Horus is primarily due to their latitudinal position. Moreover, it depends on the length mountain system, its height, barrier role, steepness and exposure of slopes, etc. The presence of altitudinal-zone differentiation of vegetation is the main regularity of the structure of mountain vegetation, which has no analogues on the plain. Separate altitudinal belts of mountains are often formed by communities belonging to the same typological category (type of vegetation, formation, etc.) as the vegetation of the plains, their typological difference is manifested at a rather low syntaxonomic level. These include tundra, taiga and widely deciduous forests, steppe, desert. However, there is also specific vegetation in the mountains, usually in the highlands, which has no analogue on the plains: nival, alpine, etc.
In the north of the European part of Russia, this is the East Scandinavian group (81) with mountain lichen tundra, birch open forests and mountain taiga forests (, Lovozero, etc.) and East European low mountains (82) nival-high arctic-arctotundra 2. In the south of Russia, this is the northern macroslope of the Caucasus with a well-pronounced alpine system of belts in its Caucasian version (84). The mid-mountain part of the Caucasus in the region of Novorossiysk - Gelendzhik is characterized by two belts - shilyak and broad-leaved forest (83).
The Urals is not only an important geographical boundary, dividing Europe and Asia, but also a phytogeographic one, connecting the Eastern European and Western Siberian regional complexes. The Urals, like all large mountain ranges, have a significant impact on the vegetation of the adjacent plains. As a result, a peculiar regional Ural complex stands out among the boreal vegetation, bearing the features of European and Siberian taiga forests. The Urals itself, with its huge meridional extent, is divided on the map into 7 latitudinal segments (85-91).
Mountain vegetation dominates in the east of Russia.
The Central Siberian system of low mountains and high plateaus forms, as it were, one continuous chain of vegetation types from mountain-tundra in Taimyr (Byrranga (92) to mountain-middle taiga on the Yenisei Ridge (95). The South Siberian mountain system includes the Sayan Mountains and Altai (96-98). Vegetation of the South Siberian mountains is extremely diverse - from mountain-tundra and alpine formations on the peaks to forest-steppe and steppe formations on the slopes of southern exposures. largest areas occupied by mountain taiga forests, among which cedar and fir-cedar forests predominate. Fir subnemoral, so-called black, forests occur sporadically. In the East Siberian and Chukchi mountain systems, from north to south, there is, as it were, an increase in the number altitudinal belts from mountain-tundra to mountain-northern taiga. It should be noted that in the south (East Siberian group) the role of Siberian dwarf pine becomes noticeable for the first time (102).
A belt of dwarf pine stands out especially in the mountains of the Okhotsk-Bering group (107-108).
The role of elfin continues to be significant in the mountains of the Baikal-Dzhugdzhur system, especially on the Dzhugdzhur and ridge itself. The southernmost in this group is the Borshchevochny Range, where the forest-steppe complex is well expressed, bringing it closer to the mountains.
Mountain vegetation Far East(116-121) and
The main pattern of differentiation of vegetation cover in the mountains, as well as soil cover, is altitudinal zonality, which geobotanists and botanical geographers call altitudinal zonality. Due to the imposition of the influence of exposure on it, a different substrate due to the often changing in space rocks, differences in the steepness of slopes, the distribution of moisture, etc. The vegetation cover, like the soil, is very complex and diverse. In the mountains, whatever the slope, the conditions for the existence of plants are different. The manifestation of the main climatic factors in the mountains is complicated by changes in the height of the terrain above sea level and the strong indentation of the relief. Associated with this is the belt character of the distribution of vegetation in the mountains, on the one hand, and the extreme heterogeneity of vegetation throughout each belt, on the other. Due to the dissection of the relief, the conditions for plowing the surface in the mountains are much worse than on the plains, and even where, according to the characteristics of the climate, agricultural crops could grow, the natural vegetation cover was by no means always reduced to arable land. forests as in temperate zone, and in the subtropics and tropics, they were destroyed mainly for the purpose of obtaining wood. Forest fires caused great damage to mountain forests. But in general, the vegetation in the mountains is much better preserved than on the cultivated plains. The degree of preservation, of course, is different, it is lower in densely populated areas, for example, in European countries. Noticeable, for example, is the best preservation of the pristine nature of the Pyrenees in comparison with other mountains of Europe. But ahead of them in this respect is the Caucasus, which can be attributed not to Europe, but to Western Asia. Indeed, in the Caucasus, natural vegetation, including forest vegetation, has largely been preserved. The trees in the mountain beech forests of the Caucasus are striking in their size, beech forests Giant spruces and firs grow. A strip of dark coniferous forests is clearly visible in the drawings of the mountains of the Western and Central Caucasus. At the upper border of the forest, the trees become oppressed, suffer not only from more low temperatures, but also from snow blockages and avalanches. The upper edge of the forest in the mountains of the Caucasus is usually made up of beech and birch crooked forests, sparse forests of alpine maple (Trautfetter's maple). In the Western Caucasus, at the upper border of the forest, thickets of Caucasian blueberries grow, the leaves of which, like those of the Pontic azalea that runs high into the mountains, acquire a blood-red hue in autumn. In the Carpathians, in their Ukrainian part and on foreign territory, at the upper edge of the forest, there is a strip of mountain (dwarf) pine. Separate spruce trees, sometimes cedar (cedar pine), penetrate into it, acquiring a flag-shaped crown from cold winds. In the Alps, the upper edge of the forest is formed by spruce, pine or European larch. On Mount Terminillo in the Apennines and in the Cantabrian mountains, in particular on their highest massif of Picos de Europa, beech rises to the upper edge of the forest. In the taiga mountains Eastern Siberia and the Far East, thickets of dwarf cedar have grown densely under the tops of the bald mountains.
Cedar-dwarf larch sparse forests are characteristic. In the mountains of Tuva, at the upper border of the forest, fir turns into elfin. The upper boundary of the forest is climatically determined mainly by the thermal factor, while the lower boundary is due to moisture. In the mountains of Europe and the Caucasus, the upper border of the forest is strongly influenced by anthropogenic factor, due to which, for example, in the Alps, Carpathians and the Caucasus, it is greatly reduced in comparison with the natural level. In the High Tatras, 70% of the length of the upper forest boundary is secondary. The activity of avalanches also plays an exceptionally large role. Avalanches also reduce the border of the forest, create combs in the upper belt of forest vegetation, often reaching the bottom of the valleys. With avalanches, as well as with accumulations of snow in hollows and with temperature inversions, the characteristic jaggedness of the upper forest boundary is associated both in the Caucasus and in the Alps. The upper edge of the forest is a fundamentally important boundary in the structure of altitudinal zonation. Separating wooded slopes from treeless highlands, it serves as a natural boundary of the first rank in the vertical (altitude) differentiation of vegetation cover. Mountain forests are of great importance in natural processes, life and preservation of landscapes. Everywhere their anti-erosion, soil-protective and water-protective role is great. The greater the intensity of potential soil erosion, the higher the value of the anti-erosion function of the forest. Forests serve as an important protection against mudflows, and they play the role mainly not of a direct mechanical protection, but of an obstacle to the rapid flow of water to the drainage channels from the watersheds. The trees of the upper forest belts serve as direct protection against the destructive action of avalanches, including the destruction of forests located below. According to observations in the regions of the Caucasus on avalanche slopes conifers at the upper edge of the forest, they are replaced by deciduous ones, and the strip of light forests and crooked forests expands significantly. Here there is a confrontation between the forest and snow masses. According to Czechoslovak researchers, in the Slovak sector of the Western Carpathians, all forests occupying a strip more than 200 m wide and located above 1200 m above sea level perform anti-avalanche functions. m. on slopes falling at an angle of 25 ° or more.
However, mountain air contains very little moisture. One of the characteristic features mountain nature- decrease with height of atmospheric pressure. For example, at an altitude of 5500 m Atmosphere pressure almost half that at sea level. In addition, with height, the partial (partial) pressure of oxygen in the air decreases, which at first makes it difficult, and in the end makes it impossible for the existence of living organisms. The vegetation of the mountains is very diverse and depends on climate zone. Their slopes can be covered with sprawling deciduous forests, majestic coniferous, bright, impenetrable tropical, but in any case, at an altitude of 1500–2000 m, their green rows gradually thin out, give way to shrubs, turning into dense grassy meadows called alpine. The higher, the fewer plants, only in some places, clinging to the clefts with roots, peep out shoots torn by the winds. From 3000–4500 m, the eternal kingdom of ice and snow begins - the snowy highlands.
In the mountains with the rise up from the foot to the peaks, climate change occurs. First of all, it changes temperature regime. The higher we climb the mountain slopes, the colder it gets. The tops of high mountains are covered with eternal snows. As you go up, the amount of precipitation also changes. Consequently, different altitude steps in the mountains have different climates. Therefore, the vegetation cover of the mountains forms a more or less distinct vertical, or altitudinal zonality(zonation).
The change of vertical belts of vegetation in the mountains during the ascent is somewhat reminiscent of the alternation of vegetation zones on the plain when moving from south to north. However, there is no complete correspondence between belts and zones, only some similarity is observed. For example, in the mountains of the Caucasus, as well as on the plains, coniferous forests follow broad-leaved forests. However, what follows is not the tundra, as on the plain, but subalpine and alpine meadows, which differ significantly from the tundra.
In different mountain systems, the number of vegetation belts varies greatly, due to a number of reasons. First of all, it depends on the height of the mountains: the higher the mountains, the more belts they have. The geographical position of the mountains is also important. The southern mountains, if they are high enough, have many belts. For example, in the mountains Central Asia the following belts can be observed: belt deserts, belt steppes, belt deciduous forests , belt coniferous forests, subalpine meadows, alpine meadows, eternal snow. AT northern mountains located in the taiga zone, there are few belts. The lowest one is the belt. coniferous forests- is replaced mountain tundra.
In the mountains located in the north, in a colder climate, the belt of coniferous forests falls relatively low, while in the southern mountains, on the contrary, it is located very high. Such differences are also observed in relation to the altitudinal position of other vegetation belts.
Within the same mountain system, the altitudinal position of the belts varies depending on the exposure of the slope. So, if any mountain range is directed from west to east, then the same belts of vegetation on the southern slope of the ridge will be located higher than on the northern one.
The flora of the mountains is usually characterized by high species richness. There are many endemic species that are not found on the plains. main reason The floristic richness of the mountains is an exceptional variety natural conditions.material from the site
The growth of endemic species in the mountains is primarily due to the fact that vegetable world highlands develop in isolation. There is no exchange of flora with surrounding areas. In the course of evolution, new species arise here that cannot spread to other territories. In addition, ancient species that have become extinct in other areas could be preserved in the mountains.
Belt subalpine meadows characterized by dense high herbage and rich species composition. grow here different kinds grasses and dicotyledonous plants: geraniums, gentians(rice. 196 ), ragworts, hogweeds, delphiniums, clover and many others.
On the alpine meadows plants are stunted, herbage is sparse. Some plants are pillow-shaped. For many species, the basal arrangement of leaves forming a basal rosette is characteristic. Flowers in plants of alpine meadows are larger than in the plains, and have a very bright color. Many plants in alpine meadows are highly resistant to freezing.
On this page, material on the topics:
A short message about subalpine and alpine grasslands
How does the vegetation change as you climb from the foot to the top of the mountain
Vertical belt change of vegetation in the mountains briefly
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The symbol of mountains is often called edelweiss, which can climb to a height of up to 5000 m. This amazing perennial grows in the highlands of Eurasia, except for the Caucasus. In alpine meadows, flowers that are more familiar to us grow - buttercups, gentians, crocuses. In the dry mountains of Central Asia, thorny, pillow-shaped plants, such as camel thorn, live. Below, in the same mountains, archa (mountain juniper) lives. Archa is the only tree in those places, and only the highlanders use it as firewood. In the alpine meadows, the African mountains of Kenya and Tanzania, there are giant ragworts and lobelia. Cushion-shaped and rosette plants also grow in the dry high-altitude valleys of the Andes at an altitude of about 4 km.
There are a lot of mosses and lichens that cover the soil, trunks, branches and even leaves of trees. A significant part of the terai and evergreen forests have been cleared for rice (in depressions) and tea bush (along the slopes). Above lies a belt of coniferous forests of silver fir (Abies webbiana), spruce (Picea smithiana, P. spinulosa), larch (Larix grif-flthii), tsuga (Tsuga brunoniana), junipers with lush shrub undergrowth. It is cold and snowy here in winter. Alpine meadows are located from 3700 to 4800 m. This is the kingdom of flowering (up to 380 species) primrose, gentian, fescue, etc. The highest limit of vegetation was noted when climbing Chomolungma at an altitude of 6218 m, where an arenaria (Arenaria musciformis) was found. At an altitude of 6000 m, edelweiss grows in some places, and at an altitude of 5500 m - fescue.
Vegetation layers
In the Himalayas, the tiered distribution of vegetation is clearly visible: terai (marshy jungle), evergreen tropical forests, deciduous, coniferous, mixed, alpine meadows are replaced from bottom to top.
On the northern, drier slopes, where the influence of the monsoon weakens, mountain steppes and semi-deserts dominate. At the foot of the mountains there are dry savannah and coniferous forests, and further on - somewhat denser deciduous forests. In the foothills of the western Himalayas, the dhak tree (Butea monospera) grows, which produces valuable resin and expensive wood. In the eastern part, up to a height of 1000 m, the slopes are covered with a damp and marshy jungle-type forest called "terai", which gives valuable wood sal tree (Shorea robusta). Above, the rainforest zone begins with bamboo, palm trees and tree ferns. From an altitude of 2000 m, deciduous forests with oaks, magnolias, chestnuts and maples predominate. Above 2600 m, coniferous trees are more common, including Himalayan pines and cedars.
From 3500 to 4000 m there is a layer of rhododendrons and dwarf shrubs, as well as alpine mosses. Above 5000 m - landscapes of the glyapial-nival belt. The boundary of eternal snows passes at an altitude of 4500 m (on the south side) and 6000 m (on the north side).
The vegetation of Russia is a significant part of the northern non-tropical vegetation of the world. Russia occupies most of northern Eurasia and therefore the regularities of the vegetation cover, manifested on its territory, are essential for understanding the botanical geography of the entire continent.
Among the most important botanical and geographical regularities of the macrostructure of the vegetation cover in Russia are the latitudinal, meridional and altitudinal differentiation of the vegetation cover.
Vegetation cover is characterized by systemic organization and multidimensionality. As divisions of the highest rank, the vegetation of the plains and the vegetation of the mountains stand out. This emphasizes the significant difference in the nature, composition and structure of the vegetation of the plains and mountains and their macro-ecological heterogeneity.
Regional differentiation of vegetation cover is expressed by regional complexes - sectors. The sectors are associated with such environmental parameters as moisture transfer features, the degree of oceanicity-continentality.
On the plains, subzonal categories of vegetation cover and / or their edaphic variants are distinguished. They are subordinated to regional complexes.
The vegetation of each mountain range is a typical altitudinal-belt series as a whole. The main feature of altitudinal belts is determined by the latitudinal position of the pedestal, height and meridional position.
vegetation of the plains
On the territory of Russia there are the East European and West Siberian plains, the vegetation of which demonstrates the classic change of zonal types. In the east, flat territories occupy small areas, yielding the main spaces to mountain ranges, and the clarity of the zonal division of vegetation is obscured. In the Pacific part of Russia, the influence of the ocean affects the patterns of zonal distribution of vegetation cover. The zoning structure is manifested in regional complexes. Each regional complex differs in the set of subzonal categories of vegetation. Vegetation categories of the same type in terms of latitudinal position in different sectors have different species composition.
Vegetation of the tundra type forms the cover of the Far North of the country, which stretches as a strip along the coast of the seas of the Arctic Ocean and is found on the islands. The main features of the tundra type of vegetation include the absence of a tree layer, the large role of low-growing small-tree plants (from shrubs and dwarfs to prostratic (creeping) shrubs and dwarf shrubs). Herbaceous perennials are widely distributed. The importance of mosses and lichens is great. The perforation of the vegetation cover is characteristic - the presence of spots of bare soil.
There are 5 regional complexes in the tundra. The westernmost, Atlantic, is represented only by the southern tundra with the participation Betula nana, Calluna vulgaris, Empetrum hermaphroditum, Carex bigelowii, in which boreal species, such as blueberries, are constantly found. The East European, West Siberian and Central Siberian sectors have the most complete zonal spectrum from high arctic to southern tundra. High arctic tundras are found only on some islands in the Arctic Ocean. A significant area of the islands is occupied by glaciers, and the vegetation cover is fragmentary. Herbaceous-lichen-moss spotted tundra dominate. Lichen-moss and moss-lichen communities (with an insignificant participation of flowering ones) are widespread, which are confined to strongly gravelly and stony soils. On the archipelago of Franz Josef Land and Novaya Zemlya (East European–West Siberian sector), tundra communities are found Deschampsia alpina, Cerastium arcticum, C. regelii ssp. caespitosum, which are not in the Central Siberian sector. Presence Ranunculus sabinii, Cerastium bialynickii, C.regelii s.str., Deschampsia brevifolia determine the specifics of the high arctic tundras of the Central Siberian sector. There are no high arctic tundras in the East Siberian and Chukchi regional complexes.
Arctic tundras are found in all but the Atlantic complexes. Shrubs begin to play an important role in them. For the East European - West Siberian sector, the background species is Salix nummularia, the role of Salix polaris, S. reptans, there are 2 types of vegetation Dryas - D. punctata and D. octopetala. In the East Siberian sector, the first place is taken by Cassiope tetragona, disappears D. octopetala. In Chukotka, Arctic tundra communities are characterized by Salix rotundifolia, S. phlebophylla, Dryas integrifolia, Carex lugens. Arctic tundra to the south are replaced by hypoarctic ones, which are represented by northern shrub-moss and southern shrub-moss-lichen subzonal categories. Their differences from sector to sector are also marked by geographically differentiating species (NN 4, 5, 8, 9, 11, 12, 14, 15) 1 .
Boreal (taiga) vegetation located in temperate latitudes south of the tundra. Taiga occupies a leading position in the north of Eurasia. It stretched from Scandinavia to Pacific Ocean. Most of taiga vegetation of Eurasia is concentrated on the territory of Russia. Taiga forests are also characteristic of many mountain systems, forming mountain-taiga belts in them.
The boreal vegetation of the plains includes 5 subzonal categories: from pre-tundra woodlands to subtaiga. It is characterized by the dominance of dark coniferous, light coniferous, small-leaved and mixed forests. Dominant types of coniferous forest species: Picea abies, P. obovata, Abies sibirica, Larix sibirica, L. gmelinii, L. cajanderi respectively replace each other from west to east, forming 7 regional complexes.
The shortest zonal spectrum in the Atlantic sector is represented by pre-tundra birch sparse forests (16). In combination with the southern shrub tundra, hilly and aapa swamps, they form the forest-tundra of the Kola Peninsula.
The Eastern European sector (East European Plain) has a complete zonal range from birch-spruce woodlands (17) to subtaiga (24, 25). Subzonal categories of vegetation are represented spruce forests(18, 20, 22, 24) and pine forests replacing them on soils of light mechanical composition (19, 21, 23, 25). In the subtaiga forests, the composition of the forest stand, in which spruce or pine dominate, or in the form of undergrowth, includes nemoral tree species: oak, linden, maple, hazel. This also includes coniferous broadleaf forests Kaliningrad region, in which there are Central European species - beech and hornbeam.
The forests of the Ural complex have features of the European and Siberian taiga. This regional complex is found on both sides of the Urals. A complete zonal series (26-32) is also expressed here, from spruce and larch-spruce woodlands to broad-leaved-fir-spruce subtaiga forests.
The Ob-Irtysh sector unites the forests of the largest taiga complex (33-42). The role of swamps in the structure of the vegetation cover of the West Siberian Plain is enormous. In terms of area, swamps here prevail over forests. The role of the vegetation of the vast Ob floodplain is great. (130).
In the north of the Ob-Irtysh, larch sparse forests predominate (33). large area occupy hilly swamps (124). To the south, light forests are replaced by northern taiga, where larch (36) and larch-pine (35) forests dominate. The watersheds are occupied by hilly and aapa bogs, huge upland bog systems with an abundance of lichens, and large lakes (126 b). Larch-spruce-cedar forests are also characteristic (34). In the middle taiga, spruce-cedar forests predominate, in places with fir, larch-pine forests are less common. In the middle taiga, the confinement of forests to river valleys is especially noticeable. There are many raised bogs on the watersheds.
In the southern taiga of Western Siberia, dark coniferous cedar-spruce-fir forests predominate. Pine forests dominate in the west. The presence of linden is typical in the southern taiga forests. On the watersheds, sphagnum raised bogs are common, forming systems that include aapa, including the famous Vasyugan bog.
The transition from the southern taiga to the subtaiga is gradual. Of the coniferous forests in the subtaiga, there are only pine forests on the sands (41). Birch and aspen forests predominate (42), they usually grow in small groves (choppings), alternating with damp meadows, swamps, and pine forests. Often birch groves are confined to depressions with pronounced solodization of soils.
The Central Siberian (43-47) and East Siberian (45-51) sectors have a shortened zonal section. AT Central Siberia there is no subtaiga; in Eastern Siberia, the latitudinal section ends with middle taiga forests. The boreal vegetation of these most continental sectors is formed by light coniferous, predominantly larch forests.
The boreal vegetation is enclosed by a peculiar Far Eastern complex. Features of its vegetation cover are associated with the originality of the floristic composition and complex physical and geographical conditions - the influence of the Pacific Ocean and monsoons in the southeast, the Sea of Okhotsk and the seas of the Arctic Ocean in the north, continentality air masses Siberia and Central Asia, relief complexity and geological structure. Northern taiga larch forests (52) occur in small areas along the coast of the Sea of Okhotsk; significant areas are occupied by middle taiga larch forests and sphagnum mari (53). Southern taiga forests are diverse: spruce-fir ( Рicea ajanensis, Abies nephrolepis), larch and pine-larch. In their forest stand are sporadically found Betula davurica, B. platyphylla; well developed undergrowth Rhododendron dauricum, Duschekia manshurica, Lespedeza bicolor, Corylus heterophylla. The subtaiga forests of the Far East are especially peculiar, represented by broad-leaved-pine and broad-leaved-larch forests with Mongolian oak and Manchurian birch (58.59), birch-pine (60) and spruce-fir-cedar forests with Pinus koraiensis, Picea ajanensis and Abies nephrolepis(57).
Nemoral vegetation It is represented by broad-leaved forests that grow in Russia only in the west (Eastern European regional complex) and in the east (Far Eastern complex). In the west of Europe, nemoral vegetation occupies almost its entire territory, and in East Asia descends much further south than in Europe, which is certainly due to the influence of the Pacific Ocean. In the continental regions of Siberia, broad-leaved forests are absent and are territorially replaced by steppes.
The broad-leaved forests of the Eastern European sector are represented by linden-oak with ash (61) and linden with oak (63). On light soils, they are replaced by pine-broad-leaved forests (62) and steppe pine forests with oak (64).
Strengthening of continental climate from west to east leads to a gradual reduction of European nemoral types of vegetation, of which only half reaches the western slopes of the Urals. The role of South Siberian light-loving and cold-resistant species becomes noticeable. An important frontier is the Volga, towards which many tree species, such as ash, shrubs and herbaceous species, gradually fall out from the west.
small groves oak forests are found quite far to the north in the subzone of the southern taiga (Leningrad, Novgorod, Pskov regions), and lime forests (probably derivatives that arose on the site of linden-spruce forests) are found even further north. In the south, broad-leaved forests along gullies and ravines, the so-called ravine forests, penetrate far into the steppe region.
In the Far East, broad-leaved forests are found in the south. In the southwestern part, they are represented by oak ( Quercus mongolica) and black-birch-oak. Some western oak forests have a cryophilized grass cover. In the eastern part, oak and mixed oak-broad-leaved forests are widespread with the participation of a mesophilic group of trees: Amur velvet, linden ( Tilia amurensis, T. mandshurica, T. taquetii) and creepers (65).
steppe vegetation Russia in the form of a strip extends from the western border of the country to the South Siberian mountains. To the east, steppes are found in isolated areas, mainly in intermountain basins. AT European Russia this strip is very wide and in the south reaches the Caucasus, and in Asian Russia - to the state border and continues in the countries of Central and Central Asia (Kazakhstan, Mongolia, China).
The steppe vegetation unites communities of xerophilic microthermal soddy herbaceous plants. The dominant biomorph in the steppes are turf grasses from the genera Stipa, Festuca, Agropyron, Koeleria, Poa, Cleistogenes, Helictotrichon etc. in different environmental conditions communities are formed from turf sedges, onions, herbs, semishrubs and shrubs. Steppe communities are polydominant, their distribution is associated with chernozems and chestnut soils.
In the steppe type of vegetation, 4 regional complexes are distinguished: East European, Trans-Volga, West Siberian and Transbaikal. The steppes of the Eastern European and Trans-Volga complexes are most fully represented and have a complete zonal spectrum; the West Siberian sector is represented only northern part zonal spectrum, and its southern part is in Kazakhstan. The Trans-Baikal complex unites disparate sections of steppes that occur in intermountain basins and are in florogenetic relationship with the Central Asian (Mongolian and Chinese) steppes.
There are 4 subzonal latitudinal categories of steppe vegetation: meadow, northern, middle and southern. The latitudinal differentiation of the steppes from north to south is associated with an increase in the degree of climate aridity, and its regional differentiation is associated with an increase in continentality.
Meadow steppes are the northernmost type of steppes. They are characterized by the predominance of forb-grass communities with a predominance of mesoxerophilic and xeromesophilic species, mainly loose shrub and rhizomatous grasses, rhizomatous sedges and forbs. Meadow steppes are common in the south of the nemoral region in the European part of Russia and the boreal region in Siberia. Together with forests (oak and oak-linden in the west and birch and aspen in Siberia), they form the forest-steppe subzone. Typologically, meadow steppes are considered within the steppe type of vegetation, but from a botanical and geographical point of view, they do not belong to the steppe zone, but are closely connected with forests and without anthropogenic intervention (haymaking, grazing), meadow steppes turn into forests.
Northern steppes begin zonal series steppe zone. They are characterized by the dominance of fescue-feather grass steppes, i.e. the dominance of turf grasses, with the participation of abundant xeromesophilic and mesoxerophilic forbs.
The middle steppes are also characterized by the predominance of fescue-feather grass steppes, but the forbs in them are much poorer and are represented by much more xerophilous species.
The southern steppes are distinguished by the participation of semishrubs as codominants in fescue-feather grass communities.
Throughout their range, steppe communities, especially within the same subzonal category, have big number general types. The identification of mapped steppe categories within regional complexes is therefore based on a small number of geographically differentiating species.
The Eastern European regional complex includes rich forb-grass meadow steppes with Bromopsis riparia, Carex humilis, Peucedanum macrophyllum; forbs - sod-cereal northern steppes with Stipa ucrainica; Stipa ucrainica; sagebrush-turfgrass southern steppes with Stipa lessingiana, Artemisia taurica, A. lercheana.
The Zavolzhsky regional complex combines rich forb-grass meadow steppes with Bromopsis riparia, Bromopsis inermis, Carex humilis, C. pediformis, Peucedanum alsaticum; forb-turf-grass northern steppes with Stipa zalesskii, S. korshinskyi; sod-cereal middle steppes with Stipa lessingiana; wormwood-bunchgrass southern steppes with Stipa sareptana, Artemisia lercheana.
The West Siberian sector, the western border of which runs along the Ishim River, includes only 2 northern latitudinal categories: rich forb-cereal meadow steppes with Bromopsis inermis, Stipa zalesskii, Carex pediformis, C. supina, Peucedanum morisonii and forb-turf-cereal northern steppes with Stipa capillata, S. zalesskii, Helictotrichon desertorum. The steppe soils of this sector are characterized by salinity.
The Transbaikalian regional complex is characterized by great originality species composition steppe communities, since it is florogenetically connected with the Central Asian steppes, and from the European-West Siberian, representing part of the Black Sea-Kazakhstan steppes, it is separated not only botanically and geographically, but also territorially by the South Siberian mountain ranges. It includes 3 latitudinal categories: rich forb-grass meadow steppes with Filifolium sibiricum, Peucedanum baicalense; forb-turf-cereal northern steppes with Stipa baicalensis, Leymus chinensis and turf-cereal middle steppes with Stipa krylovii.
Steppe communities and their fragments penetrate far to the north of Eastern Siberia, which is associated with a sharp continental climate, but above all with historical paleogeographic events that took place in this territory in the Pleistocene.
desert vegetation completes the zonal series of vegetation types of the plains. The desert type includes communities with dominance of xerophilic, hyperxerophilic micro- and mesothermic plants of various life forms, predominantly semi-shrubs, semi-shrubs and shrubs, semi-trees. In desert communities, ephemeroids and hemiephemeroids, perennial short-vegetative plants, are often abundant; annual herbaceous plants summer-autumn vegetation and ephemera - annual herbaceous plants of spring, autumn-spring or autumn-winter vegetation. In Russia, there is only a small section of a vast area of deserts. It is represented by the Caspian sector of temperate deserts, which belong to the northern latitudinal category: wormwood (79) and sandy wormwood (80) northern deserts. Their distribution is associated with brown soils. In the Caspian region, soils of light mechanical composition, sandy and sandy loam are widespread, therefore, along with wormwood, grass is often found here. Poa bulbosa.
Mountain vegetation
The altitudinal-zonal differentiation of the vegetation of the mountains is primarily due to their latitudinal position. In addition, it depends on the length of the mountain system, its height, barrier role, steepness and exposure of slopes, etc. The presence of altitudinal-zone differentiation of vegetation is the main regularity of the structure of mountain vegetation, which has no analogues on the plain. Separate altitudinal belts of mountains are often formed by communities belonging to the same typological category (type of vegetation, formation, etc.) as the vegetation of the plains, their typological difference is manifested at a rather low syntaxonomic level. These include tundra, taiga and broad-leaved forests, steppes, and deserts. However, there is also specific vegetation in the mountains, usually in the highlands, which has no analogue on the plains: nival, alpine, etc.
In the north of the European part of Russia, these are the East Scandinavian group (81) with mountain lichen tundra, open birch forests and mountain taiga forests (Khibiny, Lovozero, etc.) and East European low mountains (82) nival-high arctic-arctotundra 2 . In the south of Russia, this is the northern macroslope of the Caucasus with a well-pronounced alpine system of belts in its Caucasian version (84). The mid-mountain part of the Caucasus in the region of Novorossiysk - Gelendzhik is characterized by two belts - shilyak and broad-leaved forest (83).
The Urals is not only an important geographical boundary, dividing Europe and Asia, but also a phytogeographic one, connecting the Eastern European and Western Siberian regional complexes. The Urals, like all large mountain ranges, have a significant impact on the vegetation of the adjacent plains. As a result, a peculiar regional Ural complex stands out among the boreal vegetation, bearing the features of European and Siberian taiga forests. The Urals itself, with its huge meridional extent, is divided on the map into 7 latitudinal segments (85-91).
Mountain vegetation dominates in the east of Russia.
The Central Siberian system of low mountains and high plateaus forms, as it were, one continuous chain of vegetation types from the mountain-tundra in Taimyr (Byrranga (92) to the mountain-middle taiga on the Yenisei Ridge (95). The South Siberian mountain system includes the Sayans, Kuznetsk Alatau and Altai (96-98) The vegetation of the South Siberian mountains is extremely diverse - from mountain-tundra and alpine formations on the peaks to forest-steppe and steppe formations on the slopes of southern exposures.But the largest areas are occupied by mountain-taiga forests, among which cedar and fir-cedar forests predominate.Sporadically there are subnemoral fir, so-called black, forests. In the East Siberian and Chukchi mountain systems, from north to south, there is, as it were, an increase in the number of altitudinal belts from mountain-tundra to mountain-northern taiga.It should be noted that in the south of the Verkhoyansk Range (East Siberian group), the role of Siberian dwarf pine becomes noticeable for the first time (102).
A belt of dwarf pine stands out especially in the mountains of the Okhotsk-Bering group (107-108).
The role of elfin still remains significant in the mountains of the Baikal-Dzhugdzhur system, especially on the Dzhugdzhur ridge itself and the Stanovoy Upland. The southernmost in this group is the Borshchevochny Range, where the forest-steppe complex is well expressed, bringing it closer to the mountains of Mongolia.
The vegetation of the mountains of the Far East (116-121) and Kamchatka is strongly influenced by the Pacific Ocean. Common to all is the structure of the upper altitudinal belts of vegetation: mountain-tundra, subalpine with thickets of elfin cedar, in places alder and the participation of stone birch. Taiga and broad-leaved belts are specific.
Vegetation of swamps and floodplains
The vegetation of swamps plays a huge role in the structure of the tundra and taiga, often determining this structure, for example, in Western Siberia, in the northeast of European Russia, in Eastern Fennoscandia. Bogs are specific ecosystems, the vegetation of which is controlled primarily by the amount and trophicity of water and is characterized by poor floristic composition, heterogeneity and complexity of composition. Polygonal swamps are confined to the north of the tundra region, and hilly swamps are located to the south. The distribution of ridge-hollow grass-phagnum-hypnum bogs (aapa) is associated with the south of the tundra region and the taiga. In the taiga region, sphagnum bogs reach their optimum development. It should be noted the asymmetry in the distribution of swamp vegetation on the East European and West Siberian plains. So the northern border of the vegetation of hilly bogs in Europe almost coincides with the northern border of the northern taiga, and in Western Siberia they are still widespread in the northern taiga, that is, the boundaries of raised bogs in Siberia are shifted to the south. Polygonal swamps are widespread in the north of the Asian part of Russia. In the Eastern European (Malozemelskaya) tundra western border their distribution is the river Neruta.
The significance of the vegetation of river floodplains is also great and varied. Many large rivers are major botanical and geographical boundaries, for example, the Volga, Don, Onega, Yenisei, river floodplains are a kind of corridors connecting vegetation of different latitudinal categories. The floodplains are characterized by natural heterogeneity and dynamism of the vegetation cover, due to the erosive-accumulative activity of rivers. hallmark vegetation floodplain tundra region is the lack of forests. The boreal floodplains are characterized by the development of high levels dark coniferous forests, and in the floodplains of subtaiga, broad-leaved and steppe regions– development of broad-leaved (in the European part of Russia) and other hardwood, in places pine forests. In the floodplains of the southern part of the steppe and desert regions, forests grow only in the riverine part. In the estuarine parts southern rivers meadows and reed beds develop, and northern rivers- meadows, swamps, grass marches.
It is necessary to preserve and restore the unique diversity of the country's vegetation cover - the source of life on Earth.
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