Plastisphere in action: evidence for an interaction between expanded polystyrene and dunal plants

Area of Science:

• Marine Biology
• Ecology
• Environmental Science

Background:

• Plastic litter, particularly expanded polystyrene (EPS), poses a significant threat to coastal ecosystems.
• While the impact of plastic on fauna is well-documented, the interaction between EPS litter and coastal flora remains understudied.

Purpose of the Study:

• To investigate the interaction between expanded polystyrene (EPS) beach litter and living plants.
• To provide the first evidence of EPS-plant interactions in a sandy beach ecosystem.

Main Methods:

• Sampling of 540 expanded polystyrene (EPS) items from a Tyrrhenian central Italy sandy beach.
• Examination of EPS items for evidence of interaction with plant life, such as perforations and root presence.
• Identification of plant species associated with the EPS litter.

Main Results:

• Approximately 5% of sampled EPS items showed evidence of interaction with plants.
• Roots from three plant species—Phragmites australis, Spartina versicolor, and Anthemis maritima—were found on or within the EPS.
• No apparent relationship was observed between the size of EPS items and the presence of plants.

Conclusions:

• This study presents the first evidence of expanded polystyrene (EPS) litter interacting with living plants on a sandy beach.
• The findings suggest a previously undocumented ecological role for EPS in coastal plant communities.
• Further research is required to determine if plant colonization on EPS is random or selective.