The earth contains liquid, solid and gaseous components. The upper layer of the soil consists of plant and living residues decomposed under the action of microorganisms. It is called humus and occupies 10-20 centimeters. It is on it that flowers, trees, vegetables grow.
Under it is an infertile soil layer of 10-50 centimeters. Nutrients are washed out of it by acid and water, which is why it is called a leaching (leaching) horizon. Here, own elements are released due to chemical, biological, physical processes, clay minerals appear.
Deeper is the parent rock. It also has useful elements. For example, calcium, silicon, potassium, magnesium, phosphorus and others.
Let's take a closer look at humus, as it plays a very important role in our lives.
Humus: education, concept
Soil was formed during the weathering of rocks and consists of organic and inorganic components. In addition, it contains air and water. This isonly a scheme, but in fact each layer develops separately in accordance with certain conditions. Our earth only seems homogeneous, it is inhabited by worms, insects, bacteria.
The topsoil is its cover. In forests, it is represented by organic remains and fallen leaves, in open areas - by herbaceous vegetation. The cover protects the earth from drying, hail, cold. Under it, the remains of insects and animals decompose. In the process of this decomposition, the soil is enriched with mineral elements in a natural way.
Humus is inhabited by living organisms, penetrated by the roots of trees and plants, saturated with air. Its structure is loose, in the form of lumps. Here is the formation and accumulation of nutrients by root systems.
Anyone knows that the top layer of soil, or rather, humus, is very important for fertility. The black substance contains carbon and nitrogen. This is a kind of kitchen where food is prepared for planting (active humus). Also in this layer, a balance of nutrients, water and air regimes (stable humus) is created.
What affects the fertile soil layer
Tillage technology, type, climate, crop rotation affect the topsoil. In the garden, organic additions and well-rotted compost can significantly increase stable humus.
Soil type is important for gardening. It depends on the mineral composition. Vegetable plants grow well in neutral or slightly acidic soils.
There are indicatorsfertility:
- Total acidity.
- Actual acidity.
- Cation exchange.
- The need for liming.
- Saturation with bases.
- Grain size distribution.
- Organic content.
- Macronutrient content.
The indicator "soil density" also affects fertility. High values lead to deterioration of the air regime, difficult mobilization of nutrients, insufficient root growth. Low density delays the growth of the root system due to voids and leads to increased evaporation of moisture.
Currently, there are fertilizers and additives, as well as various procedures to improve the quality of the fertile layer. But the earth needs to rest. Remember this!
