This paper explored the characteristics of intercity human mobility and the 'negative effects' of massive intercity population movement in China by using mobile internet positioning big data. Two travel periods of Baidu Migration data were selected involving Spring Festival and usual travel time. Based on two mobility indicators, i.e., movement scale and movement scope, the spatial characteristics of intercity population movement were measured by local spatial autocorrelation. With a vital public health emergency, linear regression models were used to measure the differences in the negative effects of the national intercity population movement on different cities and urban agglomerations in China. It is found that three major urban agglomerations, namely, the Yangtze River Delta, the Pearl River Delta, and Beijing-Tianjin-Hebei, are the most significant high-value clustering area of mobility in China. Urban agglomerations and megacities are accompanied by higher risks of negative effects for their super mobility. First, the megacity-centered urban agglomeration will have a more significant negative consequence when it is affected by the negative effects of intercity mobility. Second, the megacity-centered urban agglomeration will significantly spread the negative effects through intercity mobility. It is proposed that the security of urban agglomeration should firstly guarantee the security of mobility. The security of urban agglomerations should be reflected in the resilience of intercity mobility networks. In the process of new urbanization, the development strategy of urban agglomerations needs to focus on the mobility and security of urban agglomerations from the perspective of territory spatial security.
Propagation simulation is an important way to recognize the resilience of network structure from a dynamic perspective. Exploring the relationship between the difference in network structure and the state of network propagation is of great significance to the improvement of network structure resilience and the optimization of territory development space. This paper constructs four typical urban network models: nearest neighbor network, small world network, scale-free network and random network. Using complex network theory and SIS virus propagation model, MATLAB and Gephi are used to simulate infectious diseases, and the four types of networks are analyzed. The variation characteristics of infection quantity and infection time under the difference of network shape, node scale and degree value, and the influence mechanism are discussed. The results showed that: (1) From the perspective of overall characteristics, the difference in network structure affects the strength of network propagation. The heterogeneity value distribution, highly local clustering, and short path length of irregular network will expand the scale of infection and shorten the time of infection. (2) From the perspective of decomposition characteristics, scale is not the core factor affecting network communication. High degree of urban network with power law distribution is the risk of regional and urban suppression of negative transmission. (3) From the perspective of spatio-temporal characteristics, heterogeneous network and regular network have the dual characteristics of robustness and fragility. The advantages of heterogeneous network in peacetime and the advantages of regular network in epidemic time should be fully developed through network switching. Based on this, the resilience optimization strategy of land development space network structure is proposed from the regional and urban levels.
The South China Sea (SCS) is the largest marginal seas in China, and also the area with the most problems in marine territories governance. Due to the fluidity of the sea and the fuzziness of the boundary, marine territory control have many characteristics different from that of the land. Marine territory governance mainly includes islands, sea areas, resource exploration and fisheries management. The territorial control of the SCS is particularly complex and sensitive due to the sovereignty and territorial disputes between China and its neighbors. Firstly, this paper teases out the relevant concepts of maritime territory and summarizes the connotation of maritime territory regulation. Based on the above, this paper discusses the issues related to territorial control and governance of the SCS, and then divides them into two groups, one is resource-ecological dimension, and the other is humanistic-institutional dimension, and the research progress of related issues is discussed in combination with the current dynamics of marine territory governance in the SCS. This paper believes that the future studies of marine territory governance in this water should mainly focus on three aspects, namely, regional development in the SCS, sea relations in the SCS, and the multi-scalar territorial governance in the SCS. This paper will play a positive role in clarifying the research topics of China's marine territory governance and management, and further improving China's marine territory optimization mechanism.
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.