vegetation of tundra and forest tundra, its forms, methods of breeding plants adapted to survive largely depend on the features that characterize these zones.
Geographical location
Location tundra falls on subarctic zones of the Earth.On the mainland of Eurasia, it stretches along the coast of the Arctic Ocean in the tens of thousands of kilometers.The north coast of mainland North America also occupied by tundra.The length of the area from north to south at an average of about 500 kilometers.In addition, the Tundra takes some islands near Antarctica.In the mountains, where the expressed high-altitude zone, formed mountain tundra.Taking into account all areas where there is a zone, it calculated the total area on the planet.It is about 3 million km2.
forest tundra - a zone where small patches of vegetation is tundra and taiga vegetation.Forest-tundra stretches from west to east in the south of the tundra of Eurasia and North America.The length of the strip from north to south varies in the range from 30 to 400 kilometers.On the southern borders of his passes in the forest-tundra zone.
climatic conditions affecting the growth of plants
climate of tundra and forest tundra is very severe.Winter lasts from 6 to 8 months of the year.During all this time kept constant snow cover, air temperature sometimes drops to 50 degrees below zero.The polar night lasts about two months.Almost never subside strong cold winds, snow storms.
summer in the tundra are short and cool.Chance of freezing and precipitation in the form of snow.Despite the polar day, the ground does not get much heat as the sun is low on the horizon, and sends back to Earth scattered rays.To survive in such conditions, tundra vegetation must adapt.
Effect of permafrost in the species composition of vegetation
In the warm season in the tundra soil thaws only to a depth of no more than 50 centimeters.Next comes a layer of permafrost.This factor is one of the most decisive in the resettlement of plants in the tundra zone.This factor affects their diversity.
permafrost has a significant impact on the terrain.Freezing and thawing species leads to their deformation.As a result of these forms appear heaving surface like mounds.Their height is not more than two meters above sea level, but the appearance of these forms also affect the tundra vegetation, its settlement in a specific territory.
Effect of soil on species diversity of vegetation
In the area of tundra and forest tundra there is a high water-logged soil.It is especially noticeable during the snowmelt.Water can not penetrate deep into the presence of permafrost.Evaporation is not too great intensity due to the low temperature air.For these reasons, melt water and the precipitate accumulated on the surface to form large and small marshes.
High waterlogging, the presence of permafrost, the prevalence of low temperatures impede the flow of chemical and biological processes in the soil.It contains little humus accumulates iron oxide.Tundra-gley soils are suitable for growing only a single species.But tundra vegetation adapted to such conditions of life.The man, who visited these parts in flowering plants remain an indelible impression for years to come - so beautiful and attractive flowering tundra!
In the forest a natural layer of fertile land is also malomoschen.The soil is poor in nutrients, it is characterized by high acidity.With the domestication of land in the soil make a large amount of mineral and organic fertilizers.In treated areas the forest-tundra are found more variety of types of grasses, trees and shrubs.
types
vegetation tundra and forest tundra largely depends on the type of natural areas.Their landscapes at first glance seem to be monotonous.
tussock tundra and bumpy occupy the largest territory.Among swamps turf plant forms mounds and mounds, on which many species of plants take root.A special type of tundra - polygonal.Here you can watch landforms in the form of large polygons, which are divided into depressions and frost cracks.
There are other approaches to the classification of such natural areas as tundra.What vegetation predominates in a particular area, such will be the type of tundra.For example, moss-lichen tundra up areas covered with different kinds of mosses and lichens.There are also shrub tundra, where thickets of polar willow, cedar, bushy alder.
Plants
As mentioned earlier, the vegetation of tundra and forest tundra had to adapt to the harsh climatic conditions of the subarctic zone of the Earth.Otherwise her life and development would be impossible here.
adaptation of plants tundra and forest tundra is expressed as follows.Most of the fauna are perennials.Annual plants during the short duration of the summer would be unable to complete its life cycle.Only a small part of the plant is propagated by seeds.The basic way to prolong life - vegetative.
Stunting tundra plants allows them to hold during strong winds.This also contributes to creeping shoots character and their ability to intertwine with each other, forming a kind of soft cushions.In winter, all the parts of the plants are covered with snow.It saves them from severe frosts.Most plants tundra and forest tundra on the leaves have a waxy coating that helps to moderate the evaporation of moisture from the surface.
tundra vegetation, pictures of certain types which are available in the article presented frost perennial grasses: sedge, dominant in the lowlands and swamps, buttercup, cotton grass, dandelion, poppy seeds.Because trees grow dwarf birch, polar willow, bushy alder.These tree species in the forest can already reach a height of three meters and more.Among the shrubs are widespread blueberries, cloudberries, blueberries, cranberries.At higher elevations take root mosses and lichens, many of which are the main type of food found in these places the animals.
forest tundra and taiga
tundra and taiga vegetation is very different from each other.Forest-tundra is a transition zone between them.On the territory of the forest-tundra among treeless islands of space can be found thickets of spruce, birch, larch and other trees.
forest tundra zone is unique because it is found in its territory vegetation tundra and taiga vegetation, which is increasingly becoming a noticeable progress in the south.Forest areas, consisting of individual trees and shrubs, creating the most favorable conditions for the growth of herbaceous vegetation.Because of trees and shrubs is reduced wind speed is delayed more snow, which covers the plants, saving them from freezing.
Learning subarctic vegetation belt
vegetation cover of tundra and forest tundra has not been studied fully.Systematic scientific description of species growing here began only in the middle of the last century.
to continue this work and today there are special expedition.In the course of these scientists are also trying to determine how the vegetation on the tundra and forest tundra affect animals living in these areas.They want answers to questions about whether the changes of plant species diversity in areas that are protected by the presence of certain species of animals, how long it takes to fully restore the destroyed vegetation.While researchers found no answers to all questions relating to the balance of nature in the area of the subarctic zone of the planet.
Fauna
Nature tundra and forest tundra is very vulnerable.On restoration of soil, vegetation requires more than a decade, and in some cases centuries.
Man has long been understood that he is having a devastating impact on the nature of tundra and forest tundra.Trying to atone, people have created a number of nature reserves, national parks, game reserves.They are located on the territory of Russia and other countries.
