Abstract
Nigeria’s maritime sector holds significant potential for advancing sustainable economic growth, yet it remains constrained by inefficiencies in transport operations, weak environmental standards, and limited global integration. This study investigates the combined and individual effects of Sustainable Maritime Transport (SMT), Environmental Shipping Index (ESI), and Liner Shipping Connectivity Index (LSCI) on maritime-sector development in Nigeria between 2007 and 2022. Secondary data were obtained from the Central Bank of Nigeria, Nigerian Ports Authority, UNCTAD, and the International Association of Ports and Harbours. Analytical tools, including SPSS, EViews, AMOS, and NVivo, were employed to perform regression, diagnostic, and thematic analyses. The regression results reveal that SMT (β = 0.574, p < 0.01), ESI (β = 0.366, p < 0.01), and LSCI (β = 0.401, p < 0.05) each have a significant positive effect on maritime GDP. The combined model indicates that the three variables jointly explain 83.5% of the variation in Nigeria’s maritime-sector output. These findings validate the Sustainable Development Theory and Resource-Based View (RBV) by demonstrating that economic efficiency, environmental stewardship, and global connectivity are mutually reinforcing drivers of maritime sustainability. The study concludes that advancing Nigeria's blue economy requires a coordinated policy framework that integrates port modernization, environmental governance, and trade facilitation. It contributes to maritime scholarship by proposing a triple-helix framework that interlinks sustainable transport, environmental performance, and connectivity as strategic levers for sustainable maritime development in emerging economies.