The analysis of geo-economic relations from an industrial scale provides valuable insights into comprehending the formation of the prevailing international industrial division of labor pattern and the distribution of interests among nations. Therefore, it becomes imperative to introduce a more microscopic industrial scale into geo-economic analysis to gain a deeper understanding of these dynamics. Taking the nations surrounding the South China Sea as the research object, using national trade data, based on the geo-economic tightness model and the industrial structure similarity coefficient model, this paper calculates the geo-economic connection tightness and industrial coopetition relationship on the national and industrial scales of the nations surrounding the South China Sea from 2003 to 2021, and uses the fixed-effect model to analyze the potential influencing factors. The results reveal several significant findings. Firstly, the overall geo-economic tightness among the nations surrounding the South China Sea exhibits an upward trend, accompanied by a gradual shift in the core area from the southern to the northern region. Within the context of the industrial scale, the tightness of geo-economic relations displays an overall growth trajectory; however, notable variations in growth rates are observed across different industries. Notably, the machinery and transport equipment industry experiences a substantially higher growth rate compared to other sectors. Moreover, the geo-economic tightness within the marine industry presents a three-core pattern, characterized by opposing dynamics between the northern, southern, and eastern regions. Secondly, the industrial competition and cooperation relationship between nations surrounding the South China Sea demonstrates a multipolar development trend, with significant disparities observed among nations. The coopetition relationships across various industries exhibit relative stability on the whole, lacking any evident trend towards competition or cooperation. Nevertheless, there exists an upward trend in the disparities among industries. Furthermore, the coopetition relationship within the marine industry displays notable variations among nations, with the overall level remaining relatively high; however, the scope for geo-economic cooperation remains limited. Finally, this paper emphasizes the influence of spatial factors, natural endowment factors, institutional factors, and cultural factors on geo-economic tightness and industrial coopetition relationships across different scales and industries. It is important to note that these factors exhibit distinct variations and exert varying degrees of impact in different contexts.

With the continuous improvement of human production innovation, the ontological cognition of ocean as a resource has gradually expanded from 'territorial' ocean to the field of high seas. The sustainable development of marine resources in the high seas is facing multiple threats. The delineation of protected areas on the high seas has become an important issue of global marine governance. From the perspective of human-ocean relationship, this paper studies the geo-setting system of high seas protected areas under the BBNJ, and puts forward the analytical thoughts and methods of high seas protected areas with geographical characteristics that China needs at present. First of all, this study deconstructs the human-ocean relationship in the high seas protected areas into the bottom layer and the operation layer. It reveals the human domain behavior of repair, maintenance and potential competition in the bottom layer, as well as the attributes of public, volumetric and dynamic ocean ontology. We simulate the human-ocean interaction process in the high seas protected areas in the operation layer, deconstruct the three links in the interaction process: foundation and support of human-ocean interaction, core of human-ocean interaction, premise and reflection of human-ocean interaction, and cover four subsystems: natural system, artificial system, relational system, and conceptual system. This leads to the marine geo-setting system of the high-seas protected areas, which is the core of human-ocean interaction. Secondly, this paper analyzes the marine geo-setting system of the high seas protected areas. According to the multiple interactions between human territorialization behavior and marine ontological attributes of the high seas protected areas, the paper summarizes the characteristics of the marine geo-setting system of the high seas protected areas into four aspects: subject diversity, spatial limitation, complex sensitivity and pattern variability and proposes that the marine environment is the supporting force; rules and institutions are the driving force; marine geo-relationships and geo-structure are the powering force; marine technology is the guarantee capability of evolution mechanism. Finally, according to the contents discussed in this study, combined with the current situation and the actual needs of China's participation in global marine governance, the policy suggestions for China's involvement in the demarcation of high seas protected areas are put forward.

The deepening development of globalization and the transformation of regionalization are driving the continuous reshaping of the global political and economic pattern, while overseas strategic pivots, with their prominent geographical influence, play a supporting role in a country's global strategic deployment. This research combined geopolitical theory, new state space theory and location theory to reveal the impact mechanism and logical framework of spatial selection of China's overseas strategic pivots (COSPs) at different scales. On this basis, it preliminarily constructed the spatial selection model of COSPs, and then proposed an action path to put the model into practice from the perspective of actors. The results show that: (1) Geopolitical theory, new state space theory and location theory respectively dominate the spatial selection of COSPs at higher scale, mesoscale and lower scale. Specifically, the five underlying motivations derived from the three-dimensional perspective of "power-capital-space" have driven the rimland between land and sea powers to become the soil for cultivating COSP regions and countries; as a specific form of state spatial selectivity, COSP areas should be selected from strategic functional areas in COSP countries that are deeply supported by state spatial projects and strategies; owing to superior location conditions and location demand, coastal or border hub cities, international ports and parks in COSP countries have become the spatial selection range of COSP cities, ports and parks. (2) Each of the above three theories has its own emphasis, that is, they respectively dominate the spatial selection logic of COSPs at different scales; and they are also nested with each other, which means that the spatial selection of COSPs at various scales will inevitably be influenced by the geopolitical environment, state spatial selectivity and location conditions, thus shaping the logical framework of spatial selection. (3) The spatial selection model of COSPs has the characteristics of interlocking and multi-directional flow. In practice, the basic concept of "government domination and multiple actors initiation" should be adopted to strengthen top-level design, decision-making assistance and technical breakthroughs. The results can enrich the strategic pivot research framework and provide theoretical reference and policy inspiration for enhancing China's geopolitical influence.