MAcYK, T. M., PewruK, S. AND LrNosey, J. D. 1978. Relief and microclimate as related to soil properties. This study was undertaken to determine the influence of relief and microclimate on soil properties. Seven sites were chosen at different positions on the nofth-and south-facing slopes of a moderately rolling till knob. Physical, chemical and mineralogical analyses were conducted to characterize the soils at each of the sites. The vegetation of the area was described and soil temperatures and moisture were monitored at four depths. Redox potential and pH were measured to detect seasonal variations. Data for oxalate and dithionite-extractable iron and aluminum, cation exchange capacity, and X-ray diffraction showed only minor differences among the seven pedons along the slope faces. Soil temperature was higher on the south-facing slope than on the north-facing slope and air temperature was usually higher than soil temperature at the 10-cm depth. Soil moisture regime varied with position in the landscape. The soil on the nonh-facing slope was generally more moist than the soil on the south-facing slope. Redox potential varied seasonally and appeared to be related to the moisture content of the soil.

The loess derived soils of the Hinton district provide a record of soil formation for the entire postglacial period. Loess originates from the shorelines of Brûlé Lake and from the sandbars and braided channels of the Athabasca River.The geochronology of the loess, as established through the study of paleosols and volcanic ash beds, indicates that loess deposition was continual but irregular. Soil formation occurred contemporaneously with loess deposition, and varying soil morphologies were attributed to differing local rates of loess accumulation. There was no evidence for marked climatic change during the Holocene in the study area, but increased loess supply after 4000 years BP may reflect gradual change.

Dulr.lNsxr, J., Wnrcnr, J. C. ,lNn Lrxos.tv, J. D. 1973

The high degree of variability peculiar to eral horizons to illustrate the results. In adanalytical soil survey data has generally pre-dition, significant correlation coefficients becluded its systematic character:ization.' ihi. tween-pr6perties of the A horizons are inpaper deals i'ith the application of the Statis-cluded.'It is expected that information yielded tical Prediction TechnlQue to such data and by this approich would be useful for soil contains eight contour maps of surface min-uiilizarion'and for field mapping.

ABSTRACTamorphous (to X-ray) humr.rs-iron nricropellers were identified with the use of au electron microscope. The relcase of iron oxide from the weatheriug of iron-rich cblorites was also evident and is suggested as a mechanism by which the aecretion of iron oxidc to a peilet form could be explained. The possitrle genesis of these rnicropellets is fuily discussed.