Cheluviation is the process in which the minerals are dissolved and transported downwards under the influence of chelating agents. Chelating agents are the organic acids produced after the decomposition of organic matter
Cheluviation is one of the process of soil formation.
Echolocation process is similar to leaching in that it involve downward movement of materials from upper soil to lower soil layer but they differ in how what causes the process. In cheluviation plant acid are involved in causing the movement while in leaching water alone is involved in causing the movement.