1. Introduction
The 21st-Century Maritime Silk Road has gradually attracted the attention of researchers since China adopted the “Belt and Road Initiative”, where Belt is short for the “Silk Road Economic Belt”, and Road refers to the “21st-Century Maritime Silk Road”. The “Belt and Road Initiative” is a global sustainable developmental strategy initiated by China and represents innovation in the model of world economic governance and international regional cooperation [
1]. Since the issuance of the Vision and Action to Promote the Construction of Silk Road Economic Belt and 21st Century Maritime Silk Road [
2] (hereafter referred to as the Vision and Action) by China in March 2015, the Belt and Road has rapidly become a research hotspot. Therefore, researchers have begun to focus on the connotation of the “Belt and Road” construction, the impact of opening up policies, infrastructure cooperation, international trade, and investment cooperation [
3,
4,
5,
6,
7], but there has been a lack of discussion on the regional impact of cities. According to the evolution pattern of the ancient Silk Road, the Maritime Silk Road is generally divided into three major routes, namely the east route, the south route, and the west route [
8], as shown in
Figure 1. The south and west routes start from the South China Sea and extend to Southeast Asia, South Asia, West Asia, East Africa, and European countries. Some scholars have noted that as the Belt and Road stretches thousands of kilometers, a few geographic pivots are needed to perform the functions of connecting, linking, and radiating out to surrounding spaces for the efficient construction and smooth operation of the Belt and Road [
9]. Therefore, the South China Sea and its surrounding areas are planned as the strategic basis of the Maritime Silk Road due to their important geostrategic position [
10]. Southeast Asian countries, as the closest part within the spatial range of the 21st-Century Maritime Silk Road to China, are the most important foothold for the construction of the 21st-Century Maritime Silk Road beyond the Chinese border. Fujian Province and Southeast Asian countries have interlinked geography, close folks, and kindred cultures. As the gateway into both the south route and west route of the 21st-Century Maritime Silk Road, the province is an incomparably important location on the 21st-Century Maritime Silk Road that faces the South China Sea and the whole world. Meanwhile, the province, as the starting point of the historical Maritime Silk Road, has continued its pivotal role in different ways and forms for a millennium. In addition, the Vision and Action advocated for the construction of a core area of the 21st-Century Maritime Silk Road in Fujian Province [
2]. Therefore, promoting the construction of a core area of the 21st-Century Maritime Silk Road in Fujian Province, and studying the effects on regional sustainable development is of vital importance for the further establishment of gateways from the South China Sea into the surrounding Southeast Asian countries for cooperation, which would have good effects on China to deepen geostrategic cooperation with Southeast Asian countries and to ensure more sustainable and balanced regional development. However, few existing studies have quantitatively measured the regional influence of Fujian Province on the 21st-Century Maritime Silk Road, and further research on the centrality and connectivity of Fujian Province in the region is required.
In the context of globalization, cities are no longer isolated as they interact more closely with cities and regions beyond national boundaries [
11,
12]. Globalization has given rise to the theory of space of flows [
13] and has promoted research on world city networks [
14]. City networks focus on inter-city relationships and underscore inter-city connections and cooperation [
15]. According to a literature review, existing studies on city networks both in China and in other countries are centered on population, economy, transportation, information, and innovation [
16,
17,
18,
19] and characterize urban connections through empirical paths such as transportation infrastructure networks, business organizations and connections, economic connections, and innovation cooperation, in order to reveal the levels of cities and the features of association networks in the region [
20,
21,
22]. Taylor and some other scholars proposed a theory and method of characterizing the urban network by using the internal connections of advanced producer services enterprises, which has been widely recognized by scholars [
23]. They pointed out that enterprises are the “actors” that drive the flow of factors in city networks and that the spatial layout of enterprises and inter-enterprise connection networks are important research perspectives of city networks [
24]. City network research based on the perspective of enterprise networks is now the hot spot and frontier of urban geography research [
25]. To date, studies on city networks based on enterprise connections are mainly focused on whole industries and relatively mature industries as the sample of research [
26,
27,
28]. City networks based on emerging industries (such as information-related industries and technology hardware and equipment industries) are still relatively rare. Some scholars have studied the network among strategic emerging industries, such as the photovoltaic industry [
29,
30]. Some scholars have analyzed the corporate networks in manufacturing subsectors, including in the technology hardware and equipment subsectors [
31,
32]. Additionally, there is room to develop research on the features of city networks from the perspective of emerging industries. Therefore, this study selects information-related industries as representatives of emerging industries to explore the new patterns of regional city networks in the context of the development of information-related industries.
Since the 1990s, the rapid development of digital technology and computer networking has brought the global economy into a new information age [
33,
34], in which the new manufacturing sector represented by informatization and artificial intelligence and emerging industries such as e-commerce and other similar platforms have become important directions for the future economic development of cities. According to the Provisional Regulations on Statistical Classification of Information-related Industries issued by the National Bureau of Statistics of China, information-related industries mainly refer to the collection of various activities associated with electronic information. These industries, as part of the emerging sectors in the new information age, have gradually become a crucial means for cities to optimize the industrial structure and to promote competitiveness. The research focus of city networks varies at different times. Compared with traditional producer services, information-related industries are becoming the main driving forces to reshape regional spatial patterns due to the better role that they play in guiding the direction of the future economic development of cities. The strategic and emerging nature of these industries, coupled with other characteristics such as the high liquidity of the market structure, will continuously affect the levels of cities and the evolution of the functional structure in regional networks, thus resulting in the reshaping of the city networks [
35]. Therefore, the construction of a firm interlocking network of information-related industries at a regional scale and the analysis and identification of the hierarchical structure and regional connections of Fujian Province in the network can, to a large extent, provide a reference for the analysis of the potential of Fujian Province’s nodal cities on the 21st-Century Maritime Silk Road in regional competition.
Based on the above analysis, a firm interlocking network covering 31 cities (including nodal cities along the southeastern coast of China and cities in Southeast Asian countries) on the south route of the 21st-Century Maritime Silk Road was constructed to explore the status quo of the centrality and connectivity of the nodal cities in Fujian Province and the core influencing factors of the firm interlocking network. Furthermore, policy suggestions on promoting the centrality and hierarchical structure of nodal cities in Fujian Province in the regional city network were made based on the core influencing factors. The aim was to promote the construction of a core area of the 21st-Century Maritime Silk Road in Fujian Province and to establish gateways from the South China Sea into the surrounding Southeast Asian countries for cooperation.
4. Discussion and Conclusions
With the constant development of information technology in recent years, the development of cities has developed beyond their own boundaries and has had closer connections and interaction with cities and regions in other countries, with a diversity of global or regional city networks being formed. The effective identification of the city network structure is related to the sustainable development of the region. Therefore, we based our data on the headquarters and branches of enterprises in information-related industries, and this study analyzed the structural features of the firm interlocking network in the nodal cities along the southeast coast of China and in Southeast Asian countries on the 21st-Century Maritime Silk Road, identifying the core influencing factors of the network’s centrality. The following conclusions have been drawn:
According to the spatial structures of the inter-city connection network already formed in the spatial range of the south route of the 21st-Century Maritime Silk Road, a circular connection structure has been formed within the region, and it gradually drives other cities in the region to further integrate into the development of the city network. Different levels of cities play their role in the connections in the network. The network is led by the core nodal cities, is driven by the secondary core nodal cities, and is supported by the backbone cities and the ordinary core nodal cities;
From the perspective of the centrality of the city network, Shanghai, Guangzhou, and Shenzhen, China, are the basis for China “going global” in relation to the construction of the Silk Road in Southeast Asia. Cities such as Singapore, Manila, and Kuala Lumpur represent the foothold beyond the Chinese borders this study has focused on. From the perspective of the connectivity of the city network, a regional city network has been formed based on inter-regionally interconnected cities in China and Southeast Asian countries. Meanwhile, the connectivity between the nodal cities in the Chinese section and the ones in Southeast Asian countries is better than that between Chinese nodal cities;
The cities in Fujian Provinces are not playing an important role in the regional city network. Fujian and Xiamen belong to the third level of cities, namely the backbone cities, and Quanzhou belongs to the fourth level and is an ordinary nodal city. None of these cities are playing a dominating or driving role. Therefore, it is urgent to improve their centrality in the regional city network;
The connectivity of the cities in Fujian Province is relatively low in the regional city network. Although Fuzhou and Xiamen are widely connected with other cities, the strength of the connections is much weaker than that of the core nodal cities and secondary core nodal cities. Quanzhou does not have connections with most of the cities in the region, resulting in it having a low connectivity in the regional network;
The three dimensions of policy coordination, financial integration, and technology exchange in the three cities of Fujian Province need to be strengthened despite the achievements made in the three dimensions of facility connectivity, unimpeded trade, and closer people-to-people bonds. The low level of investment in technology resources in all three cities reflects, to a certain extent, the neglect of science and technology development in Fujian Province. Therefore, Fujian Province should try to realize rapid development and catch up with other cities in the regional city network by investing more in science and technology.
Based on the above conclusions, the following suggestions have been made regarding the optimization of the centrality and connectivity of the cities in Fujian Province in the regional city network that further support Fujian’s construction of a core area of the 21st-Century Maritime Silk Road.
In terms of policy coordination, Fujian Province needs to actively enhance exchange and communication with the governments of Southeast Asian countries, establish a regular exchange mechanism, and promote pragmatic cooperation between governments. A favorable institutional environment should be provided to attract high-quality enterprises and to strengthen the exchange of factors with international cities.
In terms of financial integration, Fujian Province should promote the construction of economic and trade cooperation platforms and should explore an open economic system. The China (Fujian) Pilot Free Trade Zone can serve as an engine to drive foreign investment into sectors such as high-tech industries. In addition, the province can support enterprises to go public and raise capital in countries and to regions along the Maritime Silk Road, guiding and supporting qualified enterprises to build economic and trade cooperation zones outside of China.
In terms of technology exchange, Fujian Province should focus on strengthening technological cooperation with countries and regions along the route, enhancing its strength, and accelerating the construction of influential science and technology innovation centers in the region. Thus, Fujian Province should further promote the gathering, transfer, and diffusion of scientific and technological innovations among countries and regions along the Maritime Silk Road and should strengthen the connectivity of Fujian Province in the future regional spatial pattern reshaped by information-related industries.
In terms of facility connectivity, unimpeded trade, and closer people-to-people bonds, Fujian Province should maintain and consolidate its advantages. In addition, the province needs to continuously deepen the core area’s role in leading, gathering, and affecting other areas in various fields such as connectivity, economic and trade cooperation, and people-to-people exchanges.