In the study of soil profiles, which of the following horizons represents the zone of eluviation where maximum leaching of clay, iron, and aluminum oxides occurs?

💡 Solution & Explanation

The E horizon is a mineral soil layer characterized by intensive eluviation, where percolating water washes out soluble minerals, clay particles, and metallic oxides, leaving behind a bleached, light-colored accumulation of quartz sand and silt. Plausible alternatives like the B horizon represent the illuviation zone where leached materials accumulate, whereas the O horizon consists primarily of organic litter. Soil scientists analyze these distinct master horizons to classify soil orders according to the United States Department of Agriculture taxonomy.