HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Schumacher, B. A. Articles by Perkins, H. F. Search for Related Content PubMed Articles by Schumacher, B. A. Articles by Perkins, H. F. Agricola Articles by Schumacher, B. A. Articles by Perkins, H. F.

Soil Genesis in a Developmental Sequence of Soils Formed in Sillimanite Mica Schist Residuum¹

ABSTRACT

Dystochrepts formed in mica schist residuum occur on steeply sloping sideslopes, whereas associated Hapludults are found on gently sloping ridgetops in the Piedmont province of Georgia. In this study, morphological, physical, chemical, and mineralogical properties of Dystrochrepts and associated Hapludults were examined to determine the influence of weathering intensity differences within the pedon and across the Dystrochrept Hapludult developmental sequence. More intense weathering at the soil surface has resulted in higher exchangeable Al contents, lower pH values, and a relative accumulation of total Si, quartz, sillimanite, opaque minerals, and clay-sized mica and vermiculite. In contrast, biotite was more abundant at depth. Total Al was closely related to clay distribution within the pedon. Less intense weathering in the Dystrochrepts, apparently related to shorter development time, has led to coarser textured sola with higher base saturations, higher total Mg, K, and Na contents, and a greater abundance of fine sand-sized biotite and K-feldspar. Quartz in the fine sand fraction was concentrated in the Hapludult. Kaolinite was the dominant clay mineral in the Hapludult. Regularly interstratified mica-vermiculite was identified in subsurface horizons of the Dystrochrept and is believed to be a transitory intermediate in the transformation of mica to vermiculite.

¹ Contribution of the Univ. of Georgia, College of Agriculture, Agric. Exp. Stn., College Station, Athens, GA. This research was supported by state and Hatch funds allocated to the Univ. of Georgia Agric. Exp. Stn.

² Former Graduate Research Assistant (currently Postdoctoral Research Associate, Agronomy Dep., Louisiana State Univ., Baton Rouge, LA), and Professor of Agronomy, Univ. of Georgia, Athens, GA 30602.

Received for publication June 19, 1986.