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LECA is usually produced in different sizes and densities from 0.1 millimetres (0.004 in) up to 25 millimetres (1.0 in), commonly 0–4 mm, 4–10 mm, 10–25 mm and densities of 250, 280, 330, and 510 kg/m 3. LECA boulder is the biggest size of LECA with 100–500 mm size and 500 kg/m 3 density.
Extragrade features are aberrant properties which prevent that soil from being included in another soil classification. About 1,000 soil subgroups are defined in the United States. [6] A soil family category is a group of soils within a subgroup and describes the physical and chemical properties which affect the response of soil to agricultural ...
If the soil has more than 15% by weight retained on a #4 sieve (R #4 > 15%), there is a significant amount of gravel, and the suffix "with gravel" may be added to the group name, but the group symbol does not change. For example, SP-SM could refer to "poorly graded SAND with silt" or "poorly graded SAND with silt and gravel."
The Universal Soil Loss Equation (USLE) is a widely used mathematical model that describes soil erosion processes. [1]Erosion models play critical roles in soil and water resource conservation and nonpoint source pollution assessments, including: sediment load assessment and inventory, conservation planning and design for sediment control, and for the advancement of scientific understanding.
Soil erodibility is a lumped parameter that represents an integrated annual value of the soil profile reaction to the process of soil detachment and transport by raindrops and surface flow. [1] The most commonly used model for predicting soil loss from water erosion is the Universal Soil Loss Equation (USLE) (also known as the K-factor ...
A simplified version of the Emerson soil dispersion test [3] can be completed in the field on a 20-minute to two-hour timescale. Laboratory tests used to diagnose a soil as dispersive focus on the cation exchange capacity of a soil sample and its cation breakdown. Soil cations are dominated by Ca 2+, Mg 2+, K +, and Na +, as well as H + in ...
A gleysol or gley soil is a hydric soil that unless drained is saturated with groundwater for long enough to develop a characteristic gleyic colour pattern. The pattern is essentially made up of reddish, brownish, or yellowish colours at surfaces of soil particles and/or in the upper soil horizons mixed with greyish/blueish colours inside the ...
Soil piping is a particular form of soil erosion that occurs below the soil surface. [237] It causes levee and dam failure, as well as sink hole formation. Turbulent flow removes soil starting at the mouth of the seep flow and the subsoil erosion advances up-gradient. [ 238 ]