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Crude oil transportation is a vital component of the global energy supply, and the global Crude Oil Maritime Transportation Network (COMTN) plays a crucial role as a carrier for crude oil transportation. Once the network faces attacks that result in the failure of certain routes, a severe threat is posed to the crude oil supply security of importing countries. Therefore, it is crucial to evaluate the reliability of the COMTN. This study proposes a model for evaluating the reliability of the imported COMTN by analyzing the impact of node failures. Firstly, the network is constructed using complex networks (CNs) theory, with ports, canals, and straits as nodes, and shipping routes as directed edges. Secondly, based on the Weighted Leader Rank algorithm, a comprehensive evaluation metric for CNs is established, and a node importance assessment model is developed to rank the nodes accordingly. Thirdly, a case study is conducted using China's imported COMTN as an example, evaluating the connectivity reliability (CR) under random and deliberate attack scenarios. Finally, measures and recommendations are provided to enhance the CR of China's imported COMTN. The findings indicate that deliberate attacks pose a greater threat, and reliability varies across maritime routes, with the Americas route exhibiting higher reliability compared to the Middle East and Southeast Asia routes. The results of this study can provide relevant recommendations for policy makers. The model proposed in this study can also be applied to other countries and regions to assess the connectivity reliability of their local COMTNs and develop appropriate measures for the results. [ABSTRACT FROM AUTHOR]

The exacerbation of the concentration of population and economic activities in a few core metropolitan areas has become an urgent issue for China's regional development, and necessitates a more polycentric spatial development pattern. Transportation infrastructure improvement can serve as a vital instrument to achieve the objective of polycentric spatial development. Focusing on the 10 megaregions of China, this research examines a fundamental issue for China's urban and regional development in the context of massive investment in highway and railway: the impacts of road and rail network on the spatial pattern of growth and development. Using the county-level national censuses of 1982, 1990, 2000, and 2010 and the historical transport network geographic information system (GIS) data, this paper analyzes the differentiated effects of road and rail for population growth. The research results revealed the stronger positive growth impacts of rail compared with road, and further examination indicates that railway has stronger positive impacts for regional growth in the less-developed areas. [ABSTRACT FROM AUTHOR]

Understanding the origins and introduction pathways of invasive species is a fundamental issue for invasion biology, which is necessary for predicting and preventing future invasion. Once an invasive species is established in a new location, this location could serve as a stepping-stone for further invasions. However, such "stepping-stone" effect has not been widely investigated. Using the published literature and records, we compiled the first found locations of 127 top invasive species in China. Our study showed that the most common landing spots of these invasive species were Hong Kong (22 species) and Taiwan (20 species), which accounted for one-third of the invasive species in China. Our analysis revealed that the invasive species in mainland China were more likely to transport from Hong Kong than Macau, a neighboring region with a similar area and colonial history. Similarly, more invasive species were also first landed on Taiwan than Hainan, a nearby island sharing similar climate conditions. Together, our findings indicate that Hong Kong and Taiwan are the most important stepping-stones for invasive species to the mainland of China and suggesting that the increasing trade exchange of China's coastal ports constitutes a potential risk for the spread of more invasive species. We suppose that they would be the future stepping-stones for invasive species to the mainland of China and these coastal ports regions where improved biosecurity is needed now. [ABSTRACT FROM AUTHOR]

Coal plays a vital role in the socio-economic development of China. Yet, the spatial mismatch between production centers (inland Northwest) and consumption centers (coastal region) within China fostered the emergence of dedicated coal transport corridors with limited alternatives. Serious problems of energy shortage and power rationing have already affected southeastern China. At the same time, enormous interregional coal transfers face a lack of transport capacity along the transport system. Based on first-hand statistics, a disaggregated analysis of coal distribution patterns since the late 1970s provides novel evidences about the local effects of macroscopic trends, such as the shift from dominant exports to dominant imports in terms of changing traffic concentration levels and distribution patterns among routes and ports. The spatial evolution of coal distribution is also discussed in terms of related industry linkages and local influences, coal trade policies and market pricing, port system evolution, and transport network planning. The paper also discusses possible improvements of the current situation through enhancing multimodal transport based on a review of current policies. [ABSTRACT FROM AUTHOR]

Although the construction of China’s high-speed rail (HSR) network only started in 2003, the network is already the largest in the world. This paper analyses the impact of the evolving HSR network on the accessibility by HSR and conventional ground transport of 333 prefecture-level cities and 4 municipalities. This paper employs three indicators of accessibility, and analyses three Scenarios. It shows that the HSR network will bring about substantial improvement in accessibility, and lead to national time–space convergence, but will also increase the inequality of nodal accessibility between eastern, central, and western regions, between cities with different sizes of population (excluding the case of the daily accessibility indicator) and between cities that differ in the shortest distance to HSR stations. The HSR network enlarges internal disparities in each of the regions and the five types of cities. The internal inequality of nodal accessibility in all three Scenarios generally increases from the eastern region via the central region to the western region, as well as from very large cities to small cities, varying inversely with the level of economic development and population size. Spatially, accessibility increases generally conform to the distance decay rule but with minor fluctuations. The 50 cities with the largest increases in accessibility are mostly located 50 km or less away from HSR stations and have populations of over 3 million, with the smaller ones located along HSR lines or around large cities such as Beijing, Shanghai, and Guangzhou. As time progresses, the planned HSR network will result in more balanced development, but regional disparities in accessibility will still be greater than before the construction of the HSR. [ABSTRACT FROM AUTHOR]