PHYSICAL AND CHEMICAL PROPERTIES OF A PODZOL (UPLANDS SERIES) WITH TONGUING B HORIZON

Abstract

Observations of a Humo-Ferric Podzol within a mixed deciduous forest in central Ontario showed vertical penetration of the parent C horizon by a tonguing Bf layer to depths greater than 2.5 m, in numerous localized areas of the soil. The tonguings were possibly initiated as white pine root casts formed by windthrow or in situ decay of undisturbed taproots. The role of these tonguings in the movement of water and solutes through the soil was assessed by comparing the physical and chemical properties of tonguing (Bf) and parent C2 horizons. In terms of the physical properties, there are only two distinct layers in the profile (the A + B and the BC + C1), while for CEC, organic matter and soil pH, there are four horizons (A, B, BC, and C1). The data suggest that tonguings are major conduits for water and solutes moving through the soil, and that processes such as nutrient cycling are concentrated within the tonguings, with little activity in adjacent C horizons. Key words: Podzol, tonguing, acidification