The downward translocation and precipitation of eluvial materials at lower subsoil depths:________?
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Answer: C. Illuviation
Explanation
Illuviation refers to the downward translocation and precipitation of eluvial materials. Leached particles from upper surface horizons accumulate within lower subsoil depth zones. This process creates diagnostic subsoil horizons enriched in clay, iron, aluminum, or humus. Soil profile development is driven by opposing processes of removal and accumulation. Eluviation washes soluble and suspended materials out of upper E horizons. Subsequent illuviation deposits these transported materials into underlying B master horizons.
Identifying illuvial accumulation horizons is essential for classifying soils into proper taxonomic orders. Clay-enriched illuvial subsoils can restrict root penetration and impede internal drainage. Geomorphologists study illuviation patterns to understand landscape stability and weathering history. Iluviation is a misspelled variation lacking standard pedological acceptance in scientific literature. Eluviation describes the removal or export of materials from upper soil horizons. Melanization involves the darkening of surface mineral soils through the accumulation of organic matter.
- Subject
- Agriculture
- Category
- Agriculture
- Topic
- —
- Difficulty
- medium
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