The Reference Soil Group of the Anthrosols holds soils that were formed or profoundly modified through human activities such as addition of organic materials or household wastes, irrigation or cultivation.
Plaggic Anthrosols have the characteristic horizon plaggic produced by long-continued addition of `pot stable' bedding material, a mixture of organic manure and earth. The man-made character of the plaggic horizon is evident from fragments of brick and pottery and/or from high levels of extractable phosphorus (more than 250 mg P2O5 per kg by 1 citric acid).
The formation of most plaggic horizons started in the medieval times when farmers applied a system of `mixed farming' combining arable cropping with grazing of sheep and cattle on communal pasture land. In places, the system was in use for more than a thousand years evidenced by a plaggic horizon of more than 1 meter in thickness. Plaggic and Terric Anthrosols are well-drained because of their thickened A-horizon
The physical characteristics of plaggic and terric horizons are excellent: penetration resistance is low and permits unhindered rooting, the pores are of various sizes and interconnected and the storage capacity of available soil moisture is high if compared to that of the underlying soil material. Mild organic matter in the surface soil stabilizes the structure of the soil and lowers its susceptibility to slaking. The upper part of a plaggic or terric horizon may become somewhat dense if tillage is done with heavy (vibrating) machinery.
Based on the SGDBE Anthrosols cover land area in Europe predominantly around Belgium, the Netherlands and, to a smaller extent, in north-west Germany. Anthrosols form associations mostly with Podzols, Gleysols and Arenosols.