The northern forest or taïga (of the Russian Тайга) is a Biome and a vegetable Formation characterized by its boreal Forêt S of Conifère S, scientifically called Aciculisylvae .

It is a biogeographic Région Scandinavian subarctic in which the Flore is mainly made up of Sapin S and others Conifère S with persistent sheets, which are adapted to the cold Climat. Taïga is the most septentrional zone of still wooded planet.

The Marsh and their associated plants are also common in this zone, which covers the majority of the interior grounds of the Canada, of the Scandinavia and the north of the Russia. With the Canada, the “Canadian Northern forest” indicates the northern edge of the boreal forest coniférienne and not simply the biome.

It is about the one of the principal reserves of Oxygène of planet.

Situation

The taïga or northern forest draws in fact broad band under the Toundra of the artic regions. Taïga appears in the Northern Hemisphere like a vast circumpolar ring, almost continuous on 50 km (60 km in Eurasia, 35 in North America), simply stopped by the Bering Strait and by the Atlantic Ocean. This zone thus covers the majority of the interior grounds of the Canada, the Scandinavia and the north of the Russia.

Climate

The ecosystem S of taïga know average annual temperatures being located between - 1°C and 0°C. The Température S averages of summer are located between 10 and 15°C, but the minimal averages of winter can go down below -30°C. The Precipitation S, regular throughout the year, are about 4 to 8 mm per annum. Time alternates Brouillard, Neige and Pluie. One can thus speak about continental Climat rather varientes.

Ground

The ground of Acid taïga east very , because of the climate and the vegetation, it is called Podzol or Podzosol.

Under a cold Climate, the organic matters (sheets, wood) resulting from the plants break up slowly into releasing from the organic acids. These acids react with some bases remaining in the ground (Calcaire or other) and involve them towards the tablecloths and rivers by the phenomenon of the Lessivage. Result, the grounds are at the same time low in biogenic salts useful for the trees and very acids.

This acid ground is also found in the moderated areas with Conifère S, this pedogenesis partly due to persistent (in particular large conifers the such spruce S and pine S).

Vegetation

The most widespread trees in taïga are Conifère S adapted to the Froid, like the larches, the spruces, the pine S and the fir trees. Their conical form makes slip snow; their covered needles of a waxy coating protect them from freezing; their color dark green absorbs the weak radiations of the sun and supports photosynthesis. One also finds leafy trees, in particular the birches, the willows, the poplars and the sorbs.

There are also Marais, with all the vegetation which are associated for them.

Fauna

It is the zone more in the North in which the species which need some trees can survive. A considerable number of Bird X such as the Siberian Thrush (or obscure thrush ), the white Thrush and the Grive with dark throat migrate towards this habitat to benefit from the long days of summer and abundant food in Insecte S during this season.

Some birds Carnivorous S and certain large birds Omnivore S which can find there preys alive or carcasses which are also present in this zone during the Hiver. Among those, the cross nozzle, the eagle gilded and the Harrier.

Relatively few Mammifère S can face the hard winters. Among those which can it, one finds the dash, the lynx, the Loup, the beaver, the Lièvre of snows, the Lemming, the caribou and several family members of the Mustélidé S such as the Glouton and the Martre of the pines.

Damage related to the human activities

Because of a very fragile nature, the attacks of anthropic origin on the zones of taïga remain visible very a long time. It is necessary several centuries so that the trees push back until their adult height.

See too

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