Vorkommen und Gefährdung der Flechten Deutschlands

Litterski, B., Schiefelbein, U. & Wirth, V. 2019. Lichen occurrence and threat status in Germany. – Herzogia 32: 19–40. Lichens are often given insufficient consideration in nature conservation, even though they are highly threatened. Here, we analyze the lichen flora of Germany with an emphasis on their occurrence in habitat groups. We distinguished the following habitat groups: high mountain range above the tree line, open rock habitats in highlands, coasts, waters, peatlands, forests (summarized to natural landscape), semi-cultivated land, cultivated land and settlement area (summarized to cultivated landscape). The occurrence and threat status of lichen species were analyzed with respect to their habitats, substrates and distribution. The main habitat of 75 % of the lichen species in Germany is in natural landscapes. The number of lichens in forests is high (656 species = 32 % of the lichen flora) and open rock habitats in mountainous regions are also important for lichens (454 species = 22 % of the lichen flora, without alpine vegetation). The proportion of extinct and threatened lichen species in forests (56 % of 656 species) is much higher than the proportion of extinct and threatened higher plants in forests (14 % of 851 species). In dry semi-cultivated land, the threat status of both groups is high (lichens: 52 % of 288 species, higher plants: 42 % of 696 species are extinct or endangered). In alpine vegetation, similar numbers of lichens of and higher plants occur, but the proportion of extinct and threatened lichens (29 % of 294 species) is higher than those of higher plants (11 % of 302 species). In contrast to higher plants, various substrate types and special habitat sites and structures are important for lichens. We found a high threat status of epiphytic and terricolous lichens, with the proportion of extinct and threatened lichens at about 60 % in each case. Among the endangered lichens of the distribution type V (med–temp.subatl; 67 % of 251 species are extinct or endangered), there are many species dependent on old-growth forests and with limited dispersal ability. The high proportion of threatened lichen species of distribution type I (temp/mo-alp-arkt) in Germany (46 % of 459 species) is likely a product of multiple factors, including atmospheric emissions, land use change and climate change. Due to their specific properties, habitat requirements and threats against them, lichens of both natural and cultural landscapes need more attention in nature conservation work.