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Soil texture affects soil behaviour, in particular, its retention capacity for nutrients (e.g., cation exchange capacity) [8] and water. Sand and silt are the products of physical and chemical weathering of the parent rock ; [ 9 ] clay, on the other hand, is most often the product of the precipitation of the dissolved parent rock as a secondary ...
In soil science, soil gradation is a classification of a coarse-grained soil that ranks the soil based on the different particle sizes contained in the soil. [1] Soil gradation is an important aspect of soil mechanics and geotechnical engineering because it is an indicator of other engineering properties such as compressibility , shear strength ...
If the soil has 5–12% by weight of fines passing a #200 sieve (5% < P #200 < 12%), both grain size distribution and plasticity have a significant effect on the engineering properties of the soil, and dual notation may be used for the group symbol.
Cation-exchange capacity (CEC) is a measure of how many cations can be retained on soil particle surfaces. [1] Negative charges on the surfaces of soil particles bind positively-charged atoms or molecules (cations), but allow these to exchange with other positively charged particles in the surrounding soil water. [ 2 ]
CEC is the amount of exchangeable hydrogen cation (H +) that will combine with 100 grams dry weight of soil and whose measure is one milliequivalents per 100 grams of soil (1 meq/100 g). Hydrogen ions have a single charge and one-thousandth of a gram of hydrogen ions per 100 grams dry soil gives a measure of one milliequivalent of hydrogen ion.
The specific weight, also known as the unit weight (symbol γ, the Greek letter gamma), is a volume-specific quantity defined as the weight W divided by the volume V of a material: = / Equivalently, it may also be formulated as the product of density, ρ, and gravity acceleration, g: = Its unit of measurement in the International System of Units (SI) is newton per cubic metre (N/m 3), with ...
Available water capacity is the amount of water that can be stored in a soil profile and be available for growing crops. [1] It is also known as available water content ( AWC ), profile available water ( PAW ) [ 2 ] or total available water ( TAW ).
Available water is that which the plants can utilize from the soil within the range between field capacity and wilting point. Roughly speaking for agriculture (top layer soil), soil is 25% water, 25% air, 45% mineral, 5% other; water varies widely from about 1% to 90% due to several retention and drainage properties of a given soil.