Different Types Of Soil
In our planet there are many types of ecosystems whose intrinsic characteristics depend on the type of soil, the climate, the environmental conditions of each moment, etc. The type of soil that we see in each part of the world depends on five factors forming the soil : climate, bedrock, elevation, weather and the organisms that live in it.
In this post we will see the different types of soil that exist and the characteristics of each one. Do you want to know about the types of soils that exist? The discipline that study the different types of soils is called pedology.
Definition and components of the soil
The soil is the superficial part of the earth’s crust, biologically active, that comes from the disintegration or physical and chemical alteration of the rocks and the residues of the activities of living beings that settle on it.
As mentioned before, in each area of the world there is a different type of soil . This happens because the soil forming factors change throughout space. For example, the climate is not the same on the entire planet, neither is the relief, nor the organisms that live in it, etc. Therefore, soils change their structures slowly and gradually as we move through different ecosystems.
The soil is made up of several components such as rocks, sand, clay, humus (organic matter in decomposition), minerals and other elements in different proportions. We can classify the soil components in:
- Inorganic , such as sand, clay, water and air; Y
- Organic , like the remains of plants and animals.
Humus is all decomposing organic material that gives fertility to soils. From leaves drying, to corpses of insects, they are part of the soil humus. This is found in the upper layers and, together with some minerals, it turns a yellowish black color, conferring a high degree of fertility.
Characteristics of the soil
Soils are differentiated by their physical, chemical and biological properties.
- The texture determines the proportion in which the mineral particles of different sizes that are present in the soil are found.
- The structure is the way in which soil particles come together to form aggregates.
- The density influences the distribution of vegetation. Heavier soils are able to sustain more vegetation.
- Temperature also influences the distribution of vegetation, especially in altitude.
- The color depends on its components and varies with the amount of moisture present in the soil.
- Exchange capacity: This is the ability of the soil to exchange clay and humus, yielding nutrients to the plants through the capture of mineral particles.
- Fertility : It is the amount of nutrients that are available for plants.
- pH: the acidity, neutrality or alkalinity of the soil. Then later we will see how to change the pH levels of a soil.
Here we find the species of organisms that live in it, animals, bacteria, fungi , etc. Animals also exercise their function in the soil, depending on their diet, activity, size, etc.
Types of soil
The type of rock through which the soil originated, the topographic characteristics of the area, climate, weather and living organisms that inhabit it are the five main factors that determine the types of soils.
Based on these soil-forming factors, we have these types of soil distributed throughout the world:
Sandy soils are formed, as the name suggests, mostly by sand . This type of structure, given its high porosity and its low aggregation, does not retain water, making its amount of organic matter low. Therefore, this soil is poor and not suitable for planting in it.
These soils have a large quantity of calcareous salts. They are usually white, dry and arid. The type of rock that abounds in these soils is limestone. Being so hard does not allow agriculture, since plants can not absorb nutrients well.
These soils are also called black earth because, being rich in decaying organic matter, this dyes the soil black. It is dark in color, retains a large amount of water and is excellent for agriculture.
These are formed mostly of clay, fine grains and yellowish. This type of soil retains water forming puddles, and if mixed with humus it can be suitable for agriculture.
As the name suggests, they are full of rocks and stones of all sizes. By not having sufficient porosity or permeability does not retain water well. Therefore, it is not suitable for agriculture.
They are those soils that have intermediate characteristics between sandy soils and clay soils, that is, of the two types.
How to change the pH to a soil
There are times when our soil is too acidic or alkaline and can not sustain well the vegetation and / or crops that we want to plant.
When we want to change the pH of the alkaline soil to make it a little more acidic, we can use the following:
- Sulfur powder: the effect is slow (6 to 8 months), but being very economical is what is most often used. We have to contribute from 150 to 250g / m2 and mix with the earth, and measure at pH from time to time.
- Iron sulfate: it has a faster effect than sulfur, but it is necessary to measure the pH since we could lower it more than necessary. The dose to lower 1 degree the pH is 4 grams of sulfated iron per liter of water.
- Blonde peat: it has a very acidic pH (of 3.5). We have to throw 10,000-30,000kg / ha.
On the other hand, if we want to change the pH of an acid soil to make it more alkaline, we should use:
- Ground limestone : we have to extend it and mix it with the earth.
- Calcareous water: highly recommended to raise the pH only from small corners.
In either case we have to measure the pH, since if we are growing acid plants (Japanese maples, camellias, etc.) and raise the pH to more than 6, they will soon show symptoms of chlorosis due to lack of iron, example.
Importance of soil
Soils have great importance throughout the world and are also being degraded by the continuous pressure exerted by the human being on him. It supports crops from around the world, plantations, forests and is the basis of all terrestrial ecosystems.
In addition, it intervenes in the water cycle and the cycles of the elements. In the soils there is a great part of the transformations of the energy and the matter of the ecosystems. It is the place where plants grow and animals move.
The urbanization of cities makes them lose land and the continuous forest fires and pollution increasingly degrade them. Since the regeneration of soils is very slow, it must be considered a non-renewable resource and increasingly scarce.
Man obtains from the soil not only most of the food, but also fiber, wood and other raw materials.
Finally, they serve, because of the abundance of vegetation, to soften the climate and favor the existence of water currents.
For all this and for more reasons, it is of vital importance to learn to value the soil and to conserve it.