The sum total of exchangeable cations adsorbable by the porous medium; expressed in moles of ion charge per kilogram of porous media.
the capacity of a soil to adsorb cations; cations are adsorbed at exchange sites, and can be released in exchange for other cations.
Cation exchange capacity (CEC): a measurement of the capacity for soil particles to hold onto positively charged ions (cations) Cation exchange capacity is an important measurement of garden soils because it expresses the ability of the soil to hold onto nutrients (ions) with a positive charge like magnesium, potassium, hydrogen, calcium, copper, zinc, etc). The CEC is largely attributed to the clay content and the organic matter content of the soil. Each of these has the capacity to hold onto positively charged nutrients. Sandy soils have a low CEC while clay soils have a high CEC. The expression of CEC is typically given in milliequivalents (meq) per 100 grams of soil. Loamy soils range from 15 to 30 meq. It takes more lime to raise the pH of a clay soil (with more exchangeable sites for cations) than it does a sandy soil.
The ability of clay and high organic matter (humus) soils, which contain negatively charged particles, to attract and exchange positively charged ions called cations. These cations, such as calcium, potassium, magnesium and ammonia, are thus held in the soil and are not lost due to leaching.
The capacity of a soil to exchange and retain positively charged ions (cations) expressed in terms of milliequivalents per 100 grams of soil (me/100 g).
The ability of a soil's colloids to attract and hold onto its cations. Soils high in humus and expanding clays tend to have the highest CECs.
A measure of the total amount of exchangeable cations that can be held by a soil. It is expressed in terms of milli-equivalent as per 100 grams of soil at pH7 unless stated otherwise.
total number of cations a soil can absorb, expressed in centimeters of charge per kilogram (cmolc/kg) of soil.
Represents the total quantity of negative charge that is available in the soil to attract positively charged ions in the soil solution.
Often abbreviated CEC, a measure of the ability of a medium to adsorb positive ions, or cations. Many nutrients which are necessary for plants are in this form.
the total quantity of cations that a soil can adsorb by cation exchange, usually expressed as milliequivalents per 100 grams of soil. Measured values of cation exchange capacity depend somewhat on the method used for the determination.
relative number of sites on a particle that are negatively charged, as with clay or organic matter; attracts positively charged ions (like nutrients) and holds them until the plant needs to absorb them.
a measure of the negative charge on soils (primarily on clays and organic matter). It is expressed as the quantity of cations (positive ions) that can be adsorbed by the soil and is expressed in centimoles of charge/kg of soil (6x1023 charged particles are contained in one mole of charge).
Sum of exchangeable cations a soil can adsorb and retain against leaching and is expressed as centimoles per kg of soil or milliequivalent per 100 grams of soil. Sometimes referred to as the CEC.
The sum of exchangeable bases plus total soil acidity at a specific pH, values, usually 7.0 or 8.0. It is usually expressed in centimoles of charge per kilogram of exchanger (cmolckg-1) or millimoles of charge per kilogram of exchanger.
The total amount of exchangeable cations that a given soil can adsorb.
Sum of exchangeable cations a soil can adsorb at a specific pH – influences nutrient availability to plants. or The amount of negative charge that exists on humus and clays allowing them to adsorb cations.
The capacity of soil to hold nutrients for plant use. Specifically, CEC is the amount of negative charges available on clay and humus to hold positively charged ions. Effective cation exchange capacity (ECEC) is reported for acid soils (pH5). Expressed as centimoles of charge per kilogram of soil (cmolc/kg).
The surfaces of clay minerals and organic matter have negative electrical charges that attract positively charged elements or molecules (cations), which are exchangeable with other cations in the soil solution. The net negative charge of a given weight of soil is equivalent to the cation exchange capacity. CEC is especially important for the essential plant nutrients potassium, calcium, and magnesium. When held in exchangeable form on particle surfaces, these nutrients are protected from leaching and are a reserve nutrient supply that can replenish ions taken up by plant roots. Another important function of CEC is the exchange of hydrogen and aluminum cations between particle surfaces and the soil solution, which helps buffer soil pH (i.e., pH remains more stable because of the ability to exchange acidic cations).
The cation exchange capacity of a soil is an indicator of the number of cation exchange sites within the soil.
The capacity of a soil to exchange cations with the soil solution. Often used as a measure of potential soil fertility.
In soil science, cation exchange capacity (CEC) is the capacity of a soil for ion exchange of positively charged ions between the soil and the soil solution. A positively-charged ion, which has fewer electrons than protons, is known as a cation (pronounced ; cat-eye-on) due to its attraction to cathodes. Cation exchange capacity is used as a measure of fertility, nutrient retention capacity, and the capacity to protect groundwater from cation contamination.
