Soil and Beds

Weighted Cation Exchange Capacity Calculator

Weighted Cation Exchange Capacity provides a numerical answer for the task to combine two soil-layer CEC values by sampled depth. It does not replace the field checks described below.

Enter values for depth-weighted cec

Weighted Cation Exchange Capacity needs layer a cec, layer a depth, and layer b cec from one case.

Sensitivity of the Weighted Cation Exchange Capacity result

To compare alternatives, save the current result before changing Layer A depth. Label both cases so the source measurements remain clear.

Worked depth-weighted cec example

depth-weighted cec = weighted total ÷ total weight

The depth-weighted cec ratio uses Layer A CEC, Layer A depth, and Layer B CEC in the order shown. Continue with Soil Test Sample Count Calculator to allow for unusable samples when planning soil-test collection.

Weighted Cation Exchange Capacity evaluates layer a cec at 12 meq/100g, layer a depth at 6 in, and layer b cec at 7 meq/100g as 8.88 meq/100g.

Before entering layer a cec

Prepare Layer A CEC, Layer A depth, and Layer B CEC for Weighted Cation Exchange Capacity. Keep unrelated records separate.

Layer A CEC. Default in Weighted Cation Exchange Capacity: 12 meq/100g.
Layer A depth. Default in Weighted Cation Exchange Capacity: 6 in.
Layer B CEC. Default in Weighted Cation Exchange Capacity: 7 meq/100g.

Interpreting this depth-weighted cec value

Depth-weighted CEC belongs to the Weighted Cation Exchange Capacity scenario. Recalculate depth-weighted cec for another case.

Depth weighting assumes uniform bulk density within each layer. Check layer a cec before applying depth-weighted CEC. The Soil Moisture Deficit Calculator provides moisture deficit.

Field notes for Weighted Cation Exchange Capacity

Recheck the bed after settling, cultivation, or heavy traffic if those changes affect layer a cec. Soil Bulk Density Calculator addresses how to calculate soil bulk density from a dry core sample.

Depth-weighted CEC questions

How much soil variation can Weighted Cation Exchange Capacity show?

Only variation captured by the entered measurements. Several zones may need separate depth-weighted cec cases.

How does “Depth weighting assumes uniform bulk density within each layer.” affect depth-weighted cec?

Account for it in the source measurement for layer a cec; the formula has no additional correction for it.