Geographic science is a discipline that studies the spatial patterns and temporal evolution of the human living environment and human-environment interactions on the Earth’s surface system (Fu, 2017; Chen et al., 2019). According to Xuesen Qian, geographic science is parallel to the natural sciences and social sciences while also acting as a bridge that links the two (Qian, 1991). Scientific modern geography was underdeveloped in China until geography was introduced in the 1930s from Western countries, although geography has a long history in China. Now, geography has transformed from traditional qualitative descriptions and daily knowledge to geographic science. From the perspective of its development in China, geographic science is one of the origins of Earth science. Many other disciplines in Earth science were initially considered to be internal branches of geographic science. As they developed, these branches eventually formed new disciplines and became independent from geographic science. Within geographic science, as the impacts of human activities and climate change on the Earth’s surface system have increased, natural and human factors and the complex nature-socioeconomic system have undergone drastic changes. With the emergence of revolutionary technologies and new research fields such as remote sensing science, geographic information science, space and social theory, and global change science, the theories and methods of integrated research in geographic science have continuously expanded and deepened, forming numerous and complicated new disciplinary branches (NASEM, 2019).

The two branches of physical geography and human geography can no longer fully cover the latest developments in geographic science (Xiong et al., 2020). On the one hand, many new disciplines have been derived from physical geography and human geography. For example, the cross-field integration of physical geography with archaeology and anthropology has led to the formation of emerging disciplines and research directions such as human living environment studies (Chen et al., 2020). In addition, the expansion of the spatial concept in geographic science has given birth to planetary geography, and the focus on the cryosphere has prompted the establishment of the disciplinary structure of cryospheric science (Qin et al., 2018). These emerging disciplines must be systematically reviewed and categorized so that they can be accurately positioned. On the other hand, the cross-field integration of geographic science with information science has led to the rise of information geography, which has revolutionized and expanded the scope of research in geographic science and led to the emergence of various fields such as geographic remote sensing science, geographic information science, and geographic data science. In addition, the orientation of integrated geography must be re-examined, and the relationship of traditional disciplines such as regional geography and historical geography to integrated geography must be determined. In short, the current disciplinary structure of geographic science needs to be further developed to better reflect the latest developments of geographic science (Cai, 2019).

In planning the disciplinary structure of geographic science in the “Development Strategy of Discipline and Frontier Research in China (2021‒2035)”, we review and refine the disciplinary structure of geographic science. The main principles include (1) combining the strategic needs of national development with the development trends and current situation of geographic science and taking into account the existing disciplinary structure of geographic science while covering the latest research progress in the field; (2) proposing information geography as a secondary discipline of geographic science, alongside physical geography and human geography; and (3) emphasizing the importance of integrated geography and highlighting the characteristics of geographic science as a comprehensive and interdisciplinary discipline. Additionally, with a focus on the relationship between humans and nature, the regionality of geography (from local to global scales) attempts to understand regional spatial processes by integrating the processes of physical geography and human geography through new means of information geography, giving rise to secondary discipline-integrated geography. Here, we introduce the new disciplinary structure of geographic science to peers in the geographic science community in a series of articles. This paper is an overall introduction to the disciplinary structure of geographic science, while the other three papers introduce the disciplinary structure and development strategy of physical geography, human geography, and information geography.

Geographic science consists of four major branches: integrated geography, physical geography, human geography, and information geography (Figure 1).

Integrated geography is the fulcrum of all other branches of geographic science. Geographic science is a discipline that studies the Earth’s surface system. Regional characteristics inevitably require a comprehensive synthesis for specific regions, which is undoubtedly the basis for the existence of geographic science, its most prominent feature, and its greatest difficulty. The integrated study of the geographic environment can yield dialectical understandings of its formation and development (Huang, 1960). Within integrated geography, theoretical geography should be reconstructed to provide a systematic methodology and theoretical fulcrum for the holistic development of geographic science. Integrated geography should also include applied geography, which is guided by the methods and theories of geographic science to solve practical problems that are closely related to nature and socioeconomic development. Regional geography is a traditional discipline of geographic science and serves various geographic divisions and regional planning purposes based on regional geographic investigations. In the new era, however, regional geography should focus on sustainable development needs at different spatial scales. It should also adapt to the new pattern of global development and the new stage of China’s growth given the ever-changing developments of human civilization. Historical geography focuses on changes in the geographic environment over time. Documented materials from China’s long and rich history are used to study the human-nature relationship and its regional differences during historical periods.

Physical geography is not only the basic discipline of geographic science but also the link between geographic science and other Earth science disciplines (Fu, 2018; Chen et al., 2019). Physical geography has traditionally been divided into integrated physical geography, which studies landscapes, land, and other physical geographic complexes, and sectoral physical geography. In recent years, studies of specific geographic units (e.g., deserts, lakes, and wetlands) and special physical geographic elements (e.g., glaciers, permafrost, and other elements), as well as multiple or total elements of watershed systems and even the entire Earth surface system, have been conducted (Cheng and Li, 2015). Sectoral physical geography focuses on single physical geographic elements, such as the climate, landforms, and vegetation. With a focus on interactions between humans and the environment in the past, human living environment science studies prehistoric human diffusion, social developments, and the evolution of civilization and constitutes a new cross-field at the intersection of physical geography, archaeology, and anthropology (Chen et al., 2020).

Human geography, which concentrates on the human-nature relationship and takes the regional and spatial distribution law of human activities as the research object (Wu, 1991; Fan, 2019), consists of various major branches, such as integrated human geography, economic geography, urban geography, rural geography, and social-cultural and political geography. Of these, integrated human geography is focused on the coupling processes of the human-nature system and geographic patterns for sustainability and is mainly tasked with the integrated study of the spatial processes and patterns of human activities. Economic geography focuses on industrial economic activities and interprets regional development patterns by comprehensively employing the theoretical methods of economics, social science, and quantitative analysis, in combination with the integrated perspective and spatio-temporal differentiations of geography (Fan, 2012; Lu, 2017). Urban geography and rural geography mainly study populations and living spaces, with the aim of contributing to the planning and development of China’s urban system by addressing the pressing and difficult issues in the urbanization process. Sociocultural and political geography takes nonmaterial human activities as the main research object and is a general term for social geography, cultural geography, and political geography, which are emerging research directions within human geography.

Information geography, which has become a distinct and indispensable part of geographic science, mainly includes geographic remote sensing science, geographic information science, and geographic data science. Among these, geographic remote sensing science results from the deep integration of remote sensing and geographic science. Based on the basic theories of remote sensing, such as radiative transfer and quantitative inversion, geographic remote sensing science has led to various application branches, such as remote sensing applications of vegetation, hydrology, and the cryosphere. Geographic information science aims to develop methods of cognition, expression, analysis, simulation, prediction, and optimization for geographic spaces based on information technologies and to explore the expression and coupling methods of natural geospatial spaces and human and social spaces in the geographic information space. This field mainly focuses on resolving fundamental problems in the implementation and application of geographic information systems. Geographic data science develops methods of big Earth data mining and analysis, and geoscience intelligent computing relies on rapidly developing technologies such as big data and artificial intelligence. The aims are to achieve the grand integration of observations, data, and models and to facilitate the transformation of geographic data and information in knowledge development and decision-making, thereby solving the problems arising from the proliferation of geographic data and the limitations of geographic knowledge.

Given international and domestic circumstances, the development of geographic science continues to face new problems, challenges, and opportunities. Taking the opportunity to plan the disciplinary structure of geographic science in the “Development Strategy of Discipline and Frontier Research in China (2021‒2035)”, this article systematically introduces the disciplinary structure of geographic science, which reflects new developments and accounts for the existing disciplinary structure of the field. We hope that this new disciplinary structure will continue to improve the branches of geographic science, promote the development of emerging disciplines under the framework of geographic science, and prompt thinking and innovations regarding the development direction of the field.