The upper fertile layer of the earth, its characteristics

The earth is made up of a variety of components. What are the features of humus?


  • Features of the fertile layer of the earth
  • How is soil formed?
  • What is the difference between rich and poor soils?

Features of the fertile layer of the earth

The top fertile layer is called soil. If it is ignited in a tin container using a gas burner, an unpleasant aroma will begin to emerge. This happens because plant and animal residues that have rotted start to burn. It is they who give the top layer of the earth a characteristic shade.

If you start digging a hole anywhere, you can see that the soil layer has a difference in color from the soil that is under it. It doesn't matter what happens under the fertile layer, sand or clay, it will have a darker shade anyway. This is due to the fact that it contains humus. It is humus that is the necessary part of the earth that plants need.

How is soil formed?

The soil does not consist of humus alone. It includes the breed on which it was formed. There are such types of fertile soil layer:

  • Sandy
  • Clayey
  • Loamy, etc.

But how does the formation of soil occur? This can be understood with a specific example. For example, how does sandy soil form? Construction is planned on a specific site. People brought here a lot of river sand. After the completion of construction, part of it remains on the ground. Initially, nothing grows on it. But plants gradually appear, and their number increases annually. Before winter, the grass dries and decays. As a result, the soil is formed.

Video about the useful soil layer:

If you study this sand after 5 years, you will notice that the top layer already differs from the sand in color. Here larvae or bugs, plant roots have already appeared. Sandy soil forms on the sand. It is not rich, therefore only certain varieties of plants germinate here. But this is no longer sand, but poor soil.

After all, the sandy rock practically does not hold moisture, so the layer of such earth is dry. And in such conditions, only unpretentious plants grow. They do not grow large, so they produce a small amount of humus. It goes deep into the ground in a short period.

If someone was in a pine forest, they could have noticed that the pines grow practically on the sand. Every year they cover the ground with their needles, which gradually rot. The same reincarnation occurs with clay. The difference is that completely different plants will grow on such land. Clay soil is often formed on the slopes of roads.

In such conditions, weeds, coltsfoot and other plants that are able to develop on soil, where there is a small amount of air and moisture, grow well.

Over the years, a thin layer of soil appears on the clay. It consists of humus and sand that accidentally got into the territory. But it is much easier for plants to thrive in such conditions than on sand. Humus on sandy soil deepens under the ground, and it is washed away from clayey territories by melt water.

What is the difference between rich and poor soils?

If the fertile layer of the earth has just begun to form, or it contains little humus, then only certain vegetation will develop on it. These plants, in the course of their life, form a small amount of humus, so the emergence of soil is slow.

But not all soils are formed on clay or sandy soil. If this were the case, then humanity would not be able to get a good harvest. There are territories where black soil lies on the surface of the earth, which has a depth of even more than a meter. If you look at it, we can conclude that this is the soil, which is saturated with humus. A variety of plants can germinate under these conditions. But black soil is not of the same type. There are such varieties of it:

  • Dry
  • Light
  • Loose

Light viscous chernozem is especially appreciated. It turns to mud when a good rain has passed. All types of such soil are saturated with humus, so an excellent harvest can be grown in such territories. Fortunately, there is a lot of black soil on the territory of our country. This is rich soil. But I wonder how her education came about?

There is a lot of humus in the black soil. And it is formed from the decay of plants. Therefore, we can conclude that where the black earth is now, there was once a lot of vegetation. In addition, more humus is formed in the forest than in meadows. Every year, foliage and needles fall from the trees, which transforms into humus.

In addition, various herbs rot. But there are few forests that grow on black soil. Such soil was formed on the steppes and meadows. And now, in these territories, people make fields where they plant various garden crops. In the forest, the fertile layer of land is often poor. If you dig a hole, then the dark soil will be 10-20 cm, and then clay or sand begins.

If there is a shortage of water on fertile soil, then it will begin to dry out, no plants will grow on it, which will lead to its destruction. So, all over the planet, there is earth on land. But each territory is different. There is an upper fertile layer. It is he who allows the growth of various vegetation on earth.

Watch the video: This Diagram of Earth Is a Lie (January 2022).