino-Nepalese routes, four Sino-Bhutanese routes, and eleven Sino-Indian routes. Second, the evolution of traditional trade routes has entailed five distinct phases: an incipient period (pre-7th century), formation (7th century-842 AD), development (842-1959), decline (1959-1962) and recovery (1962-present). Third, the incipient and formative developmental phases were prompted by the spread of Buddhism and the exchange of goods. The stability of local governments in Tibet and Central China and favourable border trade policies along with Britain’s colonial expansion and commercial interests stimulated further development of traditional trade routes. However, India’s strategic miscalculation and “Forward Policy” instigated the decline phase, while the demands of regional cooperation and development are currently the key drivers of the restoration and construction phase. Finally, to shelve disputes, promote cooperation and development, and enhance political mutual trust, governments should recover and construct traditional trade routes by replanning and constructing border trade markets, expanding border trade, developing pilgrimage and tourism, and strengthening cross-border cooperative research under global climate change.
