Illuviations

Part of speech: noun

Definitions

  1. The process by which materials such as clay, organic matter, or minerals are deposited or accumulated in a lower soil horizon after being leached from an upper layer ; a geological or pedological term describing the inward movement and concentration of substances within soil profiles ; the natural phenomenon involving the downward transfer and settling of soil components, causing layers to develop with distinct compositions
  2. The accumulation of soil particles transported from upper horizons and deposited in lower ones, particularly clays and organic residues ; a soil formation mechanism whereby displaced materials concentrate in subsoil layers ; the pedological action leading to distinctive soil layering through deposition of leached substances from above
  3. A soil science process involving the deposition of dissolved or suspended particles in subsurface layers after washing out from upper layers ; a ground process marking the formation of distinct layers by inward movement of materials like clay or humus ; the transformation of soil structure through the inward settling of fine components removed from overlying horizons

Etymology: "Illuviation" is the plural form "illuviations" refers to. It names the downward movement of fine particles such as clay, humus and iron compounds through the soil, carried by percolating water and deposited in a lower layer. The noun is built on the Latin verb "illuere", meaning "to wash into" or "to wash upon", which combines "in-" (into) with "luere" (to wash). The same Latin root gives the English "ablution", a washing away of impurities, and "lave", to bathe or wash. Because the term is a scientific coinage formed from classical parts, it is a modern technical word rather than one that existed in ancient usage. Soil scientists needed a name for the process of material being washed down and redeposited in the soil profile, and the Latin-derived term gave them a precise, neutral label.

Synonyms: soil depositions, soil accumulations, sediment deposits, soil translocations, soil layering