The European Commission Joint Research Centre performed a study that identifies factors affecting the fate of buried objects in soil and develops a method for assessing where preservation of different materials and stratigraphic evidence is more or less likely in the landscape. The results inform the extent of the cultural service that soil supports by preserving artefacts from and information about past societies. They are also relevant to predicting the state of existing and planned buried infrastructure and the persistence of materials spread on land. Soils are variable and preserve different materials and stratigraphic evidence differently. This study identifies the material and soil properties that affect preservation and relates these to soil types; it assesses their preservation capacities for bones, teeth and shells, organic materials, metals (Au, Ag, Cu, Fe, Pb and bronze), ceramics, glass and stratigraphic evidence. Preservation of Au, Pb and ceramics, glass and phytoliths is good in most soils but degradation rates of other materials (e.g. Fe and organic materials) is strongly influenced by soil type. A method is proposed for using data on the distribution of soil types to map the variable preservation capacities of soil for different materials. This is applied at a continental scale across the EU for bones, teeth and shells, organic materials, metals (Cu, bronze and Fe) and stratigraphic evidence. The maps produced demonstrate how soil provides an extensive but variable preservation of buried objects.
The 4 maps come as 1 shapefile with an attribute table that contains 4 fields corresponding to the 4 parameters mentioned above:
- bones, teeth and shells (bones)
- organic materials (organics)
- metals (Cu, bronze and Fe) (metals)
- stratigraphic evidence (strati)
The values of the attrubutes vary between 1 and 3, as explained in the paper.
The geometry of the shapefile is the one of the European Soil Database. Areas of artificial surfaces, permanent ice or snow cover and water bodies were excluded from the analysis and only the polygons in the EU were considered for calculation. All the non-considered areas have a SoilID=0 and/or the 4 values for the 4 parameters equal 0.
These data/maps have been elaborated to the best of JRC’s knowledge. They are based on data publicly available in ESDAC, but the resulting dataset itself was never published for public or peer-reviewed scrutiny.
The Joint Research Centre study was conducted under the supervision of Gergely Toth.
Below is one example of the maps: "Soil-based preservation capacity for organic materials across the EU" as reported in the study mentioned above.