Soil is a complex system of organic and inorganic matter that directly and indirectly supports plant and animal life. Consists of minerals, nutrients, water, microorganisms and biodegradable living matter, which provide the necessary elements to support growth. Soils of different geographical areas differ in chemical composition, structure, pH, texture and color. Soil forms the basis of the ecosystem and performs the functions necessary for the survival of living matter.
Development soil category
A number of systems have been developed to classify different types of soil. Some of them were specially formed in connection with the determination of soil suitability for use in specific engineering projects. Others are described more approximately and less accurately, although a certain degree of randomness is inherent in each of the systems.
Overview
The category of soil can be classified in terms of soil as a material and as a resource. Geotechnical engineers classify soil according to their functional properties. Modern engineering classification systems are designed to provide an easy transition from field observations to basic predictions of the properties and behavior of soil engineering.
There are three main classification groups:
- coarse-grained (for example, sand and gravel) - category 1 soil;
- fine-grained (e.g., silt and clay);
- highly organic (peat).
Other engineering systems classify soils in terms of their suitability for pavement construction.
A full description of category 4 geotechnical engineering soil will also include other properties (color, humidity, strength).
Main types
Soil categories are classified into soil, clay, silt, peaty, chalky and loamy soils based on dominant particle sizes.
Sandy soil is light, warm, dry. Sandy soils are also known as light soils due to the high proportion of sand and a small amount of clay. This compound has a fast drainage system and is easy to work with. They heat up faster in spring than clay soils, but in summer they dry out just as quickly and suffer from a lack of nutrients that are washed off by rain.
Clay soil remains wet and cold in winter and dries in summer. These soils consist of more than 25 percent clay and large amounts of water.
Silt soil consists of medium-sized particles, is well drained and retains moisture.
Peat soil contains a large amount of organic matter and retains a large amount of moisture.
Cretaceous soil is characterized by an excess of alkali due to calcium carbonate or lime in its structure.
Loam is a mixture of sand, silt and clay. These soils are fertile, easy to operate and provide good drainage. Depending on their prevailing composition, they can be either sandy or clay.
Soil formation
The soil is part of the earth's surface, consisting of disintegrated rock and humus, which provides an environment for plant growth. Soil development takes time and consists of a variety of materials that are inorganic and organic. Inorganic materials are non-living aspects of the soil, such as minerals and rocks, while organic materials are living soil microorganisms.
The process of soil formation is carried out through the mountain cycle along with the integration of microbial and chemical activity originating from living organisms. For example, during the decomposition of dead plants and animals, nutrients mix with weathered and destroyed rocks to form soil. Soil is considered a natural resource due to the benefits of agricultural productivity. Different soils have different mineral and organic compounds that establish their specific characteristics.
Soil categories
The following are common classification systems:
- geological classification;
- classification by structure;
- grading based on grain size;
- unified system;
- preliminary classification by soil type.
Based on the constituents, the soil can be classified as inorganic and organic.
Organic soil categories, in turn, are divided into the following types:
- residual;
- sedimentary;
- eolian;
- glacial;
- lake ones;
- marine.
According to the geological cycle, soils are formed as a result of disintegration and weathering of rocks. The soil is then subjected to compaction and cementation by heat and pressure.
Depending on the average grain size and the conditions under which soils are formed and deposited in their natural state, they can be assigned to the following categories of soil based on their structure:
- monogranular structure;
- honey comb structures;
- flocculation structure.
In the classification by grain size, they are indicated depending on the size of the particles. Terms such as gravel, sand, silt, and clay are used to refer to certain ranges of grain sizes.