eluviáció

Eluviation is a soil science process where mineral particles, organic matter, and soluble substances are washed out from the upper layers of soil by percolating water. This downward movement of materials is a key component of soil formation and influences the development of distinct soil horizons.

The process of eluviation is most pronounced in humid climates where rainfall is sufficient to cause significant water infiltration. As water moves through the soil profile, it dissolves and carries away mobile constituents such as clay, silt, sand, iron oxides, aluminum compounds, and salts. The materials removed are then deposited in lower soil layers through a process called illuviation.

The rate and extent of eluviation are affected by several factors, including soil texture, structure, organic matter content, and the amount and intensity of precipitation. Sandy soils with poor structure tend to eluviate more readily than clayey soils with well-developed aggregation. Areas with high rainfall and poor drainage will experience more eluviation.

The depletion of minerals and organic matter in the eluviated horizon, often referred to as the A horizon or eluviation layer, can lead to a lighter color and a less fertile soil. Conversely, the accumulation of these materials in the illuviated horizon, typically the B horizon, can result in a denser, darker, and more nutrient-rich layer. The interplay between eluviation and illuviation is fundamental to the classification and understanding of different soil types worldwide.