| Pimple mounds are generally quasi-circular, micro-topographic features less than 1 m high and up to 20 m in diameter. When truncated by cultivation, mounds may appear on aerial photographs as a regular pattern of small, light-toned patches contrasting with the surrounding darker soil. This study describes the spatial distribution of ten pimple mound sites in southern Saskatchewan, and examines the morphology and composition of individual mounds at the Little Manitou Lake site near Watrous, Saskatchewan, Canada. Most known Saskatchewan mound sites are within the flat to undulating grasslands of the Prairie Ecozone and in the meltwater channels and gravelly outwash plains associated with massive glacial spillways. Although truncated mounds are still visible on some aerial photographs, few intact mound sites are found.; At the Little Manitou Lake mound site, mounds had a density of between 2.25 and 16.96 mounds per hectare and an average spacing between 22 and 48.03 metres. Mounds were quasi-circular in shape, an average of 0.36 m high, 14.7 m in diameter and 9.8 m3 in volume. Trenches through three mounds showed gravel-rich, highly bioturbated soil horizons.; Results of this study support the biological hypothesis that advocates mounds are formed due to bioturbation by burrowing animals and their predators. In areas where thin soils overlay a rigid subsurface material, burrowing animals create thick, well-drained mound soils over time by moving soil towards their nest as they construct their network of subsurface burrows. Mound formation is considered a polygenetic process that continues to operate today. |
