How humus is formed: what is included in the composition and how the process occurs, in which soils it is more

Humus is an integral component of soils, the main characteristic of the fertility of agricultural land. Its content determines how suitable the soil can be for growing plants. Consider what humus is, how it is formed, how it differs from humus, and the classification of soils according to their humus content. How the substance is used in agriculture.

What is humus and how is it formed

Humus is the most important organic soil substance, which contains the nutrients used by plants. In the composition of the upper horizon, the volume of humus is different, most of the humus is part of the chernozems.

Soil matter is formed from organic substances and their derivatives and organomineral compounds. The process of its formation is called humification, the finished substance is formed from organic material - rotted plant residues.

Organics are processed by soil microorganisms and animals. First, plant residues are processed by earthworms. Then the semi-processed organic matter is consumed by the soil microflora, continuing to process it. Aerobic and anaerobic bacteria take part in this process. They break down organic material into simple compounds. The earth is filled with minerals.

There is a direct relationship between the number of soil inhabitants and the rate of creation of the humus layer. The more of them, the faster the humus is formed. Earthworms not only digest organic residues, but also loosen the earth, making a lot of moves in it.

Thanks to humic substances in plants, the growth of all parts of the body is activated; carbon dioxide, which is formed during the decomposition of organic matter by anaerobic bacteria, is used by plants in the processes of respiration. Humus is a good baking powder, it makes even dense loamy soil looser and softer. At the same time, it strengthens the earth, makes it more structured, and reduces erosion.

Substances in its composition bind toxic components, deactivate them, limiting their spread. During the processing of organic matter in the humus layer, the main and additional nutrients are released and accumulated.

Differences from humus

The difference is that humus is formed from humus in the upper soil layer over many years. Humus is obtained from plant residues and animal manure.This is a homogeneous loose mass, light, reminiscent of black earth in color, it can be black or brown. Good humus smells like spring earth, contains a large amount of nutrients and organic matter.

You can also get humus artificially - put leaves, grass, twigs, manure into a compost heap, mix and leave to rot. Fresh humus is obtained at least a year after laying the materials, mature humus is considered if it has been lying for 2-3 years. After being applied to the soil, humus is obtained from it after further processing by bacteria.

Classification of soils by humus content

Classification is based on the content of this important soil component. The volume of humus is expressed as a percentage. Consider how much humus is contained in soils using the example of different types of chernozem.

Low humus

In such soils, the content of fertile matter varies between 2-4%.As a result, the soil gets a gray or dark gray color. The fertility of such soils is the lowest of those considered, there is little humus in them, moisture and air penetrate worse, the speed of microorganisms is reduced.

Moderately humus

Contain 4-6% humus in the soil layer. Such soils have higher fertility than the previous type, they are darker, have better characteristics.

Medium humus

Under the influence of bacteria, 6-9% of the substance accumulates in the soil layer. Such soils are more structured, have good moisture and air permeability.

Humous

The humus layer has the highest content of matter - from 9% and above. These are the most fertile and economically valuable lands. They are black in color, warm up well, and plant nutrients are perfectly fixed in them.

Where is it used?

Humus, as a constituent of the soil, is used for growing plants, in agriculture, and on private plots. It depends on him to a greater extent what yield can be obtained with standard methods of agricultural technology.

With the constant use of the soil, the humus content gradually decreases, so it needs to be restored. Restoration of fertility is achieved by adding humus, laying mulch and fertilizing. Such measures are necessary, since plants draw out a lot of nutrients, but the fruits that are collected from the ground do not return to it, new humus is not formed from them.

In order for the humus substance to form faster, it is necessary to apply other agrotechnical measures when growing plants - loosening, which makes the soil softer and allows air to penetrate to the roots and be used by microorganisms for their work.

In order for bacteria - the main converters of organic matter - to multiply, it is necessary to apply not mineral, but organic fertilizers and limit the use of pesticides, especially synthetic ones, which negatively affect the microflora when they enter the soil.

Humus is formed in the soil constantly, it is a natural process. How fast it goes depends on the climate, vegetation and the activity of soil microorganisms. Chernozems are considered the most humus, but even in them the humus content is uneven. Other types of soils are inferior to chernozems in fertility, but remain fertile enough for agricultural use.

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