In biogeography, a flora kingdom is a region that is characterized by its own flora . A large number of plant species occur only there . To distinguish the different floral kingdoms from each other, the terms Flore contrast and Flore gradient used: The occurrence of plant species is related to the removal of the studied areas. At the border of two flora kingdoms, the flora changes very strongly over short distances. This independent character of the flora is due to an independent genesis ( phylogenesis ) of the plant world and thus also includes plant species of high taxonomic rank ( families , genera ) that do not occur in any other area. These taxa are called the floral element of the respective plant-geographical unit.
Natural borders or barriers, such as high mountains , oceans or deserts , which prevent the plant families from spreading , often act as flora borders . If these limits are particularly old and effective, i.e. if an individual evolution has been able to take place longer , the contrast between the respective flora and others is all the more pronounced.
Differentiating between individual areas with their own flora is also possible on a small scale in many places. The floral kingdoms are the largest floral units, with a large-scale structure. They can be further subdivided into smaller units in terms of area. For this purpose, they are subdivided into floral regions, provinces, districts and districts.
These subdivisions according to flora are not to be confused with those which are based on vegetation , i.e. on characteristic plant formations . For example, the bromeliads (with the exception of a single species, Pitcairnia feliciana in West Africa) only occur in the flora of the Neotropics (in South America), but there in the vegetation zone of the evergreen rainforests, the humid forests, also in savannas and grasslands. They are absent in other tropical regions, although the vegetation is very similar: the flora borders prevent it from spreading to Africa and Asia.
Rich and characteristic floral elements
There are six continental flora kingdoms and one oceanic flora kingdom on earth :
- Holarctic - entire extra-tropical northern hemisphere: Apiaceae , Betulaceae , Fagaceae , Ranunculaceae , Rosaceae ; Acer , Carex , Pinus .
- Paleotropic - "Tropics of the old world": Africa south of the Sahara (without the southernmost tip), India, (Oceania). Didiereaceae , Dipterocarpaceae , Nepenthaceae , Pandanaceae ; Aloe , Nypa .
- Neotropic - "Tropics of the New World": South America (without the southernmost tip) and Central America. Bromeliaceae , Cactaceae , Cannaceae , Cyclanthaceae , Malpighiaceae ; Agave , Anthurium , Fuchsia , Passiflora .
- Australis - the continent of Australia, including Tasmania . Casuarinaceae , Goodeniaceae , Myoporaceae , Stylidiaceae , Xanthorrhoeaceae ; Styphelioideae (formerly Epacridaceae , according to more recent findings Ericaceae ); Acacia , Banksia , Eucalyptus , Brunonia .
- Antarctica - Antarctica , sub-Antarctic islands such as Kerguelen , southern tip of South America, southwest of New Zealand . Acaena , Azorella , Nothofagus .
- Capensis - includes only the Cape region in South West Africa. No palm trees, Aizoaceae , Bruniaceae ; Erica , Freesia , Pelargonium , Protea
- Oceanic flora kingdom - islands remote from the continents in the area of the world's oceans, especially in the Pacific. The oceanic flora kingdom is counted by some authors to the paleotropic.
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- Peter Sitte , Elmar Weiler , Joachim W. Kadereit , Andreas Bresinsky , Christian Körner : Textbook of botany for universities . Founded by Eduard Strasburger . 35th edition. Spektrum Akademischer Verlag, Heidelberg 2002, ISBN 3-8274-1010-X .
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