Xina Ji

Maritime transport is a vital pillar of global trade, while its CO ₂ emissions have become an increasingly pressing concern. ICT development may provide a new perspective for maritime decarbonization. Using cross-country panel data for 111 countries from 2019 to 2023, this study examines the impact of national ICT development on maritime transport CO ₂ emissions and further investigates the nonlinear role of maritime transport scale. The results show that improvements in ICT development significantly reduce maritime transport CO ₂ emissions. However, the emission-reduction effect of ICT gradually weakens as maritime transport scale expands and exhibits a significant threshold effect. When maritime transport scale remains below the threshold, ICT has a significant emission-reduction effect; once the threshold is exceeded, this effect declines. These findings indicate that digital infrastructure development can help reduce maritime transport CO ₂ emissions, although its effectiveness is constrained by the scale of maritime activities. This study provides cross-country empirical evidence on the relationship between digital infrastructure and maritime transport CO ₂ emissions and offers policy implications for incorporating ICT development into maritime decarbonization strategies.

Introduction: Against the backdrop of the strong interdependence between global energy markets and maritime transport systems, fluctuations in crude oil prices may influence tanker port operations through adjustments in trade organization and transportation decisions. Methods: Using a panel dataset covering 20 countries over the period 2018–2023, this study employs a two-way fixed effects model to identify the impact of oil price shocks on tanker port performance and further conducts robustness checks using a double machine learning approach. Results: The results reveal pronounced loading–discharging asymmetries in the transmission of oil price shocks within the port operation chain. The effects are concentrated on the loading side: increases in oil prices significantly raise the median time vessels spend in port, the average gross tonnage of arriving tankers, and the average deadweight tonnage per vessel. In contrast, these three indicators are not statistically significant on the discharging side. Discussion: From the perspective of port operations, this study provides additional empirical evidence on the transmission effects of oil price shocks. The findings not only offer Guida volatility but companies and port authorities in assessing operational pressure, optimizing resource allocation, and enhancing system resilience under oil price volatility, but also highlight the importance of incorporating energy market shocks into port operation monitoring and risk governance frameworks.

Air pollution caused by shipping-related activities has adversely affected public health and environmental quality in port cities. However, applying digital technologies offers new pathways to mitigate such pollution. Based on panel data from 52 coastal port cities in China from 2016 to 2020, this study employs a two-way fixed effects model to analyze the impact of the digital economy on shipping-related PM_2.5 pollution. Additionally, a panel threshold model is used to examine the threshold effect of port size in the relationship between the digital economy and shipping-related pollution. Heterogeneity analysis is further conducted from two dimensions—vessel types and PM_2.5 components—to explore the variations in the digital economy’s emission reduction effects. The results show that the development of the digital economy significantly reduces shipping-related PM_2.5 pollution levels, and this emission reduction effect strengthens as port size expands. Furthermore, there are significant differences in the emission reduction effects across different vessel types and PM_2.5 components. These findings contribute to understanding the mechanisms through which the digital economy mitigates shipping-related pollution and provide a scientific basis and policy support for promoting the green development of port cities and the shipping industry.

Introduction: Coastal tourism has become an important pillar of economic growth in China's coastal regions, yet no quantitative research has analyzed the relationship between coastal tourism and marine pollution.Methods: This study, within a multivariate framework, comprehensively examines the impact of coastal tourism on marine pollution by employing various econometric techniques and focusing on four different types of marine pollutant discharges: chemical oxygen demand (COD), petroleum (PET), ammonia nitrogen (NHN), and total phosphorus (TP).Results and discussion: Panel cointegration tests confirm a long-term relationship between coastal tourism and these four types of marine pollutant discharges. In the long run, coastal tourism has a significantly negative impact on COD, NHN, and TP. The results of Pooled Mean Group (PMG), Fully Modified Ordinary Least Squares (FMOLS), and Dynamic Ordinary Least Squares (DOLS) estimators show that for every 1% increase in coastal tourism revenue (TOUR), COD decreases by 0.734%, 0.536%, and 0.952% respectively; NHN decreases by 0.746%, 0.340%, and 1.633%; and TP decreases by 5.169%, 0.899%, and 0.334% respectively. However, the impact of coastal tourism on PET is not significant. The Dumitrescu-Hurlin (D-H) panel causality test results indicate different causality patterns between coastal tourism and various marine pollutant discharges. Specifically, there is a bidirectional causality between coastal tourism and COD, NHN, and a unidirectional causality between coastal tourism and PET, TP. Moreover, heterogeneity analysis reveals that coastal tourism does not significantly reduce all marine pollutant discharges in low-and middle-income coastal regions. Furthermore, compared to the central and southern coastal regions, the coastal tourism of northern regions has not significantly reduced marine pollution. This study can provide policymakers with references for developing coastal tourism and reducing marine pollutant discharges.

Operating the China Railway Express (CRE) is a primary strategy for promoting international trade and investment between China and Europe. Since the inception of the CRE in 2011, the number of operational routes and connected cities has steadily increased. This study investigates the impact of the establishment of the CRE on foreign direct investment inflows in Chinese prefecture-level cities. To perform our analysis, we used panel data of 250 cities in China from 2004 to 2018, and applied the difference in differences (DID) model as a quasi-natural experiment. The results demonstrated that the operation of the CRE had a positive and significant impact on urban FDI inflows, particularly in small and medium-sized cities, low-income cities, and inland cities in China. The robustness of the results was verified using the DIDM and PSM-DID methods.

항만 간 경쟁이 심화되면서 항만효율성은 더욱 중요하게 인식되고 있다. 항만효율성 개선을 통하여 항만의 지속 가능한 개발을 촉진함과 동시에 지역 및 국가 경제성장을 도모하는 것은 항만운영자 뿐만 아니라 지방 및 정부의 주된 관심사이다. 본 연구는 중국의 황금내륙수로인 양쯔강 상의 내륙항만들의 경쟁이 치열해지고 있는 상황에서 2010년부터 2017년까지의 패널자료를 이용하여 장강변 14개 주요 내륙항의 효율성을 분석하고 시간에 따른 항만 효율성의 변화를 살펴보고자 하였다. 동시에 14개 내륙항구를 양쯔강 중류, 상류, 하류 항만군으로 나누어 유역별 항만효율성 수준의 차이를 비교 검토하였다. 특히 본 연구를 수행하기 위해 3단계 DEA 분석 방법을 적용하여 효율성 평가에 영향을 미칠 수 있는 환경적 요인과 통계적 노이즈의 영향을 최대한 배제하여 항만 자체의 순수 상대효율성을 평가하였다. 분석결과, 1단계 효율 평가 결과와 3단계 효율 평가 결과 포트의 효율 값에 뚜렷한 차이가 있음을 확인하였고, 구체적인 결과를 해석과 함께 본문에서 제시하였다. 또한 하류항만들의 효율성이 중 · 상류 항만에 비해 상대적으로 높은 효율성을 보이고 있음을 알 수 있었다.

본 연구는 중국의 35개 항만을 대상으로 2018년부터 2020년까지의 분기별 데이터를 사용하여 COVID-19가 중국 항만의 물동량에 어떠한 영향을 미쳤는지를 분석하고자 하였다. COVID-19의 설명변수는 항만이 위치한 성(省)의 분기별 신확진자 수와 COVID-19 발생 전후를 시간더미로 고려하여 교호작용항으로 설정함으로써 항만이 입지한 각 지역의 COVID-19의 심각성을 고려하고자 하였다. 특히 거시 경제 및 국제 무역의 영향을 최대한 통제하고 COVID-19가 항만 물동량에 미친 직접적 영향을 파악하고자 System-GMM 모델을 적용하여 분석하였다. 동시에 COVID-19로 인한 중국의 내륙교통통제가 항만물동량에 간접적 영향을 미쳤을 것으로 보고, 내륙교통통제의 매개효과를 추가적으로 분석하였다. 분석 결과, COVID-19는 정적ㆍ동적패널데이터 분석모형 모두에서 통계적으로 유의미하게 부정적 영향을 미치고 있음이 확인되었다. 아울러 내륙교통통제 역시 COVID-19와 항만 물동량 사이에서 부분 매개효과가 있음이 분석되었다.