GEOG 3360 Lecture Notes - Soil Horizon, Palygorskite, Halloysite
Document Summary
The cec of a soil, or its cation exchange capacity, is the maximum ability of a soil to hold cations available for exchange, and is expressed as milliequivalents/100 g soil. Various clay-size minerals have cecs that fall within certain limits, and by knowing the cec of the clay-sized fraction in the soil it is possible to estimate the clay minerals present. The soils data has been given for %c and cec for 100g soil and must be recalculated with respect to 100 g clay. The cec has been taken as a <2mm fraction, and recalculated with respect to the clay percentage in the soil samples. In order to calculate the cec and %c with respect to clay, it is done for 100g of soil. The soil amount of 100 g clay is divided by the total clay percentage, and then multiplied by the percentage of carbon to get %c per 100 g clay.
