The National (Marine) Biodiversity Observatory System implemented within NBFC-Spoke1 has the main objective of harmonizing the current marine-coastal biodiversity knowledge and integrating it in databases, in order to provide the information and priorities to plan new conservation scenarios for reaching EU targets. In response to the challenges posed by the heterogeneity and fragmentation of biodiversity knowledge, a Marine Spatial Data Infrastructure (MSDI) has been implemented. Its primary objective is to consolidate and maintain biodiversity data, facilitate their reuse promoting FAIR principles: Findability, Accessibility, Interoperability, and Reusability. The main user interface of this infrastructure is a Geoportal integrating biodiversity data, environmental variables, and human uses organized into thematic groups:

· Pilot sites;

· Monitoring:

· Protection and conservation;

· Human uses;

· Biodiversity;

· Geodiversity;

· Topography.

The geoportal is a free accessible user-friendly tool, where the user can visualize data in an integrated manner, identify and query spatial objects and their related information (e.g. time series). Through the geoportal, users can also explore metadata, which ensure data preservation and reusability, and ask for data to providers.

The architecture is designed to fit all standards and best practices for data collection, integration, availability, and shareability, following the FAIR principles. Standardization ensures interoperability with other infrastructures, and enhances data discoverability and preservation. The system can support the exploration of ecosystem dynamics under environmental and anthropogenic pressures, and maritime spatial planning processes. The geoportal could be a relevant tool for future analyses that will focus on developing cost-effective ecological indicators and innovative biodiversity monitoring tools, as well as assessing the vulnerability of crucial Mediterranean habitats to climate change-related stressors.