Not all know what mosses are (the name of the species, genus). In the best case, the familiar cuckoo flax or sphagnum is recalled from a school biology course. In reality, a rather large group of these plants stands completely separate from other existing ones. No bonds or transitional, intermediate forms were found. In ordinary life, not only the names of mosses and lichens are often confused, but also the plants themselves, meeting them, for example, in the forest. Why not take a closer look at these amazing inhabitants of planet Earth.
Mosses - one of the oldest plants on Earth.
The Mossy Department unites a large group of higher plants, which has about 25,000 species. Of these, only 1,500 species grow in our country. Estimates are approximate, as very large tracts of rainforest have not yet been studied. There is even a separate science that deals with the study of mosses - bryology. The oldest fossil forms date back to the Carboniferous times, but scientists assume that they appeared even earlier. These are the only plants whose evolution is associated with the regressive development of sporophyte. They were still at the dawn of the development of life on Earth, firmly taking their place in the plant world and still retain it.
Twenty-two species from the Mossy department are listed in the Red Book of Russia: Krylova Campilium, Orchid Orchidium, Sathieux Brioxifium, Clover Clover, Atractylocarpus Alpine, Marcius Oreas, Tianshi Indusella, Curly Lapwing, Common Lapwing, Lepidoptera smooth-toothed homaliadelphus, northern necker, dull plagiotherium, alternating taxifillum, Hooker actinotuidium, southern alpine leptopterinandrum, wrapped hyophila, alaskan fossombronium nskaya, backgammon Japanese, izopahes discolored.
General characteristics of mosses
The concepts of moss (the Latin name is “bryophyte”) and Mossy are very extensive and unite many species. Basically, these are stunted perennials with a height of 1 mm to several centimeters, but there are species reaching 60 cm or more. A distinctive feature of mosses is the complete absence of the root system. Their function is performed by special outgrowths of the epidermis - rhizoids. With their help, the body of the moss attaches to the substrate and receives water with minerals dissolved in it. The breeding cycle consists of the sexual (gametophyte) and asexual (sporophyte) generation. On the one hand, regressive signs pushed them far back in comparison with other plants on the planet, and on the other, they allowed them to survive in the most severe conditions when everyone else died out. This is also due to the fact that they initially took their place under the cover of other plants, therefore they are neutral in regard to both lighting and heat. The main factor for mosses is the presence of moisture. But even to her lack they managed to adapt. There is another amazing feature of mosses - the ability to fall into a state of suspended animation under adverse environmental conditions. At this point, the plant almost stops all life processes. Mosses can be in a state of suspended animation for decades, successfully surviving extremely low or high temperatures, lack or absence of moisture.
Moss spread
These plants are very fond of humid places, they are spread almost all over the world, except for the seas and strongly acid (saline) soils. Especially often, various types of mosses, whose names are sometimes difficult to translate from Latin, are found in the tundra. They grow quite slowly (annual growth of 1-2 mm), if you take one separate plant, but, in general, a very significant biomass is obtained.
The fact that mosses inhabit almost all corners of the planet is also explained by the fact that these are oligotroph plants. They can grow even on the poorest and poorest soils. Animals, as a rule, do not eat mosses. Their ability to actively retain moisture sometimes leads to waterlogging of the soil.
Reproduction of mosses
These plants have a peculiar breeding cycle. The names of mosses and their distribution are different, but they are all similar in that a gametophyte and sporophyte are combined in one plant. The latter is also called the asexual generation. It is represented by a small box with spores, which is attached to the gametophyte with the help of a suction cup. The development of the sexual generation originates from the moment of spore germination. Initially, a filamentous or lamellar formation (protonema) develops, on which the buds are laid, from which then the lamellar thallus or stems with leaflets grow, depending on what types of mosses they are. The names of the organs of sexual reproduction of higher plants are familiar to many from school - these are archegonies and anteridia. The first are female reproductive organs, characteristic of higher spore plants, as well as the gymnosperm order. Anteridia are male organs; they are found in higher plants and algae.
Classification
Let us dwell in more detail on the question of what mosses are. The name of the two existing classes are very unusual: hepatic and leaf-stem. Earlier in the classification, Antocerotic mosses were also included. But later, scientists came to the conclusion that these are different groups of plants and allocated them to a special department. Each class has its own specific features and characteristics.
Class Hepatic or Hepatic: types of mosses, names and photos
A distinctive feature of all species of these plants is a wide variety of gametophytes and similarity of sporophytes. The total class size is about 300 genera and 6,000 species of mosses. They grow mainly in a tropical climate. Vegetative propagation by more or less developed parts of the thallus is very characteristic of them.
There are species that are not fixed neither on the soil, nor on the trees, for example, floating rich. In natural conditions, it is found in the Far East and Ciscaucasia. Sometimes it is also bred in aquariums.
Diverse marching is also quite common in Russia. This moss grows on the soil. The body of the plant (thallus) has the form of a multilayer, highly branching plate and sizes up to 10 centimeters. The plants are dioecious, and the reproductive organs are placed above the plate on special supports in the form of an umbrella.
What are the generic names of the liverwort moss class? We list some of them: spherocarpus, pallavicinia, symphiogine, mercury, hymenophytum, metzgeria, riccia.
Class Leafy mosses: examples, names
Leafy mosses are the largest class, which includes more than 15,000 species, combined in 700 genera. In addition to their multiplicity, they also have an important role in the plant cover of the Earth. Gametophyte in representatives of this class can grow vertically upwards or in a horizontal plane. Depending on this, they are divided, respectively, into orthotropic and plagiotropic species. Leafy mosses for convenience were divided into three subclasses: sphagnum, andreev, and shave.
Subclass Sphagnum Mosses
Everyone knows these names of mosses. There are more than 300 species of plants included in the subclass (40 species are found in our country), and they grow around the world. All representatives of the species are quite large in size and color white-green, brown or red. Basically, the species of this subclass comprise the vegetation of the tundra zone and are the main source of the formation of peat deposits.
The genus Sphagnum, or peat moss, includes 120 species. They all grow in swamps, covering them with a continuous carpet. The stems give an annual growth of 2-3 cm, while the lower part dies and decomposes, but does not rot. The reason for this feature is that carbolic acid is formed in the body of the moss, which is an antiseptic. The dead part forms peat, but this process is very slow. So, it was calculated that 1 meter of such deposits is formed within 1,000 years!
Another representative of the subclass under consideration is the rural tortula. This moss grows on trees, the name has an unusual. Habitat: from the tundra to the zone of arctic deserts. It is fixed on the bare roots of trees and bark, as well as stones. It has a characteristic brown or greenish-brown color, the stem grows up to 10 centimeters.
Here are some names of mosses of this genus: marsh sphagnum , protruding, brown, hirgenzona, Magellan, papillosis.
Subclass Shavemoss
The subclass is quite numerous and includes more than 14,000 species, 1,300 of which are found in Russia. Basically, these are perennial plants, reaching very impressive sizes: from 1 mm to 50 cm in height. The color is usually green, reddish brown or even almost black. They grow, as a rule, on the soil, rotten trees or on leaves. They absolutely cannot stand salty soils. Everyone is familiar with such names of mosses in Russian as cuckoo flax, or scientifically polytrichum ordinary, hairy brim. They grow in the northern and central strip of Russia, most often in the forest.
Subclass Andreev
This is a group of small plants (about 120 species) growing in cold climatic conditions (Arctic and Antarctic). They can be found on stones and rocks, on which they form something like pillows. Representatives of this subclass are Andrei Skalnaya, splahnum red and yellow, rosacea rosette, leucobrium bluish, drooping polia, centipede dicranum. These are just some types of mosses. The names and photos of the remaining representatives of the subclass can be found in the botanical atlases, which will also give a detailed description of the genus and species.
Antotserotovy department
Antrozerotovye previously considered as mosses and stood out in a separate class. Now they are defined as mossy plants with a similar tall structure. The thallus is characterized by a rosette-shaped form, on the underside there are rhizoids. These are inhabitants of the tropics, and only a few species grow in temperate climates.
How to distinguish moss from lichen?
People often confuse not only the names of mosses and lichens, but also their appearance in general. The main difference is that the latter are representatives of lower spore plants that appeared on Earth much earlier than mosses. Some lichens even have a name that directly indicates belonging to a completely different group of plants. For example, oak moss, Irish moss, deer moss. The names have remained the original, but they have no relation to the department under consideration. Oak moss has the beautiful scientific name Evernia Plum. If you look at the photo, it will immediately become clear that this is a lichen. It grows, as the name implies, on oak bark, as well as some coniferous plants.
The body of lichens is a symbiosis of algae and fungus. They have no roots, and mosses have their likeness - rhizoids. Simply put, the body of a lichen is like a sandwich: on top and bottom there is a mushroom, and in the middle are algae, which carry out the process of photosynthesis. The substrate to which the lichen is attached (most often trees) is destroyed by the action of a special acid, which is secreted by the fungi. Moreover, it can even destroy stone. Therefore, these plants are quite harmful. So, when they appear, for example, on fruit trees, they simply destroy the bark. But at the same time, lichens are an indicator of air purity, because they absolutely do not tolerate gas contamination.
What are ferns and mosses like?
Ferns in evolutionary terms stand one step higher than mosses. This is explained by the fact that they have a vascular conducting system through which water and minerals dissolved in it enter the plant. They are more familiar to people and are found everywhere in the forests. The thyroid and bracken are well-known names. Mosses and ferns are nevertheless united by one significant similarity: they both reproduce not by seeds, but by spores. That is, there is an alternation of sexual and asexual generation (sporophyte and gametophyte). In addition, they are very often neighbors in the natural habitat, as both of them prefer shade and high humidity.
The value of mosses
Mosses in the natural environment are pioneers, they are the first to populate territories whose climatic conditions are sometimes not suitable for any other plant. These plants are an integral part of the entire biosphere as a whole. Mosses create special biocenoses in the tundra, covering the earth with a continuous carpet.
They have a very pronounced ability to retain moisture, the benefits of which can be interpreted from two sides. From the first point of view, they regulate the water balance in the soil, and from the second point of view, they contribute to the swamping of forests, meadows and agricultural lands.
Sphagnum mosses are a valuable source for the formation of peat deposits, which is widely used as fuel, material for construction, and in agriculture. In addition, some species are used in medicine, as they have antibacterial properties. But the formation of sphagnum and hypnous bogs is essential for the entire ecosystem as a whole. It is the place of growth of many shrubs and herbaceous plants, home to numerous game animals and birds. But most importantly, the swamp is a kind of reserve tank with fresh water. After all, like a sponge, absorbing all the rainfall, it gradually then gives moisture into the soil to small streams that flow from it. The swamp acts as a regulator of humidity in the surrounding area.