Algae are a very large and heterogeneous group of lower plants. In addition, they are the most numerous photosynthetic organisms on the planet, which are very important for our nature. You can meet algae everywhere. These organisms live in the oceans, fresh water bodies and seas, as well as on tree bark and moist soil.
Classification
To date, science has systematized more than one hundred thousand different types of algae. They, in turn, are divided into ten groups depending on the nature of the color:
- blue-green;
- golden;
- pyrophytic;
- yellow-green;
- diatoms;
- brown;
- red;
- green;
- euglenic;
- char.
Importance in Biogeocenoses
Algae in the aquatic environment are the main producers of organic substances. They not only directly, but also indirectly serve as the main source of nutrition for all animal bodies of water. Some rocks are known (oil shales, diatomites and limestones) that appeared in past geological stages as a result of the life cycle of these photosynthetic organisms.
Role in nature
Marine plants are indispensable for life on our planet. First of all, the importance of algae in nature is due to the fact that they are food for many organisms. These plants feed on crustaceans and mollusks, sea urchins, fish, etc.
Algae are of great importance in nature and as a source of oxygen formation. They account for thirty to fifty percent of this valuable substance, which is secreted by the plant world of our planet.
Algae, as well as terrestrial flora, relieve the atmosphere of the problem of excess carbon dioxide. Sometimes there are so many of them that water takes on a variety of colors.
Algae perfectly adapt to a variety of conditions. These plants can live in rainwater, where the amount of salt is minimal. Rocky hot surfaces and ponds of high mountain glaciers become their habitat. Algae can also be found in the upper soil layers, where sunlight hardly penetrates. These plants are able to populate lifeless rocky and soil substrates. The importance of algae in the nature of such zones is extremely high. These unique plants create the conditions for fertile soils.
The importance of algae in nature is great for the circulation of substances. First of all, they eat crustaceans, which are later eaten by fish.
Red algae
Almost all representatives of these plants live in the seas. Red algae have a considerable length, which can reach two meters. In addition to chlorophyll, representatives of these species of marine plants contain a variety of pigments in their cells. Their color also affects the color of the algae themselves. As a rule, the pigments of such algae are red. However, pink, bluish and other colors are possible.
Red algae, which is also called scarlet, have a fragile and delicate body. The color of these plants, from bright red to almost black, gives the underwater kingdom incomparable beauty.
Practical use
The value of red algae for humans is very high. One of the varieties of these plants - chondrus, which lives in the North Sea - is used as a medicine to cure respiratory diseases. From red algae, agar-agar is used, which is used in the confectionery business. Crimson trees are also necessary for microbiologists. In laboratory conditions, they are used to obtain pure microbial cultures .
Brown algae
This type of underwater plant for coastal areas is one of the most important sources of organic matter. This is especially true for the seas of the circumpolar and temperate zones. In these areas, the biomass of algae per square meter can reach several tens of kilograms.
Real thickets form brown algae. The significance of these “marine forests” is very great. They are not only a shelter, but also a place of feeding and breeding of many coastal animals. In addition, brown algae creates excellent conditions for other micro- and macroscopic algae to propagate in the zone of their distribution.
Amazing plants are the world's only source of production of alginic acid salts - alginates. This substance is able to absorb up to three hundred weight units of liquid, as a result of which a viscous solution will be obtained. This ability allows the use of brown algae in the food industry. The alginates obtained from them are added to ice cream, canned food and fruit juices. In addition, this substance increases the quality of books when printing, and also serves to impart color fastness to dyed fabrics.
Alginates made from brown algae are needed in the production of synthetic fibers and plastics. They give building materials and coatings weather resistance. Alginates are also used as raw materials in the production of high-quality lubricants for machines, soluble surgical threads, pastes and ointments in the perfumery and pharmaceutical industries. Brown algae have long been eaten. They are especially revered in the cooking of the peoples of Asian countries.
Green algae
This species of aquatic plants is widespread throughout our planet. Most green algae are found in fresh water bodies, but there are a considerable number of their marine forms. There are species of these plants that have adapted to terrestrial habitat and to life in the soil layers. You can meet green algae on the rocks, on the bark of trees, as well as on various buildings. Vast areas of development of these plants contribute to the "flowering" of water, snow, soil, and tree bark.
Great value green algae in nature. First of all, it is a source of oxygen. An important role of these plants in the cleaning of reservoirs. The importance of green algae is difficult to overestimate. They process carbon dioxide and nutrients that are dissolved in water, and also take part in the synthesis of organic substances.
Currently, various nutrient products are obtained from these representatives of aquatic life. They are also used for medical purposes. A special substance is isolated from green algae - chlorellin, which inhibits the spread of a number of pathogenic bacteria in the body. These plants and traditional medicine did not ignore. Filamentous green algae are used in painkillers.