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7.4: Activity 3 - Soil Charge Calculations

  • Page ID
    14463
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    Name: ______________________________

    Section: _____________________________

    Student ID#:__________________________

    1. A prairie soil contains 30% clay. This clay-sized fraction is dominantly montmorillonite. The soil also contains 5% humus (organic matter).

    a. Using the mineralogy method, what is the cation exchange capacity (CEC) contributed by the clay?

    b. What is the estimated cation exchange capacity (CEC) contributed by the humus?

    c. What is the total estimated CEC of this soil?

    The following is actual laboratory data for the soil in the example:

    Screen Shot 2021-06-23 at 21.10.56.png

    d. Calculate the CEC from the data in the table using the sum of cations method.


    This page titled 7.4: Activity 3 - Soil Charge Calculations is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Anna R. Schwyter & Karen L. Vaughan (UW Open Education Resources (OER)) via source content that was edited to the style and standards of the LibreTexts platform.