Distribution factors of the epiphytic lichen Lobaria pulmonaria (L.) Hoffm. at local and regional spatial scales in the Caucasus: combining species distribution modelling and ecological niche theory

Pshegusov R., Khanov Z. & Chadaeva V.
17: 120–131
For the rare epiphytic lichen Lobaria pulmonaria (L.) Hoffm., there is a lack of data on ecological niche parameters and distribution factors in the Caucasus, which are necessary to develop an effective system of the species preservation during forest management. The aim of this study was to identify the influence of abiotic, biotic and movement factors on the potential distribution of Lobaria pulmonaria in the Caucasus forests, depending on the spatial scale. We combined species distribution modelling and ecological niche theory based on the BAM (Biotic-Abiotic-Movement) concept. A total of 174 occurrence data were retained in the modelling using Maxent ver. 3.4.3 in R. The distribution models of the main lichen phorophytes in the Caucasus (Pinus sylvestris L. and Fagus orientalis Lipsky) were used as biotic layers in models. The raster of distances from optimal sites, where the probability of the lichen occurrence remained above 0.5, was used as a movement-layer. Different abiotic predictors were significant in the lichen distribution in the Central Caucasus (terrain) and throughout the Caucasus (macroclimate). Interspecific relationships (lichen-phorophyte) were more significant at the local scale. The movement factor contributed most to the local model (80% of the contribution) and limited the lichen distribution to a radius of 20 m in the Central Caucasus and 30 m throughout the Caucasus. Field verification of the local model showed an 85.7% success rate of presence prediction with cutoff values of 0.8. The combination of SDM modelling and ecological niches theory is an effective method for studying the potential localisation and the ecological niches of epiphytic lichens. Keywords: Lobaria pulmonaria, Caucasus Forest, Species Distribution Modelling, Ecological Niche, Biotic-Abiotic-Movement Concept, Spatial Scale.
Sunday, 19 May 2024 18:07