Botany - B.Ye. Yakubenko 2017

Part Three. The Plant Kingdom (Plantae)
Chapter XII. Fundamentals of Phytocenology. The Concept of Vegetation
12.4. Systematics of Phytocenoses

Natural vegetation is formed by numerous phytocoenoses. In geobotany, the following systematic categories are distinguished and used: association, association group, formation, formation group, formation Class, and vegetation type.

The basic systematic unit of vegetation is the association, which is characterized by a specific floristic composition, Structure, and phytocoenotic relationships driven by the interaction of plants with their living conditions, as well as distinct economic properties. Examples of an association include Scots pine—bilberry—Schreber's moss, and meadow fescue—red clover—field stitchwort.

A higher-ranking taxonomic unit is the association group. It unites genetically related associations. For instance, the Scots pine—Schreber's moss and Scots pine—wavy Hair-moss associations are grouped into the green moss pine forest association group based on the character of their moss cover.

A formation is a higher taxonomic unit of vegetation that unites closely related association groups based on a shared dominant species. For example, green moss, lichen, and forb pine forests are united by the dominance of the tree canopy (Scots pine) into the Scots pine forest formation.

Formations, in turn, are united into formation groups. For example, the Scots pine, Crimean pine, and mountain pine formations are united into the pine forests formation group.

Formation groups are united into formation classes According to the life-form type of the main edificators. For example, pine, spruce, and fir forests are united into the coniferous forests formation class.

The highest systematic unit of vegetation is the vegetation type, which consists of formation classes. For example, the forest vegetation type unites coniferous and deciduous forests. The main vegetation types include: woody, herbaceous, desert, and wandering (aquatic plants or hydrophytes not attached to a substrate).

Latitudinal Zonation and Vertical Altitudinal Zonation of Ukraine's Vegetation

The territory of Ukraine clearly exhibits latitudinal zonation and vertical altitudinal zonation in the distribution of its plant cover. Latitudinal zonation is driven by Ukraine's vast territory (it stretches from west to east for up to 1200 км, and from north to south for up to 900 км) as well as the climatic heterogeneity of its regions. Latitudinal zonation is clearly manifested from north to south and is represented by the following zones: Polissia, Forest-Steppe, and Steppe. Vertical zonation is associated with the mountain systems of the Carpathians and Crimea, where mountain and foothill districts are distinguished. Latitudinal zonation is limited by climatic conditions, whereas vertical zonation is determined by орографічними [orographic] conditions, primarily elevation above sea level—with every 100 м ascent into the mountains, the mean annual Temperature drops by 0.55°C, and the vegetation changes accordingly from bottom to top, just as it does from south to north in the plains.

The Polissia Zone

Polissia represents only a minor southern portion of the vast Polissia Lowland, the greater part of which lies within Belarus and neighboring countries. Ukrainian Polissia slopes toward the Pripyat Lowland, and is bordered on the south by uplands with elevations up to 300 м. Numerous tributaries of the Pripyat, Dnieper, and Desna rivers originate here. Their basins significantly influence the character of the plant cover and its articulation. The soils are sod-podzolic, developing on fluvioglacial sands. Boggy and waterlogged lands are less widespread. The climate is temperate. The mean annual precipitation is 550—650 мм, and the mean annual temperature is 5.5 °C.

Under these conditions, the plant cover develops quite well. The flora of Polissia numbers from 1,550 (Barbarych, 1955) to 1,860 species (Andriienko, Shelyag-Sosonko, 1983). The systematic STRUCTURE OF THE flora is dominated by species from ten leading families, among which grasses, asters, sedges, legumes, pinks, willows, roses, figworts, deadnettles, and buckwheats hold a special place, accounting for up to 60–70% of all plant species in this zone. A distinct feature of the biomorphological structure of the flora is the relatively small proportion of woody forms, with a dominance of herbaceous and moss plant species. Among the mosses, one can find almost all sphagnum species growing in Ukraine, as well as numerous species of hydrophilic green mosses.

Forest Vegetation. Forest vegetation predominates in The structure of Polissia's natural vegetation, with pine forests accounting for over 50% of it. They are formed by Scots pine, which under optimal conditions reaches a height of 25—30 м, and under unfavorable conditions—4—6 м. Pine forms pure or mixed pine forests. On sandy hills with deep groundwater tables and poor sod-podzolic soils, it forms pine-lichen communities with a sparse plant cover beneath the tree canopy. These conditions correspond to a specific flora of medicinal plants. Along the slopes of dune hills, leveled areas, and under better soil conditions with a higher groundwater table, pine-green moss communities develop, featuring a more diverse herb-shrub layer and a continuous or substantial cover of green mosses. Medicinal plants grow here as well.

Depressed areas with sod-podzolic gley soils and groundwater tables up to 1.0 м deep are covered by long-moss pine forests. Unfavorable soil and climatic conditions impair The Development of trees and their associated species. Consequently, There is a small number of herb and dwarf-shrub species alongside an almost continuous cover of common haircap moss combined with sphagnums and other hygrophilous green mosses.

Pine-sphagnum communities with a continuous cover of sphagnum mosses and a low-productivity tree stand develop around bogs and in depressions with permanent surface waterlogging.

Oak forests occupy a significant place in the forest vegetation structure. They are formed by English oak, which under optimal conditions reaches 20—30 м in height and forms high-bonitet communities. Oak forests can be pure, monodominant (formed solely by the main edificator), or mixed (with the participation of other deciduous species, more frequently birch, hornbeam, and less commonly alder and aspen, etc.). These are broadleaf forests that, in turn, can form simple tree stands (consisting only of forest-forming species) or complex ones, where, alongside tree species, shrub, half-shrub, and herbaceous plant species are present. Unlike pine forests, oak forests possess a richer and more diverse floristic composition featuring a variety of medicinal plants (in pine forests—speedwell, bearberry, yellow azalea, common heather, bilberry, lingonberry, bog bilberry, staghorn clubmoss; in bogs—marsh cinquefoil, cranberry, marsh Labrador tea; in alder swamps—frangula, stinging nettle, raspberry, black currant, common hop, etc.).

Birch forests formed by silver birch (Betula pendula Roth.) and downy birch (B. pubescens Ehrh.) account for up to 10% of the forest vegetation area in Polissia. They frequently arise in place of pine or oak forests, meaning that most of them are secondary in origin. Smaller areas are occupied by climax birch forests, mainly in boggy and waterlogged habitats.

Under optimal habitat conditions, birch forests form tree stands up to 20—30 м tall with trunk diameters of 14—40 см. The trees have well-cleared trunks with a fairly high-set crown, and a canopy closure of 0.4—0.8. Over time, the stand thins out, and by the age of 80, up to 350 trees remain per 1 га. Such sparseness of the canopy promotes the growth of numerous dwarf-shrub and herbaceous species, among which are quite a few medicinal plants. They grow abundantly in birch-smallreed and birch-grass-forb types on dry sod-podzolic soils. They are less abundant in birch-bilberry, birch-fern, and birch-sphagnum communities, where marsh cinquefoil can be harvested en masse.

Alder forests occupy fourth place in Polissia, accounting for over 6% of the forested area. These are forests growing on mineral soils with a high groundwater table and sod-gley soils, as well as communities confined to bog soils whose surface is heavily moistened or flooded and differentiated into hummocks around tree trunks and hollows between them. Black alder settles on elevations, reaching 26—28 м in height under conditions of flowing Water at 50—60 years of age, and 14—18 м when water is stagnant. The tree trunks are columnar, well-cleared, with a high-set, dense crown. Trunk diameters range from 14—48 см, and canopy closure from 0.5—1.0. The most typical communities of alder forests include alder-raspberry, alder-nettle, alder-fern, alder-meadowsweet, alder-sedge, alder-reed, alder-forb, and others. Quite a few species with medicinal properties grow in alder forests. Furthermore, some of them (raspberry, stinging nettle, glossy buckthorn, naked meadowsweet, common hop, marsh cinquefoil, etc.) grow in great quantities and can serve as objects for the industrial harvesting of medicinal raw Materials.

Aspen, hornbeam, poplar, and other forests hold a smaller specific weight in the composition of forest vegetation, yet a considerable number of medicinal plant species also grow beneath their canopy.

Meadow Vegetation. Meadow vegetation in Polissia ranks second after forest vegetation, with which it is genetically linked, as many meadows have appeared in place of cleared valuable forests. In the region, areas occupied by meadow vegetation are used as hayfields or pastures, and meadows are of vital importance for the local economy and farming.

According to their geomorphological confinement, meadow vegetation includes plain and mountain meadows and pastures. Plain conditions, in turn, distinguish continental and floodplain meadows, while continental ones are divided into upland and lowland. Based on phytocoenotic properties and habitat conditions, the following meadow classes are distinguished—true, steppe-like, boggy, wasteland, and peat meadows—which unite specific formations.

Floodplain meadows are very widespread in the current plant cover. They occupy river floodplains and are annually inundated during spring floods by overflow waters that deposit fine-earth particles enriched with ash elements onto the floodplain. Consequently, river floodplains feature the richest and most species-diverse natural lands. They are dominated by true meadows and their numerous meadow communities. These are mostly meadow-bluegrass, meadow-fescue, meadow-foxtail, and genetically related communities. Numerous medicinal plants grow among the forbs of floodplain meadows, notably marsh cinquefoil (boggy meadows), tormentil, valerian, meadowsweet, and centaury species, among others. A significant number of meadow medicinal plants also possess fodder value, containing Vitamins, protein, fiber, and other beneficial properties. These meadows are not only the most productive but also the most valuable in terms of fodder.

Bog Vegetation. Ukraine has over 2 million га of undrained peat bogs with a peat depth of at least 0.5 м. Substantial areas are occupied by waterlogged lands with a peat layer thickness of less than 0.5 м. Together, they constitute a significant reclamation fund of the Polissia zone. Many of them are currently drained and have undergone considerable changes in both peatland structure and plant cover. This is clearly noticeable in the shift of the plant cover, whose floristic composition is undergoing a process of mesophytization. Thus, waterlogged sedge and sedge-hypnum phytocoenoses have been replaced by grass-sedge and grass-forb or grassy communities that are close in nature to meadows. Therefore, as in meadow phytocoenoses, the presence of medicinal plants increases in their composition, particularly marsh cinquefoil, cranberry, marsh Labrador tea, bur-marigold, and water pepper.

Three types of bogs are widespread in Polissia: lowland, transitional, and raised.

Fen mires are the richest and most diverse. The most common are open, treeless mires. Many of them are located in river valleys and are therefore called valley mires. There are oxbow mires that formed in the beds of former rivers after the retreat of the glacier. A considerable number of valley mires originated in the beds of open and closed depressions. Many mires are of lacustrine origin, with the lower layers of their peat deposits represented by sapropel rich in phosphorus, making them valuable for use as field fertilizers. All these mires and their peats contain relatively high amounts of nitrogen and ash elements, which is why an abundant cover with high floristic richness develops on them, including medicinal plants.

Transitional mires, in which peat contains less nitrogen and fewer ash elements, are habitats for plant communities with a poorer floristic composition. They are represented almost exclusively by wood-bog communities, and to a lesser extent by shrub-Sphagnum ones.

Raised bogs are the least common in Polissia; their characteristic feature is a tree layer, a shrub layer belonging to the Ericaceae family, and a continuous moss cover. The floristic composition of raised bogs is poor and includes a small number of medicinal plants.

Aquatic and semi-aquatic vegetation. Polissia has A large number of lakes and rivers, in the coastal zones and water surfaces of which specific aquatic and wetland communities develop. Some of these include Medicinal Plants and may be of interest for the harvesting of medicinal raw materials.

Psammophytic vegetation. Polissia features numerous open and loosely fixed sandy soils that support specific psammophytic vegetation. These are predominantly Corynephorus communities, as well as grass-forb and forb communities, which also harbor medicinal plants.

Forest-Steppe Zone

The Forest-Steppe occupies an intermediate position between the Polissia and Steppe zones, combining features of both forest and steppe, as well as steppe and forest vegetation. This is facilitated by the zone's physiographic, soil, and climatic conditions. In the Forest-Steppe, the continental climate proved optimal for the northward penetration of southern steppe plant communities, as well as for forest-forming species and their associated suites of plants with xeromorphic impregnation traits into steppe communities. In the southward direction, the deep chernozem and leached chernozem soils of the zone's dissected relief were favorable for their spread. With an average annual temperature of 6–7 °C, a sufficient amount of moisture (annual precipitation up to 450–550 мм), and a fairly extensive hydrographic network of rivers and lakes rich in soil varieties, optimal conditions have formed here for the abundant development of medicinal plants distinguished by high medicinal qualities (Carex parvula, Agrimonia eupatoria, Origanum vulgare, etc.). Consequently, the Forest-Steppe is a bountiful region for harvesting medicinal raw materials.

The vegetation cover of the Forest-Steppe is highly diverse, represented by forest, meadow, mire, halophytic, psammophytic, aquatic-coastal, and other communities.

Forest vegetation of the Forest-Steppe is represented by broad-leaved, mixed, and coniferous forests, which include a considerable number of arboreal species. Oak forests occupy a leading position in the structure of the Forest-Steppe's forest vegetation, accounting for up to 25% of the forested area. This is where up to 70% of Ukraine's oak forests are concentrated, serving as the main supply base for oak timber, which is of paramount importance to the country's economy. Oak forests are formed by Quercus robur and Q. petraea, while in the Crimean Forest-Steppe they are formed by Quercus pubescens and Quercus petraea.

Oak forests can be simple monodominant, formed by a single species of forest-forming tree (e.g., Quercus robur), or complex, where the stand is formed by two, three, or more forest-forming species, with tiering of the tree canopy, shrub, and dwarf-shrub-herbaceous cover into distinct tiers and sub-tiers.

Oak woodlands are the richest forests in terms of forest-forming species and shrub layer composition, which is explained not only by the combination of forest and steppe plant species, but also by favorable soil-climatic ecological factors and coenotic conditions. Many tree and shrub species grow in oak forests. The main edificators of oak forests are: Quercus robur, Quercus petraea, and Quercus pubescens, which form respective forest communities typical of certain Regions of the country; Scots pine, European hornbeam, Oriental hornbeam, ash, small-leaved linden, Norway spruce, black alder, European beech, and other forest species are most frequently added to the edificators as co-edificators. Their combination creates dense tree stands with high shading, providing favorable conditions for the growth of numerous species in the shrub and herbaceous layers.

A distinctive feature of the herbaceous cover is the abundant development of nemoral species—that is, broad-leaved species that develop in early spring before the leaves of the tree canopy unfold. During this time, they manage to fully complete their development cycle and produce seeds. Such perennial plants belong to the category of ephemeroids. They frequently include geophytes, plants that possess underground Organs in the form of rhizomes or bulbs. The most typical among them are Corydalis cava, Corydalis marschalliana, Corydalis solida, Anemone nemorosa, Anemone sylvestris, Anemone ranunculoides, Lathyrus vernus, Pulmonaria obscura, Viola mirabilis, Viola odorata, Primula elatior, Asarum europaeum, Lamium galeobdolon, Sanicula europaea, Mercurialis perennis, Dentaria bulbifera, and many others. Many of them (Pulmonaria obscura, Lamium galeobdolon, Sanicula europaea, Asarum europaeum, Origanum vulgare, etc.), as well as shrubs (hawthorn species and Rhamnus cathartica), are valuable medicinal plants widely used in medical and veterinary practice as therapeutic or prophylactic agents.

Meadow vegetation is quite widespread in the Forest-Steppe. It occupies large areas along river valleys and around lakes and ponds, and is frequently found along gullies, steep slopes, and watersheds. While mesophytic and hygro-mesophytic meadow communities are widespread in Polissia, xero-mesophytic and xerophytic communities are more common in the Forest-Steppe.

According to geomorphological affinity, meadow vegetation is represented by upland and floodplain meadows; upland meadows, in turn, are subdivided into dry-ground and lowland meadows. However, a Classification dividing meadow vegetation into classes—true meadows, steppe meadows, wasteland meadows, boggy meadows, and peaty meadows—is currently more widespread. True meadows are highly characteristic of the Forest-Steppe, among which bluegrass, meadow fescue, red fescue, meadow foxtail, timothy, tufted hairgrass, and other communities are prominent. They frequently combine with legumes to form grass-legume communities, and with forbs to form grass-forb and grass-legume-forb communities. Their composition includes many valuable forage and medicinal grasses.

In lowland meadows with sod-gley soils or a shallow surface layer of peat, boggy meadows develop, dominated by hygrophytic plant species, particularly grasses (creeping bentgrass, common bluegrass, marsh bluegrass, floating mannagrass) and sedges (carex nigra, carex vesicaria). Meadow-bog forbs are also quite abundant here.

Steppe meadows characterized by the dominance of sheep fescue, wood small-reed, couch grass, smooth brome in the grassy stand, and early sedge, Colchis sedge, etc., among sedges, are very typical for plakor plateaus, slopes, and elevations.

A feature of the meadow vegetation is the increasing participation of species with xeromorphic structure, members of the steppe forb group, and the appearance of feather grass species (Stipa tirsa, Stipa johnstonii) and densely tufted species.

The meadows of the Forest-Steppe harbor many high-quality medicinal plants. These include sage (Salvia pratensis), chicory, tansy, agrimony, oregano, immortelle (Helichrysum arenarium), wormwood (Artemisia absinthium, Artemisia vulgaris), milkvetch, pheasant's eye (Adonis vernalis), wood avens, birthwort (Aristolochia clematitis), thyme species, and others.

Mire vegetation in the Forest-Steppe zone covers over 220 thousand ha. It is represented predominantly by forest, shrub, and herbaceous, and to a lesser extent by herb-moss communities. Among them, the largest areas are occupied by sedge, sedge-hypnum, and tall-grass reed and cattail communities.

The mire flora includes numerous medicinal plants suitable for industrial harvesting of medicinal raw materials, in particular, beggar-ticks (Bidens tripartita), bog bean (Menyanthes trifoliata), water-pepper, calamus, wormwood, dock (Rumex hydrolapathum), stinging nettle, dandelion, and others.

Halophytic, psammophytic, petrophytic, and other Types of Vegetation are less represented in the Forest-Steppe.

Steppe Zone

The Steppe zone occupies a more southern position than the Forest-Steppe, which affects its physiographic conditions and the character of its vegetation cover. In this zone, the continentality of the climate increases—the average annual temperature rises to 7–8 °C, precipitation decreases to 250 мм per year, and sometimes even lower. Soils in the northern part are represented by deep chernozems, and in the southern part by chestnut soils with a high nitrogen content, ensuring high Abundance of vegetation development despite significant air and soil dryness.

Features of the steppe zone include: a low degree of afforestation, dominance of herbaceous communities in the vegetation structure, high xeromorphy of plant structures, saturation of the vegetation cover with perennials belonging to densely tufted grasses, and a high concentration of ephemerals and ephemeroids in the steppes.

Forest vegetation. Within the forest vegetation of the Steppe, various categories of oak forests—pine, willow, alder—and Other types of forest vegetation stand out for their volume and distribution.

Oak groves in the northern part of the zone form gallery forests (baryal forests), which are primarily distributed along ravine slopes, gully depressions, and eroded steep slopes. They do not cover large areas and serve a soil-protective rather than commercial role in the region. These are low-productivity stands with a fairly dense growth of thorny shrub species along their margins. In the steppe zone, the steppe cherry is frequently found in such thickets.

In the Southern Steppe, forest vegetation is predominantly represented by artificial protective forests. These include shelterbelts and small woodland patches (kolky) that develop along gullies and their thalwegs. By nature, these are willow, aspen, or other plant communities inhabiting gully bottoms that experience at least periodic waterlogging (in spring or autumn).

Pine forests in the Steppe are less common and are confined to light sandy soils. The Russian geobotanist G. I. Tanfilyev noted that if sandy soils stretched all the way from Polissia to the Black Sea, they would be inhabited by coniferous forests everywhere. These are mainly artificial pine plantations, which are particularly abundant in the Oleshky Sands (Oleshky Arena) in the lower Dnieper region.

Along rivers and in their deltas, around lakes and ponds, alder, willow, or poplar forests and groves frequently grow. Here, they play an important water-regulating and soil-protective role.

Steppe vegetation. This vegetation type is the most essential for this zone. Steppe vegetation differs from other types in that it is formed almost exclusively by perennial xerophytic grasses. Tightly tufted grasses account for 60–70% (locally up to 90%) of the grass stand. A characteristic feature of the steppes is the dominance of phytocenoses featuring Lessing's feather grass, Ukrainian feather grass, beautiful feather grass, hair-like feather grass, narrow-leaved feather grass, and feathery feather grass, among others. The Northern Steppe is characterized by vibrant forbs, whereas the Southern Steppe is distinguished by a muted appearance and the dominance of wheatgrass and wormwood species in the grass stand.

Consequently, the Steppe features sod-grass and rich-forb steppes, which are typical of the Northern Steppe on plateaus (plakorts) with chernozem soils and abundant mesophytic forbs, whereas the Southern Steppe is characterized by sod-grass, sparse-forb steppes on chestnut soils with sparse, less diverse forbs dominated by true xerophytes, along with an increased presence of ephemerals and ephemeroids. Their composition includes numerous southern steppe species, such as Sarepta sea-lavender, eastern ferula, field eryngo, woolly-flower milk-vetch, maiden pink, slender-leaved yarrow, Schrenk's tulip, slender cudweed, bulbous star-of-BETHLEHEM, and Ukrainian chickweed.

In the Northern Steppe, meadow steppes are widespread along gullies, depressions, and north-facing slopes; they differ from typical meadows by an increased proportion of xerophilous species and the dominance of sheep's fescue and feather grasses.

Medicinal plants of the Steppe include spiny Jerusalem sage, common oregano, woolly-flower milk-vetch, meadow sage, absinthe wormwood, spring pheasant's-eye, elecampane, Gmelin's sea-lavender, licorice, grey wallflower, German chamomile, common tansy, various thyme species, common agrimony, wood avens, and other species.

Bog vegetation. In the Steppe, bog vegetation is not widespread due to high insolation and insufficient moisture. Consequently, peat bogs do not form under these conditions; however, in the deltas of the Danube, Dniester, Dnieper, and certain other rivers, significant areas are occupied by bogs with mineral soils—that is, bogs lacking a thick layer of peat. These are lowland bogs. The largest of these is the Kardashenko Bog, which covers an area of over 5,000 га, while the rest are smaller in size.

The plant cover is characterized by tall-growing plant communities. Reed bogs are highly typical of this zone, forming dense thickets up to 2–3 м in height. Cattail, bulrush (Schoenoplectus), and water- and bog-sedge communities grow in water-submerged areas. Their distinctive features include a dense grass stand, high projective cover, and a poor, monotonous species composition. Consequently, only a small number of medicinal plants are found here.

Halophytic vegetation. This vegetation is typical of the Steppe and is confined to saline habitats. Based on The Nature of soil salinity, a distinction is made between solonchaks, solonetz soils, solonchakous solonetz soils, wet solonchaks, and other variants, while based on soil solution reaction and the content and diversity of salts, distinctions are made regarding chloride, sulfate, carbonate, and other types of salinity. Therefore, the plant cover of depressions, leveled areas, temporary steppe depressions (pods), saucer-shaped depressions, and other habitats is represented by diverse plant communities.

In the depressions of large river terraces and interfluves, solonetz and solonchak meadows are quite widespread. Solonetz meadows frequently form pure stands of giant puccinellia or stands of giant puccinellia combined with annual camphorwort and Bessarabian dandelion; on drier soils, they form stands of sheep's fescue, and on wetter or fresh soils, giant puccinellia.

Under carbonate salinity, elevated and less moistened areas are covered by communities of loose-flowered sedge, while more moistened areas feature creeping bentgrass, often accompanied by creeping couch grass, eastern fescue, white clover, sea arrowgrass, and Gerard's rush, among others.

Steppe patches covered with solonchaks and solonchakous soils, are overgrown with communities of prostrate glasswort, fleshy seablite, stalked halimione, scrubby seablite, sea aster, suede-like sea-lavender, couch grass, coastal-purslane, and elongated wheatgrass, which form pure stands or, more frequently, grow in combination with one another.

A characteristic feature of these plants is their ability to excrete salt, thereby neutralizing its negative impact on their physiological activity, as well as their capacity for salt accumulation. Growing under varying conditions of salt saturation, these plants accumulate salts that are of significant importance when evaluating them as medicinal raw materials.

Foothill and Mountain Regions of the Carpathians

The Carpathian region occupies the southwestern part of Ukraine and reaches its highest elevation within the Chornohora mountain range: Hoverla (2061 м), Petros (2028 м), and Pip Ivan (2010 м). The relief is mountainous, river valleys are deep, and slopes are steep with precipices and rock outcrops. Flysch rocks dominate the geological structure, with crystal schists, marbles, gneisses, and andesites capped by sedimentary rocks occurring less frequently. Sod-podzolic, brown-earth podzolic, and sod-brown-earth soils have formed on them.

The orographic factor plays a crucial role in climate formation. In the mountains at an elevation of 652 м (Yasinia), the average annual temperature is 6 °C, whereas at an elevation of 1266 м (Turbat) it is 3.2 °C; precipitation totals are 1100 and 1300 мм, respectively. Winters are long and snowy.

All of these physiographic conditions have left their mark on the development of natural vegetation. The primary limiting factor for vegetation distribution is altitude above sea level, as climate, soil cover, flora, and fauna change with elevation. The following vertical vegetation belts (zones) are clearly distinguished in the Carpathians: foothill, lower mountain forest, upper mountain forest, subalpine, and alpine (Fig. 116).

The foothill belt, reaching an altitude of 350–400 м, is characterized by a high degree of land cultivation. Vast areas of grain, industrial, and fodder crops, as well as orchards and vineyards, alternate with natural vegetation. Oak groves of English oak hold a high specific weight here, with canopy heights reaching 26–30 м, mixed with hornbeam and ash. Hazel, Tatar maple, one-seeded hawthorn, and European spindle grow in the understory, while the grass stand features quaking sedge, sweet woodruff, many-flowered Solomon's-seal, naked meadowsweet, and Balkan hemlock-parsley. Mixed oak woods dominated by sessile oak with the participation of European beech and hornbeam are less widespread.

Upland meadows, which emerged on the sites of felled forests, are represented by white bentgrass communities that locally form pure stands. In river floodplains on elevated sites, xerophilous meadows of sheep's fescue are widespread, while on leveled areas, common bentgrass communities occur with the participation of red fescue, creeping couch grass, white clover, and alsike clover.

The lower mountain forest belt lies above the foothills and reaches an altitude of 800–900 м. The vegetation structure is dominated by beech forests formed by European beech. These forests occupy about 30%, and in Transcarpathia up to 60%, of the forested area. Optimal conditions for their development occur at elevations of 600–800 м, where nearly pure or mixed single-tiered forest stands up to 40–45 м in height have developed. These are the most productive stands, yielding up to 600–800 m³/ha of high-quality timber. Due to heavy shading, understory-free beech forests or those with a sparse grass stand frequently occur.

The upper mountain forest belt covers the territory at elevations of 900–1450 м, which is covered by spruce forests. Mixed beech-fir tree stands up to 45 m high occur at the junction of the two belts. Above this narrow strip lie spruce forests formed by Norway spruce and mountain spruce. These single-tiered stands, reaching 50 м and more in height, are the most productive in Ukraine. They yield up to 1000–1200 m3/ha of high-quality timber. Fresh and moist forests are very widespread. Raspberry, red elderberry, alpine rose, and Carpathian currant grow in the understory beneath the spruce canopy, while the ground layer features sweet-scented bedstraw (woodruff), wood sorrel, Austrian leopard's-bane, male fern, and occasionally mosses.

Meadow vegetation of this belt develops on the sites of felled beech and spruce forests and is represented by bentgrass (Agrostis), red fescue, and matgrass (Nardus) communities with the participation of red clover, globeflower, pink salsify, mountain violet, arnica, and others. Post-forest meadows harbor a large number of medicinal plants that are harvested in bulk by the local population.

The subalpine belt lies above the upper limit of the upper mountain forest belt, extending up to an altitude of 1800 м. Its characteristic feature is polonynas—high-altitude treeless expanses covered with herbaceous vegetation. In the Carpathians, polonynas and mountain meadows cover more than 100,000 га and are used as pastures and hayfields. The vegetation structure of the polonynas is dominated by matgrass swards (Nardetum) (over 50%). They are particularly widespread on the polonynas of the Rivna, Borzhava, Krasna, Svydovets, Chornohora, and Chyvchyn mountain systems. Smaller areas are covered by tufted hair-grass, fescue, evergreen sedge, alpine bluegrass, and other high-altitude meadows. Flocks of sheep, cattle, and horses graze on them.

At the intersection of the upper forest and subalpine belts lies the krivolesye (Elfin woodland) — beech in the western part and spruce in the eastern part, which takes on a flag-like shape under the unilateral action of wind. In the Eastern Carpathians, quite significant areas are occupied by thickets of dwarf mountain pine (zherep) up to 2–3 m high, which form dense, impassable thickets, protecting the slopes from avalanches and erosion. Along streams on gravelly mountain slopes, green alder (lelechka) settles, forming dense thickets here that play a soil-protecting role. On the poloninas (mountain meadows), thickets of Siberian juniper are very widespread, which, spreading intensively, clutter the pastures.

The alpine belt occupies the highest peaks of the Carpathians — Chornohora, Svydovets, Chivchyn, and is located at an altitude of 1800–2061 m. These peaks are covered with curved-sedge, low-fescue, and other meadows, an essential feature of which is the absence of thickets of Siberian juniper and matgrass (Nardus stricta). On stony soils, bilberry and rhododendron communities are widespread, while on the flat summit plateaus (plakors), there are barren wastelands of three-part rush.

On the ledges of steep cliffs, low-fescue communities have formed, and along long-snow-lying hollows, colorful and picturesque alpine meadows with numerous high-altitude species of diverse forbs.

A characteristic feature of the alpine belt is the vegetation of rocks and stony screes. Here, plants are low-growing, creeping along the soil surface in cushion-like forms (Cardaminopsis neglecta, alpine cerastium), with white-felt pubescence (edelweiss, Carpathian pussytoes, soft cornflower), thereby protecting themselves from the harmful effects of wind and ultraviolet radiation. At the same time, the influx of ultraviolet rays enhances the brightness of the flowers (yellow gentian, Carpathian primrose, narcissus-flowered anemone).

Stony and rocky habitats are home to relict and endemic species — mountain avens (Dryas octopetala), Eastern Carpathian cornflower, Eastern Carpathian rhododendron, twinflower (Linnaea borealis), alpine bartsia, and alpine aster.

There are few bogs in the Carpathians; these are predominantly transitional and raised bogs, convex, with poor sphagnum and herb-sphagnum cover and spruce sparse woodland.

The weed vegetation of the foothill and mountainous regions of the Carpathians is quite specific; it includes hairy galinsoga, field chickweed, yellow foxtail, green foxtail, common barnyard grass, common toadflax, Tournefort's speedwell, hair-like hawksbeard, dodder (Cuscuta campestris and Cuscuta epithymum), etc..

Foothill and Mountainous Regions of Crimea

South of the Steppe lies the zone of the foothill and mountainous regions of Crimea, the northern boundary of which runs past Sevastopol, Bakhchisaray, Simferopol, Bilohirsk, and Stary Krym. The vegetation structure clearly exhibits vertical zonality, or altitudinal zonation, which is determined by altitude above sea level and the Specific features of the southern and northern macro-slopes (Fig. 117).

Vegetation of the northern macro-slope. In geomorphology, three mountain ridges are distinguished, each with its own vegetation features. From north to south, the steppe smoothly transitions into the foothills of the third ridge (150–200 m), which is well cultivated, with only lands unsuitable for development covered by natural vegetation. The valley (3–5 km) separating the third ridge from the second (400–600 m) is also intensively cultivated, as is the third ridge, occupied by vineyards, cereal and industrial crops alternating with steppe, meadow, and forest vegetation. Similar to this is the vegetation of the valley (15–20 km) separating the second ridge from the Main Coastal Ridge, which is covered with natural vegetation.

The climate exhibits Mediterranean features, which significantly affects the character of the vegetation. The average annual temperature in the foothills of the Southern Coast of Crimea is 11–12 °C, and in the middle zone, it is 8–10 °C. The annual precipitation amount is 350–600 mm in the foothills, 550–750 mm in the middle zone, and 700–900 mm in the high mountains.

There are differences in the plant cover of the southern and northern macro-slopes, which is associated with the distribution of precipitation, temperatures, and the Influence of the Black Sea and, in part, the Sea of Azov. In the plant cover of the northern macro-slope, the forest-steppe zone, the oak forest zone, and the beech forest zone are distinguished.

The forest-steppe zone encompasses the foothills of the third, second, and partly the first ridges, as well as the valleys separating them. The composition of natural vegetation is dominated by communities of meadow-steppe and forest phytocoenoses. A characteristic feature of forest vegetation is the widespread occurrence of coppice woods formed by downy oak, sessile oak, and pedunculate oak. These coppice woods arose in place of felled high-forest stands. Today's coppice woods are of stump origin and 5–8 m tall. Their companions are wild pear, white elm, wild service tree (Sorbus torminalis). The understory features European cornel, smoke bush, oriental hornbeam, steppe blackthorn, while the herbaceous cover includes three-lobed toothwort, rocky false-brome (Brachypodium rupestre), Danaë racemosa, purple gromwell, etc.

Steppe vegetation is represented by feather grass-forb and fescue-feather grass communities featuring beautiful feather grass (Stipa pulcherrima), sheep's fescue (Festuca sulcata), slender koeleria, low sedge, narrow-leaved peony, and asphodeline.

The oak forest zone is located at an altitude of 300–700 m. Here, two sub-belts of oak forests are distinguished: the lower one of downy oak and the upper one of sessile oak, which In the second tier includes oriental hornbeam and, in places, high juniper.

The beech forest zone represents the upper forest belt and is formed by the Crimean beech. Beech forests develop on northern slopes starting from an altitude of 400–600 m a.s.l. and reach the yailas (mountain meadows). On well-moistened brown forest soils, their stands reach site index classes I–II. Beneath the dense canopy of crowns, a limited number of species grow — multi-flowered mercury (Mercurialis perennis), five-leafed bittercress, cowslip, sweet woodruff, grove bluegrass, fragrant solomon's seal, etc.

Vegetation of the southern macro-slope. Compared to the northern macro-slope, the vegetation of the southern macro-slope is more xerophytic. The vegetation structure of the southern macro-slope includes A number of belts.

The lower forest-steppe belt of the southern macro-slope is divided into three distinct sub-belts: a) the coastal sub-belt, where soils are absent and halophytic communities are formed; b) the pseudomaquis sub-belt, dominated by evergreen deciduous trees or shrubs; c) the shiblyak sub-belt, consisting of deciduous hemixerophytic communities.

The coastal sub-belt. The narrow (from 5–7 to 50–60 m wide) sandy-pebble coastal strip (beach areas) is of no special botanical interest, yet salt-tolerant species grow here: rock samphire (Crithmum maritimum), Pontic sea kale, sea spurge, Black Sea searocket, and sea knotgrass.

The pseudomaquis sub-belt. Its landscape is very characteristic of pyramidal cypress and tree-like junipers, which create groves of unique beauty. In parks, gardens, and along the foothill slopes grow Fortune's windmill palm (Trachycarpus fortunei), Himalayan and Lebanon cedars, Italian stone pine (pinia), coast redwood, southern magnolia, small-fruited madrone, giant sequoia, Spanish broom, etc., which stand out vividly against the backdrop of gardens, vineyards, and natural vegetation.

The shiblyak sub-belt occupies the stony slopes of the Black Sea coastal strip, alternating with plots of fruit, berry, industrial, and vegetable crops. This is a belt of shrub communities, low-trunk oak and oak-juniper forests known as "shiblyak". Its upper boundary runs at an altitude of 350–400 m above sea level. In a botanical-geographical sense, the southern coast of Crimea is of exceptional interest, striking with the richness of its flora and vegetation, which are very similar to those of the Mediterranean countries.

The shiblyak coastal strip is characterized by juniper woodlands and phryganoid communities of ephemeral and ephemeroid grasses (Aegilops ovata, Aegilops triuncialis, bulbous barley, hare barley, long-leaved boundweed), most of which have an ancient Mediterranean range.

In shiblyak communities, three groups can be distinguished: 1. The dominant species is downy oak. 2. High juniper and red juniper join the downy oak as co-dominants. 3. The main species are downy oak and turpentine tree (Pistacia mutica).

An essential feature of the southern coast shiblyak is the significant presence of evergreen or semi-evergreen plants — smoke bush, Sicilian sumac, rose species, steppe blackthorn, boxthorn, red firethorn, Pontic butcher's broom, shrubby jasmine, oriental hornbeam, etc.. An original evergreen species grows here — the small-fruited madrone, which completely sheds its bark during the summer, exposing a pistachio-colored trunk.

Parks and gardens are an integral part of the landscape of the Southern Coast of Crimea. Crimean parks originated in the early 19th century at the summer residences of tsars and aristocrats. The magnificent Alupka Landscape Park covers an area of about 40 ha. Italian and native pines, Himalayan and Lebanon cedars, plane trees, cypresses, palms, etc. grow here.

The vast 127-ha Livadia Park landscape features Crimean and Pitsunda pines, strawberry trees, downy oaks, tree junipers, and exotics such as Himalayan, Lebanon, and Atlas cedars. The cedars are over 100 years old, standing about 25 м tall with a trunk diameter exceeding one meter.

The shiblyak zone is home to the famous Nikita Botanical Garden. Most foreign plant species currently cultivated in Crimea as ornamental plants, as well as fruit and essential oil crops (such as rose, lavender, clary sage, rockrose, bergamot bee balm, mountain mint, and many others), first underwent primary Introduction right here at the Nikita Botanical Garden.

The middle forest belt of the southern macro-slope is divided into two subbelts: the Crimean pine (Pallas pine) and the sessile oak. The Crimean pine subbelt occupies the lower section and extends at an altitude of 250—900 м above sea level. On limestone outcrops, the crown of the Crimean pine assumes a horizontal shape. Up to an altitude of 450 м, dry pine forests are widespread, transitioning higher up to fresh pine forests, which above 700 м give way to mixed pine forests (subor). Here, the second canopy layer is formed by downy and sessile oaks. The herbaceous layer abounds in almond spurge, wood germander, and Canary clover. The sessile oak subbelt, located at an altitude of 600—800 м above sea level, is formed by sessile oak forests covering up to 40% of the zone's forested area. Co-dominants include Crimean pine, common and Oriental hornbeams, downy oak, and European ash. The oak woodlands feature a lush understory and a sparse herbaceous layer composed of Crimean forest and meadow xerophytic species.

The upper forest belt is divided into two subbelts: boreal pine forests dominated by Pallas pine (Sosnowsky pine) and nemoral beech forests dominated by Crimean beech or Oriental beech.

The subbelt of boreal pine forests is characteristic of the zone adjacent to the yaylas. The Pallas pine that forms this subbelt features a pyramidal crown and light, brownish-black trunks. Optimal conditions for its development occur at an altitude of 700—1000 м, where fresh pine forests form stands 20—24 м tall, whereas with the deterioration of soil and climatic conditions (above 1000 and up to 1200 м), their height reaches 16—20 м. Numerous xerophytic species grow beneath the forest canopy, including false brome, barren false brome, bristly couch grass, and others.

Meadow vegetation is sparse in mountainous Crimea, represented by graminoid and graminoid-forb communities dominated by heath false-brome, meadow fescue, tall oat-grass, Cappadocian brome, accompanied by legumes and a rich variety of xerophytic herbs.

At the mountain summits, the forest gives way to thickets of Cossack and dwarf junipers.

The Yayla Belt. Yaylas are the treeless, rolling summits of the First Crimean Ridge, covered by steppes, meadow steppes, and steppified meadows. They stretch for 120 км from southwest to northeast as distinct massifs—Ai-Petri, Demerdzhi, Chatyr-Dag, Karabi, and others. Mountain steppes on the yaylas are formed by Brauner's feather grass, rock-loving feather grass, hair-like feather grass, Cappadocian brome, Caille's fescue, yellow asphodel, Crimean thyme, Crimean germander, Steven's rock-rose, and other steppe species with a broad geographic range.

Up to 25% of the yayla territory consists of meadow steppes and steppified meadows. Communities of sheep's fescue and sedges are very common across all yaylas, with low sedge making up about 60—80% of the phytocenoses. They frequently intermingle with already familiar species of mountain and lowland steppes.

The vegetation of rocks and stony screes is unique, picturesque, and includes rare and endemic species of the region and Ukraine. Typical representatives include Bieberstein's chickweed, mountain speedwell, gorgeous feather grass, Oriental cornflower, pointed whitlow-grass, Oriental rock-rose, yellow asphodel, Crimean peony, Crimean foxtail lily, and Crimean orchid.

Weed vegetation includes numerous noxious agricultural weeds frequently found in vineyards, as well as grain, industrial, and other crop fields—such as Canada thistle, humble cornflower, spreading cornflower, Oriental hedge mustard, mountain ironwort, Bermuda grass, buffalorobert, Tartar sow-thistle, Oriental beggarticks, and others.

Among the various types of Crimean vegetation, many species possess medicinal properties and are suitable for harvesting raw medicinal materials. These include species such as Syrian rue, spiny Jerusalem sage, fragrant Solomon's seal, Sicilian sumac, pheasant's eye, and particularly various species of thyme, hawthorn, rose hips, pine, and oak, among others.