Date of Award
Doctor of Philosophy
This study was undertaken with the intention of quantitatively characterizing arctic soils in terms of variations within profiles, and between profiles along a micro-environmental gradient. A suite of soils forming a catena in north central Keewatin (65(DEGREES)27' N, 96(DEGREES)38' W) was investigated. Forty-five variables representing particle size properties, bulk density, moisture content, pH and exchangeable cations, the iron, aluminum and manganese extracted by dithionite, oxalate and pyrophosphate solutions, and various organic fractions were determined for each of 149 soil samples.;Characterization of the variations in these data was conducted using student's t-tests, analyses of variance and multivariate discriminant functions to differentiate among groups of samples which correspond to horizons and to slope segments suggested by the inherent regularity of site conditions and vegetation composition.;Differences between horizons were found to be characterized by organics (notably the sum of soluble and insoluble fractions determined using Kononova's (1966) technique), with pH, "free" iron (Fed), bulk density, and certain particle size fractions further distinguishing A, B and C horizons. "Norms" depicting the depth-distributions of variables displayed no general evidence indicative of illuvial accumulation in B horizons, however several properties suggest that eluviation has been operating. Surficial accumulation of organics (and perhaps aeolian detritus) appears to represent the dominant pedogenic mechanism, although relatively weakly expressed. A, B and C horizons are generally gradational.;Differences between profiles were also assessed using group-differentiating statistical techniques since both vegetation composition (especially lichens) and site variables were found to represent discrete segments along the transect. Differences in soils between these segments were characterized by particle size variations (notably silt enrichment in A horizons of "snowpatch" sites), "free" manganese (characteristically depleted in A horizons below the snowpatch), the "iron activity" ratio (Feo/Fed--exceptionally high in B and C horizons at the crest and summit) and the ratio of "complexed" to "free" iron (diminished in the B horizons of the solifluction scar area, and enhanced at the toe of the slope). Lateral variations in the pedogenic mechanisms identified above were found to be sensitive to even subtle variations in microenvironment along the catena. Soil taxa, however, were much less successfully characterized by the compositional data.
Banting, Douglas Ralph, "Characterization Of Arctic Soils: Interrelationships With Site And Vegetation" (1982). Digitized Theses. 1201.