Soil microflora: composition and methods of its research, management features

Soil is a waste product of the organisms that inhabit it. They affect the process of its formation, self-purification and circulation of useful elements. Soil microflora determines its qualitative composition and the possibility of using it for agricultural purposes. Today, many different methods have been developed for studying the composition of the soil and managing it.

Species and quantitative composition

There are quite a lot of varieties of bacteria in the soil, which are divided according to their functions, habitat, nutritional habits and other parameters.In the earth there are decay bacteria, parasites, symbionts. At the same time, the relationships between different types of microorganisms differ significantly.

Single-celled organisms that form spores have 12 varieties. They are divided according to the criterion of preferences for the environment. For example, only high temperature parameters are suitable for thermophiles. Under the influence of unicellular, many substances are transformed into elements that are characteristic of plant development.

Contamination of soil with feces leads to the appearance of pathogenic flora. These microorganisms can penetrate the soil from plants or the intestines of animals. This provokes the development of decay processes. The main representatives of pathogenic bacteria are coliform prokaryotes. These single-celled microorganisms can live in the soil for a long time, provided it is well heated and not exposed to direct sunlight.

Coliform bacteria are considered the most dangerous. They penetrate the soil from the intestines of animals. Also, microorganisms that produce toxic enzymes are of great danger.

According to the shape of cell walls

The division of microorganisms depending on the shape of the cell walls is based on the results of genomic studies. This principle allows us to distinguish several types of unicellular:

• cocci - have cells in the form of spheres;
• bacilli - their cells differ in the shape of the rod;
• spirilla - these microorganisms have a spiral shape.

There are also soil organisms that have a complex structure. This group includes actinomycetes, which have many branches.

In relation to oxygen

Depending on the ways in which oxygen is used for life, the following types of bacteria are distinguished:

• aerobic - they require oxygen to exist;
• anaerobic - die if oxygen is present in some layer of soil.

According to the ability to be stained by the Gram method

The essence of this method lies in the presence of an outer shell, which has protective functions. It is able to pass or, conversely, interfere with the entry of the antibacterial component and the coloring matter into the structure of the bacteria.

Gram-positive bacteria are large varieties that are thick-walled and tolerate water stress. Gram-negative are small organisms that do not have resistance to water stress.

In most cases, Gram-negative organisms are found in soil:

• pseudomonas are small solitary bacteria that do not cause spores;
• budding bacteria - this group includes nitrifying organisms;
• nodule unicellular;
• enterobacteria - are mobile and immobile and are considered pathogenic for plants;
• azotobacteria - are large mobile free-living rods;
• myxobacteria and cytophages - these microorganisms produce mucus and strands with a dense structure.

Gram-positive bacteria include the following varieties:

• spore-forming;
• bacilli - these are rod-shaped bacteria that live in colonies and are highly mobile;
• large anaerobic organisms that take part in the processes of decay, fermentation of pectin, carbohydrates, starch;
• coryne-like bacteria - live in bedding, soil, plant substrate.

By food type

Depending on the type of nutrition, bacterial microorganisms that live in the soil are autotrophic and heterotrophic. The first group extracts organic matter for life on their own, the second uses ready-made organic matter.

By function

Organisms that are present in the soil are required for the destruction of organic matter. During the implementation of vital activity, unicellular saturate the soil with important elements. Nodule bacteria are responsible for nitrogen fixation near the roots. Nitrifying microorganisms are required to improve soil fertility.

Also, depending on the functions, there are such categories of unicellular:

1. Destructors - digest carbohydrates and various substances presented in the form of living or dead organic matter.
2. Mutualists - such bacteria cohabit on favorable terms. An example is nodule bacteria.
3. Chemoautotrophs - get energy from inorganic elements without carbon content.

All these categories of soil microorganisms are very important for the nutrition of flora representatives. Unicellular help transform soil organic matter, neutralize pesticides, prevent plant pathologies, and provoke the accumulation of nitrogen in the soil. Microorganisms also form soil aggregates, which contribute to an increase in moisture capacity.

How to study soil microflora

The soil is examined through a full or brief analysis. Full control is carried out in such situations:

• detailed and in-depth characterization of the sanitary condition of the soil;
• assessment of soil suitability for various buildings;
• epidemiological studies.

Short study required for current he alth control. It helps to determine the total number of saprophytic and thermophilic bacteria, clostridia and other organisms.

Complete sanitary-bacteriological analysis additionally includes an assessment of the number of fungi, actinomycetes, shigella, salmonella. In addition, it helps to identify and quantify the pathogens of botulism, tetanus, brucellosis, anthrax.

Control Features

To neutralize the soil, which is contaminated with harmful microorganisms, mechanical processing is carried out and various plants are planted. The use of chemicals provokes a decrease in soil fertility.

To normalize the soil microflora, it is permissible to use various biological fertilizers. With their help, it is possible to saturate the soil with valuable substances, reduce the activity of pathogenic bacteria, and make the substrate more fertile.

Thanks to this, the substances significantly increase the yield parameters of cultivated plants and help to cope with the influence of adverse factors. In addition, they significantly reduce the number of nitrates and heavy elements in the soil structure.

Soil microflora is an important indicator that is often used in agriculture. The composition of the soil contains many pathogenic and beneficial microorganisms that affect the development of cultivated plants.

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