The ongoing expansion of blue growth activities necessitates robust methodological frameworks to balance industrial development with ecological preservation and integrated resource governance. This research investigates the economic spillover effects of Maritime Spatial Planning (MSP) strategies by employing a multi-regional input-output approach based on Supply and Use Tables (SUT). This model is embedded within a specific satellite account designed for the Italian maritime sectors.

The investigation targets key sectors of the Blue Economy—including fisheries, aquaculture, maritime transport (freight and passengers), coastal tourism, and offshore energy—across three strategic areas: the Northern Adriatic, the Strait of Sicily, and the Northern Tyrrhenian Sea. By simulating exogenous shocks on sectoral output and final demand, the study quantifies the resulting socio-economic impacts.

The findings demonstrate a marked territorial divergence in multiplier impacts, driven by the specificities of local productive structures. Ultimately, the paper introduces a systematic and scalable accounting tool that enables policymakers to incorporate data-driven economic assessments into the broader governance of marine spaces.