Comparing
Warm Season and Snowmelt
Pedogenesis in
Soils
Randall J. Schaetzl and Scott A. Isard
This study compares the ionic
concentrations of soil solutions of sandy Spodosols (Podzols) in Alberta,
Michigan, USA, during both the warm season and snowmelt. Also, a computer hydrologic model was used
to estimate the daily amount of water moving into the mineral soil (out of the
litter) for 1957-1987. Soil solutions
were extracted in situ from soils, and ionic composition (Fe, Al, H)
determined, to examine processes of podzolization.
Results suggest that March and April
(snowmelt) are the main periods of soil leaching, each with larger cumulative
infiltration events and greater total infiltration than any warm season
month. Warm season pedogenesis may
primarily involve upper solum weathering of primary minerals, as suggested by
low soil solution pH and relatively high ionic concentrations in O, A and E
horizons. Thus, weathering intensity in
the warm season (within eluvial horizons) may exceed eluviation rates.
During snowmelt, soils may respond to the release and flush of organic acids, as indicated by higher concentrations of Fe and Al in the soil solutions of illuvial horizons. Findings suggest that in some environments, snowmelt may provide the main pedogenic pulse or pulses for Fe and Al translocation, and hence, pedogensis.