The identification of plaggen soils using external beam microPIXE analysis

Abstract

AbstractPlaggen soils are man‐made agricultural soils which were created in historical times by using peat or turf as animal bedding. This bedding was then spread onto fields to create a rich and unusually deep topsoil. The plaggen system was used in Northern Europe from the Middle Ages up to, in some cases, the 1960s. Plaggen soils can be difficult to distinguish from soils which have simply had manure added, and in this paper we report the use of Proton Induced X‐Ray Emission (PIXE) to investigate the levels of nutrient elements, particularly phosphorus, in soils from a farm in Shetland which is known to have used plaggen soils until 1967. Elemental maps obtained in air using the University of Surrey External Beam system allow us to identify peat fragments which contain significantly elevated levels of phosphorus relative to fresh peat and relative to the surrounding soil matrix. A further finding is that the peat fragments also contain elevated levels of bromine which can be used to distinguish plaggened peat from manure. This technique will be applied to a study of the origins of the plaggen method. Copyright © 2011 John Wiley & Sons, Ltd.