What is soil? This word has more than one meaning. Most often it is found in the meaning of "fertile layer". Dictionaries and biological references approach the explanation of the term in more detail.
The soil, says the scientific definition, is the uppermost layer of the Earth’s lithosphere. Its main characteristics: fertility, heterogeneity, openness, four-phase.
Consider each concept separately.Fertility means that the soil is a layer suitable for growing crops and crops. The layer formed as a result of the vital activity of various organisms and weathering is rich in nutrients, and it is based on humus - living organic compounds or their residues that are present in the soil but absent in living organisms.
What is soil in terms of heterogeneity?This means that the fertile layer is a heterogeneous system, the homogeneous phases of which are separated from each other. So, the soil consists of four phases: solid, liquid, gaseous and microorganisms.
The solid phase includes minerals, organics, various inclusions, i.e. the entire set of solids that make up the fertile layer.
The liquid phase is water, which may be in the fertile layer in a free or bound state.
Gaseous consists of gases: oxygen coming from the atmosphere, complex compounds of nitrogen, methane, pure hydrogen. They are formed as a result of the processes of fermentation, respiration, decay, etc.
Исследуя почвы, ученые могут проанализировать не only the layer as a whole, but also each of its constituent phases. That is why the full answer to the question of what soil is is so long. In addition, the soil is sometimes considered as a barrier or membrane that simultaneously separates and organizes the interaction of the atmosphere, the bio- and hydrospheres.
Somewhat different answers to the question ofwhat is the soil, GOST 27593-88. It says that the soil is a natural body, an independent, organic-mineral, natural-historical, resulting from a combination of factors:
The soil, continues the definition of GOST, hasown properties (morphological and genetic). It is characterized by certain properties that are responsible for the creation of conditions for the development of plants, consists of water, air, mineral particles and organic remains.
The type and nature of the soil depends on climate, flora andfauna, origin, microorganisms inhabiting the fertile layer. The task of land use is to preserve and maintain fertility, adequately using the opportunities of the layer.
With too frequent use of soildepleted, with excessive fertilizer becomes almost poisonous. In the absence of moisture, the soil can become deserted, and if it is watered excessively, it can turn into ravines. Sometimes soils become salty or swampy as a result of improper use. These processes have a single name, namely, soil degradation.
Restoration of degraded soils is a very laborious, lengthy, not always successful process.
