The article explores how different properties of soil, like water retention and cation exchange capacity, can be determined using measurements of clay, organic carbon, and other factors. By analyzing data from twelve types of soil, the researchers found that certain equations can accurately predict important soil characteristics like wilting point and field capacity. They also discovered that a quadratic equation involving clay and organic carbon can help determine available water capacity and penetrability of soil. Overall, the study provides simple methods to accurately assess key properties of soil.