Pflanzengesellschaft des Jahres 2025: Flechten-Kiefernwald (Cladino-Pinetum sylvestris) [Plant Community of the Year 2025: Lichen pine forest (Cladino-Pinetum sylvestris)]

Author:
Horn K., von Brackel W., Ewald J., Heinken T., Becker T., Bergmeier E., Boch S., Härdtle W., Hölzel N., Lütt S., Remy D., Schneider S., Tischew S. & Fischer P.
Year:
2024
Journal:
Tuexenia
Pages:
44: 177–213
Url:
doi: 10.14471/2024.44.013
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One of the most endangered plant communities in Germany, and one that is on the verge of extinction, is the lichen pine forest (Cladino-Pinetum sylvestris, syn. Cladonio-Pinetum sylvestris). For this reason, it has been selected by the Floristisch-soziologische Arbeitsgemeinschaft as the “Plant Community of the Year 2025”. Lichen pine forests are unproductive, sparse and understorey-poor coniferous forest ecosystems, mainly in the planar and colline altitudinal zone. The soils are extremely nutrient-poor and acidic, usually very dry with a poorly developed humus layer. Lichen pine forests occur on outwash plains, moraines, dunes and valley sands, but also in mountainous areas with granite, quartzite or sandstone as parent rock. In Germany, this forest type is currently found only in small areas, mainly in sub-continental regions. Lichen pine forests occur mainly in the northeastern German inland lowlands from the Elbe valley in Lower Saxony eastward (Mecklenburg-Western Pomerania, Saxony-Anhalt, Brandenburg) as well as in Middle Franconia and Upper Palatinate (Bavaria). In addition to open woodlands with species of grey hair-grass swards (Corynephorion), there are lichen pine forests with almost no vascular plants and others with Vaccinium species, transitioning to the more widespread blueberry pine forests. Lichen pine forests represent a biodiversity hotspot in Central Europe for ground-dwelling fruticose lichens, especially reindeer lichens and other members of the genus Cladonia. They also host a variety of other lichens, bryophytes and macrofungi, and are important for faunal biodiversity. They represent an Annex I habitat type under the EU Habitats Directive (code 91T0). Lichen pine forests are at the beginning of natural forest development on immature soils on sand or quartz-rich rocks and have been strongly promoted by litter-raking and sod-cutting, and sometimes by grazing. They probably reached their greatest extent in the 19th and early 20th centuries. After the abandonment of the historical forest use, current stands are highly endangered, mainly by eutrophication due to natural succession and airborne nitrogen loads. Since the 1990s lichen pine forests in Germany have lost about 90 % of their former area. With an increased nutrient availability, competitive pleurocarpous mosses, sometimes dwarf shrubs and the wavy hair-grass, spread and displace the typical lichens and small-growing bryophytes. Other threats include land use (sand and stone mining, building areas), active forest conversion, a lack of morphodynamics and, in recent years, prolonged periods of heat and drought. Existing stands, some of which on the verge of extinction, must not only be protected from direct destruction, but also require active protection measures, similar to many open-land habitats. The restoration of lichen pine forests is only possible by removing the litter (together with the humus layer) and subsequently inoculating the raw soil with lichen fragments. First results from restoration projects in the Elbe valley of Lower Saxony and in Middle Franconia are presented. With these, we would like to encourage local and regional actors and conservationists to take appropriate action. In sand pits and quarries, refraining from recultivation measures can promote the formation of new lichen pine forests. Keywords: conservation management, eutrophication, historical land use, pine forest, plant community, restoration, species conservation, syntaxonomy.
Id:
37459
Submitter:
zpalice
Post_time:
Monday, 30 December 2024 19:14