Vertisolic soils of Canada: Genesis, distribution, and classification

Abstract

Brierley, J. A., Stonehouse, H. B. and Mermut, A. R. 2011. Vertisolic soils of Canada: Genesis, distribution, and classification. Can. J. Soil Sci. 91: 903–916. The Vertisolic soil order is the most recent addition to the Canadian System of Soil Classification (1998). Soils of the Vertisolic order in Canada occur within the Brown, Dark Brown, and Black soil zones, associated with the Prairie ecozone. Due to the absence of swelling clays in central Canada, morphological characteristics of Vertisolic or vertic intergrades are not recognized in soils occurring to the east of Manitoba. Finetextured parent materials dominated by the presence of swelling silicate clays in conjunction with appropriate climatic factors are the principal soil-forming factors for these soils. Two Great Groups are recognized within the Vertisolic order: the Vertisol and Humic Vertisol. Soils of the Vertisol great group are associated with the arid portions of the Prairie ecozone, specifically the Mixed Grassland ecoregion, and Brown soil zone. Humic Vertisols occur within the Dark Brown and drier portions of the Black soil zone. Each Vertisolic soil great group contains three subgroups: Orthic, Gleyed and Gleysolic. Classification to this level is based upon the presence of mottles (reflecting the duration of soil saturation) within the upper 50 cm of the surface. Vertisolic soils develop in finetextured parent materials of high shrink-swell potential and pose problems for agricultural land use and engineering purposes.

Hydroclimatic controls on runoff activation in an artificially drained, near‐level vertisolic clay landscape in a Prairie climate

“…This is contrary to previous studies that have observed simultaneous OF and TF responses in clay soils and attributed this to rapid connectivity between the soil surface and tile drains (e.g., Smith et al, ). Such dynamics are expected to be most prevalent during intense summer rainstorms on dry soils when desiccation cracks are maximized, as the montmorillonitic clays of the RRV form extensive networks of vertical and lateral cracks when their moisture is below field capacity (Brierley et al, ). Conversely, such dynamics are expected to be less prevalent under wetter conditions when desiccation cracks close due to swelling (Hardie et al, ; Robinson & Beven, ).…”

“…Vertisolic clay soils are prevalent in several parts of the world including substantial proportions of RRV (Brierley, Stonehouse, & Mermut, ). Vertisols differ from other clayey soils by their ability to shrink and swell in response to moisture differences (Kurtzman, Baram, & Dahan, ).…”

Preferential Flow in Vertisolic Soils with and without Organic Amendments

“…Annual evapotranspiration exceeds precipitation, and seasonal ground frost develops down to 75 to 100 cm depth. Soils are Gleyed Humic Vertisols of the Red River Series (Brierley et al, 2011; Gleyic Humicryerts in the US taxonomy), and nearby soil survey pits show evidence of historical cracking, that is, cracks filled with black, organic-rich topsoil down to 75 to 100 cm depth.…”

Potential role of soil properties in the spread of CWD in western Canada

“…The clay mineralogy of soils across the CWD-endemic region of the prairie provinces is dominated by smectites (mostly Mte), with smaller amounts of mica, kaolinite and chlorite 29,[32][33][34][35][36] ( Fig. 3B).…”