Arctic Subregion

Arctic Subregion

 

a floristic and zoogeographic sub-region of the Holarctic region. The arctic subregion occupies the tundra zone of Europe, Asia, and North America, as well as all the islands of the high arctic. The subregion is bounded on the south by a sparse forest zone in which there are abundant upland marshes rather than spotted tundra.

Arctic floristic subregion. The arctic floristic subregion is characterized by the absence of forests. Flora is represented primarily by mosses and lichens; about 500 species of shrubs and grasses are known. Arctic flora consists of the following basic groups: the arctic species, endemic to the arctic subregion—the most ancient, so-called eoarctic (ancient arctic) pre-Ice Age and early Ice Age flora (for example, Dupontia, certain varieties of whitlow grass, Astralagus aboriginorum, cassiope, and diapensia); the arctic-Alpine species, found in the arctic subregion and in the high-mountain flora of the Alps, the Altai, the Western and Eastern Saian, and other mountain systems (dryas and some varieties of saxifrage and gentian); the hypoarctic species, also found in forest tundra and adjacent regions of the forest zone (the dwarf arctic birch, cloudberry, wild rosemary, and crowberry); the boreal species, characteristic of the forest zone but spreading into the arctic subregion (many forest mosses, whortleberry, cowberry, and others); the arctic-steppe species (related to the inhabitants of the cold steppes), which penetrated to the arctic subregion in the geological past (Oxytropis, Lychnis sibirica, and Cerastium maximum); and the marine halophytes, which are characteristic of salty seashores (for example, Ammodenia peploides, Pucciniella phryganoides, and Carex sub-spathacea).

Three main characteristics are inherent in the flora of the arctic subregion: distribution of species around the pole (for example, Oxyria digyna, Saxifraga caespitosa, and S. cernua); a decrease in the number of species from south to north (the Bol’shezemel’skaia tundra has 342 species, Novaia Zemlia has 200, and Franz Josef Land has 37); and a distribution of species in an easterly and westerly direction from Taimyr and the island of Yakutia—some species are found east of Taimyr, and others gravitate to the Atlantic shores of the arctic. A gradual decrease in the number of species is observed east and west of these centers.

The flora of the arctic subregion includes a number of economically valuable species. The shrubs are the main source of fuel for the local population. Many species of plants are important as food (for example, the whortleberry, cloudberry, and arctic bramble) or medicine (scurvy grass—an antiscorbutic); the cereal grasses, sedge, and mixed grass are important as fodder. The tundra pasture plant, reindeer moss, is the basic fodder of the reindeer.

V. S. GOVORUKHIN

Arctic zoogeographic subregion. In the arctic zoogeographic subregion, living conditions are severe and extreme and are unfavorable for most of the animals on the earth. Only a few species find their optimal conditions here, and therefore the species of fauna are few in number. The number of individuals is also usually small, with the exception of a few places with more favorable conditions (such as bodies of water). The lengthy, cold, and dark winter, the brief, cold summer, the lack of forests, and the strong winds are among the conditions unfavorable to life. For the duration of the winter, almost all life dies away in the arctic subregion: all birds except a few species fly away, the large mammals migrate to the forest zone, and the small mammals hibernate or remain burrowed under the snow. Summer living conditions are favorable for the specialized species of the arctic subregion chiefly because of the long daylight hours, which compensate for the brevity of the warm period.

A number of the characteristic mammals of the arctic subregion are found throughout the entire territory (circumpolar distribution): the arctic fox, the reindeer, and small rodents such as the lemming (both common and arctic). Certain species of common vole, northern redbacked vole, suslik, and marmot are found only in certain parts of the arctic subregion, either in Eurasia or in America. The musk ox is found only in America. Some species that are primarily distributed farther south, such as the blue hare, wolf, and wolverine, are found in the arctic subregion.

There are very few purely terrestrial birds—the rock ptarmigan and common partridge, shore lark, snow bunting, Lapland bunting, tundra redpoll, and several other species of the order Passeriformes, the snowy owl, and the rough-legged buzzard. There are quite a few species living near inland waters and to some extent on seashores—for example, of the order Charadriiformes, the sandpipers (including more than ten species: the knot, pygmy sparrow, Baird’s sandpiper, purple sandpiper, and others), as well as the sanderling, broad-billed sandpiper, stilted sandpiper, buff-breasted sandpiper, spoonbill, phalaropes, and plovers. There are a number of ducks (eiders, the long-tailed duck, and scaup), geese (the white-fronted goose, lesser white-fronted goose, and snow goose), brant geese (barnacle goose, redbreasted goose, and Canada goose), and Bewick’s swan. There are no amphibians or reptiles in the arctic sub-region.

Like the mammals, the birds have ranges covering the entire arctic subregion or only parts of it; a considerable number of species occupy only northeastern Siberia and Alaska, where the ancient center of species formation in the arctic and cold temperate zone is located.

A considerable number of species of seagulls, terns, guillemots, and birds of the order Tubinares (Procellariiformes) inhabit the arctic subregion. There are seals, polar bears, and some other mammals, but their life and distribution are tied to the sea and depend on the conditions of life in the sea; they are basically members of sea fauna complexes.

V. G. GEPTNER

REFERENCES

Gorodkov, B. N. Rastitel’ nost’ tundrovoi zony SSSR. Moscow-Leningrad, 1935.
Vul’f, E. V. Istoricheskaia geografiia rastenii. Moscow-Leningrad, 1944.
Geptner, V. G. Obshchaia zoogeografiia. Moscow-Leningrad, 1936.
Bobrinskii, N. A., and N. A. Gladkov. Geografiia zhivotnykh, 2nd ed. Moscow, 1961.
Tolmachev, A. I. Arkticheskaia flora SSSR, issues 1–2. Moscow-Leningrad, 1960–64.
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