俄乌冲突背景下“一带一路”沿线原油海运网络 结构特征及变化分析.

The impact of international geopolitics on transportation network patterns is an important topic in economics and transportation geography. Previous studies have often overlooked the diversity of domestic crude oil transportation among countries due to limitations in statistical data, focusing mainly on national-level node selection. Additionally, the evolution of network characteristics is predominantly analyzed through long-term descriptive approaches, lacking specific contextual analyses of network evolution. This study investigates changes in the maritime crude oil transportation network along the Belt and Road Initiative (BRI) routes against the backdrop of the Russia-Ukraine conflict, offering new evidence for research in this field. Using AIS (Automatic Identification System) ship trajectory big data and complex network analysis methods, this study analyzes the overall characteristics, node importance, core-periphery structure, and clustering of the maritime crude oil transportation network along the BRI routes from 2019 to 2022. Furthermore, it examines the impact of maritime network changes on the stability of crude oil imports to China. Our findings reveal several key points. 1) The closeness, strength, and accessibility of network connections between ports show an initial increase followed by a decreasing trend. The direction of the overall network characteristic changes in the periods 2019- 2020 and 2020-2022 are opposite, with a greater magnitude in the latter period. In recent years, particularly following the Russia-Ukraine conflict, the scale-free nature of the network has continuously increased, accompanied by an increase in the concentration of crude oil shipping connections. This concentration, notably evident towards export destinations, reflects a shifting pattern in the crude oil supply demand landscape, spatially manifested as China replacing some of its crude oil shipping connections with the Middle East, thus reducing its reliance on Russian crude oil shipments. 2) The comprehensive importance of export ports has become more prominent, with a slight decrease followed by a significant increase in recent years. The importance of ports in Russia's Far East region has notably increased, reflecting a shift in Russia's crude oil export center eastward after the Russia-Ukraine conflict. The network structure transitioned from single-core to multi-core to single-core with export ports occupying more central layers. 3) Initially, there was a continuation of the core-periphery and clustering structures, but later, there was significant structural reorganization. In 2020, the core-periphery structure and clustering in terms of core ports, geographical distribution, and cluster size were largely the same as corresponding clusters in 2019; however, by 2022, a noticeable structural reorganization emerged. 4) Changes in maritime networks significantly and heterogeneously affect China's crude oil import stability. At the network level, import stability initially increases and then decreases, with the decline in the later period far exceeding that in the earlier period. At the port level, compared to ports around Bohai Bay and the Yangtze River Delta, ports along the southeastern coast, Pearl River Delta, and southwestern coast were more affected by the Russia-Ukraine conflict in terms of crude oil import stability. China responded to the risk of instability in its crude oil import network against the backdrop of the Russia-Ukraine conflict by adjusting its sources and proportions of imports from different ports. This study provides scientific evidence for a deeper understanding of the impact of geopolitical events on China's oil imports and the formulation of national energy security strategies. [ABSTRACT FROM AUTHOR]

国际地缘政治对运输网络格局的影响是经济地理和交通地理的重要议题之一，探究俄乌冲突背景下 “一带一路”沿线原油海运网络结构特征变化，可为该领域研究提供新的论据。文章采用 AIS船舶轨迹大数据 和复杂网络分析法，分析了2019—2022年“一带一路”沿线原油海运网络整体特征、节点重要性与核心边缘和 组团耦合结构的变化特征，并探究了海运网络结构变化对中国原油进口稳定性的影响。结果表明：1） 海运格 局发生了结构性演变。港口间的联系密度、强度和网络通达性均呈现先增后减趋势；网络无标度特性不断增 强，原油海运向部分主要联系集聚，出口端更加明显；俄乌冲突后中国与中东原油海运联系取代了部分中俄原 油海运联系。2） 海运港口重要性格局与核心边缘结构处于动态变化中。出口港综合重要性先略有降低，俄乌 冲突后大幅增加；网络结构经历了单核―多核―单核的转变，俄乌冲突后国际原油市场供需格局改变，较大规 模的出口港对原油海运网络中广大进口港和其他中小规模出口港的控制力明显加强。3） 海运网络核心边缘与 组团耦合结构前期变化稳定，后期变化突出。俄乌冲突后核心边缘与组团耦合结构在核心港、地理分布和组团 规模方面发生明显变革。4） 海运网络变化对中国原油进口稳定性的影响显著且具有异质性。中国原油进口网 络的稳定性先增后减，俄乌冲突后的降幅远大于冲突发生前的增幅；相比环渤海湾和长三角港口，东南沿海、 珠三角和西南沿海港口的原油进口稳定性受俄乌冲突影响更大。 [ABSTRACT FROM AUTHOR]