In temperate latitudes, mainly in the forest and forest-tundra zones, such a variety of wetlands as sphagnum bogs is formed. The predominant vegetation on them is sphagnum moss, thanks to which they got their name.
Description
These are raised bogs, which are mainly formed in wet lowlands. From above, they are covered with a thick layer of sphagnum (white moss), which has a very high moisture capacity. It reproduces well, as a rule, only where there is a layer of humus.
Under the layer of this vegetation are acidic, poor in composition of water, with very little oxygen. Such conditions are absolutely unsuitable for the life of most living organisms, which include decay bacteria. Therefore, fallen trees, plant pollen, various organic substances do not decompose, remaining for thousands of years.
Varieties
Sphagnum swamps can be different in appearance. Often they have a convex shape, because the moss grows more vigorously closer to the center, where the mineralizationwater is especially small. On the periphery, the conditions for its reproduction are less favorable. Sometimes there are swamps of a flat shape. A distinction is also made between forested and non-forested.
The first are typical for the eastern part of Europe and Siberia, where there is a pronounced continental climate. Treeless sphagnum bogs are found in wetter climates, which are more common in the western regions of the European territory.
Origin of sphagnum bog
It has been established that the first swamps formed over 400 million years ago. The modern sphagnum peat bog is the result of a long evolution. After the ice age, water areas appeared, the main plants of which and peat-formers were grasses and mosses. The formation of peaty soils led to the formation of an acidic environment. As a result of the interaction of various geological and physical-geographical factors, land bogging or gradual overgrowth of water bodies occurred. Some of the swamps have become raised: their food is completely connected with precipitation.
Sphagnum raised bogs are filled with water and look like lenses. There are no mineral s alts in the precipitation, therefore, plants adapted to the lack of nutrition inhabit such swamps: mainly sphagnum mosses, grasses and small shrubs.
Peat formation
Dead plant particles that accumulate annually in the sphagnum bog form rather large layers of organic matter. Gradually they turn into peat. This process is influencedcertain conditions: excessive moisture, low temperatures and the almost complete absence of oxygen. The remains of all dead plants are not destroyed, retaining their shape and even pollen. By studying peat samples, scientists can determine how the climate in a given region has evolved, as well as how forests have changed.
Sphagnum bogs store huge reserves of peat, which serves as fuel for humans, so they are of great economic importance.
Sphagnum moss
Sphagnum moss plays the dominant role in the vegetation cover of raised bogs. It has a very peculiar structure. Reniform branches are located at the top of the stem, in its lower part there are whorls of long branches located horizontally. Leaves are made up of various cells, some of which perform certain vital functions and contain chlorophyll. Other cells are empty, colorless and larger, they are a receptacle for moisture, which they absorb like a sponge through the many holes in the shell. They occupy ¾ of the entire surface of the sheet. Due to them, one part of the sphagnum is able to absorb water. Moss gives a good annual growth, only in one year it grows by 6–8 cm.
Other sphagnum bog plants
On a moss carpet, only plants in which the rhizome is located vertically or slightly inclined can grow. These are mainly cottongrass, sedge, cloudberry, cranberry, as well as some semi-shrubs whose branches can give adventitious roots when the lower part begins to grow.hide in the moss. Such plants also include heather, rosemary, dwarf birch, etc. Cranberries spread over the surface of the moss in long lashes, sundew forms a rosette of leaves every year, lying on a sphagnum carpet. Some herbaceous plants of Russia are also found here: sphagnum bogs are inhabited by sundew, pemphigus, and sedge. In order not to be buried in sphagnum, they all tend to move their growing point higher and higher. Most plants are short and have small, evergreen leaves.
From the tree species in the swamp, you can most often see pine. Although it usually looks completely different than the one that grows on pine forest sands. The trunk of a tree growing in dry land is usually slender and thick. The swamp pine is undersized (no more than two meters high), clumsy. Its needles are short, and the cones are very small. In the cross section of a thin trunk, you can see a large number of annual rings.
Trees inhabiting pine-sphagnum swamps do not have adventitious roots. Therefore, they are gradually overgrown with peat. Caught at great depths, the roots can no longer supply enough moisture to the leaves, as a result of which the pine withers and dies.
Human use of swamps
The swamps are of great value as sources of peat deposits used as fuel, as well as a source of electricity for a number of power plants. In addition, peat is used in agriculture: it is used for fertilizers, bedding for livestock. ATindustry, it is used to make insulating boards, various chemicals (methyl alcohol, paraffin, creosote, etc.).
The raised sphagnum bogs are of great economic importance, which are the main places for the growth of berry shrubs: cranberries, cloudberries, blueberries.
The result of anthropogenic impact
Recently, the economic activity carried out by a person in swamps or adjacent territories causes a change in marsh vegetation. Such impacts include the drainage of marshes, fires, grazing, tree felling, and the laying of highways and oil pipelines. Wetlands close to industrial centers often suffer from atmospheric and soil pollution.
Clearing quarterly clearings is accompanied by felling of pine, which leads to the growth of swamp bushes, to which birch joins. Sphagnum is gradually being replaced by brier mosses.
Vegetation burns out as a result of fires, which often occur during dry periods. In these areas, the surface of the swamp is covered with a large amount of ash, which creates a supply of mineral nutrients. This leads to the fact that cottongrass, podbel, blueberries begin to grow abundantly at the site of the fires, wild rosemary and birch appear.
Drainage of swamps is carried out for the purpose of peat extraction, agricultural development, forestry, etc. At the same time, the level of soil-groundwater, oxidative processes and mineralization of organic substances develop. All this leads to a decrease in peat deposits, the growth of birch. Cranberries and cotton grass are gradually being replaced by cloudberries, and sphagnum mosses are being replaced by forest mosses.
Any human impact on the swamp leads to a change in the normal functioning of the entire landscape and, as a result, to a violation of the ecological balance in nature.
