Distribution and dispersal ecology of Lobaria pulmonaria in the largest primeval beech forest of Europe

Abstract

Occupancy and density of the epiphytic lichen L. pulmonaria were studied in the mountains of Uholka-Shyrokyi Luh (Ukraine), which include the largest primeval beech forest in Europe. The lichen occupancy was assessed on 314 plots laid out on a systematic grid. Additional data on population density were collected from 483 trees growing both, on and between these plots. The trees harbouring L. pulmonaria were distributed very sparsely within Uholka-Shyrokyi Luh, and occupy nearly 10 % of the studied perimeter. The generalized linear models showed that area of occupancy of L. pulmonaria was significantly influenced by altitude and canopy cover, whereas the species' density was explained by habitat types and slope exposition. Population density is higher at the timberline than in the interior forest or on lowland meadows. We found a bimodal altitudinal distribution of L. pulmonaria, with maxima below and above 900 m a.s.l., where it prefers forest stands with loose or scattered canopy. The preferred position of L. pulmonaria on host tree trunks depends on stand density and allows the species to get the necessary level of insolation also in shaded sites where it grows higher up on the trunk than in open stands. While L. pulmonaria occupied trees with various diameters, juvenile individuals are more frequent on small trees, but mature lichen individuals are predominantly found on trees of average or large sizes. Fertile individuals require specific environmental conditions, which are available at intermediate altitudes, related with sheltered light, and horizontal terraces on slopes with eastern exposition. In general, the primeval beech forest of Uholka-Shyrokyi Luh harbours a high percentage of juvenile thalli of L. pulmonaria, which lack vegetative propagules. Mature individuals have a Communicated by Pradeep Kumar Divakar.

Lobaria Pulmonaria (Ascomycota, Lobariaceae) In Bulgaria

“…During our field trips held in 2014 in the Rhodopes, the number of detected individuals varied from 50 thalli of juvenile lung lichen in bark of one old beech tree at an altitude of 1660 m in Mantaritsa Reserve (Figure 2), till 5 juvenile individuals in the region of Cigov Chark, noticed on bark of single beech tree and from 1-20 mature individuals seen at altitudes between 1350 and 1440 m, respectively. It is in agreement with conclusions recently published (28), stating that the presence of the lichen thalli, i.e. the occupation of the trees by the lung lichen, not only depends on the age of trees and air humidity, but also is primaly reflected by canopy cover and the altitude ranges above sea level.…”

Microclimatic differentiation of gene pools in theLobaria pulmonariasymbiosis in a primeval forest landscape

“…The altitudinal distribution of L. pulmonaria showed a clear bimodal pattern in the primeval landscape we studied (Nadyeina et al . ). Altitude also explains the diversity and composition of epiphytic lichens (Dymytrova et al .…”

“…We have showed recently that L. pulmonaria prefers relatively open stands in the forest landscape at higher altitudes and survives in the closed canopy of lowland valley growing high on tree trunks to receive the necessary level of insolation (Nadyeina et al . ). Our genetic analyses further revealed that different types of habitats, related to altitude, were colonized by different gene pools.…”

“…The bimodal distribution of L. pulmonaria (Nadyeina et al . ) and its gene pools (Fig. ) indicates that habitats are partitioned within the relatively homogeneous beech forest stands.…”

“…The height of the lichen thallus on a trunk is related to the degree of canopy openness, with optimum light availability higher up on the tree trunks under the dense forest canopies in lowland floodplains (Nadyeina et al . ).…”