Chemical composition of the soil: briefly about the main elements, why they prevail

Soil is a constant source of nutrition for all plants that draw out the mineral elements in it by roots. Consider the chemical composition of the soil, the nutritional value of arable land, the gross content of elements. The percentage and value of nitrogen, phosphorus and potassium for crops, the content and effect on plant growth of microelements.

Chemical composition of soils

The presence of chemical elements contained in the soil is influenced by the composition of the geospheres that took and take part in its formation: lithosphere, hydrosphere, atmosphere and biosphere.

Almost all chemical elements can be found in the soil, but most of them are in small quantities. Only 15 are of great importance: C, N, O and H, which create organic matter, non-metals S, P, Si and Cl and metals Na, K, Ca, Mg, AI, Fe and Mn. The quantitative content of elements is different: oxygen and silicon predominate, followed by aluminum and iron, calcium, sodium, magnesium and potassium. They occupy 99% of the mineral volume of the soil, all the rest - 1%. The soil contains 20 times more carbon and 10 times more nitrogen than the lithosphere, which is due to the activity of soil bacteria.

All elements, except for nitrogen and oxygen, make up the ash part of organic matter, which is formed from chemical constituents concentrated in the soil. The life of vegetation depends on the presence and quantity of available forms of elements in the earth. They assimilate, for the most part, N, P, K, S, Ca, Mg, Fe, Na, Si, therefore they are called macronutrients; B, Mn, Mo, Cu, Zn, Co, F, consumed in a smaller volume - microelements.Of these, N, P, S, Fe, Mg are involved in the construction of proteins, K, Cu, Mn, Na - regulate the functioning of cells and serve to form various plant tissues.

Arable land

The chemical composition of agricultural land depends on the type of soil, mechanical composition. The main elements form different mobility and compounds, which determine the ability to migrate, the availability of plants and the acidity of the soil. Compounds differ in structure, composition, resistance to weathering, solubility. In soils, they can be contained in the following forms: primary and secondary minerals, organomineral compounds, organic, absorbed forms, soil solutions and its gaseous part, living matter (bacteria, algae, fungi, microfauna).

Plants and soil microorganisms consume elements dissolved in the soil solution, are in an exchange state and are part of rapidly dissolving organic matter.

Gross element content

The gross content of elements in the mineral part of the soil is defined as the content of oxides, expressed as a percentage. This indicator gives an idea of what elements the soil consists of, which ones predominate in it, how they are distributed along the profile. According to the gross content, it is possible to establish the origin of the soil, the processes that formed the horizons, and predict the level of fertility of such soil.

In soils of almost all types, silicon oxides are the main component, they occupy 60-70%. Aluminum occupies, on average, 15-20%, iron content varies from 0.5-1% to 20-50%. Oxides of potassium, magnesium, calcium and sodium occupy 5-6%, the oxides of other elements together are included in 1%.

Nitrogen content

Located in humus, part of organomineral substances, it is the main component of plant nutrition.Nitrogen is bound in the soil with organic matter and is available to the roots in ammonium, nitrate and nitrite forms. Stimulates the growth of green parts, most important in the early stages of plant development.

Phosphorus in soils

Included in the organic matter of the soil, contained in it in the form of s alts of phosphoric acid in combination with iron, aluminum and calcium. From organic matter, phosphorus passes into a form accessible to plants in the process of mineralization after the processing of organic residues by microorganisms. Phosphorus is essential for plants and, above all, for the normal development of roots and the improvement of fruit quality.

Details about potassium

The third main nutrient included in the composition of primary and secondary minerals, therefore it is inaccessible for crops. In the soil solution, potassium is in the form of simple s alts, on the surface of colloids - in the exchange state.From the soil solution, potassium easily enters the plant cells through the roots. Potassium like vegetables, root vegetables, potatoes, tobacco, cultivated herbs.

Micronutrients

Found in soil in small quantities, but they are just as important for normal plant growth and development. Their number is determined by how much is in the breed. Trace elements are found in humus, in the composition of primary and secondary minerals.

Chemical composition is an important indicator by which you can determine the level of soil fertility. In order for it to give a good harvest, a sufficient presence of all the elements necessary for plants is necessary. During the season, it is recommended to control the number of elements and apply fertilizer to replenish their volume.

20 mineral elements are considered necessary for plants, each of them is responsible for the physiological processes occurring in plants, and becomes a building material for their tissues.If any element is missing, plants develop worse and slow down growth, get sick more often, do not tolerate cold and heat, and sharply reduce yields. The same is observed with an overabundance of nutrients. The content of elements should be balanced, fertilizers should not be neglected, as well as exceeding the recommended dosage, so as not to cause overfeeding of plants.

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