Pipe structure Water and gas pipes are made by butt welding with a nominal bore diameter Bu from 6 to 150 mm, a wall thickness S from 1.8 to 5.5 mm, a length from 4 to 12 m. At the customer's request, metric threads are cut at the ends of the pipes. The ends of the pipes are cut at right angles to the axis

2.1. Gooseberry structure 2.1.1. Root system Cultivated plants have two types of roots. Seedlings obtained from seeds have a main branched root that does not grow to great depths, spreading no deeper than half an arshin (35 cm), because it is the same with it

After reading this article, you will learn what lichen consists of, what forms of these plants are found, as well as what role they play in nature and in human economic activity. We will also tell you how they absorb moisture and describe their metabolism.

Where do lichens grow?

Lichens are adapted to life even in the harshest conditions; they often establish themselves in places where other living organisms cannot exist. They extend further north and south than other plants. In the Himalayas they were found at altitudes above 5600 m.

Lichens, of which there are numerous examples, can exist on almost any surface, be it a sun-scorched rock, an arid desert, the back of a beetle, or the bleached bone of a dead animal. One species (Verrucaria serpuloides) lives by immersing itself in the icy waters of Antarctica for a long time, while another (Lecanora esculenta) is carried by the wind. And although in general lichens are very sensitive to all kinds of industrial waste, a species such as Lecanora conizaeoides noticeably thrives in rather polluted places.

Lichen forms

In accordance with their growth characteristics, all known species of these plants (and there are 15,000 of them) are divided into three main groups. Let's briefly describe each of them.

Foliates thrive in areas that receive high rainfall. As you may have guessed, they are named so because they are shaped like leaves. One of their types is shown in the photo below.

The next group is scale (crust). They are resistant to drought and therefore predominate in deserts. tightly adhere to the substrate on which they grow. Caloplaca heppiana, for example, is often found on walls and gravestones. This and a number of similar plant species of interest to us are used as indicators of the age of the substrate. Lichens of this group are often brightly colored, and the fungus is pigmented.

And finally, bushy plants are able to take moisture from the air and are found mainly in humid climate zones. The sizes and appearance of the plants that interest us are very diverse. Some of them form threads 2.75 m or more in length, while others are no larger than the head of a pin.

What does lichen consist of?

These organisms are formed from plants belonging to two different divisions: algae and fungi. Let's tell you more about what lichen consists of. It is one of the most successful examples of mutualism. This term refers to a mutually beneficial partnership that can be established between two dissimilar organisms.

The algal component is a necessary element of what lichen consists of. This is usually either green or blue-green algae. The fungal component is a representative of ascomycetes. With rare exceptions, lichens include only those plants that consist of one type of fungus and one type of algae. Of the latter, the composition of these plants most often (in more than 50% of species) includes the unicellular green alga Trebouxia, but there may also be others.

So, lichens include organisms consisting of a fungus and an algae that are in mutually beneficial cohabitation. Let's give another example. Xanthoria parietina (pictured below) is usually found on rocks along sea coasts, as well as on walls and roofs of houses. Its orange saucer-shaped fruiting bodies (apothecia) are almost indistinguishable in structure from the fruiting body of an isolated mushroom.

A thin top layer of tightly intertwined fungal hyphae can be seen in a cut of lichen. It contains individual cells of green algae. Basically, a lichen is an organism whose body consists of loosely intertwined fungal hyphae, below which there is another thin layer of hyphae, similar to the top one.

Lichen growth

They grow very slowly. Most scale species rarely increase in size by more than 1 mm per year. Other forms of lichens grow a little faster, but they also add no more than 1 cm per year. It follows that the large species of these plants are of a very respectable age; It is believed that individual representatives of some Arctic species are older than 4000 years.

Using the so-called lichenometry, i.e. measuring lichens, they even determine the age of the surface of rocks. This method established the age of glaciers, as well as giant megaliths (large blocks of stone). The latter were found on Easter Island in the Pacific Ocean.

The advanced age of these plants shows that they have a fairly high organization and that the relationship between algae and fungus is well balanced. But the true nature of this relationship is not yet entirely clear.

Metabolism

Photosynthetic algae, like other green plants, provide food for both partners, since the fungus does not have chlorophyll. Simple carbohydrates synthesized by the algae are released by the algae and absorbed by the fungus, where they are converted into other carbohydrates. This carbohydrate metabolism underlies the symbiotic relationship that led to the formation of lichen. The transfer of nutrients from algae to fungus occurs very quickly: it was found that fungi manage to convert sugars coming from algae within three minutes from the moment photosynthesis begins.

Moisture absorption

Lichens, absorbing a lot of moisture, change significantly in volume. Their height increases significantly. There is no separation of organs that give and absorb moisture in these plants. The cortex performs both of these functions. Lichens also do not have devices that protect them from transpiration, which are well developed, for example, in vascular plants. Most of the organisms we are interested in receive moisture from the air, and not from the soil. They absorb water vapor. Only some species that attach to the substrate have the ability to take part of the moisture from it.

Use of lichens

Lichens have a variety of uses in nature: they serve as food for animals (for example, they make up two-thirds of the diet of reindeer), are used as nesting material by birds, and provide shelter for many species of small invertebrates such as ticks, beetles, butterflies and snails. They also bring benefits to humans. Extracts from lichens were once used to dye fabrics from which they were sewn. They produced yellow, brown, red and purple
paints. Intermediate colors were obtained by additional dyeing.

(Cetraria islandica) has been used as a cough suppressant for over two centuries. Usnic acid present in some lichens is used by humans to treat superficial wounds and tuberculosis.

Modern research has discovered that they contain antibiotics that are effective against diseases such as pneumonia and scarlet fever. In addition, these plants are used in industry. Thus, from the lichen Roccella sp. a special litmus is obtained - a chemical indicator that turns red in an acidic environment and blue in an alkaline environment.

This is a unique group of lower plants, which consist of two different organisms - a fungus (representatives of ascomycetes, basidiomycetes, phycomycetes) and algae (green - cystococcus, chlorococcus, chlorella, Cladophora, palmella are found; blue-green - nostoc, gleocapsa, chroococcus), forming a symbiotic cohabitation , characterized by special morphological types and special physiological and biochemical processes. Some lichens were thought to contain bacteria (Azotobacter). However, later studies did not confirm their presence in lichens.

Lichens differ from other plants in the following ways:

1. Symbiotic cohabitation of two different organisms - a heterotrophic fungus (mycobiont) and an autotrophic algae (phycobiont). Lichen cohabitation is permanent and historically conditioned, and not accidental, short-term. In a true lichen, the fungus and algae come into close contact; the fungal component surrounds the algae and can even penetrate its cells.
2. Specific morphological forms of external and internal structure.
3. The physiology of fungi and algae in the lichen thallus differs in many ways from the physiology of free-living fungi and algae.
4. The biochemistry of lichens is specific: they form secondary metabolic products not found in other groups of organisms.
5. Reproduction method.
6. Attitude to environmental conditions.

Morphology. Lichens do not have a typical green color, they do not have a stem or leaves (this is how they differ from mosses), their body consists of a thallus. The color of lichens is grayish, greenish-gray, light or dark brown, less often yellow, orange, white, black. The coloring is due to pigments that are found in the membranes of the fungal hyphae, less often in the protoplasm. There are five groups of pigments: green, blue, violet, red, brown. The color of lichens may also depend on the color of lichen acids, which are deposited in the form of crystals or grains on the surface of the hyphae.

Lichens are classified as crustacean, or crustaceous, leafy, and bushy.

U scale the thallus has the appearance of a powdery, lumpy or smooth skin that tightly fuses with the substrate; about 80% of all lichens belong to them. Depending on the substrate on which crustose lichens grow, they are distinguished: epilithic, developing on the surface of rocks; epiphleoid - on the bark of trees and shrubs; epigeic - on the soil surface, epixyl - on rotting wood.

Thallus lichen can develop inside a substrate (stone, tree bark). There are crustose lichens with a spherical thallus (the so-called nomadic lichens).

U leaf lichens the thallus has the form of scales or rather large plates, which are attached to the substrate in several places with the help of bundles of fungal hyphae. The simplest thallus of leaf lichens has the appearance of one large rounded leaf-shaped blade, reaching a diameter of 10-20 cm. Such a thallus is called monophyllous. It is attached to the substrate in its central part with the help of a thick short stalk called a gomph. If the thallus consists of several leaf-shaped plates, it is called polyphilous. A characteristic feature of the leaf thallus of lichens is that its upper surface differs in structure and color from the lower. Among leaf lichens there are also non-attached, nomadic forms.

U fruticose lichens the thallus consists of branched threads or stems, fused with the substrate only at the base; grow upward, to the side, or hang down - “bearded” lichens. The thallus of fruticose lichens has the appearance of an erect or hanging bush, less often of unbranched erect outgrowths. This is the highest stage of development of the thallus. The height of the smallest is only a few millimeters, the largest - 30-50 cm (sometimes 7-8 m - long usnea, hanging in the form of a beard from the branches of larches and cedars in taiga forests). Thallus come with flat and rounded lobes. Sometimes large bushy lichens in tundra and highland conditions develop additional attachment organs (hapters), with the help of which they grow to the leaves of sedges, grasses, and shrubs. In this way, lichens protect themselves from being torn off by strong winds and storms.

Based on their anatomical structure, lichens are divided into two types.

• In one of them, the algae are scattered throughout the thickness of the thallus and are immersed in the mucus that the algae secretes (homeomeric type). This is the most primitive type. This structure is typical for those lichens whose phycobiont is blue-green algae - nostoc, gleocapsa, etc. They form a group of slimy lichens.
• In another (heteromeric type), several layers can be distinguished under a microscope in a cross section. On top is the upper cortex, which has the appearance of intertwined, tightly closed mushroom hyphae. Underneath it, the hyphae lie more loosely, with algae located between them - this is the gonidial layer. Below, the mushroom hyphae are located even more loosely, the large spaces between them are filled with air - this is the core. The core is followed by the lower crust, which is similar in structure to the upper crust. Bundles of hyphae pass through the lower bark from the pith and attach the lichen to the substrate.

Crusted lichens do not have a lower bark and the fungal hyphae of the cores grow directly with the substrate.

In bushy radially built lichens, at the periphery of the cross section there is a bark, under it there is a gonidial layer, and inside there is a core. The bark performs protective and strengthening functions. Attachment organs are usually formed on the lower crustal layer of lichens. Sometimes they look like thin threads consisting of a single row of cells. They are called rhizoids. Rhizoids can join together to form rhizoidal cords.

In some leaf lichens, the thallus is attached using a short stalk (gomph), located in the central part of the thallus.

The algae zone performs the function of photosynthesis and accumulation of organic matter. The main function of the core is to conduct air to the algae cells containing chlorophyll. In some fruticose lichens, the pith also performs a strengthening function.

The organs of gas exchange are pseudocyphellae (ruptures in the cortex, visible to the naked eye as white spots of irregular shape). On the lower surface of leaf lichens there are round, regular-shaped white depressions - these are cyphellae, also organs of gas exchange. Gas exchange also occurs through perforations (dead sections of the crustal layer), cracks and breaks in the crustal layer.

Nutrition

Hyphae play the role of roots: they absorb water and mineral salts dissolved in it. Algae cells form organic substances and perform the function of leaves. Lichens can absorb water over the entire surface of the body (they use rainwater and fog moisture). An important component in the nutrition of lichens is nitrogen. Those lichens that have green algae as a phycobiont receive nitrogen compounds from aqueous solutions when their thallus is saturated with water, partly directly from the substrate. Lichens that have blue-green algae (especially nostoc algae) as a phycobiont are capable of fixing atmospheric nitrogen.

Reproduction

Lichens reproduce either by spores, which are formed by the mycobiont sexually or asexually, or vegetatively - by fragments of the thallus, soredia and isidia.

During sexual reproduction, sexual sporulation in the form of fruiting bodies is formed on the lichen thalli. Among the fruiting bodies in lichens, apothecia are distinguished (open fruiting bodies in the form of disc-shaped formations); perithecia (closed fruiting bodies that look like a small jug with a hole at the top); gasterothecium (narrow, elongated fruiting bodies). Most lichens (over 250 genera) form apothecia. In these fruiting bodies, spores develop inside bags (sac-like formations) or exogenia, at the top of elongated club-shaped hyphae - basidia. The development and maturation of the fruiting body lasts 4-10 years, and then for a number of years the fruiting body is capable of producing spores. A lot of spores are formed: for example, one apothecium can produce 124,000 spores. Not all of them germinate. Germination requires conditions, primarily certain temperature and humidity.

Asexual sporulation of lichens - conidia, pycnoconidine and stylospores that arise exogenously on the surface of conidiophores. Conidia are formed on conidiophores developing directly on the surface of the thallus, and pycnoconidia and stylospores are formed in special containers - pycnidia.

Vegetative propagation is carried out by thallus bushes, as well as by special vegetative formations - soredia (specks of dust - microscopic glomeruli, consisting of one or several algae cells surrounded by fungal hyphae, forming a fine-grained or powdery whitish, yellowish mass) and isidia (small, variously shaped outgrowths of the upper surface of the thallus , the same color as it, look like warts, grains, club-shaped outgrowths, and sometimes small leaves).

The role of lichens in nature and their economic importance

Lichens are pioneers of vegetation. Settling in places where other plants cannot grow (for example, on rocks), after some time, partially dying, they form a small amount of humus on which other plants can settle. Lichens are widespread in nature (they live on soil, rocks, trees, some in water, and are found on metal structures, bones, glass, skin and other substrates). Lichens destroy rocks, releasing lichen acid. This destructive effect is completed by water and wind. Lichens are capable of accumulating radioactive substances.

Lichens play an important role in human economic activity: they serve as food for deer and some other domestic animals; certain types of lichens (lichen manna, gyrophora in Japan) are consumed by humans; Alcohol is extracted from lichens (from Icelandic Cetraria, some types of Cladonia), paints (from some types of Rochel, Ochrolechnia); They are used in the perfume industry (evernia plum - oak "moss"), in medicine (Icelandic "moss" - for intestinal diseases, for respiratory diseases, lobaria - for pulmonary diseases, peltigera - for rabies, parmelia - for epilepsy, etc. ); Antibacterial substances are obtained from lichens (the most studied is usnic acid).

Lichens almost do not harm human economic activity. Only two poisonous species are known (they are rare in our country).

Lichens are a group of living organisms.

Their body is composed of a combination of two microorganisms that are in a symbiotic relationship: a fungus (mycobiont) and an algae (phycobiont or cyanobacteria).

general characteristics

The science of lichenology, which is a department of botany, studies this species.

For a long time, lichens were a mystery to scientists, although their use was widespread in various sectors of human life. And only in 1867 the structure of this species was scientifically proven. Scientists-lichenologists were engaged in this.

At the moment, scientists have discovered more than 25 thousand species, but they all have a similar external and internal structure. The characteristics by which each species should be distinguished are based on structural features.

What does lichen look like?

As already mentioned, the main part of the species is the body, characterized by a variety of shapes and colors. In this case, the growth can be a plate, a crust that looks like a leaf, in the form of a bush, tube or ball.

The height of the plant also varies within fairly wide limits: starting from 3 centimeters and ending with the height of a person.

Types and names of lichens

Lichenology has divided lichens into several groups depending on the shape of the thallus:

In addition, based on the place where they grow, there are:

• epigean (mainly on a land base);
• epiphytic (on a woody base);
• epilithic (on stone).

Features of the internal structure

It seems possible to see the structure of the lichen under a magnifying device. A lichen is an organism consisting of part of a fungus - mycelium and algae intertwined with each other.

Depending on how the cells of algae and fungi are distributed among themselves, another classification is distinguished:

• homeomeric, in which the phycobiont is located chaotically among the mycobiont cells;
• heteromeric, in which there is a clear separation into layers.

Lichens with a layered structure are found everywhere and have the following layer structure:

1. The cortical layer is composed of mycobiont cells and protects from external influences, especially from drying out.
2. Superficial or gonidial: contains exclusively phycobiont cells.
3. The core consists of a mushroom, serves as a skeleton, and also helps retain water.
4. The lower cortex serves as an attachment to the base.

It is worth noting: in some species, some types of layers may be absent or have a modified structure.

Where do they live?

Lichens are distinguished by their ability to adapt to absolutely any living conditions. For example, they grow on bare stones, rocks, walls and roofs of buildings, tree bark, etc.

This is due to the mutually beneficial cooperation of the myco- and phycobionts included in the composition. The life activity of one complements the existence of the other, and vice versa.

How do lichens feed?

Nutrition is provided by symbiotes. Since fungi do not have the function of autotrophic nutrition, during which the process of converting organic components from inorganic ones occurs, algae supply the body with the necessary elements.

This happens through photosynthesis. And the fungus supplies the lichen with mineral salts, which it absorbs from the incoming liquid. This is how the process of symbiosis occurs.

How do they reproduce?

They reproduce in two ways:

1. Sexual reproduction occurs through sporulation.
2. Vegetative - for this there are soredia (an algae cell entwined with a thread of mycelium, which is carried by the wind) and isidia (outgrowths that form the surface layer of the thallus).

The importance of lichens in nature and human life

They have the following positive effects:

Lichens are famous for their lifespan, because the growth period alone can reach 4 thousand years.

As a result, they can be used to approximately determine the age of the rock.

Their use as fertilizer in the agricultural industry is popular. In addition, their use began in ancient times. Lichens were used as natural dyes.

Lichens are a unique species that carries a lot of useful properties and qualities that are applicable in virtually any sector of human life.

The lichen class is one of the most widespread and diverse organisms on Earth. Science knows more than 25 thousand of their species; their distribution system is still not fully understood. Their system consists of two elements: fungus and algae; it is this composition that unites a huge variety.

What are crustose lichens?

The name “lichens” comes from an analogy with the disease lichens, which arises due to their appearance. Lichens are representatives of a unique species, known for the fact that they simultaneously contain two organisms, an algae and a fungus. Many scientists allocate a separate class for this. Their combination is unique: the fungus inside its body creates a special habitat in which the algae is protected from external influences and provided with liquid and oxygen. The fungus consumes water from the substrate, absorbs oxygen, so the algae inside it receives nutrition and feels comfortable. Their existence does not require special soil; they grow wherever there is air and water, even in minimal quantities. Representatives of crustose lichens cover bare rocks, stones, grow on clay, on roofs and trees.

Areas where crustose lichens grow

Lichens are one of the most widespread microorganisms on the planet. In almost every latitude you can find crustose lichens that can adapt to any conditions. Adapted to cold weather, they thrive on the slopes of polar cliffs and are comfortable in the tropics and deserts.

Crustose lichens are distributed throughout the planet and do not require unique, specific conditions. Depending on the type of substrate and climate characteristics, one or another species grows in the area. As they grow, they cover huge areas, completely filling the slopes of rocks and covering the stones.

As a rule, groups are tied to climatic conditions or to a natural area. Some species can only be found in the Arctic, others only in the taiga. But in this system there are a number of exceptions when the geography of growth is associated with environmental conditions that are repeated in different regions. These lichens live on the shores of freshwater lakes, oceans, mountains, etc. Also, the distribution may be tied to certain soil characteristics: some groups of lichens grow on clay, others on rocky soil, etc.

Implications for ecology

They are found everywhere in the planet's ecological system. The importance of lichens is great; these organisms perform a whole layer of work. They occupy a crucial place in the formation of the soil; they are the first to penetrate the layers and enrich it for the further growth of other species. Crustose lichens do not need a special substrate; covering the territory of infertile soil, they enrich it and make it suitable for the life of other plants. During the growth process, they release special acids into the soil, due to which the soil becomes loose, weathered and enriched with oxygen.

The favorite growing environment for crustose lichens, where they feel comfortable, is rocks. They confidently attach themselves to rocks and cliffs, change their color, gradually creating conditions on their surface for the development of other species.

Many animals have colors that correspond to one or another type of lichen growing in their habitat. This allows them to camouflage and protect themselves from predators.

External structure

The appearance of these symbiotic fungi is extremely varied. Lichens, crustose or crustose, are so called because they create a crust resembling scale on the surface where they grow. They can take different shapes and have unexpected colors: pink, blue, gray, lilac, orange, yellow or others.

Scientists distinguish 3 main groups:

Scale;

Leafy;

Bushy.

Characteristic signs of crustacean lichens are that they grow firmly to the ground or other substrate; it is impossible to remove them without damage. Such lichens are most common in cities, where they can grow on concrete walls and trees. They can also often be found on slopes. Wherever these lichens are found, their crustose varieties do not require any essential conditions and feel great even on stones.

They are a crust that covers surfaces unsuitable for life of other plants. Due to the peculiarities of their structure and appearance, they can be completely invisible and merge with nature. It is a mistake that all such mushrooms are just one of thousands of varieties of lower plants.

It is very easy to distinguish crustose lichens from other species. Leafy ones are attached to the soil with the help of sprouts that resemble small stems. The body of the lichen itself has a leaf-like appearance of various shapes, their sizes can also fluctuate.

Bushy ones have the most complex external shape. They consist of twigs, round or flat, and can grow on the ground and rocks. They are the largest, and as they grow, they can also hang from trees.

Crumbose lichens may have a transitional position between these groups and features of other species: this classification is focused solely on their external characteristics.

Internal structure

The body of crustose lichen, or thallus (thallus), comes in two types:

Homeomeric;

Heteromeric.

The first type is the simplest, in it the algae cells are contained in a chaotic order and are distributed quite evenly between the hyphae of the fungus. Most often, this structure can be found in slimy lichens, for example, in crustose lichens of the genus Collema. In a calm state, they look like dried crusts, and under the influence of moisture they instantly swell, taking on the appearance You can meet them on the Black Sea coast.

The heteromeric thallus of lichen has a more complex structure. Most crustose lichens belong to this type. In the context of this type, its structured internal organization can be traced. The top layer forms a mushroom, thus protecting the algae from drying out or overheating. Below the fungus has branches that are attached to the algae cells. Below is another layer of the vulture, which is a substrate for algae, with its help the required level of humidity and oxygen is maintained.

Lichen groups

According to the type of growth and attachment to the type of substrate, the following groups are distinguished among crustose lichens:

Epigeal;

Epiphytic;

Epiletaceae;

The first group, epigeic lichens, are common on various soils; they also grow well on stumps and rocks. They can easily withstand competition with plants of higher groups, so they grow infrequently on poor soils, preferring fertile soil. Some of them grow in dry swamps, along roads, in the tundra, where they occupy vast territories, etc. The most famous species are Lyceum, Pertusaria, Ikmadofida.

Epigeal lichens can also be divided into two more categories: moving (belong to other species) and soil-fixed lichens, which are mostly crustacean. Attached scale can exist on sandy, limestone, and clay soils. The names of crustacean lichens in this group are as follows: twisted ramalina, dark brown parmelia, collema, pink beomycets and others.

Epiphytic lichens grow exclusively on trees or shrubs. They are also conventionally divided into two groups: epiphilic (exist on leaves, bark) and epixyl, arising on fresh cuts. In most cases, they are found precisely on the bark; a couple of dozen different types of crustose lichens can simultaneously coexist in a tiny area, completely changing the color of the tree and creating a new external surface.

Crustose lichens of the epilithic group settle on stones and rocky rocks. Their examples are diverse: some grow exclusively on limestones, others prefer silicon rocks, others settle here and there, as well as on city roofs and walls.

Types of crustose lichens

Crustose lichens come in all four types accepted in science: epilithic, epigeic, epiphytic and epixyl. They can grow on tree trunks, on dead wood, on stumps, but most often they grow on bare rocks.

Crustose lichens grow on a variety of substrates. Examples can easily be found in any city or forest: on walls, roofs, stones, cliffs. They grow so tightly to the soil that it is impossible to remove them without damaging them.

Crustose lichens form a crust similar to scale. They can have a wide variety of colors, and, completely covering a landscape object, significantly change its appearance. Pink and purple rocks make the landscapes bright and unusual.

Aspicilia, hematoma, lecanora, lecidea, graphis, biatora are the most well-known crustacean lichens; examples of their growth are found almost throughout the country. A species of biator can exist simultaneously in swamps and on rocks. Lecanora crustose lichen, for example, can grow on various substrates: on stones, trees or stumps.

Reproduction of crustose lichens

There are three methods of reproduction: vegetative, sexual or asexual. Sexual reproduction is one of the most common methods: lichens form apothecia, perithecia or gasterothecium - these are various bodies within the body in which spores develop. Their development is extremely slow and can last up to 10 years. After this process is completed, gasterothecium begins to produce spores, which subsequently germinate at the right temperature and humidity.

With asexual sporulation of lichens, spores arise and develop directly on the surface.

Vegetative propagation involves tiny substances consisting of particles of algae and fungus, and thallus bushes. They are spread by wind or animals, traveling until they find a suitable substrate. This is the fastest method of reproduction, facilitating rapid spread. Reproduction in this way can also occur with an unprepared piece of lichen, but in this case the chances of growth on a new substrate will be lower.

Application

The use of crustose lichens is unusually wide: they are able to grow where no other plant has a chance. Over time, they prepare the necessary environment, a sufficient amount of humus, for the growth of other plants. At the same time, of the entire multi-thousand variety of lichens, only two species are poisonous, the rest find their use in different fields: in agriculture, medicine.

The use and importance of lichens in pharmacology is also great: healers in villages know the beneficial properties of each of hundreds of species, using them to treat a wide range of diseases: from coughs to oncology. Scale lichens are especially effective in treating purulent inflammation. They are carefully cut off from the surface and applied to the wound - thanks to the antibacterial properties and antiseptics contained in their composition, they destroy bacteria and promote cleansing and healing of the open wound.

Measuring environmental health using lichens

In science, they are also used to study environmental conditions and air quality. Crustose lichens are the most resistant to deteriorating natural conditions; they tolerate environmental disasters and high levels of air pollution, but this significantly affects their condition. Due to the peculiarities of their structure, lichens absorb incoming water and air without additional filters, with the entire thallus at once. Because of this, they are sensitive to pollution and changes in air or water composition, as toxins instantly disrupt their internal functioning.

Due to the increased content of toxic substances in the atmosphere or water, cases of mass death of crustose lichens occur. The first such cases began to occur near large industrial cities, where production is developed, and, consequently, there is a high level of air pollution. These cases clearly demonstrated the need to filter emissions of harmful substances into the air. Today, lichens are growing again in major cities thanks to environmental concerns and improved air quality.

There are two directions for studying the state of air according to the state of representatives of this species: active and passive. With passive, conclusions are drawn about the state of the atmosphere here and now; active involves a long-term study of a certain type of lichen, which makes it possible to obtain a more accurate picture.