Epiphytic lichen biodiversity and species distribution in the area of the University Campus of Salerno (Italy).

Dario Nicola Tangredi ¹, Francesca Giuliano ¹, Angela Cicatelli ¹, Francesco Guarino ¹, Stefano Castiglione ¹

University of Salerno ¹

Lichens are symbiotic associations between fungi (mycobionts), primarily ascomycetes, and green algae or cyanobacteria (photobionts). This symbiotic relationship is one of the most successful examples of fungi obtaining carbohydrates, with nearly one-fifth of all known fungal species being obligate lichen-formers. Unlike plants, lichens lack a protective outer layer and thus absorb nutrients directly into their thalli from rainwater and the atmosphere. Epiphytic lichens are among the most important biomonitors of environmental pollution. They serve as sensitive indicators to assess the biological effects of pollutants by observing changes at community or population levels, and as accumulative monitors of persistent pollutants by analyzing their trace element content. The aim of this study was to evaluate, for the first time, the epiphytic lichen biodiversity and species distribution in the area of the University Campus of Salerno, localized in the southern Italy and covering a total surface of 1.200.000 m2. Epiphytic lichen thalli were collected in 20 square plots (33x33 m), from May 2022 to April 2024 in the established sampling units (SUs) of the University Campus. In this context, the lime trees with subacid bark were used. The different lichen species were characterized in the laboratory by means stereomicroscope, optical microscope, and chemical reagents commonly used in lichenology studies. Color, morphology and different structures of thalli were described. A high abundance of nitrophyc (e.g., Xanthoria parietina) crusted (e.g., Lecidella elaeochroma) and foliose (e.g., Punctelia subrudecta) macrolichens were identified (20). The lichen biodiversity index (LBI) ranged between 17 and 103, and an interesting trend was revealed along the SUs. From the SU located near the bus station (LBI value of 44), toward the internal area of the campus (LBI value of 68), an increasing gradient in the LBI was detected, suggesting an improvement of the air quality. However, the species of epiphytic lichens identified are recognized for their ability to tolerate major atmospheric pollutants, such as NH3 and nitrogen oxides. The LBI values recorded in the large part of the SUs can be attributable not only to a great naturalness of the site but also to a different influence of the winds, which carry pollutants along the different areas of Campus. Although the study area is in an urban context, the lichen biodiversity was very high, indicating a good degree of naturalness of this area.

Main author career stage: PhD student

Contribution type: Talk

First choice session: 6. Plants, Fungi and Society

Second choice session: 4. Structure, physiology, and development