Data are available for the following Chemical properties:
- pH (measured in H2O)
- pH (n CaCl2 0.01 M solution)
- Cation Exchange Capacity (CEC)
- Calcium carbonates (CaCO3)
- C:N ratio
- Nitrogen (N)
- Phosphorus (P)
- Potassium (K)
Note that these data are based on the LUCAS topsoil data for ca 22,000 samples across EU.
Resolution: 500m; Format: geo TIFF; projection information: ETRS89 / LAEA Europe
Geographical Coverage: European Union (EU-26 excluding Cyprus and Croatia)
Input data: LUCAS 2009 Topsoil 22,000 sample point data
Model: Gaussian process regression (GPR)
The Physical proerty maps ( clay, silt and salt content; coarse fragments; bulk density; USDA soil textural class; available water capacity) are available in ESDAC from september 2015. In September 2019, we conluded the development of the LUCAS Chemical parameters [pH, pH CaCl, Cation Exchange Capacity (CEC), Calcium carbonates (CaCO3), C:N ratio, Nitrogen (N), Phosphorus (P) and Potassium (K)] and we made them available for download together with the scientific publications.
With 22,000 sampled locations the LUCAS soil database is unique in Europe for the number of available observations, its spatial coverage and its temporal resolution. While LUCAS point data are available upon request from the European Soil Data Centre (ESDAC), the interpolated maps of chemical properties offer a better overview of the distribution of soil chemical properties in the EU to the scientific community and to policy makers. The derived maps will establish baselines that will help monitor soil quality and provide guidance to agro-environmental research and policy developments in the European Union. The chemical properties datasets, together with the physical properties, contribute to one of the main objectives of the GlobalSoilMap project.
The modelling is based on Gaussian Process Regression technique that allows the estimation of prediction uncertainty. The best performing prediction was obtained for the C:N ratio (R2=0.91), followed by phosphorus and potassium (R2=0.75). The performance prediction of the rest of chemical properties in terms of R2 is higher than 0.60 with the exception of CEC (R2= 0.35).
Topsoil pH is influenced by soil parent material, erosional effects, climate and vegetation. The calcium carbonate content is highly correlated with pH, having similar influencing factors. Soil nitrogen distribution is dependent on soil organic carbon, vegetation and climate and soil texture. The land use appears to be the main driver for phosphorus content in soils, as agricultural areas have higher concentrations due to fertilizer application. CEC is influenced by the clay distribution in soils, topography and parent material.
Ballabio, C., Lugato, E., Fernández-Ugalde, O., Orgiazzi, A., Jones, A., Borrelli, P., Montanarella, L. and Panagos, P., 2019. Mapping LUCAS topsoil chemical properties at European scale using Gaussian process regression. Geoderma, 355: 113912.