2013 年 57 巻 1 号 p. 27-44
The soils in Saskatchewan in the Central Interior Plains of Canada vary from semi-arid to sub-humid climates and between parent materials deposited during deglaciation. The Brown and Black Chernozem soils are the zonal soils of the grassland in the semi-arid to sub-humid climates. However, formation of intra-zonal soils depends on parent materials, e.g. the saline materials for Solonetz and clayey glacio-lacustrine sediments for Vertisol, and it also depends on topography, e.g. toe slope for Solonetz and depression for Gleysol. Under sub-humid climate, the zonal soils are Gray Luvisols in Boreal Transition Ecoregion. In Gray Luvisol soils under aspen forests, the downward fluxes of soil water are responsible for leaching of carbonate to deeper soil horizons and translocation of clays (lessivage) could be enhanced under the decreased salt concentrations in soil solution. Compared to Chernozem soils, Gray Luvisol soils are acidified as a result of leaching of carbonate, bases, and clays. In Dystric Brunisol (Cambisol) and Luvisol soils under coniferous forests (Mid-Boreal Ecoregion), the increased leaching is responsible for soil acidification through removal of carbonate and bases. As indicated by the high concentrations of Al and Fe in soil solution, incipient podzolization is also an active process involved in formation of Dystric Brunisol and Luvisol under lichen or moss cover, coniferous forests, and sandy parent materials, which could increase production and mobility of organic acids. The importance of climate and parent material on soil formation in Saskatchewan could be well characterized by analysis of soil solutions, along with solid soil analysis.
