In Situ Study of Podzolization on Tephra and Bedrock1
- Michael Singer,
- F. C. Ugolini and
- J. Zachara2
A study was initiated in the Washington Cascades to examine processes of soil genesis in situ through the analysis of soil solution chemistry. Suction plate lysimeters were used to continuously extract soil solution held below 0.1 atm from the O2, A2, IIB2hir, and IVB32 horizons of a forest soil. Movement of elements was in the order Si > Al > Fe > Mn. The O2 and A2 were the source of the Fe, Al, and Si which entered the IIB2hir. Most of the Mn originated in the A2. Virtually all of the Fe, 48.5% of the Al, 50% of the Mn, and 15% of the Si which left the A2 remained in the IIB2hir. According to the soil's morphology, it appears to be a Spodosol, and the lysimeter data indicates that podzolization is the major process of soil formation. The soil does not meet the criteria of a Spodosol in Soil Taxonomy. Two explanations for this are: (i) the soil has not become a Spodosol yet because the intensity of weathering is low or (ii) soil taxonomy criteria for the Spodosol order are not broad enough and need to be broadened to include soils of this type.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © .