The cation exchange capacity of a soil determines the number of positively-charged ions cations-that the soil can hold. This, in turn, can have a significant effect on the fertility management of the soil.
Why is cation exchange important in soils?
Cation exchange capacity (CEC) is a measure of the soil’s ability to hold positively charged ions. It is a very important soil property influencing soil structure stability, nutrient availability, soil pH and the soil’s reaction to fertilisers and other ameliorants (Hazleton and Murphy 2007).
How does cation exchange work in soil?
Cation-exchange capacity (CEC) is a measure of how many cations can be retained on soil particle surfaces. 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.
What is the role of cation exchange capacity in stabilizing the soil?
It was shown that the cation exchange in soil reduces the CH saturation in stabilized soil. If the CEC of soil is high, the CH in the pore solution of the stabilized soil may be unsaturated.
What are cations in soil?
Cations are positively charged ions such as calcium (Ca2+), magnesium (Mg2+), and potassium (K+), sodium (Na+) hydrogen (H+), aluminum (Al3+), iron (Fe2+), manganese (Mn2+), zinc (Zn2+) and copper (Cu2+). The capacity of the soil to hold on to these cations called the cation exchange capacity (CEC).
What is the role of cation exchange and base saturation in soil productivity?
Soils with high percent base saturation have a higher pH; therefore, they are more buffered against acid cations from plant roots and soil processes that acidify the soil (nitrification, acid rain, etc.). They contain greater amounts of the essential plant nutrient cations K+, Ca2+ and Mg2+ for use by plants.
How does CEC help the fertility of the soil?
It is the ability of the soil to hold or store cations. As CEC measures a soils ability to hold nutrients it is a key determinant of soil fertility. Soils with high CEC have the ability to hold more cations making them sufficient in calcium, magnesium and other cations.
What is CEC on soil test?
Cation exchange capacity (CEC) is a measure of the total negative charges within the soil that adsorb plant nutrient cations such as calcium (Ca2+), magnesium (Mg2+) and potassium (K+). As such, the CEC is a property of a soil that describes its capacity to supply nutrient cations to the soil solution for plant uptake.
Why does CEC increase with pH?
The higher the pH of the surrounding solution, i.e. higher OH ion concentration more H ions are attracted from the OH bonds of the clay structure and the higher the CEC of the clay.
What does CEC mean on soil test?
Cation exchange capacity
Cation exchange capacity (CEC) is a measure of the total negative charges within the soil that adsorb plant nutrient cations such as calcium (Ca2+), magnesium (Mg2+) and potassium (K+). As such, the CEC is a property of a soil that describes its capacity to supply nutrient cations to the soil solution for plant uptake.
What cations affect pH?
Note that all cations, except those of alkali and alkaline earth metals ( which do not hydrolyze in water and, therefore, do not affect pH ), act as weak acids in solution.
How is cation formed?
Summary. Cations form when an atom loses one or more electrons. The resulting cation has the electron configuration of the noble gas atom in the row above it in the periodic table.
How to improve soil CEC?
Test soils regularly,every other year if possible,to track soil acidity changes and to make timely adjustments if needed.
How to calculate cation exchange capacity?
H,meq/100g soil = 8 (8.00 – buffer pH)
What is a high cation exchange capacity?
Cation Exchange Capacity. A high CEC value (>25) is a good indicator that a soil has a high clay and/or organic matter content and can hold a lot of cations. A soil with a low CEC value (<5) is a good indication that a soil is sandy with little or no organic matter that cannot hold many cations.
What is the definition of cation exchange?
Cation exchange capacity (CEC) is a measure of the soil’s ability to hold positively charged ions. It is a very important soil property influencing soil structure stability, nutrient availability, soil pH and the soil’s reaction to fertilisers and other ameliorants (Hazleton and Murphy 2007).
