Since the 21st century, China's rural social and economic development and infrastructure construction have attained remarkable achievements, but the imbalance between urban and rural development and inadequate rural development are still prominent. In particular, the living environment closely related to rural life is still the short board of rural development. At the beginning of 2018, the central government issued the three-year action plan for rural living environment improvement (RLEI) to focus on improving the rural living environment, building a beautiful and livable village, and pursuing the Rural Revitalization Strategy. This paper analyzes the concept and connotation of RLEI, explains the mechanism of RLEI promoting rural revitalization, combs the mode and mechanism, effect and evaluation of RLEI, and discusses the key areas of strengthening the research of RLEI. The science of rural living environment has developed rapidly in the past 10 years, and has made remarkable progress in basic theory, evolution mechanism, quality evaluation, regulation and control strategy, especially in the research of basic theory, evolution mechanism and quality evaluation. However, there are still obvious deficiencies in the guidance and support of the current research for practice, and there are still some misunderstandings in the practice of local specific RLEI. Facing the strategic needs of rural revitalization, we need to form "eight consensus" in the understanding and practice of RLEI in the new era. In terms of research, we should strengthen the intersection and integration of rural geography and engineering technology science, urban and rural planning science, management science, sociology, etc., and strive to form a systematic research system integrating theoretical research, technological development, mechanism analysis, effectiveness evaluation, and model optimization, which can better support the improvement of rural living environment and realize the function and value enhancement of rural areas, and then effectively contribute to the Rural Revitalization Strategy.

The world is undergoing tremendous changes, and food security is encountering major challenges in China and even the world. In order to systematically study globalization and explore its new patterns, new issues and new paths for food security, we interviewed ten distinguished professors from different fields and discussed hot topics, including the potential for increasing farmland production, agricultural water and soil resources and food production, food waste, international agricultural product trade, stable supply of key agricultural product, global agricultural food system, dual circulation pattern and corporate actions, global food production and consumption, international food security governance, and cutting-edge research on food safety. The result shows that the global agricultural food system has entered an era of complexity and high risk. International food security governance is facing challenges in terms of resources, binding force and action power. We are facing an increasing pressure of import dependent agricultural products to ensure stable supply. It is necessary to deepen supply-side reform and strengthen demand-side management so as to guarantee national food security. New changes have taken place in globalization. This will test China's ability to deepen agricultural opening-up, participate in global food security governance, and achieve national food security. In the face of complex international and domestic situations, for better national food security governance, it is necessary to adhere to system thinking and coordinate domestic and international markets. It is also very important to target the entire industry chain, emphasize risk control, and handle the relationship between the government and the market. Furthermore, researchers need to explore the internal relationships and specific mechanisms between food security and other important issues, such as food systems, ecosystems, high-quality development goals, agricultural opening-up, and new dual-circulation development patterns. This could provide a scientific reference for establishing and improving the national food security strategy of "featuring self-sufficiency based on domestic grain production, guaranteed food production capacity, moderate imports, and technological support" in the New Era.

The red tourism resources utilization and development of tourist destination have a strong disturbance to human-earth areal system. Based on the resilience evaluation of "ruralism-ecology" system, this study presents a spatial utilization pattern of red tourism resources, which is conducive to promoting the development of red tourism resources and regional sustainable development mutual win-win situation. Taking the Dabie Mountains Old Revolutionary Base Area as an example, we constructed a resilience level evaluation system of the "ruralism-ecology" system of red tourism from four aspects of economy, society, culture and ecology, and identified the spatial characteristics and types of red tourism resources. The results showed that: (1) The resilience of "ruralism-ecology" system in each county was mainly at the middle and low levels, characterised by "high in the middle and low in the surroundings". (2) The resilience of subsystems in the region was barely coordinated, and the coordination of county-level administrative units presented an "olive-shaped" hierarchical structure with more counties at medium level and less counties at high and low levels. (3) The cold spot and hot spot areas of red tourism resources located on the north and south sides of the Dabie Mountains and the central part of the study area, showed a pattern of "large agglomeration, and small dispersion", which were divided into 5 clusters based on their scale and influence. (4) In areas with high concentrations of red tourism resources, the resilience of the "ruralism-ecology" system can be developed to a higher level through the reconstruction of internal elements. In the low- and medium-density areas of red tourism, the resilience of the "ruralism-ecology" system was weak in absorbing and adapting to external disturbances, which inhibited the development of red tourism resources. According to the evaluation results, the spatial pattern of red tourism resources utilization of "three regions, two belts and three cores" can be constructed preliminarily, and differentiated suggestions were put forward from the perspective of "ruralism-ecology" system resilience in different regions. The research results aim to mitigate the interference of the development of red tourism resources to the "ruralism-ecology" system.

Based on the remote sensing monitoring data of land use change/cover in 1990, 2000, 2010 and 2018, using land use transfer matrix, eco-environmental quality index, and ecological contribution ratio of land use transition, this paper analyzes the spatiotemporal features of "Production-Living-Ecological" space structural transformation and eco-environmental effects of land use/cover change in China from 1990 to 2018. On this basis, we identify the main influencing factors of eco-environmental effects and the spatial heterogeneity by using geographically weighted regression model. The results showed that: (1) The production and living space increased, the ecological space decreased, and the overall situation was insufficient from 1990 to 2018 in the whole country. (2) The high-value areas of eco-environmental quality were concentrated to the east of the Hu Huanyong Line during 1990-2018, and mainly in the south and northeast of China. The low-value areas were mainly distributed to the northwest of Hu Huanyong Line. The squeeze of other ecological space and agricultural production space on grassland and woodland ecological space is an important reason for the deterioration of the eco-environment during the study period. (3) Slope, annual precipitation, land use intensity, elevation, topographic relief, population density, and average annual temperature were the main factors influencing eco-environmental quality pattern in China, and the spatial difference of the effect of each factor was obvious. Chinese policies on economic development should take into account the eco-environmental effect of "Production-Living-Ecological" space transformation and influencing factors in the future, and promote the rational distribution of "Production-Living-Ecological" space and the construction of ecological civilization in China.

A better understanding of the connotation of "territory" is a prerequisite for developing the theoretical system and advancing the practical work of spatial planning. It is necessary to constantly update the understanding of "territory" in accordance with the development of disciplines and the changes in the real needs of spatial governance. Therefore, this journal invited 15 young scholars to discuss the connotation of "territory". The main points of view are as follows: (1) Territory is a complex coupled human and natural systems, with the characteristics of pluralism on elements and nesting on spatial and temporal scales. It is necessary to use the thinking of "landscape, forest, field, lake and grass" as a life community to carry out the comprehensive development and utilization and systematic restoration and protection of territory, so that it can become a natural governance platform. (2) Territory is a network space constructed by "flow" and a relational space composed of different stakeholders. It is necessary to integrate the territory through the "space of flows" to promote the sharing of resources and elements between regions to achieve coordinated development; it is also necessary to pay attention to the reconstruction of human and natural relationships and interpersonal relationships, coordinate the interests of multiple subjects, and achieve harmonious development. (3) Territory is a human space. It is necessary to fully perceive the risks, suitability, constraints, and accessibility of the territory. We need compile people-oriented spatial planning to enhance the ecological value, aesthetic value and humanistic care of territory. (4) Territory is the object of spatial planning and governance. It is a specific spatial carrier with marine space, rural space and cultural space, etc. It has attributes such as rights and assets. It is necessary to realize the unified management of resources and assets in the spatial planning, and highlight its economic value, social value and ecological value to achieve the diversified needs of high-quality development and high-quality life for territory.

Food waste and its resulting resources and environmental problems are closely related to global food security, while reducing food waste is gradually considered as Plan B for it. As the main part of food waste at the consumption segment, food waste generated by consumer is the main source of food loss and waste. In this study, the direct weighing method was adopted to obtain first-hand data of food waste of residents in typical areas of China (Beijing, Shanghai, Sichuan, Shandong, Henan and Tibet), and for the first time, the total scale of food waste of residents' consumption and its resource and environmental effects were measured on a national scale. The results show that: (1) In 2018, a total of 34 million tons (67.33 g/d per capita) of food was wasted at the consumer segment in China. Grain waste accounted for the largest proportion (35.44%), followed by vegetables (34.83%) and meat (15.38%). (2) In 2018, food waste occupied 63 million hm² of ecological footprint in China, and the per capita ecological footprint was 448 m². Based on 1.5 hm² of ecological footprint per capita in China, the ecological niche of 42 million people was encroached. Aquatic products (39.28%) and meat (34.22%) accounted for the largest ecological footprint of food waste, amounting to 24.56 million hm² and 21.40 million hm², respectively. The research results are helpful to promote the reduction of food waste at the consumption segment, and have important reference value and significance for alleviating the environmental impact and resource consumption pressure of food waste and improving global food security.

Based on the complex network analysis, this paper constructs the global grain trade network of wheat, rice and corn. The study analyzes the overall characteristics and changing trends of the network pattern, and quantitatively evaluates the influencing factors of the network pattern of global grain trade. The result shows that: Firstly, the global food trade network has become a complex, orderly and interdependent network system. The network scale is increasing, and the degree of connectivity and tightness are strengthening continuously. Secondly, the nodes of the global food trade network show the characteristics of disequilibrium structure. And countries with high strength and high node degree play a leading role in the network, showing the characteristics of network structure dominated by exporting countries. Thirdly, economic and social differences, consistency of trade policies, linguistic and cultural proximity have significant effects on food trade networks. Economic and social differences have driven trade networks to become more interconnected and diversified. Consistency in trade policy contributes to a more sustainable and robust trade network. Therefore, it is suggested that China implement a more diversified and multilateralized grain trade policy. China should strengthen and enhance its centrality among nodes of the global food network, fully integrate into the global food trade network, and promote the building of a global community of shared future for food security.

Water, energy and food are indispensable resources in production and life. They are closely linked and mutually restricted, but their spatial distribution is not harmonious. Affected by climate change, economic and social change, the production and life are restricted. By sorting out the research contents, methods, scales of the WEF Nexus, the comprehensive conceptual framework of WEF Nexus and the transmission and expression of its risk relationship under the influence of changing environment are clarified. In the comprehensive conceptual framework, water, energy and food are regarded as the core of the WEF Nexus, and the influencing factors and potential risks of the water-energy-food system are regarded as the extension of the nexus. This paper points out that the definition of WEF Nexus has not been unified, and "connectionism" and "methodology" are two common explanations. The existing studies have assessed the status of the WEF Nexus, quantified the consumption relationship between resources and simulated it under different economic, social and climate scenarios. Status assessment includes safety, pressure, efficiency, resilience, and sustainability. There are some problems in the current research of WEF Nexus. Data missing and inconsistency hinder the calculation. Only one or several factors are considered in the application of the model, which can not fully describe the complexity of the system. Dynamic feedback research is limited by data and quantitative methods. Existing research is difficult to really apply to policy control. Therefore, monitoring, collection and integration of data, exploration of standardization model and establishment of multi-factor integration tool, system risk assessment and dynamic adjustment, resilience improvement, urban scale research and smart management are all the focus of attention in the development of the WEF Nexus.

"Three rural issues" (issues concerning agriculture, rural areas, and farmers) is an important mainline of the CPC's centennial course of party building and China's urban-rural development. In order to solve the "three rural issues" in the New Era and promote the implementation of rural revitalization strategy, we hereby invite ten experts in the research field of "three rural issues" and rural revitalization research to conduct interviews. The interview mainly focuses on three perspectives: Historical process and institutional context, urban-rural system and cross scale space, and the integration of policy theory, technical methods, and rural construction practice. It revolves three main lines: The strategic stage and institutional changes of "three rural issues", the essence of "three rural issues" and the ways to solve new "three rural issues", and the rural revitalization mechanism and rural construction practice. The main conclusions are as follows: (1) The essence, key areas, and institutional mechanism innovation of the "three rural issues" in the context of spatio-temporal processes and institutional contexts. It is necessary to grasp the laws of "three rural" (agriculture, rural areas, and farmers) and diagnose the "three rural issues" from the perspective of urban and rural regional systems and even the global perspective space. The "three rural issues" is an optimization decision-making problem for improving the functions of rural regional systems within the overall framework of urban and rural regional systems. The imbalance in urban-rural development and insufficient rural development are the concentrated reflection of the "three rural issues" in the New Era. The crux of the "three rural issues" lies in the uncoordinated development of "human, land, and industry". The core goal of China's "three rural issues" in the new development stage is to move towards the common prosperity of farmers and rural areas. The corresponding development system and working mechanism of "agriculture, rural areas, and farmers" need to grasp the two "bottom lines", do a good job in the two "connections", and promote the two "integrations" in key areas such as national food security, farmers' livelihood development, modern agriculture and rural development, rural revitalization, and urban-rural integration development. (2) The theory of rural revitalization and the rural spatial planning under the requirements of urban-rural system interaction and people's common prosperity. The research and solution of China's "three rural issues" are rooted in the geographical theory of territorial system theory of human-environment interaction and location theory, the sector economy theory and the economic cycle theory, as well as the theory of development economics, sociological function theory and social conflict theories. In the research practice of the "three rural issues", land use transformation theory, rural reconstruction theory, rural development multi-body and multi-pole theory, interface theory, rural attraction theory, and rural sustainability have also been developed. The urban-rural integrated development and the common prosperity of the people should be the result of balanced regional development and Chinese path to modernization. The folk expression of "making rural life attractive" and the strategic goal of "basically realizing rural modernization by 2035" are mutually "exterior-interior" relationship, which can be comprehensively explained from the following three aspects: The spatio-temporal differences and path differentiation of rural settlement evolution and multi-functional transformation, and the phenomenon explanation of rural gentrification and the theoretical application of rural attraction in the context of urban-rural interaction, as well as the theoretical significance and practical path of rural modernization under the guidance of rural sustainability science. Improving local quality is an inherent requirement to meet the people's needs for a better life, and it is an essential requirement and general law of rural revitalization driven by innovation. As the edge of the national urban-rural system, rural areas face constraints such as segmentation, remoteness, low density, and insufficient heterogeneity dividends in improving local quality. Therefore, to improve local quality of rural areas, it is necessary to adapt to and alleviate the relative inefficiency of rural geography, and its important promotion paths include the characteristic development based on endowment, digital transformation and rural agglomeration centered around cities and towns. Guided by spatial planning and taking into account the integrated functional development of production-living-ecological spaces in rural areas, as well as the integration of urban and rural space through spatial planning, through promoting the quality of living space through comprehensive land improvement, assisting in the realization of multifunctional value in agricultural space through refined management, ensuring the sustainable use of ecological space through systematic protection and restoration, which is a solid foundation for rural revitalization and the construction of a new urban-rural relationship. (3) The path mechanism and technical support for the comprehensive rural revitalization and rural construction under the new needs of ecological civilization construction and governance modernization. Comprehensive rural revitalization requires the revitalization of industries, the reform of land, the development of human well-being, and the intelligent updating of technology. First, the essence of operating rural areas is the rational allocation of resources as the object of factors. It is necessary to integrate the high-quality development of agriculture with the high-quality and livable rural areas, promote the interaction and integration of urban and rural systems, actively link natural science, engineering technology innovation, and institutional innovation from the perspective of the big food concept, and implement food safety and important agricultural product supply security. Second, facing the new demand of rural sustainable development and governance modernization, we should innovate the property right governance integration mechanism of rural land system, especially actively build a rural green development mechanism with farmers' participation and an external benefit sharing mechanism of ecological environment governance. Third, it is urgent to break through the barriers that farmers share the gains from the appreciation of rural assets, fill the gap between small farmers and modern agriculture, and establish a concept of county governance that meets the needs of Chinese path to modernization. Fourth, rural construction is an organic combination of the governance of public spaces by the state and the daily life practices of farmers. Through the theory and technology of "computational" rural areas, effective connection and information sharing between the state and rural areas can be achieved, promoting coordinated development from micro to macro, and from local to whole. And we should achieve the aim of building livable, suitable for work, and beautiful rural areas, through multi-level main body co-construction, co-governance, and management. To sum up, the interview views can provide theoretical reference and decision-making reference for the "three rural issues" work innovation and rural revitalization practice towards Chinese path to modernization.

The establishment of the nature protected area system based on national parks is seen as the important implementation of Xi Jinping's Thought on ecological civilization from the perspective of reform. From the perspective of homeland space governance, it is the core carrier of ecological construction and the primary position of maintaining its primary position in national ecological security. In order to achieve harmonious coexistence between man and nature in the nature protected area, it is necessary to achieve "the strictest protection" and "lucid waters and lush mountains are invaluable assets", which is both ecological and civilized. In order to better understand and interpret the development of China's protected areas and the driving factors behind them in the context of ecological civilization construction, we invited seven well-known experts from ecological civilization and national park related fields to discuss the following aspects of the protected areas: ecological civilization construction, human-land relations, conflict and symbiotic transformation mechanism between man and nature, the governance system of the protected areas and the contribution of Chinese governance system to the construction of global ecological civilization, natural resource asset property rights system, daily management and supervision of the protected areas, ecological compensation and concession of the protected areas, and etc.

The main conclusions are: (1) Only through establishing the ecological civilization system can local governments deal with the relationship between the protection and development of the protected areas, and the establishment of the national park system has made the fastest overall progress and is the most systematic part in the reform of the ecological civilization system. (2) To achieve the "strictest protection", the development of the protected areas is inseparable from the support of the concept of the human-land relations. It stresses on the importance of paying attention to the "land" of the nature protected area, as well as emphasize the significance of the functions and participation of people from the perspectives of "adapting measures to local conditions" and "authenticity of land lovers". (3) The institutional causes of human-nature conflict in the nature protected area mainly stem from the conflict of interests and structures between governments at different levels. (4) To resolve conflicts and achieve symbiosis between man and nature, it is necessary to optimize the governance system, especially adjust the responsibility and rights system of governments at all levels. Moreover, in order to achieve the goals of "ecological protection first" and "public welfare for all people", we should reconstruct the dimension of interests, and form a community of common interests. (5) It is necessary to coordinate and efficiently allocate the responsibilities and rights of different stakeholders under the unified management goals, and construct a co-governance pattern and pluralistic co-governance system of the nature protected area so as to handle various relationships of multiple subjects in the governance system of the nature protected area. (6) There are deep-seated contradictions between the logic of capital and ecology, between the protected areas and human settlements systems, between nature conservation goals and global execution. The institutional advantages of socialism with Chinese characteristics in the new era and the cultural tradition of "man and heaven" formed by thousands of years of accumulation can contribute Chinese wisdom to the construction of global ecological civilization. (7) In view of the construction needs of the protected areas system and its positioning in the spatial planning, it is necessary to optimize the property rights system of natural resource assets, and explore the control system of the territorial space that is conducive to handling the relationship between protection and development. Before the reform of the national institutions, there was a problem of fragmented management ("Nine-Dragon Water Governing" in Chinese) in the protected areas. The daily comprehensive management and supervision and law enforcement of the protected areas have been carried out to realize the unification, standardization and orderliness of management and supervision after the institutional reform. (8) In order to achieve ecological protection goals, it is necessary to universally realize the transformation of "two mountain theory", especially under the market economy. The national concession system can be seen as a market-oriented and diversified ecological compensation path and an effective way of green development, which requires the exploration of governmental franchise and brand franchising in active and diverse means.

To develop the marine economy and build a strong marine country, we need to care about, understand and manage the ocean from the perspective of national strategy. In order to systematically understand China's marine resource economy and strategy under the background of marine ecological civilization construction, nine well-known experts from marine-related fields were invited to discuss marine ecological civilization construction, marine land space planning, marine ecological pasture construction, and coastal ecological restoration. They conducted exchanges and interviews in frontier research fields such as marine strategic emerging industries, marine science and technology development, deep-sea mineral resources development, marine geopolitics, and China's participation in global ocean governance. According to their interviews: (1) The construction of marine ecological civilization is an important part of the construction of a powerful marine country. In the construction of marine ecological civilization, we should clarify the goal of building a beautiful ocean, master the methods of marine ecosystems, adhere to the major strategy of coordinating land and sea, and build an institutional system for marine ecological civilization. (2) National marine space planning should integrate existing sea-related plans, rationally develop, utilize and protect marine resources, innovate planning technologies and planning governance concepts, and strengthen marine space control indicators, marine space development capabilities, and local characteristic mechanisms for marine space governance, etc. (3) The construction of marine ranches should focus on the industrial chain and promote the construction of "all-for-one" marine ranches; strengthen the original drive, build an "all-for-all" marine ranch technology system; advocate integrated development and cultivate new "all-for-one" marine ranches. (4) Coastal ecological restoration based on "natural restoration" emphasizes the use of technologies to optimize the spatial layout and resource management of land-ocean staggered areas, fully consider the process and mechanism of natural restoration of coastal ecosystems, and improve the efficiency of ecological restoration. (5) The development of marine strategic emerging industries should grasp the general trend of the digital economy, focus on the development of intelligent manufacturing, accelerate the upgrading of the industrial structure, adhere to green and low-carbon development, and actively connect with regional strategies. (6) The key tasks for the future development of marine science and technology are to focus on the new strategic fields of deep sea and polar regions, improve the real-time fine observation and forecasting capabilities of key sea areas, focus on the intensive use of marine resources and energy, and strengthen the research and development of key core technologies of marine engineering equipment. (7) In the development of deep-sea mineral resources, it is necessary to strengthen international cooperation, carry out multidisciplinary investigation, long-term monitoring, enhance the research and development level of deep-sea development technology, evaluate the environmental impact of deep-sea mining, reduce the disturbance of the deep-sea development process to the marine environment, and realize deep-sea mining and deep-sea environmental protection coordinated development. (8) China should implement a spatially differentiated and targeted marine geostrategy to serve the unification of the motherland, the maintenance of marine rights and interests and the utilization of marine resources, and the safety of marine transportation and ecological environment, so as to ultimately serve the construction of a community with a shared future for the ocean. (9) We should implement the "going out" strategy of China's marine spatial planning technology, actively promote the strategy of building a "node network system" in China's overseas parks, and implement the talent training and training strategy for the needs of the Belt and Road Initiative, in order to provide necessary space fulcrum and technical support for global marine governance.

Cultivated land abandonment has a profound impact on China's food security. Taking the main grain producing areas in China as an example and based on the identification of the distribution of abandoned land, this paper measured the spatial distribution pattern of abandoned land, established the mediating effect model of cultivated land abandonment, and explored the influence mechanism of cultivated land abandonment on regional grain yield. The results showed that: (1) The area of abandoned cultivated land in the main grain producing areas of China was 4.0553 million hectares, with a rate of 5.85%; the distribution of abandoned land presented a T-shaped pattern, mainly concentrated in the Northeastern Heilongjiang, Northwestern Jilin and Southern Inner Mongolia. (2) Cultivated land abandonment had a significant negative impact on the grain yield of the main grain producing areas. In 2017, these areas lost a farmland production potential of 13.3915 million tons, and the loss of grain output was as high as 22.656 million tons, accounting for 4.69%; Inner Mongolia was the most affected region. (3) Grain sown area, farmland production potential, and agricultural technology input all played an intermediary role, and their regression coefficients were -0.194, -0.025 and 0.006, respectively. (4) We should follow the trend of urban-rural integration and agricultural-rural development, strengthen the input of modern agricultural production factors and policy support in major grain producing areas, and construct the flexible mechanism of spatial transformation between grain production and cultivated land fallow to ensure food security in China.

Evaluation of biodiversity maintenance function is an essential precondition for ecosystem assessment. In this study, we modified and improved the biodiversity maintenance service capability model based on the law of species richness vertical zonality. Then, we further quantified the responses among three spatial scales of provincial, municipal and priority zones. The main conclusions in this study are as follows: (1) There are significant distribution differences in the scales of provincial, municipal and priority areas of biodiversity conservation (PABC). The most important areas in the provincial scale are concentrated in the Qinling-Daba mountains, while they are scarcely distributed at the municipal scale. There is a high consistency of distribution between nature reserves and the most important areas at the priority area scale. (2) The accuracy of identification from high to low in the three scales was: the priority area scale (19.5%), provincial scale (11.7%), and municipal scale (11.2%). The priority area scale assessment is more accurate than that of the administrative area scale. (3) The most important area identified by the scale assessment of the priority area is 28032.3 km², accounting for 13.7% of Shaanxi province. Comprehensive evaluation results of land use structure and species importance in extremely important areas are superior to those in the administrative area scale.

The symbiotic development of red tourism resources and other types of tourism resources is an inevitable phenomenon of market allocation of resources, so the research is of great significance. Taking the tourism resources of Hunan province as objects and the scenic spots as symbiosis units, we identified scenic spots into five types of red-dominated, green-dominated, blue-dominated, patina-dominated, and entertainment-education-dominated through the type structure of tourist resources. Calculating the symbiosis potential energy based on the scenic spots' quality index and the convenience index between them, and using Ucinet and ArcGIS software analysis based on social network theory, we found that there are five levels of symbiosis potential energy in tourism resources of Hunan, which express properties of the primary contact center of pure altruism, the secondary contact center of altruism, the important contact point of symmetrical mutual benefit, the general contact point of asymmetric mutual benefit, and the loose contact point of pure egoistic, while red tourism resources showed an absolute advantage in symbiosis potential energy. Red tourism resources play a significant organizational role in the tourism resource symbiosis system, which is composed of five symbiosis communities. Among them, one community, with the advantage of Changsha-Zhuzhou-Xiangtan (CZT) red tourism resources, has the closest internal connection and the best symbiosis potential energy, while the internal connection in the other four symbiosis communities decreases in the order of the first one co-constructed by tourism resources of patina, red and blue in southern Hunan, the second one co-constructed by tourism resources of green and patina in western Hunan, the third one with green-advantaged tourism resources in southwestern Hunan and the last one with patina-advantaged tourism resources in the area around Dongting Lake. The symbiosis community with the advantage of red tourism resources in CZT has connections with all the other four symbiosis communities, and it has a closer contact with the one which is co-constructed by tourism resources of patina, red and blue in southern Hunan. There is a closer relationship between the symbiosis community co-constructed by patina, red and blue tourism resources in southern Hunan and the symbiosis community with green-advantaged tourism resources in southwestern Hunan. Red tourism resources are the main body of the core area of the tourism resources symbiosis system in Hunan. Among 53 scenic spots in the core area, 18 are red-dominated scenic spots, accounting for 33.96%; 27 belong to the symbiosis community with the advantage of red tourism resources in CZT, accounting for 50.9%. The research results show that red tourism resources perform strong support and synergy for the development of Hunan's tourism industry, and reflect the unique value of promoting regional high-quality development.

In this paper, the spatial center of gravity model and spatial mismatch index method was applied to systematically analyze the spatio-temporal pattern, spatial mismatch characteristics, and influencing factors of global population and food in 1990-2017. The results showed that: (1) In the past 30 years, the global population and food has showed a growth trend, but their change characteristics are obviously different in temporal distribution. The per capita food production has obvious spatial differences in the world, and the contradiction between population and food in most countries is serious. (2) On the global scale, there is an obvious spatial mismatch between the center of gravity of population and food, which shows a trend of reverse mismatch in spatial distribution. (3) On the national scale, the regional difference of spatial mismatch between population and food is obvious, showing a spatial pattern of "positive mismatch area - negative mismatch area - positive mismatch area" from south to north. Negative high mismatch regions are stable in countries such as India and Japan, and positive high mismatch regions are stable in countries such as the United States and Canada. (4) The spatial mismatch pattern of population and food on all continents is basically stable, and the countries whose spatial mismatch index changes direction are distributed in Asia, Europe, South America and Africa. (5) The combined effect of natural environment, international environment, agricultural development and social factors has obvious regional differences in the spatial distribution of population and food, thus forming a spatial mismatch pattern between global population and food. It is necessary to accelerate the structural reform of agricultural supply side, enhance agricultural competitiveness and food self-sufficiency rate, reasonably allocate and deal with both domestic and international markets and resources, construct countermeasures to avoid fluctuations and uncertainties in world grain trade, and build a guarantee system for China's agricultural ecological security and food security.

Under the goal of common prosperity, how to achieve innovative rural development by utilizing rural tourism resources is an important topic of rural research in the new era. Eight scholars from the fields of geography, tourism, management, and other fields discussed the innovative development of rural tourism and the realization of common prosperity goals from different perspectives, including resources, participants, and mechanisms. Specifically: in terms of resource utilization, it is necessary to attach importance to the inheritance and utilization of rural intangible cultural heritage and empower the development of rural tourism resources with art, at the same time, solve rural problems through the development of digital economy. As for participation subjects, we should emphasize the importance of enterprises, and continue to improve the distribution mechanism between the enterprise and the rural community. In the innovative utilization of rural tourism resources, we should build a mechanism system related to both rural industry development and residents' well-being and pay more attention to the spatial value of rural tourism resources. On this basis, rural areas should continue to promote a new development model including tourism development, rural revitalization, urban-rural integration and common prosperity.

Based on statistical core journals and core scholars, this paper uses softwares such as CITESPACE, ORIGN, and Data-Driven Documents, to review the development of research, sort out hotspots and put forward research prospects on resource and environmental carrying capacity (RECC) assessment in China in the past 35 years. The results show that: (1) The evaluation of RECC in China follows the trajectory of "single factor", "multi-factor" and "dynamic integration", and the applied research evolved from "population capacity", "unilateral problem of regional development (RD)", to "multifaceted problem of RD". (2) According to the logic of "scientific evaluation - mechanism disclosure - practical application", this paper points out that, scholars mainly used the index system method, comprehensive evaluation method, footprint method and other methods to estimate the bearing capacity. Based on the calculation results, scholars summarized the spatial and temporal distribution of carrying capacity, identified the impact factors, and revealed the mechanism, to play a supporting role of carrying capacity in promoting regional economic development, speeding up new urbanization, optimizing territorial space, monitoring, early warning, simulation and prediction. (3) Based on the above, it is suggested that the following four aspects should be further optimized, namely, interdisciplinary research, specificity and advancement of evaluation indicators, depth of mechanism disclosure, and dynamics of carrying capacity evaluation.

The socio-economic sphere is an indispensable part of Planetary Boundary (PB) sustainability evaluation system. In this context, this article makes a comprehensive review of theoretical and empirical literature regarding the existing socio-economic sphere. First, an evaluation has been made for a total of 15 socio-economic sphere dimensions proposed by the "Doughnut Theory". Second, based on the different types of research samples in terms of industrial, national, and cross-country aspects, we illustrated and analyzed one or more specific indicators corresponding to each dimension. Finally, we summarize the indicator threshold setting methods, including the continuation of conventions, the reference of experiences and the reference of typical samples. On the basis of summarizing and evaluating previous research results, this article takes 30 provinces, autonomous regions, and municipalities in China as samples for the first time, using statistical yearbooks and the Chinese General Social Survey (CGSS) data to compare the corresponding indicators in the "Twelfth Five-Year Plan" (2011-2015) official document as the threshold, so that the sustainability status of China's socio-economic sphere under the PB framework has been evaluated. The results show that China has reached the optimal state in terms of income level and job opportunities, and the poverty problem has been partially alleviated, but the performance of water resources and energy consumption is not good. In terms of the improvement of sustainability level, Southern China shows a trend of "from west to east", while Northern China presents a trend of "from north to south". The socio-economic sphere needs to be further improved in terms of content enrichment, theoretical deepening, and objective setting of thresholds.