Soil structure is determined by physical and chemical properties, and can be categorized into granular, crumb, blocky, laminate, prismatic, columnar, single-grain, or massive. Factors affecting soil structure include weather cycles, water phase changes, and biological processes. Soil’s ability to support plant life depends on its mineral and organic matter content.
Soil structure is the shape the soil takes based on its physical and chemical properties. Each individual soil unit in the overall structure is called a ped. Soil structure is most easily determined by taking a sample of soil that has not been disturbed and looking closely at its shape. The landform will fall into one of the following categories: granular, crumb, blocky, laminate, prismatic, columnar, single-grain, or massive.
Granular soil looks like crumbs. This soil is where the roots have permeated the soil. It should not be confused with gritty soil, which is very porous. Each individual particle of grainy soil does not fit into each surrounding foot because the shape of each individual foot is approximately spherical.
Blocky terrain looks like irregularly shaped blocks. The shape of each individual ped is caused by the peds that surround it. Each ped block can be subdivided into smaller blocks.
The peduncles of the ground platy are thin, flat and plate-like. They are oriented in the horizontal direction. This structure is commonly found in compacted soil.
Prismatic feet are vertical columns that can be several centimeters long and are located in the lower horizons. The columnar feet are also vertically oriented columns but are topped with a salt “cap”. Columnar soil is found in arid regions of the world.
Single-grain soils are divided into individual soil grains that do not stick together and generally remain loosely packed. This property is located in sandy soils. Massive soil structure, on the other hand, appears in solid masses and does not have the propensity to break easily under light pressure. This structure is associated with very fine textured soils, such as clay.
Soil structure is determined by many factors, including climate, physicochemical and biological processes. Weather cycles have a significant effect on soil structure. Freezing and thawing, wet and dry, clay translocation and other various pedogenic – soil forming – processes affect the entire soil structure to different degrees throughout the structure. The effects are greatest in the top layer, where the exposure is direct.
The phase changes of water – solid, liquid and gaseous – have a dramatic effect on soil structure. These phases are influenced by the soil temperature. Flowing water causes soil to be eroded from one location and deposited in another location. The freeze-thaw and swelling process that changes the phase of water results in the change in soil volume.
Biological processes include the influences of organisms of various sizes in the soil. The amount of organic matter in the soil is a factor in how the soil aggregates and separates into stalks. Soil-dwelling animals help compact the soil in different ways. The secretions of these animals also affect the structure of the soil.
Another consideration when discussing soil structure is the soil’s ability to support plant life. Soils are made up of four different components: minerals, organic matter, air and water. Soils that contain 90% minerals and about 10% organic matter, also called humus, are able to support plant growth well. Soils that contain small amounts of organic materials have difficulty supporting plant life.
Protect your devices with Threat Protection by NordVPN
