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The deposition in an underlying soil layer of colloids, soluble salts, and mineral particles leached out of an overlying soil layer.

[illuvial, resulting from illuviation (in- + -luvial, relating to the action of flowing water, as in alluvial) + -ation.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Geological Science) the process by which a material (illuvium), which includes colloids and mineral salts, is washed down from one layer of soil to a lower layer
[C20: from Latin illuviēs dirt, mud, from il- + -luviēs, from lavere to wash]
ilˈluvial adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ɪˌlu viˈeɪ ʃən)

the accumulation in one layer of soil of materials that have been leached out of another layer.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
Boron (B) is involved in important soil processes (Kovda 1973): the intra-soil biological cycle; humification; isomorphic substitution in clay minerals and the formation of colloids; and illuviation. Goldschmidt (1937) found that B is concentrated in the uppermost humus layer of forest soils.
These sediments then undergo diagenesis under an anoxic and reducing conditions with subsequent sulfide production (similar to the process of illuviation described by Fanning et al.
Similar observations were made for other irrigation treatments of this soil, and in some cases, illuviation of micro-aggregates and clay particles was demonstrated by the turbid appearance of leachate for the clean water treatments.
In the Bw horizon of the Anthropic IBE there was a pattern of coalesced oxidic microaggregates, associated with features of incipient clay illuviation (argillans) (Fig.
Observation using polarised microscopy, thin sections of a Lien-Hua-Chi (LHC) soil sample with fine texture indicated that in all argillic horizons, b-fabrics might be attributed to strong illuviation of clay.
The dramatic difference in soil texture between the sites is likely to have also resulted in differences in water-holding capacity, nutrient status, bioturbation rates, illuviation rates, oxygen diffusivity, litter quality, root penetration resistance, and net primary productivity.
Cutans are prominent in many of the profiles, indicating illuviation from overlying horizons in the past and present (Vepraskas et al.
Our results suggest that differences in [K.sub.G] of different clay fractions may also be implicated in clay illuviation and soil genesis.
Instead, the presence of parna (Butler 1956), and the illuviation argillans on the sands, suggest that the area has been receiving dust.
The features most important for the classification are the presence of E horizon and abundance of clay illuviation features.
The dominance of forest vegetation in this region does not help matters as SOM and nutrients are recycled downwards through illuviation unlike in grass land vegetations.
This soil was classified as Eutric Fluvic Arenosols with weak features of illuviation process development and sand and clay contents of 70.5-86.4% and 0.3-2.6%, respectively.