Quantitative characteristics of the flora. Course work flora as a component of biological diversity General characteristics of flora

So, flora and vegetation are two different components of the vegetation cover.

The flora of our Motherland has more than 18,000 species. All this huge variety of plants is distributed into 160 families. The richest species in our family are the Asteraceae, cereals, and legumes, each of which contains several thousand species. There are relatively many species in families such as Rosaceae, Cruciferae, Ranunculaceae, Dianthus, and Sedge. Representatives of these families can be found everywhere - from the tundra to the desert, from the western to the eastern borders of the country, from the plains to the highlands.

The geographical distribution of individual plant species is very different. Some of them are found only in a limited area, sometimes very small. Thus, Semenov fir grows exclusively in the mountains of Kyrgyzstan, and Crimean peony - only in the southern part of Crimea. However, many species have a wider distribution; they are not confined only to a limited area. Finally, there are also species that are very widespread and are found throughout most of the territory of the Soviet Union. An example would be trees familiar to everyone - Scots pine, aspen, birch.

The area of ​​natural distribution of a plant on the earth's surface is called its habitat. If the range of a particular species is relatively small and this species is found only in one specific area of ​​the globe, then this species is called endemic for the corresponding area. This is what they say about endemic plants, or, in other words, endemics, of the Caucasus, Carpathians, Central Asia, etc.

The flora of our country contains many endemic species. There are especially many of them in the flora of high mountain belts.

Among the plants of the domestic flora, the so-called relics are of great interest - ancient species that have survived to our time from geological eras more or less distant from modern times. The “oldest” relics in our country are plants preserved from the Tertiary period (2 - 65 million years ago). These include, for example, Pontic rhododendron - a large evergreen shrub growing in the coastal regions of Georgia (Colchis); ironwood forming forests in the mountains of Azerbaijan (in Talysh); Amur velvet - a tree common in our Far East (Primorye), and others. On the territory of the Soviet Union there are several regions where similar plants are found, the most important of them: Western Transcaucasia, or Colchis, the extreme south of Azerbaijan, or Talysh, our Far East. Relicts of the Tertiary period are quite heat-loving plants, so they survived in our country only where the climate remained quite warm for a long time. In other regions of the Soviet Union, plants of this type died in Quaternary period due to the onset of a glacier or a sharp climate change.

Relict plants, like endemic plants, are of great scientific value. Many of them need protection.

The concept of flora…………………………………………………………….3-8
Contribution of flora to overall biodiversity………………………..9-10
Characteristics of the flora of Bashkortostan……………………….11-39
Protection of biological diversity and flora

as its component…………………………………………. 39-47

Conclusion…………………………………………………………….….48

Conclusions…………………………………………………………………….49

Introduction.
Preserving biodiversity is one of the key problems in building a society with sustainable development.The most important component of biodiversity is flora as a set of plant species growing on certain territory. Flora serves as the basis for the formation of not only vegetation, but also ecosystems. In accordance with the well-known ecological principle “diversity begets diversity,” flora predetermines the composition of heterotrophic components of ecosystems. For this reason, the study of flora, its rational use and protection are the most important components of a broad program for the conservation of biodiversity as an exhaustible resource.
There is undeniable progress in protecting biodiversity around the world. A number of important international documents have been adopted and are being implemented, such as the “Concept on the Protection of Biological Diversity” (Rio de Janeiro, 1992), the “Pan-European Strategy for the Protection of Biological Diversity” (1996), etc. International cooperation in environmental issues is expanding and intensifying activities of international organizations - UNESCO, World Conservation Union (IUCN), World Wildlife Fund (WWF). The WWF office operates in the Republic of Bashkortostan and makes a significant contribution to the protection of flora.
IN last years Increasing attention is being paid to the protection of biodiversity in Russia and Bashkortostan. The need to preserve biodiversity is reflected in such documents as the “Concept of the Russian Federation’s transition to sustainable development” (1996), the federal law “On environmental protection (2002), the “Ecological Doctrine of Russia” (2002), the law “On specially protected natural territories of the Republic of Bashkortostan" (1995), republican comprehensive program "Ecology and natural resources of the Republic of Bashkortostan for 2004-2010", "Concept for the development of a system of protected natural areas in the Republic of Bashkortostan" (2003).
Purpose of the work: to talk about the uniqueness of the flora as a hotbed of biodiversity of global significance, economic value, state of use and protection; characterize the flora of Bashkortostan.

I. The concept of flora.
Flora (in botany, lat. flora) - a historically established set of plant species distributed in a certain territory at the present time or in past geological eras. Houseplants, plants in greenhouses, etc. are not included in the flora.
The name of the term comes from the name of the Roman goddess of flowers and spring blossoms, Flora (lat. Flora).
In practice, the expression “Flora of a certain territory” often means not all plants of a given territory, but only vascular plants (Tracheophyta).
Flora should be distinguished from vegetation– a collection of different plant communities. For example, in the flora of the temperate zone of the Northern Hemisphere, species of the families of willows, sedges, grasses, ranunculaceae, and Asteraceae are richly represented; from conifers - pine and cypress; and in vegetation - plant communities of tundra, taiga, steppe, etc.
Historically, the development of flora is directly determined by the processes of speciation, the displacement of some plant species by others, plant migrations, their extinction, etc.
Each flora has specific properties - the diversity of its constituent species (richness of flora), age, degree of autochthony, endemism. Differences between the floras of certain territories are explained primarily by the geological history of each region, as well as differences in orographic, soil, and especially climatic conditions.

Flora analysis methods:

geographical analysis - division of flora by geographical distribution; identification of the proportion of endemics;
genetic analysis (from Greek genesis “origin, emergence”) - division of flora according to criteria geographical origin and settlement history;
botanical-geographical analysis - establishing connections between a given flora and other floras;
ecological and phytocenological analysis - division of flora by growing conditions, by types of vegetation;
age analysis - division of the flora into progressive (young in time of appearance), conservative and relict elements;
systematic structure analysis - comparative analysis of the quantitative and qualitative characteristics of various systematic groups that make up the given flora.

Flora typification

Flora of specialized groups
Collections of plant taxa, covering specialized groups of plants, have corresponding specialized names:
Algoflora- algae flora.
Bryoflora- moss flora.
Dendroflora, or arboriflora- flora of woody plants.
Three more terms appeared before these groups of organisms were no longer classified as plants:
Lichen flora- lichen flora.
Mycoflora- mushroom flora.
Mixoflora- flora of myxomycetes (slime molds)

Flora of the territories
From the point of view of the nature of the territories under consideration, they are distinguished:
Flora of the Earth as a whole
Flora of continents and their parts
Flora of individual natural formations(islands, peninsulas, mountain systems)
Flora of countries, regions, states and other administrative entities

Flora according to external conditions
According to the criterion of external conditions, the territories under consideration are distinguished:
Flora of chernozem and other soil types
Flora of swamps and other special areas of the earth's surface
Flora of rivers, lakes and other fresh water bodies
Flora of the seas and oceans

Basic approaches to the study of floras.

Flora as a set of species of a certain territory is formed under the influence of natural and anthropogenic factors. For this reason, studying its composition is one of the tasks of environmental monitoring.

Regional floras.
Most often, regional floras are studied within the boundaries administrative units(republic, administrative region, city or rural locality). This is the most traditional type of floristic research, the most important task that allows for one of the options for biomonitoring - monitoring the state of biological diversity of plants in the region.
The result of the study of regional flora is a complete list of plant species with an assessment of their distribution. This makes it possible to identify rare species and compile the “Red Book”. With periodic repeated examinations, a tendency for changes in the flora under the influence of humans is revealed, primarily adventization, i.e. an increase in the proportion of alien species and a decrease in floristic diversity.
The study of regional floras is necessary for the geobotanical study of vegetation, the assessment of botanical resources and the development of a system for the protection of plant biodiversity in the region.

Specific floras.
Unlike regional floras, which are identified for any territory, regardless of the diversity of environmental conditions (they may include different natural zones, plains and mountains, etc.), specific floras are identified for ecologically homogeneous territories (with one type of climate, one type of geomorphological structure of the surface, one type of predominant vegetation). For example, the flora of the Baymak or Abzelilovsky district, which include lowland and mountainous territories, cannot be considered as specific floras. The flora of the steppe part of the Bashkir Trans-Urals, the flora of the southern part of the mountain forest zone of Bashkortostan, etc. can be considered as specific.
The identification of specific floras is carried out over a fairly large area, within which the influence of the natural complex and human activity on the composition of plant species is fully manifested. This value can vary from 100 km? in the Arctic up to 1000 km? in the tropics.

Partial floras.
The concept of “partial flora” was proposed by B.A. Yurtsev within the framework of the method of specific floras, but this concept is also used in the study of regional floras. Partial flora is understood as the flora of a certain type of habitat and, accordingly, a certain type of plant community associated with it (in this case, the partial flora is called coenoflora). Thus, partial floras of reservoirs and coastal-aquatic habitats, lowland, transitional and raised swamps, southern steppe rocky slopes, post-forest meadows, wastelands, and fields are distinguished. When studying the floras of populated areas, partial floras of vegetable gardens, courtyards, trampled habitats, ditches, dung heaps, etc. are identified.

Assessing gamma diversity.
Gamma diversity is a form of biological diversity, defined as the number of plant species in a landscape or geographic area. It is synonymous with regional flora.
Gamma diversity depends on the area of ​​the study area and is formed as a result of the interaction of two forms of diversity:
Alpha - diversity - species diversity of communities;
Beta diversity - diversity of communities.
These two indicators are related nonlinearly, because In different communities, species richness is different, however, it is obvious that the richer the community is in species and the higher the diversity of these communities, the higher the gamma diversity. Naturally, both components of gamma diversity depend on the characteristics of climate and topography. On the flat territory of the desert zone, the values ​​of alpha and beta diversity and, accordingly, gamma diversity will be minimal. In the temperate zone, with a complex topography that combines species-rich communities of steppes, meadows, forests, and, in addition, there are coastal-aquatic and aquatic communities and ruderal and segetal communities associated with human influence, gamma diversity will be high.

Analysis of flora composition.
Any flora (regional, specific, partial) consists of species that differ in a significant number of parameters: systematic affiliation, life form, geographical characteristics, biological characteristics. For this reason, a qualitative analysis of the composition of the flora (compilation of various spectra) is one of the mandatory sections of any floristic study.
Flora analysis includes compiling spectra based on the following parameters.

Systematic composition.
The representation of different families is analyzed, special attention is paid to the first 10 families, which are called leading. The degree of their participation in the flora and the complex of soil-climatic factors, and the history and current state of the flora under human influence. Thus, for the natural flora of the temperate zone, to which Bashkortostan belongs, the leading families (Table 1) are characterized by the participation of Asteraceae, grasses, roses, sedges, legumes, cruciferous plants, cloves, noricaceae, etc. With increasing human influence (synanthropization and adventivization flora) the proportion of species from the families Chenopodiaceae and Cruciferae is increasing.
When analyzing the systematic composition of the flora, such indicators as the average number of species in a genus, the average number of genera in a family, the average number of species in a family that can receive an evolutionary interpretation are used (the more genera in families, the older they are; the more species in genera , on the contrary, they reflect later stages of evolution).

Spectrum of life forms.
This spectrum also reflects the diversity of environmental conditions in which the studied flora was formed. So, in humid tropical forests Phanerophytes predominate; in the forests of the temperate zone, which includes Bashkortostan, despite the fact that phanerophytes dominate, hemicryptophytes predominate in the flora. In the steppes and meadows there are few phanerophytes and the predominance of hemicryptophytes is more complete. Therophytes predominate in deserts. The significant participation of therophytes indicates synanthropization of the environment.

Synanthropicity of the flora.
Assessing the replenishment of flora by adventitious plants is an informative method of biomonitoring, because the proportion of alien plants is directly related to the intensity of vegetation transformation by humans.
This version of the analysis includes the compilation of spectra for the proportional participation of different groups of synanthropic species from among local species that have adapted to intense human influence, as well as adventive species.

Phytosociological spectrum.
The most promising way to compare floras (especially specific ones) is to evaluate the modern ecological structure of the flora and the degree of its adventivization.
By comparing the share of species of different orders or classes of vegetation, one can obtain the most integrated information about the geography, ecology and anthropogenic disturbance of the studied flora.

Contribution of flora to overall biodiversity.

Characteristics of the flora of Bashkortostan.

According to the latest data, the flora of vascular plants of Bashkortostan includes 1730 species, bryoflora - 405 species, lichen biota - 400 species. The floristic diversity of different regions of Bashkortostan varies. Areas with a high concentration of species are the Iremel and Yaman-Tau mountains; shikhans (mountains - outliers) Tratau, Yuraktau, Tastuba, Balkantau, Yaryshtau, Susaktau; ridges Mashak, Zigalga, Irendyk, Krykty, Kraka, Shaitan - Tau; valleys of the rivers Belaya, Inzer, Ural, Sakmara, Zilim, Nugush, Uryuk, B. and M. Ik, Zilair, Fortress Zilair, Tanalyk; lakes Yakty - Kul, Urgun, Talkas, Karagaily; swamps Tyulyukskoye, Tygynskoye, Zhuravlinoe, Septinskoye, Arkaulovskoye, Lagerevskoye, etc.
The formation of high floristic diversity is associated with the influence of a number of natural, historical and anthropogenic factors.

Relief. The Southern Urals mountain system is located on the territory of Bashkortostan. Due to the vertical zonation, mountainous terrain allows different biomes to be combined in a limited area - from mountain tundras and boreal forests to deciduous forests and steppes.

History of flora. The enrichment of the flora was facilitated by the complex history of the territory of Bashkortostan, especially its mountainous part. It contains many relics that reflect the history of the region over the past 1.5 million years, when climate cooling and warming alternated in the Pleistocene and Holocene.

Geographical location: the junction of Europe and Asia. The position of Bashkortostan at the junction of Europe and Asia has led to the combination of Siberian and European species in communities (the formation of an ecotone effect on a geographic scale). Thus, in the forests of the Southern Urals, typical European species are combined, such as amazing violet, lungwort, woodland grass, foxglove grandiflora, fragrant bedstraw, and species of the Siberian range - Siberian adonis, northern aconite, Gmelin's rank, unripe lance-shaped, etc.

Latitudinal zone. The location at the junction of forest and steppe zones gave rise to widespread hemiboreal forests with pine dominating the tree layer (with the participation of birch, larch and aspen). These are the richest forests in the Southern Urals, which is also due to the ecotone effect. With the undeniable dominance of boreal species in the herbage (reed grass, northern aconite, lily-leaved bellweed), nemoral and subnemoral species are common in these forests: male shield grass, spreading boron, stiff-leaved chickweed, common gooseberry, amazing violet, etc. A significant role is played by meadow, meadow- steppe and steppe species, such as: steppe cherry, chiliga, Russian broom, oregano, etc.

Human influence. During the period of sustainable environmental management, characteristic of the Bashkirs before the reform of 1861, anthropogenic factors did not cause significant damage to BR and other renewable resources. Moreover, some forms of human influence were a factor that increased BR. Thus, it was thanks to humans that species-rich communities of lowland and mountain post-forest meadows were formed. After the disappearance of natural large steppe phytophages (saiga, tarpan), it was the school horse breeding of the Bashkirs that was the main factor in the preservation of the steppe biome. Schools of horses constantly moved across the steppe landscapes, ensuring uniform grazing of phytomass. In addition, horses have the least detrimental effect on steppe communities: hoof pressure is minimal, and a wide diet contributes to uniform consumption of grass.

Systematic composition of the flora.

Table 1. Representation of families of higher spores and gymnosperms in the flora of Bashkortostan.

Resource characteristic

Let's consider the main groups of useful plants of the flora of Bashkortostan: forage, medicinal, melliferous, food, as well as “anti-useful” plants - poisonous, many of which, however, are used as medicines.

Forage plants
Forage plants form the basis of hayfields and pastures. Their number in Bashkortostan is at least 500 species. Forage plants are divided into agrobotanical groups: cereals, legumes, forbs, sedges, wormwood. In turn, these groups can be divided into steppe and meadow.
Cereals
Steppe: Agropyron pectinatum (crested wheatgrass), Festuca pseudovina (fescue grass), F. Valesiaca (Welsh grass), Koeleria cristata (crested grass), Poa transbaicalica (steppe bluegrass), Stipa capillata (feather grass), S. Lessingiana ( K. Lessing), S. Pennata (K. pinnate), S. Sareptana (K. Sarepta), S. Tirsa (K. angustifolia), S. Zalesskii (K. Zalesski).
Meadow: Agrostis gigantean (giant bentgrass), A. Stolonifera (shoot-forming species), Alopecurus pratensis (meadow foxtail), Bromopsis inermis (awnless brome), Calamagrostis epigeios (ground reed grass), Dactylis glomerata (urchin grass), Elytrigia repens (wheatgrass) creeping), Festuca pratensis (meadow fescue), Phalaroides arundinacea (reed grass), Phleum pratensis (meadow timothy grass), Poa angustifolia (angustifolia bluegrass), P. pratensis (meadow grass).
Legumes
Steppe: Astragalus danicus (Danish astragalus), Medicago romanica (Romanian alfalfa), Melilotus albus (white sweet clover), M. Officinalis (officinalis), Onobrychis arenaria (sandy sainfoin), Trifolium montanum (mountain clover), Vicia tenuifolia (pea narrow-leaved).
Meadow: Lathyrus pratensis (meadow chin), Medicago lupulina (hop alfalfa), Trifolium hybridum (hybrid clover), T. pratense (meadow pea), T. repens (creeping pea), Vicia cracca (mouse pea).
Forbs
Steppe: Achillea millefolium (common yarrow), Centaurea scabiosa (cornflower), Filipendula vulgaris (meadowsweet), Galium verum (bedstraw), S. stepposa (steppe sage), Serratula coronata (crowned cornflower), Thalictrum minus (small cornflower ).
Meadow: Achillea millefolium (common yarrow), Carum carvi (common cumin), Filipendula ulmaria (meadowsweet), Fragaria viridis (green strawberry), Geranium pratensis (meadow geranium), Heracleum sibiricum (Siberian hogweed), Leucanthemum vulgare (common cornflower) , Pimpinella saxifrage (saxifrage), Plantago maior (great plantain), P. media (medium), Polygonum aviculare (bird knotweed), P. bistorta (snake), Potentilla anserina (cinquefoil), Prunella vulgaris ( common blackhead), Ranunculus polyanthemos (multifloral buttercup), Rumex confertus (horse sorrel), R. thyrsiflorus (pyramidal sorrel), Sanguisorba officinalis (burnet), Tanacetum vulgare (common tansy), Taraxacum officinale (dandelion), Tragopogon orientalis ( eastern salsify).
Meadow-marsh: Caltha palustris (marsh marigold), Lythrum salicaria (willow loosestrife), Symphytun officinale (comfrey), Trollius europaeus (European bathhouse).
Sedges
The main part of sedge species is associated with wet and swampy meadows. Sedges are poorly eaten on pastures, and sedge hay is considered of little value. The feed value of sedge forage increases when it is ensiled.
The most common in Bashkortostan on waterlogged soils are Carex acuta (sharp sedge), C. Acutiformis (pointed sedge), C. cespitosa (turfy sedge), C. juncella (sedge sedge). C. pediformis (stop-shaped), C. Praecox (early), C. muricata (spiny) and others are common in steppe meadows and steppes.
Among the saline species, C. asparatilis (rough) and C. distans (distanced) are of greatest nutritional importance.
Wormwood
Artemisia (genus Artemisia) form the basis of semi-desert communities, which do not exist in Bashkortostan. However, some species of wormwood are found in disturbed meadow and ruderal communities (A. Absinthium - wormwood, sieversiana - Siversa village, A. vulgaris - common wormwood), however, most of the wormwood is associated with steppe grass stands, with a special role played by Austrian wormwood ( A. austriaca), dominant in the steppes with heavy grazing. All wormwoods are poorly eaten in pastures and hay.
Medicinal plants

The great medieval physician Paracelsus said that “the whole world is a pharmacy, and the Almighty is a pharmacist.” Currently, the flora of Bashkortostan includes about 120 species used in scientific medicine, and more than 200 species used in folk medicine. List of medicinal plants of the flora of Bashkortostan used in scientific medicine:
Achillea millefolium (common yarrow)
Adonis vernalis (Spring adonis)
Alnus incana (Grey alder)
Althaea officinalis (Althaea officinalis)
Angelica archangelica (Angelica officinalis)
Artemisia absinthium (Wormwood)
Betula pendula (Warty birch)
Bidens tripartita (Tripartite series)
Bupleurum aureum
Capsella bursa – pastoris (Shepherd's purse)
Carum carvi (Cumin)
Centaurea cyanus (Blue Cornflower)
Centaurium erythraea (Common centaury)
Chamerion angustifolium (Ivan – narrow-leaved tea)
Chamomilla recutita (Chamomile)
Chamomilla suaveolens (Chamomile)
Chelidonium majus (Great celandine)
Convallaria majalis (May lily of the valley)
Crataegus sanguinea (Blood red hawthorn)
Datura stramonium (Datura stramonium)
Delphinium elatum (Tall Larkspur)
Digitalis grandiflora (Foxglove grandiflora)
Dryopteris filix – mas (Male fern)
Echinops sphaerocephalus (Echinops sphaerocephalus)
Elytrigia repens (Creeping wheatgrass)
Erysimum diffusum (Erysimum diffusum)
Equisetum arvense (Horsetail)
Fragaria vesca (Wild strawberry)
Frangula alnus (Break buckthorn)
Glycyrrhiza korshinskyi (Korzhinsky's licorice; the species is included in the Red Book of the Republic of Belarus)
Gnaphalium rossicum (Russian dryweed)
Humulus lupulus (Common hop)
Huperzia selago (Common sheep)
Hyoscyamus niger (Black henbane)
Hypericum perforatum (St. John's wort)
Inula helenium (Elecampane)
Juniperus communis (Common juniper)
Leonurus quinquelobatus (Moonwort five-lobed)
Lycopodium clavatum (Moss moss)
Melilotus officinalis (Melilot officinalis)
Menyanthes trifoliate (Trifoliate watch)
Nuphar lutea (Yellow egg pod)
Origanum vulgare (Oregano)
Oxycoccus palustris (Swamp cranberry)
Padus avium (Bird cherry)
Plantago major
Pinus sylvestris (Scots pine)
Polemonium caeruleum (Blue cyanosis)
Polygonum aviculare (Knotweed)
Polygonum bistorta (Snake knotweed)
Polygonum hydropiper (Water pepper)
Polygonum persicaria (Knotweed)
Potentilla erecta (Potentilla erecta)
Quercus robur (English oak)
Rhamnus cathartica (Gester laxative)
Ribes nigrum (Black currant)
Rosa majalis (May rosehip)
Rubus idaeus (Common raspberry)
Rumex confertus (Horse sorrel)
Sanguisorba officinalis (Burnet)
Sorbus aucuparia (Rowan)
Tanacetum vulgare (Common tansy)
Taraxacum officinale (Dandelion)
Thermopsis lanceolata (Thermopsis lanceolata)
Thymus serpyllum (Creeping thyme)
Tilia cordata (Little Leaf Linden)
Tussilago farfara (Mother and stepmother)
Urtica dioica (Nettle)
Vaccinium vitis – idaea (Lingonberry)
Valeriana officinalis (Valerian officinalis)
Veratrum lobelianum (Lobel's hellebore)
Viburnum opulus (Viburnum)

Honey plants
Beekeeping is a traditional branch of the Bashkir economy, and the main food supply for bees consists of plants of wild flora, which determines the high commercial quality of Bashkir honey. Honey plants include plants from which bees collect nectar and pollen. Bees get sugar (carbohydrates) from nectar, and protein and fat from pollen.
All plants, including nectar bearers, provide pollen, but wind-pollinated plants are especially rich in it. Among them: tree and shrub species from the genera Alnus (alder), Betula (birch), Corylus (hazel), Populus (poplar), Salix (willow), Quercus (oak), Ulmus (elm); herbs – Cannabis ruderalis (hemp), Humulus lupulus (hops), species of the genera Amaranthus (sorrel), Artemisia (wormwood), Bidens (chain), Chenopodium (pigweed), Rumex (sorrel), Typha (cattail) and others.

E.N. Klobukova - Alisova identifies the following groups of honey plants.

Poisonous plants
Some of the flora of Bashkortostan is represented by poisonous plants, and many of the plant poisons in low doses are used as medicines. The most important poisonous plants are the following: Aconitum septentrionale (tall fighter), Actaea spicata (spike-shaped crowberry), Adonis vernalis (spring adonis), Anemonoides altaica (Altai anemone), A. ranunculoides (buttercup), Chelidonium majus (greater celandine), Cicuta virosa (poisonous plant, this is the most poisonous plant), Conium maculatum (spotted hemlock), Convallaria majalis (May lily of the valley), Daphne mezereum (wolf's bast), Equisetum palustre (swamp horsetail), E. pratense (meadow horsetail), E fluviatile (x. river), E. sylvaticum (x. forest), Hyoscyamus niger (black henbane), Juniperus Sabina (Cossack juniper), Paris quadrifolia (four-leaved crow's eye)
Brief description of natural areas of the Republic of Bashkortostan

BASHKIR CIS-URALS
1. Kama-Tanypsky region of broad-leaved, broad-leaved-dark-coniferous and pine forests
The undulating plain between the rivers. Kama, Belaya and Bystry Tanyp. The climate is moderately warm, well-humidified. Gray and light gray forest, soddy-podzolic and floodplain soils predominate.
Human influence. The area is heavily developed and densely populated. Factors of threat to biodiversity and deterioration of the ecological situation: cutting down the last fragments of indigenous forest types and replacing them with artificial plantings; air pollution from industrial emissions and acid rain; pollution (soil, atmosphere, water) during oil production; soil erosion; overgrazing; destruction of natural vegetation during the preparation of the bed of the Nizhnekamsk reservoir; unregulated recreation in coniferous forests (Nikolo-Berezovskoe district); anthropogenic swamping of forests, etc.
Vegetation, flora. In the past, broad-leaved-dark coniferous (linden-fir-spruce, oak-fir-spruce), broad-leaved (linden-birch, linden-oak, etc.) and, along the sandy river terraces, broad-leaved pine forests dominated, which, at present , were mostly replaced by secondary forests, meadows, artificial plantings and farmland. The main forest-forming species: spruce, fir, pine, birch, linden, oak, aspen. The vast swamp areas that existed in the past (Katay, Cherlak-Saz, etc.) in the Pribelskaya Lowland have been destroyed or severely disturbed by land reclamation. The flora is mixed, boreal-nemoral, relatively poor. Relict and endemic species are almost absent.
Objectives of biodiversity protection. Key areas with rich biodiversity: river valleys and their terraces (the Kama, Belaya, Bystry Tanyp, Piz, Bui, etc. rivers), the Karmanovskoye reservoir, the green zone of Neftekamsk, restricted forest strips along river banks, preserved and restored island indigenous types of forests and swamps. The level of protection is low: 1 reserve and 6 natural monuments.
Main objects of protection: standard and rare types of forests (broad-leaved-dark-coniferous and pine, southern taiga pine forests, green moss and lichen, pine-larch-linden - on sandy soils, spruce-white moss forests, etc.), preserved and potentially restored swamps (sphagnum pine, sedge-hypnum, etc. .), rare species of plants (Siberian iris, sandy astragalus, perennial forest grass, wild rosemary, marsh cranberry, grasshopper, etc.). Species requiring reintroduction or restoration of habitats: narrow-cupped carnation, anomalous peony, slender cotton grass.
2. Zabelsky region of broad-leaved forests
General characteristics of the natural complex. Gently undulating and hilly plains of Pribelye. Karst landforms are widely represented. The climate is moderately warm, well-humidified. To one degree or another, podzolized gray forest soils predominate.
Human influence. The area is heavily developed and densely populated. Factors that threaten biodiversity and deteriorate the ecological situation: logging of indigenous forests, overgrazing, soil erosion, river pollution. White industrial wastewater, air pollution, destruction of swamps, unregulated recreation around cities, poaching, urbanization, etc.
Vegetation, flora. In the past, broad-leaved forests (oak, linden, maple, elm) dominated, which have now largely given way to secondary forests (linden, birch, aspen) and farmland. In the north of the region, minor fragments of broad-leaved and dark-coniferous forests have been preserved. On the slopes in small areas there are steppe meadows and meadow steppes. Along the banks of the Belaya and Sim rivers, small fragments of pine forests have been preserved. The flora is mixed, relatively poor.
Security tasks. Key areas with rich biodiversity: valley natural complexes (the Belaya, Sim, Bir, Bystry Tanyp rivers, etc.), restricted forest strips along river banks, numerous sphagnum swamps in karst depressions, old-growth forests, relict island pine forests along the Belaya and Sim. The level of protection is low: 20 small natural monuments and 2 zoological reserves.
Main objects of protection: rare species of plants (salvinia floating, ephedra bispica, rusty schenus, yellow iris, oblique onion, swamp cranberry, water chestnut, blue-blue, etc.).
Species requiring reintroduction or habitat restoration: beautiful feather grass, wood apple tree.
3. Region of deciduous-dark coniferous forests of the Ufa Plateau
General characteristics of the natural complex. A flat hill deeply dissected by river valleys with absolute heights of 450-500m. Karst landforms are widely represented. The climate is moderately warm, well-humidified. Mountain gray forest soils predominate. There are unique frozen soils under green moss forests.
Human influence. The area is heavily developed (long-term logging) and sparsely populated. Factors that threaten biodiversity and deteriorate the ecological situation: logging of the last fragments of indigenous forests (including in restricted areas), air pollution from industrial emissions and acid rain, forest fires, unregulated recreation around the Pavlovsk reservoir, poaching.
Vegetation, flora. In the past, linden-dark coniferous and dark coniferous (spruce, fir) forests predominated. In addition, oak forests were widespread in the western part, and pine and broad-leaved pine forests were widespread in the northern and eastern parts. At present, indigenous forests, disturbed to one degree or another, are preserved mainly only in restricted strips along the Ufa, Yuryuzan, and Ai rivers. The rest of the territory is dominated by secondary birch, aspen and linden forests. Areas of steppe meadows and sphagnum bogs are rare. The flora is mixed boreal-nemoral, enriched with relict Siberian species (Siberian zygadenus, Siberian adonis, bitter bitter, etc.). An endemic species of the Ufa Plateau, the Ural moth, has been described.
etc.................

Although flora, by definition, means full The species composition of plants growing in any territory, in reality, only a part of the species that were identified in this territory always appears in floristic lists. It is a rare researcher who dares to include all plant species in the list, among which in this case both avascular (bryophyte) and vascular plants should be represented. Due to objective disabilities researcher he has to focus primarily on taxa ( systematic groups), in which he considers himself an expert. Other types of restrictions arise when the researcher is particularly interested in any ecological groups, for example, a group of coastal aquatic plants, which, of course, are not limited to the flora of the entire territory of a district or region. A more strict and correct name for limited lists of species found in the study area due to various circumstances - partial floras.

It is not customary to include plant species cultivated by humans in the flora, just as it is not customary to include species that ended up in a given territory as a result of an accidental unintentional introduction. Such species, as a rule, are poorly adapted to unusual local conditions and do not form stable populations. Particular attention is paid to “naturalized” species that, being accidentally introduced ( adventive) or specifically introduced, naturalize, renew themselves in the place where they appeared, regardless of the person. Such species with appropriate notes are included in the flora along with naturally occurring, aboriginal species.

An inventory of flora always involves identifying it. environmental And taxonomic structure.

The ecological structure of the flora is characterized by a spectrum of life forms - the percentage ratio of the number of species representing different life forms. Although quite a lot of classifications of plant life forms have been developed in science, not all of them are used to the same extent to establish ecological structure flora. In this regard, the classification of K. Raunkjær turned out to be the most successful and therefore popular. Based on it, a global ecological spectrum was constructed for the entire flora of vascular plants on the globe. This is usually used as a standard for comparison with the spectra of specific floras. It was found that floras of vascular plants from different regions of the Earth and different biomes naturally differ in the spectrum of life forms. If phanerophyte trees, woody vines and epiphytes predominate in tropical rainforests (hyleas), then in the dry subtropics, with a significant participation of phanerophyte shrubs, grasses still predominate, but in some regions cryptophytes, and in others (in the area of ​​ephemeral deserts) - therophytes. In the floras of temperate and moderately warm humid climates, a sharp predominance of perennial grasses (hemicryptophytes and cryptophytes) is noted.

Characteristics of the ecological structure of the flora can also include the ratio in it relic And progressive elements.

TO relict elements include species for which the conditions of existence in the flora territory seem unfavorable, which is why their populations decrease and their range shrinks. A sign of relict status, even with a more or less stable existence of a species on the territory of the flora, can be considered its narrow local distribution on its territory with a low population size. In contrast to relic progressive elements even with a narrow local distribution occur en masse, and the number of their populations increases. Both relict and progressive components of the flora are represented in it by a small number of species. The balance with environmental conditions in which most species of flora exist does not imply either a sustainable decrease or a sustainable increase in numbers, and the occurrence of such species in the flora remains stable. They can be distinguished into special conservative element of flora. The most abundant species that inhabit various habitats, are stably found in certain phytocenoses and usually play a significant role in their composition can be classified as active species The group of active species corresponds to part of the progressive and part of the conservative species.

The main indicator reflecting taxonomic structure flora can be considered the distribution of its constituent species according to higher taxa and, first of all, families.

The result of a comparison of the richest species, the so-called leading, families allows you to rank these families in descending order of the number of species. The number of families taken for comparison of floras may vary, but, as a rule, biogeographers limit themselves to ten, the composition and relative arrangement of which reveals the specificity of floras of different climatic zones (see Table 1).

Presenters families are distinguished only by the number of flora species included in them, but neither the number of populations or individuals of these species, nor their occurrence, nor their role in the composition of the vegetation cover are taken into account.

The taxonomic structure of floras provides good material for their comparison if we overcome the above-mentioned difficulties with a number of taxa that are problematic for science. For example, the family Asteraceae or Asteraceae, which appears in the characteristics of three of the four climatic zones given in the table, is known for a number of apomictic genera. If, again, we give microspecies the rank of species and, instead of one variable species of dandelion, we recognize the existence of 15–20 species, which is not indisputable, then this will certainly affect the position of the family among the leading ones and promote it upward. It would be possible to use the number of genera in them to identify and rank leading families, but such a technique has not yet become generally accepted.

Table 1. Leading families of flowering plants, arranged in descending order of the number of species, as an indicator of the differences in the taxonomic structure of floras of different climatic zones

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Concept of flora

Flora is the collection of plant species that live in a certain area. We can talk about the flora of a particular region, region, country or any physical-geographical region (for example, the flora of Siberia, the flora of Europe, the flora of the Omsk region, etc.). Often flora also means a list of plants noted in a given area.

Floras of different territories differ significantly in the number of species composing them. This is primarily due to the size of the territory. The larger it is, the greater the number of species, as a rule. By comparing parts of land that are approximately equal in size by the number of plant species growing on them, poor floras and rich floras are identified.

Richest in flora species tropical countries, as you move away from the equatorial region, the number of species quickly decreases. The richest flora is in Southeast Asia with the Sunda Islands archipelago - more than 45 thousand plant species. In second place in terms of richness is the flora of tropical America (the Amazon basin with Brazil) - about 40 thousand species. The flora of the Arctic is one of the poorest, with just over 600 species; the flora of the Sahara Desert is even poorer - about 500 species

The richness of the flora is also determined by the diversity of natural conditions within the territory. The more diverse the environmental conditions, the more opportunities for existence various plants, the richer the flora. Therefore, the floras of mountain systems are, as a rule, richer than lowland floras. Thus, the flora of the Caucasus has more than 6,000 species, but on the vast plain of the central zone of the European part of Russia only about 2,300 species are found.

The richness of the flora may also be due to historical reasons. Older floras, many millions of years old, tend to be particularly rich in species. Plants that became extinct in other areas due to climate change, glaciations, etc. could survive here. Such ancient floras are found, for example, in the Far East and Western Transcaucasia. Young floras, formed relatively recently, are much poorer in species.

Significant differences in systematic composition are observed between floras of different territories. In temperate countries, as a rule, the families of Compositae, legumes, Rosaceae, grasses, sedges and cruciferous plants predominate. In arid areas, various representatives of the goosefoot are very common. Tropical floras are rich in representatives of orchids, euphorbias, madder, legumes, and cereals. In savannas and steppes, cereals come first.

Flora elements

Arctic - a group of species whose habitats are in the Far North, in the continental tundra zone and on the Arctic islands. It breaks up into a number of smaller elements, for example, Western Arctic and Eastern Arctic. On the other hand, some arctic species have parts of their ranges (disjunctions) in the Caucasus, Altai, etc., so we can talk about the elemental arctic-caucasian, arctic-alpine, etc. Location of grains.

Northern (or boreal) - a group of species with habitats located mainly within the northern parts of the forest region, namely in the area of ​​\u200b\u200bconiferous forests. Here, too, there are further divisions: Euroboreal - only in the European part, Sibboreal in Siberia, etc.

Central European - a group of species with habitats in Central Europe, extending the eastern segments of their ranges into the western part of the Union, in some cases even extending beyond the Urals.

Basically, this group, more thermophilic compared to the previous one, is distributed in the area of ​​deciduous forests.

Examples: common oak (reaches the Urals), Norway maple (as well as field and Tatarian maples), ash, hornbeam, beech, winter oak (Quercus petraea), herbaceous species characteristic of broad-leaved forests, such as hoofweed, Peter's cross (Lathraea squamaria ), lungwort (Pulmonaria officinalis, etc. Range of lungwort.

Atlantic - found in the western regions of the European part of the USSR. This element is most strongly represented in the Atlantic coastal parts of Europe. Some species move more eastward. Among the plants growing on our territory, we can mention lobelia (Lobelia Dortmanna), waxweed (Myrica Gale).

Pontic - a group of species mainly of the southern Russian steppes, but also found in the Romanian and Hungarian steppes (if the species are found mainly in the Hungarian steppes, then this is a Pannonian element). This includes numerous species of our steppe spaces: adonis (Adonis vernalis), chickweed (Stachys recta), purple mullein (Verbascum phoeniceum), yellow scabiosa (Scabiosa ochroleuca), steppe cherry (Cerasus fruticosa), broom (Cytisus ruthenicus), etc. The Pannonian element in We are very poorly represented. Habitat of the adonis.

Sarmatian - unites species that occupy the territory between the southern steppes and coniferous forests in the north, without going far to the west, beyond the western borders of the Union. These species are less heat-loving compared to the Pontic ones. A few examples: pea (Vicia pisiformis), hill violet (Viola collina), sandy astragalus (Astragalus arenarius) (Recently, some Russian authors have interpreted the Sarmatian element in a different sense: under the name of this element they combine species that cover mainly Northern Kazakhstan with their ranges (and partly Southern Siberia); these are generally steppe species. It is better, in order to avoid confusion, to talk here about the North Kazakhstan element).

Mediterranean - a group of species distributed in dry areas surrounding the Mediterranean Sea, and in the east growing on the coasts of the Black Sea - in the Crimea and the Caucasus (also in the Caspian regions). Trees and shrubs with evergreen leathery leaves and dry-loving herbs. Examples: strawberry tree (Arbutus andrachne), boxwood (Buxus sempervirens), sumac (Rhus coriaria), wild jasmine (Jasminum fruticans), etc. Some authors also include Western and Central Asian elements in the Mediterranean element. Boxwood habitat.

Near Asian. This includes species that have a habitat in the countries of Western Asia - from the borders of Iran in the east to the shores of the Mediterranean Sea. These are mainly plants of dry mountainous countries. It breaks down into a number of elements of a narrower meaning, of which we note the Iranian one, which generally coincides with the Iranian Plateau and extends into our borders in Transcaucasia. 9. Central Asian - confined to Central Asia, to its large mountain ranges (Tien Shan, Pamir-Alai, Tarbagatai, Altai). It is very complex and breaks down into a number of smaller elements.

Turanian - unites a group of species whose habitats are mainly associated with the deserts of the Turanian lowland of Central Asia. Element of desert character. In basic terms, this is an Aralocaspian element of some authors, which, however, is usually understood somewhat more broadly. A typically Turanian element is the group of Central Asian desert wormwoods (Artemisia). Range of white wormwood.

Manchurian is a group of species that has its main area of ​​distribution in Manchuria and extends into the southern parts of the Far Eastern region. A number of trees and shrubs of the broad-leaved type: Manchurian walnut (Juglans manshurica, Fig. 108), Manchurian aralia (Aralia manshurica), velvet tree (Phellodendron amurense, variegated hazel (Corylus heterophylla), etc.

Elements of the flora of the Caucasus. Especially for the Caucasus, you can indicate some more geographical elements, spatially more limited. Caucasian - consists of species connected by their habitats with the Greater Caucasus; this includes Caucasian endemics (forest and alpine). Colchis is a group of species that have their range in the Colchis province of the Caucasus, i.e. in Western Transcaucasia (Adjara, Abkhazia and the more northern coast). Forest, limestone, mountain-meadow species. The majority are elements ancient in their genesis (tertiary): pontic oak (Quercus pontica), rhododendron (Rhododendron Smirnowii), birch (Betula Medwedewii), etc. Hyrcanian - species occupying the extreme southeast of the Caucasus, but the bulk of species are concentrated abroad - in Northern Iran. Ancient tertiary elements (mainly forest species): Parrotia persica, honey locust (Gleditschia caspia), silk acacia (Albizzia julibrissin), genus Danae, etc.

floristic saturation phytogenic swamp

The concept of floristic richness and floristic saturation

Floristic composition is the complete set of plant species found within a particular plant community.

Floristic composition is the most important constitutional feature, largely determining the structure and functions of the community. This is a very informative sign that speaks about the environmental conditions in which the community is located, its history, the degree and nature of its disturbance, etc.

The floristic composition is characterized by a number of indicators.

The first is species richness, that is total species characteristic of the phytocenosis. This indicator can vary from 1 (monodominant single-species communities) to 1000 or more species (some tropical forests). According to the witty remark of R. Margalef (Margalef, 1994), species richness can in any case be placed between two extreme situations: the “Noah’s Ark” model - there are a lot of species, but each is represented by only one pair of individuals, and the “Petri dish” - a microbiological culture , in which a huge number of individuals of one species are represented. Species richness is the simplest measure of alpha diversity, that is, biotic diversity at the phytocenosis level.

With all the interest in the indicator of the degree of species richness, it is obvious that its use in comparative analytical constructions is in many cases incorrect. So, for example, a small swamp and a section of tropical forest are incomparable in terms of species richness. Therefore, in geobotany, the indicator of species saturation is much more often used - the number of species per unit area. But here it should be noted that in order to determine the species richness of a phytocenosis, it is necessary in any case to know its species richness.

If species richness is identified using square or round areas of increasing size inscribed within each other, then, as a rule, as the area of ​​the recording unit increases, the number of species identified in the phytocenosis will increase. If you construct a curve from the obtained values, it will fairly well reflect the dependence of the increase in the number of species on the size of the counting area. As a rule, such a curve will initially rise sharply, and then gradually reach a plateau. The beginning of the transition to the plateau will show that on an area of ​​this size the overwhelming number of species in the phytocenosis have already been identified. As a rule, the richer the phytocenosis is in species, the smaller the size of the area at which the curve reaches a plateau.

In order to characterize the floristic composition of the phytocenosis as fully as possible, all plants are first recorded, standing at one point on the border of the described area. After all the plants have been marked, including the most inconspicuous ones visible from the observation point, they slowly move along the border, recording new plants that have not yet been included in the list. Walking around the entire area. make its intersection diagonally, continuing to fit in the plants. This method of recording ensures the completeness of the list and saves the described area from trampling by the researcher.

With a single count of species composition, it is usually impossible to obtain full list species characterizing the phytocenosis. Some species have a short growing season, dormant for the rest of the year as seeds or underground organs; other species begin their development late and are not included in the lists compiled during the spring description of the phytocenosis. Therefore, to obtain more complete information about the floristic composition of the community, it is necessary to compile lists of plants two or three times during the growing season.

Characteristics of the flora of the world

A section of the earth's surface with its inherent relief, ground layer of the atmosphere, surface and underground waters, soils, communities of flora and fauna, naturally interconnected, is called a natural-territorial complex (NTC). This same concept is also called “geosystem”. An ecosystem, which is the basic concept of environmental science, is a collection of living organisms and their environment in interaction based on metabolism and directed energy flows: These concepts are very close in content: in all three concepts we are talking about a certain area of ​​the earth's surface. Geosystems, or PTC, mean areas of the earth's surface at various levels that are in regular relationships, from the smallest - facies - to the global - geographical shell. Ecosystems mean spatial units of various sizes inhabited by organisms characterized by species composition, abundance and biomass, distribution patterns and seasonal dynamics. The highest-ranking ecosystem is the biosphere. The biosphere and the geographical envelope are almost identical concepts. In ecology and geography, not only global units, such as the biosphere and the geographical envelope, coincide, but also others of a lower rank: as concepts that are close in meaning, but different in form. For example, “facies” in landscape science and “zone” in physical geography are very close in meaning to both biological and ecological terms - “biocenosis” and “biome”.

In ecology, biological organisms, their relationships with the environment, species composition, biomass and energy exchange are placed in the foreground, since living organisms are distinguished by bio-geochemical activity. Especially green plants, which, as a result of the process of photosynthesis, continuously exchanging substances and energy with non-living components of nature, create primary organic products. In nature, only green plants convert solar energy into biochemical energy and accumulate it. Due to such accumulated energy of green plants, life exists and is preserved on Earth. Animals feed on organic substances synthesized by plants, thanks to which they continue their species. Living organisms that provide continuous metabolism and energy flows form the basis of the ecosystem. The most important component in it is the plant environment, which influences the soil, fauna and microorganisms. The state of vegetation determines the nature of biogeocenoses, their morphological and functional structure.
In the decision environmental problems conservation plays a big role in the process economic activity human natural state of green plants, land area and species diversity. A reduction in the annual production of green plants negatively affects the biochemical cycle of substances and energy flows, and the preservation of ecological balance in the ecosystem. And negative results cannot but affect a person’s life. The ecological situation among animal organisms is directly related to ecological condition vegetation.

For humanity vegetable world - essential component habitats, the main source of food, medicinal and technical raw materials, and building materials. Vegetation is the main basis for livestock production. Cultivated plants are also grown to improve the human environment, as well as to increase soil fertility, protect them from water and wind erosion, to consolidate loose sand, etc.

However, vegetation as one of the components of the natural-territorial complex is quite vulnerable and has low resistance to external influences. In the hierarchical system of a natural-territorial complex, vegetation is dependent on a number of components. Of the PTC components, the most stable is the lithological link, i.e. geological structure and relief. Air mass also one of the stable components of the PTC. After them comes the water component, then the soil, and then just the vegetation. Changing any of the above components will result in disruption of the herbal component. If the relief is disturbed, the soil is washed away, the water regime is changed, then there can be no question of preserving natural vegetation. But, if other components of nature have not undergone changes, then it is possible to preserve and restore the plant environment.

The fauna is also an important part of the biosphere. Animals are the most vulnerable component of the PTC - the main consumer of primary organic products created by plants that provide the cycle chemical elements in the biosphere.

Animals play a significant role in soil fertility and rock weathering. Animal organisms in the soil, such as earthworms, various beetles, spiders, microorganisms, and digging rodents, constantly mix the soil, loosening it, increasing the pores and voids in it, promoting the penetration of air into the soil and, together with the remains of dead plants and animals, increasing its fertility . Small insects provide plant pollination, thereby creating the possibility of quantitative reproduction. By carrying the seeds of some plants from place to place, they help them spread. Animals improve rangeland to a certain extent, and only an excessive number of them within a limited area can lead to deterioration of the soil cover.

Animals play an important role in people's lives. They provide us with food and serve as a raw material base for industry. Wild animals are a source of genetic fund for livestock breeding. At the present stage, people are trying to domesticate different types of wild animals, in order, for example, to use their valuable fur.
Some species of animals cause serious damage to the farm, and people try to reduce such losses.

The fauna, together with the plant world, is the most important component of the ecosystem, a factor that determines its current state. Ecological situations on the ground are determined by the state in which people, animals and plants are.).
The fauna, as one of the components of the natural-territorial complex, is the most vulnerable, especially susceptible to external influences, including those resulting from human economic activity, and has the least stability. This component is dependent on all other PTC components. In the hierarchical series of the geosystem, it occupies the last step, therefore the influence of human economic activity is primarily reflected on it, leading to a sharp increase in the number of some species, a decrease in others, or the complete disappearance of others. The fauna is the most affected of all the components of the PTC from human economic activities.

Floristic division of the Earth

An attempt at floristic zoning of the globe's landmass was made back in the first half of the 19th century. Floristic zoning can be based on various principles. In particular, it is possible to identify individual areas depending on the richness of species, features of systematic composition, and the presence or absence of certain elements of the flora.

However, most often the land area of ​​the globe is divided into a series of mutually subordinate regions, or phytochorions (from the Greek phyton - plant and khoros - space), identified on the basis of similarities and differences in the systematic composition of their floras. As new data is accumulated, it is repeatedly updated. A significant contribution to the zoning of the Earth according to the composition of floras was made by the Russian botanist A.L. Takhtadzhyan in his book “Floristic Regions of the Earth” (1978). Of essential importance in determining the boundaries of phytochorions is the analysis of habitats and the identification of geographical and genetic elements of a given flora.

Where the composition of the main elements of the flora changes, one flora is replaced by another. In works on floristic zoning, the distribution of endemics in floras is especially important.

Endemics are species (of plants) that are not found anywhere except in a given territory. Endemism is a broader concept, since endemic species can form endemic genera and even endemic families over larger areas. The degree of endemism varies greatly among different areas. The floras of isolated oceanic islands are highly endemic. Thus, for the flora of the Hawaiian Islands, 82% of endemics are indicated, for the flora of the Galapagos Islands - more than 50, in the native part of the flora of New Zealand - 82%. Of the continental floras, the most isolated is the flora of Australia - a continent that has long been isolated from other significant land areas.

Here, out of 12 thousand species, more than 9 thousand are endemic. But the number of endemic families here is still less than in East and Southeast Asia. Among endemics, botanists try to distinguish between paleoendemics and neoendemics. Paleoendemics have ancient origin. These are, as a rule, systematically isolated taxa. The number of paleoendemics largely determines the originality and antiquity of the flora. Neoendemics most often include species, less often genera, that arose relatively recently and have not yet had time to spread widely. There are especially many neoendemics in mountain ranges. A large number of neoendemics indicates active speciation processes and the relative youth of the main core of the flora. The centers of modern diversity of certain taxa are primarily associated with the abundance of neoendemics.

Floristic kingdoms

Floristic kingdoms (regions) of the globe, the largest associations of floras related by origin, historically formed on certain areas of the Earth’s surface. Isolation of F. c. is substantiated primarily by paleogeographical factors (starting mostly from the Cretaceous period), as well as modern soil and climatic factors. In every F. c. have their own complexes of endemic families and genera of plants, the origin and distribution of which over a long period of time geological history flowed within its boundaries. F. c. are subdivided into subordinate floristic units of lower rank (floristic regions, provinces, districts, districts, etc.). Although in the division of the earth's surface into F. c. (or regions) by different authors there are discrepancies, in its fundamental basis it is uniform (see Floristic zoning).

The vast Holarctic floristic kingdom (or Holarctic region) occupies the entire extratropical space of the North. hemisphere, in the south to the Cape Verde Islands, north. parts of the Sahara and Arabia, the coast of the Persian Gulf, southern. slopes of the Hindu Kush and Himalayas, extreme southern China, in the North. America - to the north. parts of the Mexican Highlands and the shores of the Gulf of Mexico.

Historically, the floras of the Holarctic are associated with the ancient Paleogene-Neogene Arcto-Tertiary floristic complex, its derivatives, and the Amer. Madro-Tertiary floras. Connections with tropical floras proper have long been limited to the vast Tethys basin, the isolating role of which countered the similarity of the climatic conditions of the southern Holarctic with the tropical ones proper. Flora of Holarctic F. c. is highly differentiated, which forces it to be divided into a number of floristic regions: Arctic - has poor floras with a predominance of families such as grasses, sedges, cruciferous plants, carnation plants, asteraceae, etc.; Boreal - characterized by the dominance of coniferous trees; according to the number of species, cereals, sedges, and asteraceae are distinguished; Central European is characterized by the predominance of deciduous tree species (temperate forests), an abundance of grasses, Asteraceae, Rosaceae and other groups common to the Holarctic; Mediterranean - richly represented by Asteraceae, Papilaceae, Poaceae, Cruciferae, Lamiaceae, Dianthus, Apiaceae (the flora is highly differentiated in space, progressive endemism is clearly expressed); Central Asian - relatively poor flora, similar to the Mediterranean, Boreal and East Asian; East Asian has retained many features of Arctic-Paleogene-Neogene species in combination with the development of progressive endemism; Californian (Sonorian) and Appalachian - the basis of the flora is made up of relicts of the Paleogene-Neogene and Madro-Paleogene-Neogene complexes with elements of progressive endemism.

The paleotropical floristic kingdom (or Paleotropical region) occupies the space south of the Holarctic floristic kingdom (in the Eastern Hemisphere) to the subtropics of South Africa, along with the islands of the Indian and Pacific oceans. The flora is rich and highly differentiated. The leading position is occupied by pantropical families, which are characterized by division into the territories of the Old and New Worlds (for example, palm trees and orchids); Rubiaceae, Euphorbiaceae, palms, orchids, melastomaceae, aroids, mulberries, laurelaceae, and a number of groups of tubiferous plants are widespread. Cosmopolitan families and species are represented by cereals, legumes, Asteraceae, etc. There are few endemic families - dipterocarpaceae, pandanaceae, and some others. The species composition of floras is rich, especially in areas where forest vegetation predominates. The richness and differentiation of floras make it possible to distinguish the following regions in the paleotropical kingdom: Sahara-Sindian, Sudano-Zambezian, Guinea-Congo, Kalahari, Cape, Madagascar, Hindustan, Indochina, Malay, Papuan, Hawaiian, Polynesian.

The Neotropical floristic kingdom (or Neotropical region) occupies the space of the New World from the South. California and the Bahamas to 41° S. w. The flora is characterized by the massive presence of cosmopolitan (orchids, asteraceae, legumes, cereals, etc.) and pantropical (palm, myrtle, euphorbia, madder, etc.) families. The families of cacti, bromeliads, etc. are endemic. Changes in the richness of floras mainly depend on climatic conditions (the humid and hot forest areas of the equatorial zone, rich in species composition, change when moving to subtropical latitudes and when ascending to the mountains). The following regions are distinguished: Caribbean, Orinoco, Amazonian, Brazilian, Laplata, Andean.

The southern floristic kingdom occupies the mainland of Australia and the island. Tasmania, New Zealand with adjacent islands, the extreme south of South. America, subantarctic islands and Antarctica. The most distinctive flora of Australia is the myrtaceae (in particular, eucalyptus), proteaceae, mimosa, epacridaceae, humeniaceae, restiaceae, casuarinaceae, etc. There are the Australian (a number of botanists consider it as a floristic kingdom), New Zealand, New Caledonian and Magellanic-Antarctic regions.

Phytogenic factors, their classification and characteristics

In the domestic literature, the most common classification of forms of relationships between plants according to V.N. Sukachev (Table .

Table The main forms of relationships between plants (according to V. N. Sukachev, N. V. Dylis et al., 1964).

Direct (contact) interactions between plants

An example of mechanical interaction is damage to spruce and pine in mixed forests from the whipping action of birch. Swaying from the wind, thin birch branches injure spruce needles and knock down light young needles. This is very noticeable in winter, when the branches of the birch are leafless.

Mutual pressure and cohesion of trunks often has a negative effect on plants. However, such contacts are more often found in the underground sphere, where large masses of roots are closely intertwined in small volumes of soil. The types of contacts can be different - from simple adhesion to strong fusion. Thus, the growth of vines is destructive in the life of many tropical forest trees, often leading to branches breaking off under their weight and trunks drying out as a result of the compressive action of climbing stems or roots. It is no coincidence that some vines are called “stranglers” (Fig. 1).

Rice. 1 Liana plants: 1 - strangler ficus; 2 - dodder; 3 - climbing honeysuckle (according to N.M. Chernova et al., 1995)

According to scientists, about 10% of all plant species lead an epiphytic lifestyle. Tropical forests are richest in epiphytes. These include many species of bromeliads and orchids (Fig. 2).

Rice. 2 Epiphytic orchid with aerial roots: A - general view; B - cross section of an aerial root with an outer layer of absorbent tissue (1) (according to V.L. Komarov, 1949)

The ecological meaning of epiphytism is a unique adaptation to the light regime in dense tropical forests: the ability to get to the light in the upper tiers of the forest without large expenditures of substances for growth. The very origin of the epiphytic lifestyle is associated with the struggle of plants for light. The evolution of many epiphytes has gone so far that they have already lost the ability to grow outside the plant substrate, i.e. they are obligate epiphytes. At the same time, there are species that can grow in soil in greenhouse conditions.

A typical example of close symbiosis, or mutualism, between plants is the cohabitation of an algae and a fungus, which form a special integral lichen organism (Fig. 3).

Rice. 3. Cladonia lichen (according to N.M. Chernova et al., 1995)

Another example of symbiosis is the cohabitation of higher plants with bacteria, the so-called bacteriotrophy. Symbiosis with nitrogen-fixing nodule bacteria is widespread among legumes (93% of the studied species) and mimosa (87%). Thus, bacteria from the genus Rhizobium, living in nodules on the roots of leguminous plants, are provided with food (sugars) and habitat, and the plants receive from them an accessible form of nitrogen in return (Fig. 5).

Rice. 5 Nodules on the roots of leguminous plants: A - red clover; B beans; B - soybeans; G - lupine (according to A.P. Shennikov, 1950).

There is a symbiosis of the mycelium of the fungus with the root of a higher plant, or mycorrhiza formation. Such plants are called mycotrophic, or mycotrophs. By settling on plant roots, fungal hyphae provide higher plant colossal suction capacity. The surface of contact between root cells and hyphae in ectotrophic mycorrhiza is 10-14 times larger than the surface of contact with the soil of bare root cells, while the suction surface of the root due to root hairs increases the root surface only 2-5 times. Of the 3425 species of vascular plants studied in our country, mycorrhiza was found in 79%.

An example of the symbiosis of fungi and insects is the symbiosis of the fungus Septobasidium with the insect worm from Coccidae, which gives a new symbiotic formation - varnishes, which, as a single organism, was introduced into culture by humans.

A separate group of plants with heterotrophic nutrition consists of saprophytes - species that use organic substances of dead organisms as a source of carbon. In the biological cycle, this important link that carries out the decomposition of organic residues and the transformation of complex compounds into simpler ones is represented mostly by fungi, actinomycetes, and bacteria. They are found among flowering plants in representatives of the families of wintergreens, orchids, etc. Examples of flowering plants that have completely lost chlorophyll and switched to feeding on ready-made organic substances are saprophytes of coniferous forests - the common moth (Monotropahypopitis), the leafless mullet (Epipogonaphylluon). Saprophytes are rare among mosses and ferns.

The fusion of roots of closely growing trees (of the same species or related species) also refers to direct physiological contacts between plants. The phenomenon is not so rare in nature. In dense stands of Piceaflies spruce, the roots of about 30% of all trees grow together. It has been established that between fused trees there is an exchange through the roots in the form of transfer of nutrients and water. Depending on the degree of difference or similarity in the needs of the fused partners, relationships of a competitive nature in the form of the interception of substances by a more developed and stronger tree, as well as symbiotic ones, cannot be excluded between them.

The form of connections in the form of predation has a certain significance. Predation is widespread not only between animals, but also between plants and animals. Yes, a row carnivorous plants(sundew, nepenthes) are classified as predators (Fig. 6).

Rice. 6 Predatory plant sundew (according to E. A. Kriksunov et al., 1995)

Indirect transbiotic relationships between plants (through animals and microorganisms). The important ecological role of animals in plant life is their participation in the processes of pollination, distribution of seeds and fruits. Pollination of plants by insects, called entomophily, contributed to the development of a number of adaptations in both plants and insects. Let us name here such interesting adaptations of entomophilous flowers as patterns that form “path threads” to nectaries and stamens, often visible only in ultraviolet rays accessible to the vision of insects; difference in flower color before and after pollination; synchronization of the daily rhythms of opening of the corolla and stamens, ensuring the unmistakable hit of the finger on the body of the insect, and from it on the stigma of another flower, etc. (Fig. 7).

Rice. 7 Insect on a flower (according to N.M. Chernova et al., 1995)

Varied and complex structure of flowers ( different shape petals, their symmetrical or asymmetrical arrangement, the presence of certain inflorescences), called heterostyly, are all adaptations to the body structure and behavior of strictly specific insects. For example, flowers of wild carrot (Daucuscarota), caraway (Carumcarvi), pollinated by ants, flowers of the Asarumeuropaeum, pollinated by ants and, accordingly, do not rise from under the forest floor.

Birds also take part in pollinating plants. Pollination of plants by birds, or ornithophily, is widespread in tropical and subtropical regions of the southern hemisphere. There are about 2,000 species of birds known here that pollinate flowers while searching for nectar or catching insects hiding in their corollas. Among them, the most famous pollinators are sunbirds (Africa, Australia, South Asia) and hummingbirds (South America). The flowers of ornithophilous plants are large and brightly colored. The predominant color is bright red, most attractive to hummingbirds and other birds. Some ornithophilous flowers have special protective devices that prevent nectar from spilling out when the flower moves.

Less common is plant pollination by mammals, or zoogamy. For the most part, zoogamy is observed in Australia, in the forests of Africa and South America. For example, Australian shrubs of the genus Driandra are pollinated by kangaroos, who readily drink their abundant nectar, moving from flower to flower.

The distribution of seeds, fruits, and spores of plants with the help of animals is called zoochory. Among plants whose seeds and fruits are dispersed by animals, in turn, a distinction is made between epizoochorous, endozoochorous and synzoochorous. Epizoochorous plants, mostly in open habitats, have seeds and fruits with all sorts of devices for fastening and holding on the surface of the animal’s body (outgrowths, hooks, hitches, etc.), for example, large and cobwebby burdock, common Velcro, etc.

In the shrub layer of forests, where many birds live, endozoochorous plant species predominate. Their fruits are edible or attractive to birds due to their bright colors or juicy pericarp. It should be noted that the seeds of many endozoochorous plants increase germination, and sometimes the ability to germinate, only after passing through the food tract of an animal - many Araliaceae, Malussieversu apple tree, etc.

Animals do not eat edible fruits and seeds of oak and Siberian pine immediately, but take them away and put them in stock. A significant part of them is lost and, under favorable conditions, gives rise to new plants. This distribution of seeds and fruits is called synzoochory.

In indirect transbiotic relationships, microorganisms often act among plants. The rhizosphere of the roots of many trees, for example, oak, greatly changes soil environment, especially its composition, acidity, and thereby creates favorable conditions for the settlement of various microorganisms, primarily bacteria, such as Azotobacterchroocoteum, Tricholomelegnorum, Pseudomonassp. These bacteria, having settled here, feed on secretions of oak roots and organic debris created by the hyphae of mycorrhizal fungi. Bacteria, living next to the roots of the oak tree, serve as a kind of “defense line” against the penetration of pathogenic fungi into the roots. This biological barrier is created by antibiotics secreted by bacteria. The settlement of bacteria in the oak rhizosphere immediately has a positive effect on the condition of plants, especially young ones.

Indirect transabiotic relationships between plants (environment-forming influences, competition, allelopathy). Changing the environment by plants is the most universal and widespread type of relationship between plants when they coexist. When one or another species or group of plant species in the C, as a result of its life activity, greatly changes the basic ecological factors in quantitative and qualitative terms in such a way that other species of the community have to live in conditions that differ significantly from the zonal complex of factors of the physical environment, then this indicates environment-forming role, environment-forming influence of the first type in relation to the others. One of them is mutual influence through changes in microclimate factors (for example, weakening of solar radiation within the vegetation cover, depletion of it in photosynthetically active rays, changes in the seasonal rhythm of illumination, etc.). Some plants influence others through changes in air temperature, humidity, wind speed, carbon dioxide content, etc.

Another way of interaction of plants in communities is through the ground layer of dead plant debris, called rags, herbaceous decay or “steppe felt” in meadows and steppes, and litter in the forest. This layer (sometimes several centimeters thick) makes it difficult for seeds and spores to penetrate the soil. Seeds germinating in (or on) a layer of rags often die from drying out before the roots of the seedlings reach the soil. For seeds that fall into the soil and germinate, soil residues can be a serious mechanical obstacle to the seedlings’ path to light. Relationships between plants are also possible through the decay products of plant residues contained in the litter, which inhibit or, on the contrary, stimulate plant growth. Thus, fresh litter of spruce or beech contains substances that inhibit the germination of spruce and pine, and in places with scanty precipitation and poor washing of the litter they can inhibit the natural regeneration of tree species. Water extracts from forest litter also have a negative effect on the growth of many steppe grasses.

A significant way of mutual influence of plants is interaction through chemical secretions. Plants are isolated in environment(air, water, soil) various chemical substances in the process of guttation, nectar secretion, essential oils, resins, etc.; when mineral salts are washed away by rainwater, leaves, for example, of trees, lose potassium, sodium, magnesium and other ions; during metabolism (root secretions) gaseous substances released by above-ground organs - unsaturated hydrocarbons, ethylene, hydrogen, etc.; when the integrity of tissues and organs is violated, plants release volatile substances, so-called phytoncides, and substances from dead parts of plants (Fig. 8).

The released compounds are necessary for plants, but with the development of a large plant body surface, their loss is as inevitable as transpiration.

Chemical secretions from plants can serve as one of the ways of interaction between plants in a community, having either a toxic or stimulating effect on organisms.

Rice. 8 The influence of one plant on another (according to A. M. Grodzinsky, 1965): 1 - miasmins; 2 - phytoncidal substances; 3 - phytogenic substances; 4 - active intravital secretions; 5 - passive intravital discharge; 6 - post-mortem discharge; 7 - processing by heterotrophic organisms

Such chemical interactions are called allelopathy. An example is the secretion of beet fruits, which inhibits the germination of cockle seeds (Agrostemmagithago). Chickpeas (Cicerarietinum) have a suppressive effect on potatoes, corn, sunflowers, tomatoes and other crops, beans - on the growth of spring wheat; root secretions of wheatgrass (Agropyronrepens) and brome (Bromusinermis) - on other herbaceous plants and even trees growing near them. As an extreme form of allelopathy or the impossibility of the existence of one or another species in the presence of another as a result of environmental intoxication, it is called amensalism. Amensalism corresponds to direct competition, antibiosis and antagonism. Thus, due to the release of toxic substances by its roots, hawkweed (Hieraciumpilosella) from the Asteraceae family displaces other annual plants and often forms pure thickets over fairly large areas. Many fungi and bacteria synthesize antibiotics that inhibit the growth of other bacteria. Amensalism is widespread in the aquatic environment.

In different plant species, the degree of impact on the environment and thus on the life of the inhabitants is not the same in accordance with the characteristics of their morphology, biology, seasonal development, etc. Plants that most actively and deeply transform the environment and determine the conditions of existence for other co-inhabitants are called edificators. There are strong and weak edificators. Strong edificators include spruce (strong shading, depletion of soil nutrients, etc.), sphagnum mosses (moisture retention and creation of excess moisture, increased acidity, special temperature regime etc.). Weak edificators are deciduous trees with an open crown (birch, ash), and herbaceous forest plants.

Competition is identified as a special form of transbiotic relationships between plants. These are those mutual or unilateral negative influences that arise based on the use of energy and food resources of the habitat. Competition for soil moisture (especially pronounced in areas with insufficient moisture) and competition for soil nutrients, more noticeable in poor soils, have a strong influence on plant life. An example of competition is the relationship between meadow foxtail (Alopecurus pratensis) and fescue (Festucasulcata). Fescue can grow in moist soil, but does not grow in the foxtail meadow community due to suppression by the shade-tolerant and fast-growing foxtail. In the formation of a fescue or foxtail phytocenosis, the decisive factor is not soil moisture, but the competitive relationship between fescue and foxtail. In drier habitats, fescue drowns out foxtail, but in moist meadows, foxtail emerges victorious.

Interspecific competition manifests itself in plants in the same way as intraspecific competition (morphological changes, decreased fertility, abundance, etc.). The dominant species gradually displaces or greatly reduces its viability.

The most severe competition, often with unforeseen consequences, occurs when new plant species are introduced into communities without taking into account already established relationships.

Swamp concept

A swamp is an area of ​​the earth's surface characterized by abundant stagnant or weakly flowing moisture in the upper horizons of soils, on which specific swamp vegetation grows, adapted to conditions of abundant moisture and lack of oxygen in the soil.

If the thickness of the deposited peat is such that the roots of the bulk of plants reach the underlying mineral soil, then in this case the excessively moist land areas are classified as wetlands or swamps in the initial stage of their development.

The task of hydrology includes the study of the hydrological (and especially water) regime of swamps both in the initial stages of their formation (wetlands and waterlogged reservoirs) and in subsequent phases of development (marsh massifs).

The division of wetlands into wetlands and swamps is largely a reflection of differences in vegetation composition. Purely swamp forms of plant groups do not appear simultaneously with the beginning of the swamping process. As long as the thickness of the peat is small and the root systems of the main plant species are not detached from the mineral soil underlying the peat, the vegetation cover includes plants characteristic of both swamp and non-marsh habitats.

Due to the fact that the condition that determines the existence of certain plant associations in excessively wet areas is primarily the water regime, the indicated difference between wetlands and swamps in the subsequent stage of their development also has hydrological significance. In addition to defining a bog as a hydrological object, there are definitions in which a bog is considered as an object for peat extraction, that is, from the point of view of the presence or absence of fuel reserves in it.

Ways of formation of swamps

There are three main stages in the development of swamps.

First stage.

Lakes are natural bodies of water in depressions of land (basins), filled within the lake bowl (lake bed) with heterogeneous water masses and not having a one-way slope. Based on their origin, lake basins are divided into tectonic, glacial, river (oxbow lakes), coastal (lagoons, estuaries), sinkholes (karst, thermokarst), volcanic (in the craters of extinct volcanoes), dammed lakes, artificial (reservoirs, ponds). According to their water balance, lakes are divided into drainage and drainageless; By chemical composition water - fresh and mineral.

This is not unimportant, since a huge amount of mineral substances are delivered to the lakes by ground or above-ground waters, and organic matter (plus mineral substances) is brought with the waters of coastal washout and springs (ground type of nutrition).

Water mineralization, saturation of water with inorganic (mineral) substances found in the form of both ions and colloids.

During the life of plants and animals, a substance called sapropel, organic silt, consisting mainly of organic substances and the remains of aquatic organisms, is formed at the bottom of lakes. Sapropel is used as fertilizer. Plants along the shore of the reservoir (trees, shrubs) correspond to the types found in the area. But aquatic and wetland plants (reeds, reeds, water lilies, pondweed) are already beginning to do their job.

At this stage, representatives of fish, fish-like organisms, mollusks, etc. are still visible. You can also see plankton, which reproduce especially abundantly during the period of spring mixing of water, when its temperature promotes the reproduction process and the amount of oxygen reaches its highest level (oxygen dissolved in water).

Dokturovsky V.S. wrote: “From the edges of the shores of the lake, wetland vegetation gradually moves towards the middle of the reservoirs... leaving in their center only a small lake, which, instead of shores with mineral soil, is surrounded by peat...”

Second stage of development.

A layer of lowland peat is formed here (it unites 24 species), and marsh plants predominate. The boundaries of peat and sapropel coincide. Atmospheric recharge maintains weak washout from the banks and promotes swamping by replenishing the upper layer with water. Evaporation processes are negligible compared to the process of water entering from the soil and atmosphere.

The supply of water from the ground may be partially disrupted, but more often a constant supply prevails. This process contributes to the growth of the swamp, which gradually increases its volume. But the volume is due to the growth of peat, which in turn is the main reason for the increase in the volume of the swamp.

Peat formation occurs within the peat layer. This layer is located at the top (0.2 -0.7 m) of the peat deposit.

When water stands high, anaerobic conditions arise and decomposition processes slow down.

Third stage.

At this stage of development, the type of swamp is fully formed, that is, we can already determine what kind of swamp it is: lowland, transitional or upland. Consider, for example, a low-lying swamp. So, before us is a formed lowland swamp. The layer of lowland peat accumulated during the growth of the bog landscape is quite high. The vegetation cover is widely represented by the marsh plants described above. Representative trees - spruce and birch - spread across the surface of the swamp. The sapropel layer is significantly increased. The boundary between peat and sapropel with interpenetration can be traced. Atmospheric nutrition brings oxygen and contributes to swamping of areas. The supply of water from the ground in some cases supports, and in others contributes to an increase in the volume of the swamp. Evaporation processes are slowed down. Continuous vegetation cover retains moisture. Growth processes prevail over decomposition processes. And in this sense, swamps are one of the first places in terms of productivity (its relation to decomposition processes).

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FEATURES OF FLORA OF BURNS OF THE DESERT-STEPPE ZONE OF UKRAINE

Mounds are ancient burial places covered on top by a dome-shaped earthen embankment. The burial mound culture was very widespread in the past. In Ukraine, the construction of mounds lasted over 4 thousand years (from the end of the 3rd millennium BC to the 13th century AD), over several eras: the Chalcolithic, Bronze Age, Early Iron Age, Antiquity and the Middle Ages. This type of burial is characteristic of many peoples, and among the peoples who inhabited the Black Sea region at different times - for the Cimmerians, Scythians, Sarmatians, Huns, Bulgarians, Hungarians, Pechenegs, Turks, Cumans, Nogais, etc. In general, more than 50 thousand burial mounds are known in Ukraine.
Before the massive plowing of the south of Ukraine, the mounds were surrounded by virgin steppe vegetation for centuries, which contributed to the formation of steppe vegetation cover on them that was close to natural. During the development of the steppes, on most mounds (especially not large ones), the steppe vegetation was destroyed (mainly by plowing), or the mounds themselves were completely destroyed. However, some of the mounds, especially large ones, have never been plowed up and the steppe vegetation cover has been preserved on them, which differs sharply from the segetal vegetation that surrounds them, in most cases.
As part of the study of the flora of mounds in the steppe and forest-steppe of Ukraine, in 2004-2006 we examined the features of the flora of mounds located in the desert steppe zone, in the Golopristansky and Skadovsky districts of the Kherson region of Ukraine. For the study, 26 well-preserved rather large mounds with a slightly disturbed surface were selected, which had a height of 3–10 m, a diameter of 25–90 m. The mounds are located on chestnut solonetzic soils, in combination with solonetzes and solonchaks. Most of the mounds are located on the territory occupied by desert-steppe and halophytic vegetation (salt marshes, salt licks, saline meadows), which is now unsuitable for crop production (due to salinization) and is used as pastures. Some of the mounds are located among agricultural fields, as well as one each in a park, a reed swamp and in a forest belt near the road. We identified 5 ecotopes on the mounds (top, southern and northern slopes, southern and northern foot), for each of which a separate floristic list was compiled using a 3-point abundance scale. Theoretically, the maximum abundance of the species on all mounds and in all ecotopes can reach 390 points (26 x 5 x 3). We used the abundance data to determine species activity on the mounds and to calculate floristic indices. In this publication, given the limited volume, only the most general results of the study of mounds in the desert-steppe zone of southern Ukraine are presented. In the future, we plan to publish our data in more detail [Black Sea Botanical Journal, 2006].
In total, 303 species of vascular plants were identified on 26 mounds, which belong to 191 genera and 48 families. On one mound, a minimum of 48 species were recorded, and a maximum of 103 species (average 84). The families most represented in the flora are Asteraceae, Poaceae, Fabaceae, Chenopodiaceae, Caryophyllaceae, Brassicaceae, Lamiaceae, Scrophulariaceae, Rosaceae, Apiaceae, Boraginaceae (Latin names are given according to Mosyakin & Fedoronchuk, 1999). Among the identified species, 234 turned out to be native, and among the last 117 species were classified as non-synanthropic. In particular, a number of rare species subject to protection were noted on the mounds, since they are included in the World Red List (Allium regelianum A.Becker ex Iljin, Dianthus lanceolatus Steven ex Rchb., Linaria biebersteinii Besser); European Red List (Senecio borysthenicus (DC.) Andrz. ex Czern.); The Red Book of Ukraine (Anacamptis picta (Loisel.) R.M.Bateman [= Orchis picta Loisel.], Stipa capillata L., Tulipa schrenkii Regel.) and the Red List of the Kherson region (Cerastium ucrainicum Pacz. ex Klokov, Muscari neglectum Guss. ex Ten. , Quercus robur L. - the latter, not in a natural setting, but only as planted or wild on a mound in an old abandoned park).
The identified species are represented in different ways on the mounds. The most abundantly represented on the mounds (with a total abundance score of more than 200): Agropyron pectinatum (M.Bieb.) P.Beauv. (242), Artemisia austriaca Jacq. (240), Holosteum umbellatum L. (236), Festuca valesiaca Gaudin s.l. (230), Poa bulbosa L. (214). The majority of identified species (219, which is 72.3%) have a sum of abundance scores less than 26. Another 33 species (10.9%) have a sum of abundance scores in the range of 26-50, 29 (9.6%) - 51- 100, 17 (5.6%) – 101-200. The basis of the natural vegetation cover on the mounds is made up of turf grasses Agropyron pectinatum, Festuca valesiaca, Stipa capillata (107), Koeleria cristata (L.) Pers. (61). In accordance with zonal characteristics, xerophilic salt-tolerant chamephytes Kochia prostrata (L.) Schrad take a significant part in the vegetation cover. (173), Artemisia santonica L. (154), Halimione verrucifera (M.Bieb.) Aellen (70), Camphorosma monspeliaca L. (63) . Among the steppe forbs, the most common (with more than 100 points): Artemisia austriaca, Poa bulbosa, Taraxacum erythrospermum Andrz., Achillea setacea Waldst. & Kit., Falkaria vulgaris Bernh. Short-lived plants (annuals and young perennials) are widespread on the mounds: Cerastium ucrainicum, Consolida paniculata (Host) Schur, Erophila verna (L.) Besser, Holosteum umbellatum, Lamium amplexicaule L., Myosotis micrantha Pall. ex Lehm., Trifolium arvense L., Valerianella carinata Loisel., Vicia lathyroides L. This group of plants in the flora of mounds of the desert steppes dominates in the spectrum of life forms (46.5%), hemicryptophytes prevailing in real steppes occupy only second place (31, 4%). The significant predominance of short-lived plants is partly due to the synanthropization of the flora, but is also an expression of the zonal features of desert steppes, compared to real ones. It is significant, in this regard, that short-lived plants are more common on the driest and warmest “desert” ecotopes - the southern slope (56.0% in the spectrum of life forms of the flora of this ecotope) and the top (54.6%) of mounds, gradually decreasing on their northern and lower parts up to 43.0% in the lower foothills. Ephemeroids are poorly represented in the studied flora. Only one species, Ficaria stepporum P.Smirn., has an abundance score of over 100; Gagea bohemica (Zauschn.) Schult is also noted. & Schult.f., G. pusilla (F.W.Schmidt) Schult. & Schult.f., G. ucrainica Klokov, Muscari neglecta, Ornithogalum kochii Parl. , Tulipa schrenkii. Halophytes Halimione verrucifera, Hymenolobus procumbens (L.) Fourr., Limonium meyeri (Boiss.) O.Kuntze, L. bellidifolium (Gouan) Dumort often invade mounds located in the coastal zone. (=L. caspium (Willd.) Gams), Petrosimonia oppositifolia (Pall.) Litv., Puccinellia bilykiana Klokov, Salsola soda L., Suaeda prostrata Pall. etc., which is a characteristic feature of mounds located in the desert-steppe zone. Halophytic plants grow mainly at the foot of the mound, while the slopes and top of the mound are occupied mainly by steppe plants, which makes them sharply different from the halophytic flora of the surrounding area and the foot of the mounds. In our opinion, steppe “islands” on mounds among coastal halophytic vegetation arose in connection with the ongoing marine transgression, and also, partly, in connection with the abundant spread of irrigated crop production, which led to the halophytization of coastal depressions, as a result, initially built on steppe territories, the mounds found themselves among halophytic vegetation.
The flora of the mounds is characterized by a wide phytocenotic spectrum. The largest number of species is represented by the class Festuco-Brometea Br.-Bl. et R.Tx. 1943 (Latin names of syntaxa are given from: Mirkin, Naumova, 1998 and Matuszkiewicz, 2001). Species of this class, as well as Festucetalia vaginatae Soo 1957 and Polygono-Artemisietea Mirkin, Sakhapov et Solomeshch in Mirkin et al. 1986 are confined mainly to the slopes of the mound. At the base of the mound, depending on its environment, species of halophytic communities are mainly concentrated (Asteretea tripolium Westhoff et Beeftink in Beeftink 1962, Thero-Salicornietea R.Tx. in R.Tx. et Oberd. 1958, Salicornietea fruticosae (Br.-Bl . et R.Tx. 1943) Tx. et Oberd. 1985 em. V.Golub et V.Solomakha 1988 and meadow (Molinio-Arrhenatheretea R.Tx. 1937 em R.Tx. 1970, Althaea officinalis V.Golub et Mirkin in V.Golub 1995, Galietalia veri Mirkin et Naumova !986, Festuco-Puccinellietea Soo 1968) vegetation. Among synanthropic vegetation, the largest number of species are represented by Stellarietea mediae R.Tx., Lohm. et Prsg 1950 and Artemisietea vulgaris Lohm., Prsg et R. Tx. in R. Tx. 1950.
Despite the fact that we selected the best-preserved mounds for study, their vegetation cover turned out to be more or less synanthropized. In total, 69 species of adventitious plants (anthropophytes) were identified on the mounds, which belong to 57 genera and 22 families. On one mound, from 4 to 29 species of adventitious plants were noted (on average 16). Among the adventitious species, archaeophytes predominate (41 species, or 60.0%), which by their origin are mainly associated with the Mediterranean-Iranian-Turanian region. Kenophytes are represented less significantly, there are 28 species (40.0%). Among them there is a large share of American (32.1%) and Asian (35.7%) species. The level of adventitization of the mound flora depends on the use of the territory that surrounds it. Among the studied mounds, the largest proportion of anthropophytes is on mounds located among agricultural fields. The main factor in the adventitization of the flora of mounds, which are under weak anthropogenic influence, are burrowing wild animals, which, in the course of their life activities, disturb the surface of the mound and create ecotopes suitable for the growth of anthropophytes.
Thus, today many mounds are a refugium of steppe vegetation in the agricultural landscapes of southern Ukraine, and obviously in the steppe part of Eurasia in general. In addition, in the conditions of the coastal desert steppes of southern Ukraine, mounds often act as a refugium steppe flora, but already in the situation of the advancing marine transgression of the last millennia, since some of them, originally built on steppe territories, ended up among coastal halophytic vegetation. In recent decades, intensive agricultural activities in the region have also contributed to the salinization of coastal areas. The differentiation of ecotopic factors can be seen on the mounds, which makes their flora quite rich. The part of the mound - the top and bottom - is usually more anthropogenically altered, which contributes to the concentration of synanthropes there. More favorable conditions for steppe vegetation cover are on the slopes, where steppe species and communities are mainly preserved.

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I. Moisienko, B. Sudnik-Wojcikowska