PROPERTIES AND GENESIS OF THREE MEMBERS OF THE UPLANDS CATENA

Abstract

Field measurements were recorded of water table, Eh, moisture, and temperature for three members of the Uplands catena throughout 2 years. Samples of the Orthic Podzol (Uplands), Gleyed Orthic Podzol (Rubicon), and Orthic Gleysol (St. Samuel) were analyzed.High Eh values (above 600 mv) and a water table below 4 ft prevailed at the Uplands site. The soil had well-developed Ae and Bfh horizons. High Eh values prevailed at the downslope Rubicon site except for a few weeks each spring when the water table was at the surface. The soil had strongly developed Ae, Bhf, and Bfhg horizons. The water table remained at or near the surface at the depressional St. Samuel site. The Eh values in the upper 2 ft fluctuated appreciably; below this depth, they remained low (0 ± 150 mv). The brownish Bfg horizon was high in free iron oxide but low in organic matter and in free aluminum. Oxidation of ferrous iron from the underlying reduced-zone apparently contributed toward the development of this horizon.Montmorillonite is the dominant phyllosilicate in the Ae horizons and chloritized vermiculite in the B horizons of both Podzols. In St. Samuel, the dominant phyllosilicates are vermiculite in the Aejg horizon, and montmorillonite and mixed-layer material in the Bfg horizon.Morphological, chemical, and mineralogical properties of three members of the Uplands catena are related closely to redox conditions.