Proposed Classification for Human Modified Soils In Canada: Anthroposolic Order.

The aerial extent of disturbed soils is becoming larger and the disturbances more intense with increasing anthropogenic activity. Human altered soils cannot be described and classified using the Canadian System of Soil Classification (CSSC), thus an Anthroposolic Order is proposed. Anthroposols are azonal soils that have been highly modified or constructed by human activity, with one or more natural horizons removed, removed and replaced, added to, or significantly modified by human activities. Defining features are severe disruption of soil forming factors and introduction of potentially new pedogenic trajectories. Diagnostic horizons may not exist, materials may be foreign, and/or layers may not resemble natural soil horizons. Disturbed layers are designated D layers; they are anthropic in origin and contain materials that have been heavily manipulated physically and/or chemically by human activities. Three great groups are defined by presence of anthropogenic artifacts and organic carbon content. Subgroups are based on presence or absence of topsoil or a cover soil layer with higher organic carbon content than the horizons below it, on depth of disturbance, on drainage characteristics and water regime present at the site. Some new phases and modifiers, in addition to traditional ones used in the CSSC, are used with the Anthroposolic order. These new terms are based on chemical and physical properties and origins of anthropogenic artefacts. The proposed classification has been successfully applied to reclaimed profiles and is ready for widespread field testing.