What Is Soil Compaction?

Soil compaction refers to the process in which the soil bulk density increases and the soil porosity decreases correspondingly under the action of external forces. Vehicles, agricultural machinery, land improvement equipment, rolling of civil engineering machinery, and overgrazing are all human factors that cause this process, that is, secondary causes; natural causes can also induce soil compaction. For example, the large amount of clay deposits changes the composition of the soil particles to a certain degree, the heavy pressure of the overlying soil layer and other factors that affect the soil compaction process due to non-artificial reasons: soil moisture content, in general, contains The higher the amount of water, the easier it is to compact; the soil texture; the direction and location of the application of positive pressure; the size of the bearing surface. Soil compaction is a soil degradation process and an important cause of soil physical degradation. It will deteriorate soil physical properties, hinder soil aeration and water permeability, reduce soil's ability to support plant growth, and even cause increased surface runoff and increase environmental load. ^[1]

Soil compaction

In addition to moisture, soil texture, clay mineral types, and organic matter content affect soil compaction. Generally thick soils, soils with 2: 1 clay mineral content and soils with low organic matter content are more susceptible to compaction.
In order to prevent soil compaction, farming or field operations should be avoided when the soil is too wet, and the compaction resistance is strong when the soil moisture content is low; the number of operations should be minimized or the use of less tillage, no-tillage methods, or Combined operations, etc .; When carrying out field operations, selecting short operating routes or fixed lanes, reducing compaction area and selecting suitable farming speed can reduce compaction; improve farming tools, develop rotary, vibration or more Light farming tools can help reduce the compaction effect; through reasonable farming, such as the combination of conventional and deep tillage with organic fertilizers, and measures to promote the freezing and thawing of the soil and the wet and dry conditions, soil compaction can be prevented. ^[2]

application

Soil Compaction Construction Industry

Increasing the density of the soil and its side effects, including increasing strength and reducing permeability, usually achieve satisfactory results in civil engineering and building foundation construction. Soil compaction is usually done using heavy machinery. These devices often shake sand and gravel, causing soil particles to relocate and form dense structures. Rollers are often used on soil made of silt or clay to increase the strength of soil in a small area and drive air out of the soil.

The result of soil compaction is determined by the bulk density and compared with the maximum density. For example, get results from Proctor's compaction test to determine its "relative hardness." ^[3]

Soil compaction agriculture

Agricultural soil compaction is of concern to many agricultural soil scientists and farmers, as soil compaction may reduce plant growth. This may clearly observe rut marks. In any case, it cannot be said that all compaction will reduce plant growth. This topic is complicated because it concerns the plant's response to soil structure and water supply. Therefore, it is necessary to understand the gravity distribution of the application layer below the soil and the results of soil damage and deformation.