Plants consume air not only from the atmosphere, but also from the soil using their roots. Of course, the soil does not contain many gaseous components, however, the yield of a certain area or a large area of agricultural land largely depends on the correct air and water regime of the soil. Academician Vernadsky emphasized the significant role of gases in soil processes.
What does soil with a lot of air look like and what is its composition?
The soil, which contains a large amount of air, is loose, flowable, has fairly large particles, allows water to pass through well, but retains a certain amount of it. This soil is rich in nutrients and well aerated.
For the development of agricultural plants, loamy soil is considered the best soil option. It is suitable for growing dozens of crops and has the following characteristics:
- Ease of processing.
- High percentage of nutritional components.
- Significant level of air and water permeability.
- Uniform distribution of moisture along the horizon.
- Retention of thermal energy.
This type of soil does not need improvement; its quality can simply be maintained by applying organic and mineral fertilizers, digging and mulching.
For potted plants, the substrate is specially made, taking into account the specific requirements of different species. Most of them prefer light, permeable soil with good water retention, in which air forms a part reaching 25% of the total volume, water - 25%, mineral components - 25%, and organic matter - only 5%.
The best characteristics in terms of soil gas content are soil consisting of chernozem, sand, and weathered (non-acidic) peat. To give greater air and water permeability, inert natural components, such as perlite, or those of artificial origin (foam balls) are added to such soil. Such soil has the highest characteristics in all important parameters: nutritional value, breathability, moisture retention and transmission. The roots of plants develop well in it, and the green mass grows regularly
Ecological role of soil air for plants
For plants, not only atmospheric air is important, but also its presence, quality and composition in the soil. Soil gases fill all the voids in the ground that do not contain water. Plants develop best if air is contained in large voids and water in small and medium ones.
Gas exchange occurs continuously between soil and atmospheric air. Loose soils exchange gaseous components better and faster than dense or swampy soils, because in the former there are practically no pores, and in the latter, air from the cavities is displaced by excess water.
There is less oxygen in the soil than in the atmosphere, but more carbon dioxide. This leads to the process of diffusion, that is, mixing and redistribution of gases. Such soil properties have a positive effect on the development of plants that require an abundance of carbon dioxide to absorb nutrients. At the same time, plant roots need less carbon dioxide than the above-ground part, so continuous air exchange is the most important condition for obtaining healthy plantings and full-fledged harvests.
Conditions for gas exchange between soil and atmosphere
In order for the soil and atmosphere to carry out full gas exchange, the soil must meet the following indicators:
- Air permeability, that is, the ability to let air through.
- Air capacity is the volume occupied by air in the soil at specific moisture levels.
Loose soils are the most breathable and air-intensive because they have large cavities between individual particles. When organic substances, such as manure or compost, are added to such soils, the looseness and nutritional value increase, which leads to an increase in the most important indicators. Also, the addition of organic matter leads to an increase in the release of carbon dioxide, which stimulates gas exchange with the atmosphere, and this helps to activate the growth of the above-ground parts of agricultural and ornamental crops.
Ways of influencing the air regime of soils
The best ways to improve the air regime of the soil are loosening and applying organic fertilizers. This increases air permeability and leads to intense gas exchange between soil and atmospheric air.
For heavy, moisture-filled soils, planting cultivated plants on ridges or beds is used.
