Compared with the increasingly obvious humanistic tendency in foreign human geography, China's human and economic geography still follows Academician Wu Chuanjun's theory, with human and economic geography as an interdisciplinary subject which is the study of the formation and evolution of the distribution pattern of human activities under the interaction of natural circle and human circle. And China's mainstream school on human and economic geography has been formed with studies on spatio-temporal rule of sustainable development on territories with different space scales, territories with important production and living, and territories with typical geospatial patterns as the main research points. "Territorial System of Human-environment Interaction", developed by Academician Wu Chuanjun, is the important theoretical foundation not only for human and economic geography, but also for the comprehensive research on geography. The essence of the theory, which includes territorial functional, system structured, orderly process for spatio-temporal variation, and the difference and controllability of human-environment interaction system effect, is entirely harmonious with the forefront of thought of the "Future Earth" studies program. In recent decade, with scientific mode of urbanization, major function oriented zoning, road map for the Belt and Road Initiative, Beijing-Tianjin-Hebei urban agglomeration, rural hollowing and targeted poverty alleviation, revitalization of Northeast China and transformation of resource-based cities, and administrative area optimization as the main research objects, theoretical methods have been developed in the aspects of important sustainable process of human and economic geography, territorial function formation and ordering rules for comprehensive geographical pattern, formation and evolution mechanism of urban agglomeration and its resources and environmental effects, sustainable life cycle and the revitalization of the path for problem areas, the interaction between geopolitics, geo-economy and regions, and effect of cultural boundaries on sustainable development. China's human and economic geography has made great progress in discipline development, and the application results have produced profound influences on the ecological civilization construction and sustainable development in recent years. With decades of hard work, China's human and economic geography has reached a world-class advanced level, so as to console the soul and spirit of Wu Chuanjun on the occasion of commemoration of the centenary of his birth.

The optimal control of the human-earth system plays the most important role in the theoretical foundation of human-earth areal system (abbreviated as the "human-earth system") advocated by Academician Wu Chuanjun. Based on the thinking and related discussion of optimal control of human-earth system proposed by Academician Wu, this paper deepened and expanded the theoretical and methodological aspects of structure, nonlinear effects, coupling relationship and evolution of the human-earth system. After that, we focused on the following two aspects. The first is to discuss the optimization of human-earth system and coordinated development of regional PRED (i.e., population, resources, environment, and development), including the relationship between human-earth system optimization and PRED coordinated development, as well as the objectives, key points, theoretical models and quantitative measures of coordinated development of PRED. The second is to explore the path and countermeasures of comprehensive regulation of human-earth system in the new era. First of all, we should promote the continuous and healthy development of human-earth systems through innovation. Secondly, we should optimize the spatial pattern of the human-earth system according to the main function-oriented zoning. Thirdly, we should build a modern economic system through supply-side structural reforms. Fourthly, setting long-term balanced development of population as a goal, we should gradually improve the population policy. Finally, we should follow the market principles to improve the mechanism of paid use of resources and environment and ecological compensation.

The Belt and Road Initiative (BRI) has changed from a China-based initiative to an international consensus, and is becoming a platform for a growing number of countries in the world to explore new international economic governance mechanisms. Such a great change along with impressive achievements of BRI development has attracted academic attention from almost all disciplines except basic sciences, giving rise to huge literature. This paper will first explore data from China Knowledge Resource Integrated Database to summarize the characteristics of literature on BRI in general, and then review progress in research on major BRI topics related to geography. The paper finds: (1) the number of Chinese papers on BRI increased by 21 times in three years, from 1012 in 2014 to 21216 in 2017; (2) these papers cover various BRI-related topics but most of them are macroscopic and very general studies of BRI with a taste of public voices, implying that quality papers with deep academic studies are demanded to support the BRI development; (3) more frequently discussed topics are China's outward foreign direct investment, facilities connection, "going out", globalization, global economic governance, community of shared destiny and internationalization of Renminbi; and (4) specific topics that are more deeply studied by geographers are connotation and discourse of BRI, geopolitical analysis of BRI, China-Europe Express Train, global strategic shipping pivot, model of China's outward foreign direct investment and overseas industrial parks, trade pattern and its impacts on economic growth of both China and its trade partners. Lastly, the paper suggests enhancing the discursive construction of BRI and studies of new BRI mechanisms as well as studies of countries involved in BRI, and promoting dialogues and collaborations between Chinese scholars and foreign scholars on BRI studies.

Cities and villages are components of a specific organism. Only the sustainable development of two parts can support the prosperous development as a whole. According to the theory of man-earth areal system, urban-rural integrated system and rural regional system are the theoretical bases for entirely recognizing and understanding urban-rural relationship. To handle the increasingly severe problems of "rural disease" in rapid urbanization, accelerating rural revitalization in an all-round way is not only a major strategic plan for promoting the urban-rural integration and rural sustainable development, but also a necessary requirement for solving the issues related to agriculture, rural areas, and rural people in the new era and securing a decisive victory in building a moderately prosperous society in all respects. This study explores the basic theories of urban-rural integration and rural revitalization and analyzes the main problems and causes of rural development in the new era, proposing problem-oriented scientific approaches and frontier research fields of urban-rural integration and rural revitalization in China. Results show that the objects of urban-rural integration and rural revitalization is a regional multi-body system, which mainly includes urban-rural integration, rural complex, village-town organism, and housing-industry symbiosis. Rural revitalization focuses on promoting the reconstruction of urban-rural integration system and constructs a multi-level goal system including urban-rural infrastructure networks, zones of rural development, fields of village-town space and poles of rural revitalization. Currently, the rural development is facing the five problems: high-speed non-agricultural transformation of agriculture production factors, over-fast aging and weakening of rural subjects, increasingly hollowing and abandoning of rural construction land, severe fouling of rural soil and water environment and deep pauperization of rural poverty-stricken areas. The countryside is an important basis for the socioeconomic development in China, and the strategies of urban-rural integration and rural revitalization are complementary. The rural revitalization focuses on establishing the institutional mechanism for integrated urban-rural development and constructs the comprehensive development system of rural regional system, which includes transformation, reconstruction and innovation in accordance with the requirements of thriving businesses, pleasant living environments, social etiquette and civility, effective governance, and prosperity. Geographical research on rural revitalization should focus on the complexity and dynamics of rural regional system and explore new schemes, models and scientific approaches for the construction of villages and towns, which are guided by radical cure of "rural disease", implement the strategy of rural revitalization polarization, construct the evaluation index system and planning system of rural revitalization, thus providing advanced theoretical references for realizing the revitalization of China's rural areas in the new era.

Urban agglomeration refers to a highly integrated city and town group. It comes into being with the development of industrialization and urbanization to the advanced stage. The formation and development of urban agglomeration is a long natural process, which is transformed from competition to cooperation. China is in a new stage of urbanization transition, and has entered a new era of leading the global urban agglomeration development in the 21st century. The research and experience model of China's urban agglomeration has been accepted by global urban agglomeration construction as reference. In this paper, the natural law of urban agglomeration is proposed, including developmental gradual law, multi-scale transmission law of space intensive utilization, the combination law of spatial crystal structure, the natural growth of the breeding tree, and the gradient upgrade law of sustainable development. Following these laws, Chinese geographers have made great contributions to the research and development of China's urban agglomerations, which focuses on academic theory, technical method, decision support and planning practice. We developed and scientifically defined the concept of urban agglomeration, and first adopted the identification standard of urban agglomeration space. We established the spatial intensive development and layout simulation decision support technology chain in urban agglomeration, and developed related software chain. We laid out the new pattern of 5+9+6 in the spatial organization of China's urban agglomerations, and formulated the first China's urban agglomeration planning technical regulation. We completed the development plan of most urban agglomerations in China, which has become an important basis for decision-making at the national level. In the future, geographers will play a growing role and shoulder the responsibility in the development of Chinese urban agglomerations. We should combine qualitative and quantitative methods, and use big data and intelligent decision support technology to solve a series of problems in the development of this cause. Only in this way can Chinese geographers make greater contributions to the development of urban agglomerations.

Variations of locational conditions caused by transport infrastructure construction largely promoted the agglomeration of production factors and the local economy and reshaped the regional structure. Hence, measuring transport location has become one of the fundamental topics in geography. Recently, along with transport development, as well as the emergence of new technology, new models, new factors and new industrial forms, the locational conditions have been reconstructed and individual travel concept and patterns changed. The existing research on measuring transport location considers not only the location in the geographic context in terms of the spatial location and transport infrastructure network but also the location in the flow of space concerning the network connectivity, reliability and travel convenience. The research objects changed from various locations to the micro-location regarding group travel characteristics and differences at the individual level. The research contents included door-to-door trips in the accessibility of transport networks. Meanwhile, techniques of big data and GIS-T methods make measuring transport location more accurate.

Resource-based cities refer to the type of cities that exploit and process natural resources, such as minerals and forests in the region. The transformation and sustainable development of resource-based cities is an important part of the research on regional industrial development, regional economy and urban development. Since China started the pilot reform of resource-based cities in Fuxin in 2001, the accurate definition and classification of resource-based cities in China has been one of the focuses of academic discussion. This paper systematically analyzes the historical criteria of the definition and classification of resource-based cities. Based on the previous experiences and using the theory and method of urban function classification, this paper proposes a set of methods to identify resource-based cities. Then, based on the development of resource-based cities and their actual characteristics, this paper tries to establish a comprehensive classification framework for resource-based cities by two kinds of evaluation which are based on resources support ability and sustainable development ability. A total of 262 resource-based cities are divided into 4 types, nemely growth type, maturity type, recession type and regeneration type. The paper also analyzes the different characteristics of different types of cities. This result supports the delineation of the scope and categories of resource-based cities in the "National Sustainable Development Plan for Resource-based Cities" promulgated by the State Council and has become the basis for targeted guidance and policy support.

Administrative division research has become one of the most important parts in human-economic geography, which is closely related with studies on political geography, historical geography, and urban geography. The new argument that administrative division itself can be seen as a resource, which is of great significance to understanding and exerting the effect of administrative divisions in spatial governance and optimization of regional development pattern. Based on the review of the development of administrative division research, three predominant directions should be centered in the future research, that is, optimizing and enhancing regional management efficiency, protecting regional governance security and improving precision management of administrative regions. Starting from the modernization of national governance and governance capacity, the important research direction of administrative divisions was discussed in three points: (1) the optimization of managerial hierarchy and scope of jurisdiction can improve spatial governance efficiency; (2) dividing a large-scale and economically developed province into small part can guarantee spatial governance security; (3) reasonable scope of jurisdiction and establishment of grass-roots administrative divisions can enhance spatial governance precision. Appropriate adjustment of administrative divisions have helped to improve spatial governance, and provided a policy support for building a spatial governance system suitable to China's national conditions.