The top layer of soil, densely overgrown with herbaceous plants, is the basis of fertility

The top layer of soil, densely overgrown with herbaceous plants, is called turf in soil science. The prosperity of the country depends on the fertility of this horizon. It's not for nothing that Franklin Delano Roosevelt (thirty-second US president) said that the people destroying the soil ultimately destroy themselves.

The process of soil formation: why is fertility everywhere different?

Several stages are typical for the formation of soils on the globe. Initially, the rocks were destroyed under the influence of temperature, wind, water. Small pieces formed rustle - this is the primary minerals (quartz, feldspar , etc.). He gave the opportunity to settle organic.

The first settlers were mosses, lichens, microorganisms. Their life activity changed the layer itself, it became already suitable for the existence in it of higher plants. The next stage was already dependent on the climate: the more favorable the conditions (higher temperature, less moisture, absence of prolonged frosts), the easier and faster the further process took place. That is, in the southern regions soils are formed faster than in the northern. On the soil-forming process affects the terrain - slopes can not absorb moisture completely, the water runs down, it stagnates: on the slopes and in the lowlands of the soil are different.

Summarizing, we can say that the soil cover of different localities differ in mechanical composition - from sand to clay, chemical - from sod to podzolic, water regime - from normal-natural to excess. In pure form, soils are very rare, forming various subtypes under the influence of a variety of natural factors.

What is the name of the topsoil?

The soil profile (vertical section) has several layers called horizons. The upper fertile soil layer (horizon) is called humus, the next is the transitional layer, the latter is the soil-forming one.

The future of the planet depends on the thickness and composition (fertility) of the humus horizon. The unreasonable influence of man has a detrimental effect on the state of the soil - improper possession of soil cultivation methods for obtaining ultra-high yields destroys the humus layer, and its erosion occurs. Deforestation and frequent fires change the green appearance of the planet. The wind and precipitation complete the destruction.

Above the fertility of soils live microorganisms. The environment of their life is: plant remains (grass, hay, fallen leaves, branches, mushrooms), animal remains (worms, insects, bacteria, microorganisms). Organics and chemical compounds, called humus, form the humus horizon. The microflora and the microfauna, working on the formation and restoration of fertile soils, are called microbiocenosis.

Layers of fertile soil

Mulch is the first layer of fertile soil.

This layer is under our feet - plant and animal remains. Under their layer live beetles, a variety of worms, flies, fleas. Their number can reach several tons per hectare. All this a huge number of small creatures leads a fairly active lifestyle: they move, eat, multiply, cope with their natural needs, die, after all. Their remains are decomposed to the primary state. The top layer of soil, densely overgrown with herbaceous plants, develops only under favorable conditions.

Biohumus is the second layer of fertile soil.

It consists of the waste products of microflora and microfauna of the first layer, the remains of themselves, plant remains. In some places, its thickness is significant - up to 20 centimeters. Biohumus serves as a medium through which plants not only receive adequate nutrition, but also preserve (develop) their immunity.

The ridiculous deep plowing (perekopka) destroys the layer of biohumus, and the seeds sown after this process give a frail plant.

Biomineral (third) layer of fertile soil.

The top layer of soil, densely overgrown with herbaceous plants, a layer of mulch protects the soil from drying on one side, on the other - allows moisture to penetrate deep inside. At the same time, the decomposed remains of plants along with biohumus are also transferred into the depths. Biochemical reactions occurring in this layer, accumulate biomineral fertilizers for plant growth. The roots of plants, penetrating deeply into the soil (almost as deep as the height of plants), from this layer are fully nourished.

The fourth layer of fertile soil is humus.

It operates microorganisms in conditions of limited access to air and moisture, creating unique hydrocarbon compounds, carbon dioxide, methane and combustible biogas. This process is called biosynthesis, it is he who creates bio-nitrogen accumulations. This layer on one side warms the plants, and on the other - plants, as well as microflora and microfauna, absorb the evolved carbon dioxide and methane. Thus, soil bio-nitrogen accumulations are formed.

Subsoil, clay - the fifth layer of fertile soil

It regulates moisture exchange and gas exchange at a depth of more than 20 cm.

Classification of Russian soils according to VV Dokuchaev

Vasily Dokuchaev (1846-1903), a geologist and soil scientist, created a classification of Russian soils. Among the soils in composition, he distinguished the following: clayey, sandy, loamy, peaty, calcareous, turfy, sandy loamy.

Clayey

It is fertile, rich in nutrients, but difficult to process soil. After drying, they become very dense. To improve their structure, it is necessary to annually carry out a set of agrotechnical measures: digging, applying deciduous land, manure, ash and peat.

Sandy

These are loose, easily flowing soil. They are depleted in potassium and magnesium, they require the introduction of litter, mineral fertilizers (small doses) and sod land. Only in this case it is possible to get overgrown with grass the top layer of soil.

Loamy

These soils are very fertile: they are breathable on the one hand, and on the other hand they retain moisture well. But if they are very often dug from above formed a dense crust, preventing the entry of moisture.

Peat

In these soils, catastrophically lacking calcium and potassium, little phosphorus. But if you add sand, lime and mineral fertilizers - after a while the soil will become monotonous and very fertile.

Calcareous

There are many such soils in Russia. In their composition - half lime, the rest is clay or sand. The roots of plants in this case receive little water, it is retained by the crust on the surface.

Soddy

The top layer of soil, densely overgrown with herbaceous plants, is the definition of the turf. Such soils were formed in extensive open areas from St. Petersburg to Kaliningrad and Kamchatka. Moisture and abundance of meadow grasses created a special microclimate in the fertile layer, which enriches planted plants with minerals and organic substances as well as chernozem. These soils have long been used as hayfields and pastures.

Sandy loam

These lands easily absorb moisture without forming a crust. They heat up very quickly. Agrotechnical methods for them - the introduction of peat, compost and manure.

Modern classification of soils

Since the 1950s, a new systematization of soils has been established, taking into account diagnostic indices for taking into account soil formation regimes and modern environmental conditions.

The newest classification was published in 2000. It is called profile-genetic and takes into account the structure of the soil profile and its properties.