Factors influencing the diversity and distribution of epiphytic lichens and bryophytes on the relict tree Zelkova abelicea (Lam.) Boiss. (Ulmaceae)

Abstract

Trees have a crucial importance in the functioning of ecosystems on Earth. They are among the largest and longest-living taxa and provide habitat and shelter to numerous species belonging to diverse groups of organisms. Relict trees are of particular interest through their history of survival and adaptation, and because they potentially shelter rare or threatened organisms today. We investigated for the first time the diversity and distribution of epiphytic lichens and bryophytes found on the Cretan (Greek) endemic and relict phorophyte Zelkova abelicea (Ulmaceae). Our results showed that Z. abelicea hosts a high number of epiphytes. The Levka Ori mountain range in western Crete seems to be a hot spot for epiphytic lichens on Z. abelicea. Bryophytes had the highest diversity on Mt Kedros in central Crete but were absent from several other sites. Moreover, 17% of the studied lichens were recorded for the first time for Crete and 5% have never been recorded for Greece. Geographical position and browsing intensity seem to be important factors influencing the epiphytic community encountered. Tree morphology (dwarfed or arborescent) was also significant in influencing community composition although it was not possible to dissociate this factor from the effect of topography. Dwarfed individuals were found to have as much epiphytic diversity as arborescent trees. Ecological indicator values showed that high epiphytic diversity was found in some sites despite signs of eutrophication and disturbance due to pastoral activities and suggest the co-occurrence of both disturbance tolerant and sensitive species. Our results show how little is known about the biodiversity of Cretan phorophytes and highlights the need for further research on the topic.

The impact of climate aridification on rare lichen communities

“…Allen & Lendemer (2016) emphasized the vulnerability of high-elevation lichens to climate change, highlighting a trend also observed in our study, where rare lichen species exhibit significant sensitivity to changing moisture regimes. Similarly, Brunialti et al (2021) and Fazan et al (2022) explored the reproductive strategies of epiphytic lichens, providing a context for understanding how aridification might affect lichen reproduction and, consequently, their long-term survival and distribution. Honegger (2022) and Khastini et al (2019) provided foundational knowledge on lichen biology and ecology, reinforcing the importance of studying lichen as indicators of environmental health.…”

“…Globally, the study of lichens is gaining increasing importance in ecological research due to their role as sensitive bioindicators of environmental health (Orlov et al, 2022). Lichens, with their unique symbiotic nature, respond acutely to changes in atmospheric conditions, making them valuable in assessing air quality and the impact of pollutants (Sinigla et al, 2021;Fazan et al, 2022;Lawal et al, 2023). This sensitivity is heightened by their structural characteristics, such as the lack of a protective cuticle, allowing direct exposure to environmental factors (Floqi et al, 2009).…”

Contribution to the knowledge of the lichen biota of Pinus nigra stands in Greece

“…Arcadia 2018, Christensen 2014, 2018, 2020) and analysis of lichen communities is practically non-existent (e.g. Farzan et al 2022, Zoller et al 1977). The lichen biotas of Picea abies ( Christensen 2018) and Pinus sylvestris ( Christensen 2020) have recently been recorded.…”

“…12: 15120, 15125, 15142. − Recently reported new to Greece from Kriti byFazan et al (2022). New to Makedonia.Pseudevernia furfuracea (L.) Zopf, incl.…”

Importance, Tools, and Challenges of Protecting Trees

“…Additionally, among all 453 described vascular plant families, 191 are entirely woody (42%) [1]; thus, trees and other woody plants constitute more than 70% of the total biomass on Earth [8,11]. Due to this importance and domination of most terrestrial ecosystems, trees play an important role in maintaining biodiversity, providing food and habitat for countless microorganisms, fungi, climbers, invertebrates, and vertebrates [12][13][14]. Furthermore, trees were also indispensable for the development of our own species and are important for our survival today and in the future [9].…”