Habitat factors have a major impact on all living organisms. All living things are constantly affected by both the organic components of the surrounding nature and inorganic. Each habitat differs in its own parameters - the state of aggregation, density, and the presence of oxygen. What environmental factor is called edaphic?
Definition
Edaphic factors include environmental conditions in which the plant grows. This is the presence and amount of water, gas, soil temperature. Also included is the chemical composition of the soil. Edaphic factors include the totality of the physical and chemical properties of the soil cover.
These factors are inferior in importance to climatic ones. However, they are important in the life of those organisms whose vital activity is directly related to the soil. Other properties that affect the life of various organisms are the physical structure of the soil (friability or density), slope, and particle size distribution. The specific features of the species and the movement of animals are also affected by the topography of the soil, and soil features.
Edaphic factor for plants and animals
Soil properties are important not only for plants and microorganisms living inside them. Even at the smallest depths underground, darkness reigns. This property is critical for those animal species that seek to avoid direct sunlight.
As the depth increases, temperature fluctuations in the soil become less critical. Daily changes quickly decay, and with even greater depth, seasonal changes in temperature also lose their significance. At a considerable depth, living conditions become as close as possible to anaerobic ones. Anaerobic bacteria live there. Earthworms also prefer living conditions, where the carbon dioxide content is higher than on the surface.
Vegetation and soil
Some types of ions contained in the soil are also of great importance. In this case, the edaphic factor completely characterizes the type of vegetation on the surface, determining which species will grow and which will not take root under these conditions. For example, those soils that are on the layers of limestone are very rich in CA 2+ ion . Specific types of vegetation called calcephitic (edelweiss, as well as some varieties of orchids) develop well on them. There are also types of plants called calcephobic. These are chestnut, heather, some types of fern.
Also, some types of soil are rich in ions of sodium (Na + ) and chlorine (Cl - ). Such regions are covered with unusual species of plants that stretch in the form of a ribbon along the entire sea coast - Salsola (hodgepodge), Salicornia (soleros), aster tripolium (tripolium). Environmentalists know that the seeds of these plants, called halophytes, can grow only in those types of soils that are rich in salts.
Soil composition
The chemical composition is one of the most important edaphic factors. The presence of certain chemical elements, as well as their quantity, is always a reflection of the geospheres that have influenced the formation of soil. In any soil are those substances that are common in the lithosphere, atmosphere, hydrosphere.
In the composition of any soil in varying amounts, you can always find almost all the elements of the periodic table. But the vast majority of them are still found in the soil in negligible quantities. In practice, environmentalists researching this edaphic factor deal with, at best, only a few - usually sodium, potassium, magnesium, manganese, aluminum, etc.
Soils also contain substances formed during the decomposition of living organisms. The greater the depth, the smaller the number of such substances. For example, in the forest, fallen leaves are an important source of certain substances entering the soil. Moreover, it is the deciduous litter in the forest that is richer in comparison with coniferous. It is used as food by the so-called destructive organisms - saprophytic plants, as well as animal saprophages. Saprophytes are usually fungi and bacteria, but plants are sometimes found among them - for example, some types of orchids.
Oxygen and Carbon Dioxide
Many experiments have also confirmed the fact that plant roots need oxygen in the soil. Their normal development is possible only in the presence of air. If there is not enough oxygen in the soil, then the plants begin to grow more slowly, and sometimes even die. Also, this edaphic factor is important for the existence of soil microorganisms. Their vital activity occurs only if there is oxygen in the ground. Otherwise, anaerobic conditions develop in the environment, which lead to acidification of the soil.
Thus, plants and microorganisms can suffer both from the presence of harmful chemical compounds in the soil, and from a lack of oxygen in it. In its composition, the air that the roots of plants feed on is poor in oxygen and rich in carbon dioxide. It also has water vapor, and in some places - for example, in swampy soils - there are also gases such as ammonia, hydrogen sulfide, methane, as well as phosphorous hydrogen. They are formed as a result of anaerobic processes that accompany the decomposition of dead organic tissues.
Water
No less important edaphic factor is the water content in the soil. First of all, it is important for plants. Salt compounds dissolve with water and become more accessible to plants. Drought adversely affects most plant types when the surface dries. This edaphic environmental factor is no less important for microorganisms, whose vital activity occurs only with sufficient moisture.
With a naked eye you can see how much the vegetation on dry soils and those that are rich in water are different. The fauna is also sensitive to this factor - animals, as a rule, cannot tolerate too dry soil. For example, earthworms and termites sometimes supply their colonies, breaking deep galleries underground. On the other hand, if too much water is contained, large numbers of larvae die.