TEMPORAL CHANGES IN COMMUNITIES ON PLASTIC PANELS WITHIN A POLLUTED MARINE ENVIRONMENT

CAMBIAMENTI SU SCALA TEMPORALE NELLE COMUNITÀ SU SUBSTRATI DI PLASTICA IN UN AMBIENTE MARINO INQUINATO

Abstract

This study examined community succession on polystyrene panels deployed for 25 weeks in a harbour impacted by human activities. Microbial and eukaryotic colonisation of plastics was studied using eDNA metabarcoding targeting 16S and 18S rRNA genes. The prokaryotic biofilm community was dominated by Rhodobacteraceae (17%) and Flavobacteriaceae (18%), with only minor changes over time. Concernig eukaryotes, the early stages of colonization were dominated by Alveolata (63%) and Stramenopiles (24%), while the later stages shifted to Chlorophyta (20%) and Opisthokonta (94%). Diversity analyses based on ASVs showed that alpha diversity ranged from 1,875–2,481 for prokaryotes and 159–405 for eukaryotes.. Moreover, potential plastic-degrading bacteria were identified in the prokaryotic community. The ecological dynamics of the eukaryotic community showed the dominance of heterotrophic microrganisms. These findings confirm that plastics may act as substrates and vectors for diverse microbial and eukaryotic assemblages, posing ecological risks to marine ecosystems.