Brunisolic soils of Canada: genesis, distribution, and classification. (Special Issue: Soils of Canada.)

摘要

Brunisols are considered as moderately developed soils formed under forest cover. They have a wide range of physical and chemical properties and no single dominant pedogenic process drives the development of these soils. Brunisols are some of the more common soils in Canada, occupying over 1.2 million km2 of land, roughly equivalent to the area of Podzolic soils, and about half the area of the most common soil order in Canada, the Cryosols. Brunisols occur mainly within the boreal forest regions, but extend across the country with the exception of the Arctic and prairie regions. Within the zone of discontinuous permafrost they co-exist on landscapes with Cryosols. In humid regions of both eastern and western Canada they form a continuum of soil development with Podzolic soils. Within subhumid to semi-arid regions they often co-exist with Luvisolic soils, occurring on parent materials too coarse to enable Luvisolic soil formation. Brunisols equate closely to the Cambisol reference group in the World Reference Base taxonomic system and to several suborders of the Inceptisol order in Soil Taxonomy. Both Melanic and Sombric Brunisols are important agricultural soils in British Columbia, Ontario and the Maritime provinces. Eutric and Dystric Brunisols support commercial forest stands throughout the boreal forest and western cordillera of Canada.