Holarctic

The Holarctic is a biogeographic region and provides both a floral kingdom as well as a Faunenreich; they include most of the northern hemisphere of the earth and is the largest of the regions. The southern boundary of the Holarctic runs in northern Mexico (but ranges in the highlands further to the south than on the coast ), includes the Cape Verde islands, runs along the northern edge of the Sahara and the Arabian Peninsula, along the Himalayas to southern China, Taiwan excludes and Japan one.

Floral kingdom

Characteristic representatives of the Holarctic are the (Pinaceae ), Birch family ( Betulaceae ), Beech family ( Fagaceae ), willow family ( Salicaceae ) and the majority of the buttercup family ( Ranunculaceae ) and Rose family ( Rosaceae ). In addition, here also have the (Brassicaceae ), Pink Family ( Caryophyllaceae ), the Rushes ( Juncaceae ) and the genus of sedges ( Carex ) their focus.

A certain degree of differentiation within the Flore Empire resulted from the ice ages of the Pleistocene: In Europe, a large part of Pliozänflora died from, so the flora of Europe is impoverished today. Some families like the magnolia plants, Hamamelidaceae and Styracaceae therefore come only in North America and Asia, but not in Europe.

The floral kingdom of the Holarctic region is divided into the Arctic, Boreal, Atlantic, südeurosibirische, Mediterranean and Irano - Turanian regions Flore. The piles regions are determined by the occurring in the region taxonomic plant species:

Arctic - Main distribution in the treeless Arctic tundra, coniferous forest zone to the inside -reaching, even in the Alps, only a very short growing season with mean daily need below 10 ° C

Boreal - an essential part of the great coniferous forest zone, character tree is the spruce - Picea abies. Many of these Flore elements extend far into Central Europe and some subboreale species, such as Pinus sylvestris, even far to the south

Atlantic - a group of Flore elements which are strongly bound to the oceanic climate, partly in Central Europe, but hardly in Eastern Europe are represented

Eumitteleuropäische - mainly species from which the deciduous forest zone composed. It is Central European species in the strict sense, their distribution does not extend to Eastern Europe. Central European species in the broader sense, however, reach quite central Russia, but partially to the Urals

Mediterranean - here is geoelements which form the Mediterranean sclerophyllous zone. They are typical of areas with winter rainfall and a pronounced summer drought

Pontic - Types of treeless steppes of Eastern Europe, but in which, although the summers are hot, winters are contrary to the Mediterranean region much colder than in Central Europe (Walter 1986:38 ).

Südsibirische - these species have their main distribution point in the transition zones between the West Siberian steppes and the taiga

Turanian - Central Asia - South-East European species of the semi-desert in Central Europe rarely on saline soils and sometimes on seashores.

Faunenreich

The Faunenreich Holarctic is divided into two regions Nearctic (Greenland and North America) and Palaearctic. The boundary of the Faunenreichs extends further to the south, and here is partially a broad transition region defined to the other Faunenreichen. The limit in America is either drawn as in the floral kingdom (H. J. Müller) or a transition zone, which includes all of Central America and the Caribbean believed. In Africa, the boundary runs south of the Sahara, or the Sahara is considered as a transition region, the same applies to Arabia, where the southern edge of the Arabian Peninsula does not count that.

Characteristic mammals include moose ( Alcinae ), True deer ( Cervinae ), the lynx (Lynx ), the goats and sheep ( Caprinae ), nutria ( Castoridae ), the pikas ( Ochotonidae ), among the insectivores the moles ( Talpidae ) and shrews ( Soricidae ) and among the rodents, the Hüpfmäuse ( Zapodinae ) and voles ( Arvicolinae ). Typical bird families are the grouse ( Tetraoninae ), Alcidae ( alkene ) and waxwings ( Bombycillidae ). Among the insects, the butterfly families Hesperiidae, Lycaenidae, Noctuidae, Notodontidae, Nymphalidae, Pieridae and Sphingidae.

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