Only those plants that are able to withstand the harshness of its natural and climatic conditions dominate in the tundra. Tundra landscapes are swampy, peaty and rocky. Bushes do not invade here. Their distribution area does not go beyond the border of taiga areas. The northern expanses are covered with dwarf tundra plants creeping along the ground: polar willow, blueberries, lingonberries and other elfins.
The fauna here is formed mostly by mosses, lichens, sedges and fungi. Short grasses now and then interrupt the moss-lichen pillows. Trees and shrubs are represented by small forms. There are only polar willow and dwarf birch. Tiny trees sometimes break through the closed turf, sometimes they grow completely.
Polar willow - dwarf shrub
A unique representative of flowering plants is the polar willow. Although it is excessively small, it still refers to tundra shrubs, and not grasses. tiny plantforced, due to natural conditions, to become like not a shrub tree, but an elfin creeping along the ground.
On thin tree-like stalks, the minimum number of durable leaves are strengthened, which do not crumble, like other willows in autumn. They remain green even under the snow cover. The plant has two more names - dwarf willow and arctic. The polar willow in the tundra is not alone. Along with it, there are representatives of the Magadan, Yenisei, grassy and several other dwarf breeds.
Nutritional value of the polar willow
Willow leaves are excellent food for reindeer. They, in order to get enough in winter, dig them out from under the snow. In winter, its shoots, buds and bark are not neglected by hares, partridges and rodents.
Arctic shrub leaves are edible. Northern peoples store the plant for future use and cook quite exotic food from it. They will twist the deer's stomachs and fill them with boiled leaves and the liquid in which the plant was boiled. The Chukchi feed on a mixture of willow leaves and deer blood. The Eskimos season them with seal fat and blood. In addition, surrogate tea is prepared from the leaves.
Biological Description
Dwarf shrub of herbaceous appearance has miniature tree-like climbing trunks. You look at the pictures, which depict a polar willow, and you wonder how bizarre nature is. Tiny trunks are formed by tiny underground branches. They are short compared to ordinary trees. Their length does not exceed 3-5centimeters.
On the creeping, rooting yellow twigs, there are a few tiny leaves that stick out over the turf. Lanceolate stipules, although inherent in the plant, are rare. They prefer to be absent. The leaves have rounded outlines, broadly obovate. Sometimes they are kidney-shaped and only occasionally elliptical-broadly lanceolate. Their tops are roundish.
The leaves are often notched in shape. Their base is outlined either by rounded or heart-shaped, and very rarely wedge-shaped lines. This is what the polar willow looks like - an unusual tundra tree. Green leaves with entire sides have a matte top and a slightly shiny bottom. The length of the bare petioles is only 1 centimeter. The length of the leaves, strung on tiny petioles, does not exceed 2.5 cm, and the width is not more than 1.3 cm.
The terminal flower earrings are usually oblong or ovoid in shape. The number of miniature flowers in them varies from 3 pieces to 17. The polar willow is also equipped with bracts. Their description is as follows: dark brown scales with ovoid (sometimes reversely ovoid) rounded, concave forms have jagged edges.
There are two naked free stamens. They have a dark anther and an oblong-ovate narrowed nectary. The ovaries are conical, light-felt shades at first, grow bald over time, repainting in greenish or purple tones. Bipartite divergent stigmas have an oblong-linear nectary.
Of coursesuch trifles are not always possible to consider in nature, and even more so in the photo. The polar willow, like many other plants, is thoroughly studied by biologists in laboratories.
Arctic willow range
The dominance of the hardy plant begins in the polar deserts that cover the Arctic islands and extends to the northern environs of the Putorana Plateau. The range of the dwarf shrub captured the Scandinavian, East Siberian, Chukchi and Kamchatka lands in the tundra. It stretches across the expanses of the islands of Jan Mayen and Svalbard.
In an endless struggle with the negative conditions of the harsh Arctic, the tree has found reliable ways to survive in the inhospitable northern places. During the ice age, when the ruthless onslaught of the approaching glaciation became unbearable, the polar willow was forced to retreat to the south.
The retreating glacier allowed her to recapture her beloved northern territories. It firmly entrenched itself within its former borders, settling in the region of Novaya Zemlya and the Commander Islands. The incessant Arctic thaw contributes to the stubborn advancement of shrubs to the borders of the Far North. It penetrates the tundra and the Arctic zone with great speed (for dwarf plants). Its range is increasing by a kilometer every year!
Soils
The tree has a wide ecological amplitude. They are chosen by soils of various compositions. It avoids except limestones, however, it is sometimes found on them. Feels great on grassy, gravelly, clayey soils, characteristic of the arctic and alpine tundra. Shrubundemanding to soil moisture. There is no polar willow in the tundra in areas that are too dry or too wet.
She is indifferent to the richness of the soil. True, it does not want to grow on high peat mounds of polytrich, dotted with swampy areas. They have a depleted acidic substrate, which is not at all like a dwarf shrub. But on zonal tundra gley soils, it grows everywhere. The plant neglects little snowy places. He is attracted by nival corners with good snow cover.
Ecosystems with polar willow
Wherever you look, almost everywhere, with the exception of the northern zones, the shrub has adapted to the moss-lichen surfaces. Such thalli are an amazing sight. Their caps of rich greens, yellows, oranges, reds and other colors form fabulously beautiful landscapes. Willow stems are always immersed in mossy turf, and the leaves, on the contrary, rise above the surfaces of picturesque hillocks.
The tree is tied to pebbles and block collapses, which is clearly shown in the photos. The polar willow in the tundra is hidden in small crevices formed by stones. Between the pebbles, she finds mechanical protection and mostly humus soils.
However, of the numerous moss-lichen phytocenoses, the shrub prefers loose turf. Precisely those surfaces that are formed by hypnum amphipod mosses, liverwort and similar vegetation.
Ecological nichespolar willow
The mountain ruins of Putorana became the habitat of the dwarf shrub. He found shelter among the miniature crevices and fissures that cut through the Kotuy and Anabar plateaus. Its thickets covered snow-covered niches that strewn the bald belt. They did not fail to crawl into the forests with damp moss thalli, which founded the colorful northern ecosystem.
And what does the polar willow look like in mountain snowy valleys? Here it forms massive thickets. The beds of snowfields are completely covered with it, and the ice is in a dense environment of small leaves sticking out. And at the same time, the plant is inactive in the open spaces of the plain forest-tundra and southern tundra.
It is scattered along the nival ravines, at the foot of the northern slopes. Dwarf willow thickets sprawled over the lakeside mossy shrubs. They covered the sides of deeply cut streams.
Their activity is increasing in typical tundra. The abundance of willow growth is noted in the biocenoses of moraine landscapes. Where on the plains there are accumulations of stony debris left over from the movement of glaciers. In alluvial and alluvial zones, the role of shrubs is reduced.
It becomes interesting how the polar willow, the photo of which you are looking at, looks like in spotted tundra, along the sides of valley streams, and where watersheds lay and delle complexes formed. In places with willow-moss-grass thalli.
Dominance of willow bushes in the tundra
In the presence of polar willows, the vegetation of the arctic tundra is formed. Moreover, the dwarf shrub is activelydominates in most upland phytocenoses. In particular, it prevails in willow-moss-grass communities. In addition, its predominance is noted in the Byrranga mountain ranges.
Abundant thickets of dwarf willow have mastered the moss tundra. They clogged the crevices of gravelly tundra. Their havens are delle complexes, plumes enriched with humus, bulk and little snowy places. The willow covers the valley polygonal swamps all over.
Willow in the mountains
With willow bushes that settled in the cracks between the stones, a spectacular photo is obtained. The polar willow is not uncommon in mountain landscapes; it is part of all kinds of biotopes, capturing vast territories. Its leaves stubbornly bristle all over the mountain belt, making their way to the top. Here she is not attracted only by exposed screes and unturfed gravelly areas.
Climbing to a height of 300-400 meters, it displaces the dryad, turning into the dominant edificator of tundra mountain phytocenoses that develop in the upper tier. In addition, in places of mountain pebbles and sands, it is able to replace the willow, which is unable to go deep into the steeps. The blocky ruins of the foothills and uplands of Byrranga are overgrown with hybrids of the polar willow.
