The ecosystem, by and large, to a small extent depends on the vital activity of the vegetation of the lower groups. Mostly a positive influence is exerted by some representatives of the upper class. There are exceptions among algae. These include the Charova algae department, which has existed since ancient times. Another thing is that today this group is not represented by species as widely as other representatives of the kingdom. By the way, algae of this category are called harophytes.
General information about the Char group
Externally, algae are massive branching plants that have many differences from the rest of the kingdom. If we approach superficially the analysis of the structure of representatives of this group, then it is quite possible to confuse them with the higher classes of vegetation. This is due to the fact that the Khara combine the characteristics of lower algae and higher plants, which is also manifested in their functions. It is important to note that there are different types of this group, united in a genus. To date, the following examples of char algae are distinguished: Hara Asper, Nitella Flexilis, Nitella Sinkarp, etc. Some species gravitate toward life near water bodies, while others are found in sea bays and continental brackish lakes. Most often, charovy grow in arrays of several representatives, and not one by one. Thus, they form thickets, covering vast areas along the bottom of the reservoir.
Plant taxonomy
For a long time, scientists could not determine with high accuracy which systematic group of plants belong to char algae in their main genera. The fact is that the presence of groups A and B in the chlorophyll cells gave reason to classify plants as representatives of the Chlorophyta department. The presence of starch as a reserve enzyme also supported this classification. According to other studies, algae should have been part of the Charophyta department. The basis for such claims was the early separation of plants from green algae. There was also a point of view that the group can be considered as an intermediate link from bryophytes to green algae. The modern results of biochemical, molecular, and ultrastructural analyzes determine char results as representatives of the Streptophyta department. Zinematical plants fall into the same category.
Main genera
To begin with, it should be noted that there are three main types of these plants. This is directly Hara, as well as Nitella and Tolipella. Representatives of the first kind are characterized by cosmopolitan distribution and prefer shallow water bodies. Their natural habitat is a depth of 1-1.5 m. It is important that the water is clean, not cloudy. In some aspects, this genus can be called the most unpretentious - for example, plants can live in brackish and freshwater conditions. However, polluted water is not suitable for them. As for the genus Nitella, its representatives are more predisposed to fresh water, and also found in reservoirs with a sandy bottom. If charic algae of the first kind does not like substrates, then this genus fully admits such a neighborhood - for example, with silty fragments. Tolipella is also sensitive to pollution, while willingly propagating on sandy soils and mainly in shallow depths.
Habitat
In Russia, this group of algae lives within the West Siberian Plain and Altai. Since the mid-nineteenth century, scientists regularly discover new populations and places in which algae breed. It is noteworthy that in some conditions charovy can even have advantages over representatives of higher plants. For example, this is observed on dry and watered sections of water bodies. To date, 17 species of Chara, as well as 4 varieties of Nitella, have been found in the south of the West Siberian Plain. There are also less common species, which may also have competitive advantages for their development over other vegetation. At the same time, charinous algae are not limited to water bodies and marshy areas. Representatives of the genus Nitella, for example, are found only in the valleys of large rivers and forest steppes. And this despite the fact that in general the variety of char plants in such places is noticeably lower in comparison with the same water bodies.
Structure
Kharovy has one of the most complex structures of the thallus, which in some way determined their similarity with higher plants. Their body differentiates into internodes and full nodes, in which whorls of branches are located. In slightly salted and fresh lakes, they attach to the ground by means of rhizoids. As for the common features with higher vegetation, hornwort and horsetail can be mentioned in this context. In height, the thallus reaches an average of 30 cm, although specimens of 120 cm are also found. The lateral branches are very limited, so the plant populates the bottom is not very dense. But this is not all the features possessed by char algae. The structure of the internodes is characterized by the presence of a long cell, overgrown with a cortex of other narrow and small cells. It is noteworthy that the membrane of such cells is calcified.
Algae propagation
The char group of plants is characterized by sexual and vegetative reproduction. The vegetative method is implemented using nodules located on rhizoids. In addition, star-shaped cell accumulations located on the stem lower nodules are intended for this function. It is they who give life to the new tall. The genital organs, represented by oogonium and anteridium, reach the highest development during the life of the plant. These are multicellular structures that often develop on the same plant. However, dioecious char algae are also known, but their distribution is not so great. Due to its unpretentiousness to the living conditions, the Haras can cover huge areas in just a few years, forming continuous thickets.
Reproductive organs
Anteridium outwardly resembles a ball, the diameter of which can be 0.5 mm. Initially, it has a greenish tint, but in the process of life changes it to red or orange. It is located on a unicellular short stalk and contains 8 flat cells in the structure, which are closely in contact with the edges with notches. A unique cylindrical handle, ending in a round head, on which several more cells with a smaller fraction are placed, is sent from the central part of each cage-cell to the anteridium. Each of them gives several hundred cells with the help of spermatogenic threads. In turn, each of the newly formed cells also creates an anterozoid. As for oogonium, it is quite large, when compared with anteridia. Crust cells encircle it with a spiral and form a kind of crown. In this organ, charinous algae contain one large egg. The sperm passes to the cells of the corona and is screwed into the oogonium. Further, by means of karyogamy, the formation of a zygote occurs.
Functions of char plants
In the biosystem, the vital activity of these algae is insignificant, although experts note some influence on the hydrological background and biological qualities of the reservoirs in which they live. In particular, the water regime becomes more stable and a special biocenosis also forms in it. Plant thalli in the process of development acquire a large number of epiphytes. These are microscopic bacteria and algae that serve as food for invertebrates. In addition, dense kharovy algae can act in some way as a haven for small fish that find protection against predators in thickets. In reservoirs with dense development of such vegetation, more small mosquito larvae are observed. This is due not only to providing protection, but also to the action of special antibiotics that secrete plants. At the same time, algae can become food for birds. This is observed during periods of autumn overflights. Waterfowl mainly use zygotic oospores, which at this time are filled with drops of fat.
Application in economy and science
The nature of the use of plants in human life is determined by the substances contained in it. For example, the presence of lime makes algae attractive for use as a fertilizer. In particular, the Charophyta Charova algae department is useful in terms of feeding heavy soil strata. And even without additional processing, natural clusters with char deposits form healing mud. In recent years, interest in this group of plants has been shown by specialists in the field of biophysical research. The large cells that form the internodes provide an opportunity for a deeper study of the cytoplasmic membranes for their permeability.
Conclusion
Charova gradually lose their position in the plant hierarchy. Despite the resistance of some types of these algae to external influences, the spread of pollution in hydrological resources still inhibits their development processes. Also, do not forget that char algae is a group of lower algae, which is a transitional link between different departments. And although scientists today confidently systematize this group, many signs of its representatives indicate evolutionary changes in the same thallus. On the other hand, experts acknowledge that, compared with ancient fossils, modern charovy are not as rich in variety.