Physical Properties of Soil
Soil Consistence
Soil consistence is a measure of the response of soil to mechanical stresses or manipulations at various moisture contents. It is determined by the cohesive and adhesive properties of the entire soil mass. Whereas structure deals with the shape, size, and distinctiveness of natural soil aggregates, consistence deals with the strength and nature of the forces between the sand, silt, and clay particles. Soils are rated for consistence as part of describing a soil profile and for estimating suitability for traffic and tillage.
Moisture Content Affect on Consistence
The consistence of a soil changes with moisture content and consistence can be described when the soil is wet, moist, or dry. When the soil is wet, its consistence can be described by two characteristics, stickiness (nonsticky, slightly sticky, sticky, or very sticky) and plasticity (nonplastic, slightly plastic, plastic, or very plastic). Stickiness refers to how well wet soil adheres to other objects (like your fingers) after pressure is released, while plasticity describes the malleability of wet soil. To determine stickiness, some soil is pressed between thumb and forefinger, and the amount that slicks to the fingers is noted. Clay soils generally show sticky consistence. Generally, coarse-textured soils are non-sticky. The plasticity of a soil is its ability to undergo deformation without cracking.
Click on the following topics for more information on physical properties of soil.
