Epilithic lichens and their morphological adaptations to the conditions of the White and Barents Seas coast (Russian Arctic)

• Main Author: Sonina, Anzhella V.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Masaryk Univerzity 2012
• Subjects: Epilithic lichens; morphological adaptations; physiological adaptations; usnic acid; Arctic; Barents Sea; White Sea; Murmansk
• Online Access: http://journals.muni.cz/CPR/article/view/12820

The main aim of our work was to investigate the biodiversity of coastal lichens, conditions of lichen cover formation, and study the structural and functional adaptations of Lecanora intricata (Ach.) Ach. and L. polytropa (Ehrh. ex Hoffm.) Rabenh. The investigation was carried out during 2008-2012 on cliffs both along the Murmansk (the Barents Sea) coast and the southern and western shores of the White Sea. For the evaluation of species composition, and ecotopic coenotical features of epilithic lichen growing on cliffs, the geobotanical methods have been used. In addition, the anatomical, morphological and biochemical studies of Lecanora intricata and L. polytropa have been made. 91 species have been included in the total list of lichens on the White Sea coast. On the Murmask coast of the Barents Sea, 36 lichen species had revealed. On the coastal territory, the epilithic lichens inhabit the upper littoral and supralittoral zone. The lichen cover is formed by two interacting factors: the water factor (sea) and the terrestrial vegetation. Four lichen zones were distinguished in the all studying territories. They differed by the lichen species composition and effect of the sea. The first lichen’s zone is the intrazonal structure in the complex coastal lichen cover. In Lecanora polytropa and L. intricata, structural and functional features of lichens for adaptation to unstable coastal conditions were identified. The crustose biomorphs were better adapted to temperature and degree of hydration of thalli. Formation of the smallest ascospores is reproductive strategy of epilithic lichens in extreme habitats. High content of usnic acid in the studied lichen thalli allows them to exist in the open areas exposed to solar radiation and provides the biotic regulation that affects the structure of lichen cover. Optimal ratio of algal to fungal components in the thalli of these species is necessary to maintain their life in extreme environments.