Aluminum and CEC
Many heavily weathered or oxidized soils, especially in the wet tropics, have a high concentration of Al+3. Since aluminum is toxic in high quantities for most plants, there are certain advantages and disadvantages to this. For one, due to the relatively high adsorption rate of aluminum to soil colloids, it is taken out of the soil and the plant cannot use it. On the other hand, because it has 3 positive charges, it takes up a large amount of charge in a CEC. For example, Al+3 fills the same space as three NH4+ ions. This makes many aluminum heavy soils relatively infertile. There is no easy way to remove Al ions from the soil colloid and free the CEC for other ions.
Read more about this topic: Cation-exchange Capacity
Famous quotes containing the word aluminum:
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