Fig 3 - uploaded by Gregor Kozlowski
Content may be subject to copyright.
Frequency of occurrence (%) of epiphytic lichens (dark grey) and bryophytes (white) growing on the investigated Zelkova abelicea trees on Crete.
Source publication
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 rar...
Context in source publication
Context 1
... 70 epiphytic species were recorded on Zelkova abelicea: 60 lichen species belonging to 21 genera and 10 bryophyte species belonging to eight genera (Fig. 3, Tables 2 & 3). Four lichen taxa common in Greece and Europe were the most abundant: Pleurosticta acetabulum (found on 33 trees), Xanthoria parietina (30 trees), Physcia tenella (27 trees) and Lecidella elaeochroma (26 trees). All other species were recorded on 20 or fewer trees. Eighteen species occurred only once. For bryophytes, ...
Citations
... 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). ...
... 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) These studies, along with ours, suggest a global trend of shifting lichen populations in response to climate change, emphasizing the need for targeted conservation efforts. ...
The global diversity of approximately 25,000 lichen species (e.g., from the genera Usnea, Cladonia, and Peltigera), including rare and endangered ones, highlights the importance of preserving their population in the State National Nature Park “Burabay”. The objective of this study was to investigate the distribution of rare lichen species in the territory of the State National Nature Park “Burabay,” located in the Akmola region of Kazakhstan, in the period from 2018 to 2022, with a particular focus on understanding how aridification may have influenced their presence and abundance. In the course of the study, methods such as route expeditions, the comparative morphological method, as well as some other special methods were used. The collection of information to systematize the taxonomic composition of lichens (genera Lobaria, Rhizocarpon, and Xanthoria) was carried out during route expeditions. The study identified 56 lichen species, with a focus on rare and protected species. Established in 2000, the park's rich biodiversity is showcased, including the discovery of three very rare species (Dermatocarpon miniatum, Psora lurida, and Verrucaria nigrescens) and four species requiring protection (Peltigera spuria, Cladonia coccifera, Haematomma ventosum, and Caloplaca aurantiaca). These findings are significant, considering the absence of data on these species since the 1982 Red Book of Kazakhstan (including genera such as Lecanora, Lecidea, and Pertusaria). The sensitivity of lichens to environmental changes (indicated by genera like Alectoria, Bryoria, and Cetraria) makes them ideal for monitoring ecological health through a cost-effective method known as lichen indication. The increase in the species count over the past five years (highlighting genera such as Stereocaulon, Solorina, and Thamnolia) suggests effective conservation efforts and underlines the park's ecological importance. The study's findings reveal that aridification is reshaping lichen communities in the park, emphasizing their sensitivity to climate change and the need for conservation strategies to address these changes and ensure the preservation of lichen biodiversity in the face of global climate change. The research contributes valuable data for future conservation planning and environmental assessments in the region, emphasizing the need to protect diverse lichen genera (e.g., Evernia, Ramalina, and Parmotrema) for ecological monitoring and conservation.
... A Shannon index = 0 indicates a community consisting of only one species. The poleotolerance index reflected the air pollution level in the area [43][44][45][46] and was assessed according to Truss [43]. ...
Because they are widespread and evolutionarily old, epiphytic lichens (ELs) play an important role in global forest ecosystems. ELs are abundant in Siberian forest ecosystems, which are highly vulnerable to climate change; thus, ELs can be important contributors to the carbon (C) cycle. This study aims to address the unknown role of tree-inhabiting ELs in the C cycle of forest ecosystems in Central Siberia, where the EL biomass ranges from 492 to 3200 kg per ha. The main finding of this study is that ELs in a hydrated state can generate CH 4 for an extended period (at least two weeks), as determined by an incubation method. At the same EL moisture level, EL CO 2 fluxes are species-specific. The pattern of the release or uptake of GHGs by ELs may also alter due to climate change, e.g., changes in precipitation regimes (such as more frequent extreme rainfalls and droughts). Therefore, the EL contribution to the C cycle in forest ecosystems should be assessed, e.g., via the modeling of C cycling. Furthermore, specific factors, such as the EL exposure on the phorophyte stem, the EL biodiversity, and the day/night GHG fluxes, should be considered for a more concise assessment of ELs' contribution to the C cycle of forest ecosystems and their response to ongoing and projected climate change.
... These results may be biased by the small sample size in that location, but could also mirror more adverse conditions, inhibiting normal seed and fruit development. Indeed, Fazan et al. (2022b) also showed poorer site conditions in Psiloritis than other sites hosting Z. abelicea trees. Nevertheless, since Christe et al. (2014) found strong genetic differences in Z. abelicea populations growing on each mountain range, we cannot rule out a possible genetic control that would be mirroring the longitudinal gradient found in terms of diaspore stem length and proportion of fruits with sound seeds. ...
In the tree genus Zelkova (Ulmaceae), diaspores show a unique morphology amongst woody angiosperms. Shoots with leaves and fruits detach and act as flying dispersal units. Surprisingly little attention has been given to these structures, and it is unknown whether the characteristics of these diaspores vary amongst species or within the range of a single species. The endemic Cretan Z. abelicea (Lam.) Boiss. is one of two Zelkova species occurring at the western end of the distribution range of the genus. This relict species grows in a typical Mediterranean climate, in conditions completely different from the warm and moist climate that occurred during the apogee of the genus in the Paleogene, or that are still found for the three East Asiatic species of the genus. Here we studied for the first time the characteristics of diaspores, including fruit traits, of Z. abelicea across the whole range of the species. We showed that most traits are very variable amongst individual trees but less so between mountain ranges and that only diaspore stem length and proportion of sound seeds per diaspore and per tree vary significantly amongst mountain ranges. We showed that trees from central and eastern Crete produce extremely low to null proportions of sound seeds and that those trees oftentimes are smaller and have shorter diaspores with less leaves and fruits. Furthermore, we found that diaspores that were severely affected by a gall midge species (Cecidomyiidae) produced less fruits, but that seed soundness was not significantly impacted by the presence or absence of the galls. The very low proportion of sound seeds found in central and eastern Crete raises concern about the long-term persistency and regeneration of the species in those areas.
... Indeed, from the 27 Collembola species recorded at Gerakari, twenty were found nowhere else, which indicates the uniqueness of the site and its dissimilarity with the other sampling sites. These results can be assessed based on the study by Fazan et al. [77], who found a richer diversity of epiphytic bryophytes on Z. abelicea growing at the same study site on Mt. Kedros. ...
Zelkova abelicea is an endemic tree species growing in several localities in the mountainous regions of Crete, Greece. To date, the microarthropod species associated with this tree species have not been identified. Since Z. abelicea populations are isolated and fragmented, it was hypothesized that the characteristics of microarthropod assemblages, particularly in the case of springtails (Collembola), would vary and differ among localities. Moreover, rare microarthropod species that colonize microhabitats not included in previous studies on Zelkova trees were expected to be recorded. Samples
were collected from the bark and twigs of Z. abelicea at eight localities in all main mountain ranges. Among the collected material, Collembola were the most numerous (10,285), followed by Acari (2237) and representatives of Psocoptera (422). The obtained material and statistical analyses showed that the arthropod assemblages differed considerably at each experimental site, with the most distinct assemblage characteristics observed at the Gerakari site on Mt. Kedros in central Crete. The most numerous specimens were species of Collembola: Xenylla maritima (3844), Xenylla sp. 2 (maritima
complex) (3364) and Xenylla sp. 1 (maritima complex) (2631). A total of 33 Collembola species were recorded, of which 19 had not been previously reported in Crete. Among them, 11 species were likely new to science and will be the subject of separate taxonomic studies.
Christensen, S. N. 2023. Contribution to the knowledge of the lichen biota of Pinus nigra stands in Greece. – Herzogia 36: 428 – 444.
One hundred and seven epiphytic taxa, 4 epigeic taxa and 8 epilithic taxa are recorded from 17 Pinus nigra stands across its distribution area in Greece. Generally, the lichen biota is referable to a Pseudevernion community with nitrophytic elements. Caloplaca xerothermica, Lecidella subviridis and Parmelia barrenoae are new to Greece. Six species are new to Epiros, 5 species are new to Makedonia and 5 species are new to Peloponnisos. Elixia cretica is reported for the first time outside its type locality. The new combination Caloplace xerothermica (Vondrák, Arup & I.V.Frolov) S.N.Christensen is made. Studies on epiphytic lichens on Pinus nigra in Greece and neighbouring countries are discussed.
Christensen, S. N. 2023. Beiträge zum Kenntnis der Flechtenbiota griechischer Pinus nigraBestände. – Herzogia 36: 428 – 444.
Einhundertsieben epiphytische Taxa, vier epigäische Taxa und acht epilithische Taxa wurden aus 17 Pinus nigraBeständen im gesamten Verbreitungsgebiet in Griechenland erfasst. Im Allgemeinen sind die Flechtenbiota einer Pseudevernion-Gemeinschaft mit nitrophischen Elementen zuzuordnen. Caloplaca xerothermica, Lecidella subviridis und Parmelia barrenoae sind neu für Griechenland. Sechs Arten sind neu für Epiros, 5 Arten sind neu für Makedonien und 5 Arten sind neu für Peloponnisos. Elixia cretica wird zum ersten Mal außerhalb ihrer Typuslokalität gemeldet. Die neue Kombination Caloplaca xerothermica (Vondrák, Arup & I.V.Frolov) S.N.Christensen wird hergestellt. Es werden Studien zu epiphytischen Flechten an Pinus nigra in Griechenland und den Nachbarländern diskutiert.
Microrefugia are often located within topographically complex regions where stable environmental conditions prevail. Most of the studies concerning the distributions of climate change-sensitive species have emphasized the dominance of cold air pooling over other environmental factors, such as resource availability. There is a shortage of information on the relationships among topography-related microsite diversity, microclimate, resource availability, and species composition in microrefugia. To fill this knowledge gap, we studied the effects of microclimatic conditions and soil resources on plant species occurrence within and adjacent to 30 large topographic depressions (i.e., dolines) in two distant karst regions. Our results showed that both microclimate and soil resource availability may play a key role in maintaining climate change-sensitive species and biodiversity in dolines; therefore, they may simultaneously act as climate and resource microrefugia. Establishing climate-smart conservation priorities and strategies is required to maintain or increase the refugial capacity of such safe havens.
Trees are the most important landscape architects of our planet, not only in forests but also in countless other ecosystems, including human-fabricated habitats. Due to their significance in the majority of terrestrial ecosystems, trees play an important role in maintaining biodiversity and providing food and habitat for countless microorganisms, fungi, climbers, invertebrates, and vertebrates. Trees are also indispensable for the development of human societies and are important for our survival today and in the future. Trees therefore have an inestimable scientific, economic, social, cultural, and aesthetic value. In addition, they were and are playing an essential role in myths, rituals, and cultures of nearly all indigenous and modern societies. Despite these facts, the protection of trees is insufficient, both globally due to climate change and deforestation, but also locally, for example in the big cities through deterioration of soils or improper care. In industrialized countries, only recently has the need for targeted protection efforts for tree species or even for individual trees been recognized. Our review starts with the differentiation and definitions of forests and trees. Furthermore, we present the main categories and subcategories of trees, each of them
possessing different functions in their ecosystems and for human societies and thus needing specific legal protection measures. The second part of our review presents the most important tools for improving the protection of trees. On the one hand, there exist a series of international initiatives, conventions, and agreements, and on the other hand, there are numerous legal tools, such as red lists, lists of protected species, and legislation for the protection of monument and habitat trees. The main challenge of the 21st century is to find a solution to make the development and growth of modern human societies compatible with the protection of natural resources such as forests. The large number of tree species, as well as the large proportion of threatened tree species, makes this problem even larger. Finally, the most recent and controversial approach of attributing trees the rights as legal persons is discussed.
