Soil characteristics in relation to groundwater for selected Dark Brown Chernozems in southern Alberta

Abstract

Miller, J. J. and Chanasyk, D. S. 2010. Soil characteristics in relation to groundwater for selected Dark Brown Chernozems in southern Alberta. Can. J. Soil Sci. 90: 597Á610. Limited information exists on soil characteristics in relation to groundwater for undulating morainal landscapes of the Dark Brown soil zone in western Canada. A 4-yr (1985Á1988) field study was conducted in southern Alberta to investigate these relationships for selected Dark Brown Chernozems. Soil morphology, physical and chemical properties of the soil horizons, water fluxes in the saturated zone, and tritium content of shallow groundwater were determined at nine sites. Three Orthic Dark Brown Chernozemic soils occurred in groundwater recharge areas with water tables ]1.81 m, indicating that leaching of carbonates from the B horizons was consistent with downward groundwater flow. The other three Orthic soils occurred in groundwater discharge areas, and they may have developed because of deeper ( ]2.60 m) water tables. High water-soluble Na in these latter three Orthic soils suggested a sodic influence from a shallower water table sometime in the recent past. The two Calcareous Dark Brown Chernozems, and saline Calcareous Dark Brown Chernozem occurred in groundwater recharge areas. One calcareous soil at a lower slope position had a shallow (0.84Á2.02 m) water table, suggesting carbonates were brought upward into the Cca horizon from the groundwater. The other calcareous soil at the upper slope position had a deeper (6.62 m) water table, suggesting carbonates were leached downward and precipitated in the Cca horizon. The saline Calcareous Dark Brown Chernozem was located in an area of groundwater recharge with a deeper (4Á9 m) water table, suggesting that salinization likely occurred sometime in the past. Groundwater flow conditions during this study could not explain the genesis of some soils in this study area, suggesting that past groundwater, climatic, and environmental conditions need to be considered to explain the genesis of some relict soils. Les auteurs ont proce´de´a`une e´tude sur le terrain de quatre ans (1985Á1988) dans le sud de l'Alberta, dans l'espoir de pre´ciser ces liens pour quelques tchernozioms brun fonce´. a`cette fin, ils ont e´tabli la morphologie du sol, les proprie´te´s physiques et chimiques de l'horizon, le flux d'eau dans la partie sature´e du sol et la concentration de tritium dans la couche d'eau souterraine peu profonde a`neuf sites. Trois tchernozioms brun fonce´orthiques se trouvaient dans la zone de re´alimentation, avec une nappe phre´atique ]1,81 m, signe qu'il y avait constante lixiviation des carbonates des horizons B vers les eaux plus profondes. Les trois autres sols orthiques se situaient dans la zone d'e´mergence et il se peut qu'ils se soient de´veloppe´s en raison d'une nappe phre´atique plus profonde ( ]2,60 m). Dans ces trois sols, la forte concentration de Na hydrosoluble laisse croire a`l'incidence sode´e d'une nappe phre´atique plus haute lors d'un passeŕ e´cent. Les deux tchernozioms cal...

Unsaturated water flux at mid and lower slope positions within an inclined landscape of the Dark Brown soil zone in southern Alberta

“…These unsaturated fluxes were also consistent with saturated fluxes ( (6.23 )10 (10 m s (1 ) that were measured between 25 and 35 m depth at this same site (Miller and Chanasyk 2010). Zebarth and de Jong (1989) Daily water flux directions at the lower slope position in 1985 were upward from May 16 to Jun.…”

“…Parameters estimated from soil water characteristic curves using RETC model (van Gehnucten et al 1991). The exception was saturated hydraulic conductivity, K s , which was determined directly on soil cores in the laboratory using constant head method (Miller et al 2010), and with this site being identified as a ''local recharge'' area for saline seepage at lower slope positions (Miller 1989).…”

“…The mid slope site was located in a local groundwater recharge area (Miller 1989;Miller and Chanasyk 2010) and the lower slope site was located in a groundwater discharge area and was a classified as a side-hill saline seep caused by local groundwater flow (Miller 1989;Miller et al 1993). The mid and lower slope position sites were previously referred to as Sites C1 and C2, respectively (Miller 1989;Miller et al 1993;Miller and Chanasyk 2010). Land use at the mid slope site was annual cropping (cereal-oilseeds) and at the lower slope position it was permanent grass cover.…”

“…The landscape is inclined to steep, low relief, and with a limiting slope of 9%. The mid slope site was classified as an Orthic Dark Brown Chernozem and lower slope position classified as a saline Gleyed Regosol (Miller 1989;Miller et al 1993;Miller and Chanasyk 2010).…”

“…In landscapes with significant relief and well-defined recharge and discharge sites, deep drainage generally occurs at mid and upper slope positions where the water table is deeper and upward flow into root zone generally occurs at lower or depressional slope positions with shallower water tables (Greenlee et al 1968;Leskiw 1971;Eilers 1973;Maclean 1974;Maclean and Pawluk 1975;Miller et al 1985Miller et al , 1993Stein and Schwartz 1990;Hayashi et al 1998;Miller and Chanasyk 2010).…”