Plankton biodiversity through remote sensing and omics in the Mediterranean Sea – PETRI-MED

The objective of PETRI-MED is to develop novel strategies to determine and monitor the status and trends of microbial plankton biodiversity in the entire Mediterranean Sea, supporting the assessment of the impact of ecological connectivity on local biodiversity and ecosystem functioning.

This will be achieved following a highly multidisciplinary approach, capitalizing on the large potential offered by the past and ongoing satellite missions, complemented with field measurements (optical, physical, chemical, and genomic), biogeochemical/ecosystem/marine currents modelling, and artificial intelligence technologies. PETRI-MED will allow to:
- identify spatio-temporal patterns in the microbial plankton community distribution and biodiversity;
- assess key controls of biodiversity patterns, including ecological connectivity, natural (e.g., river runoffs and marine currents) and human-related forcing (e.g., use of land and coastal ecosystems).
This in turn will open the way to:
- regional and basin-level seascape spatial assessments, by combining estimates of plankton biodiversity with in-situ measured and remotely-sensed physical and biogeochemical patterns.
- the identification of fragmented habitats and the recognition of new zones or ecological corridors for maintaining and restoring biodiversity.

Two AI-based algorithms will be developed.
The first algorithm will be applied for the generation of the global Mediterranean Sea product relying on Multi-spectral satellite Ocean Colour observations and in situ and/or modelled physical/biogeochemical variables as salinity, temperature, marine currents, mean/eddy kinetic energy, dissolved nutrients and oxygen. In-situ omics measurements (metabarcoding and metagenomic) will be used to train and verify the algorithm.
The second algorithm, based on the same architecture of the first one, will be specifically tailored for each partner’s region of interest and will include the information provided by the omics as well as key regional physical indicators (e.g. cross-shore or longshore transport index) that aim to assess the role of connectivity.
Output parameters will be:
- the relative contributions of phytoplankton groups, bacterio- and archeo-plankton and an Alpha-Diversity Index for plankton based on the Shannon index summarizing this information.
- an Ecosystem Function Indicator, based on the distribution of specific functional genes that have precise ecosystem roles/functions potentially linked to deteriorated/healthy ecosystem.

Results will be validated against independent measurements collected in selected regions of interest with well-established oceanographic infrastructures and/or long-term monitoring of physical and chemical data.

Finally, a first data exploitation exercise will be conducted focusing on two case-study areas corresponding to extensively studied zones for ecological connectivity research in the North-western Mediterranean Sea and in the Northern Adriatic Sea.