Background - Introduction
The original Soil Profile Analytical Database included in the European Soil Database (ESDB), known as SPADE-1 database, has limitations when applying models in a Pan-European context. SPADE-2 was developed to derive appropriate characterisation of soil profile data for Soil Typological Units (STUs) in the Soil Geographical Database of the ESDB (Hollis et al., 2006). SPADE 2 aims to provide sufficient soil property data to support higher tier modeling of pesticide fate at the European level.
Data supplied by each country were based on the national data archives and, for some parameters, particularly particle-size distribution, the analytical techniques used varied slightly from country to country. The raw data supplied by national data providers has thus been harmonised and validated to provide a single data file (SPADE_2.dbf) that can be easily used in conjunction with the SGDBE.
Harmonisation of particle-size data was carried out using a monotonic cubic spline interpolation procedure. Validation analyses have been carried out to ensure that any problems related to the harmonisation procedure were identified and corrected and that the range and population distributions of all parameters were consistent with expected patterns and ranges. Unusual outliers within parameter data sets were identified and, if necessary, corrected. As a result of the limitations of the SPADE-1 profile data for use in modelling at the European level, the European Crop Protection Association (ECPA), supported by the European Soil Bureau of the European Commission Joint Research Centre have sponsored the collation of a second profile database (SPADE-2) for use with the SGDBE. The overall objective was to provide sufficient soil property data to support higher tier modelling of pesticide fate at the European level.
Acquisition of soil property data
Derivation of the soil property data was achieved through the European Soil Bureau Network.
The first phase of acquisition resulted in data sets from Belgium and Luxembourg, Denmark, England and Wales, Finland, Germany, Italy, Netherlands, Portugal and Scotland (Hollis et al., 2006).
In a second phase of data acquisition providers from Bulgaria, Croatia, Czech Republic, Estonia, Greece, France, Hungary, Republic of Ireland, Latvia, Lithuania, Poland, Romania, Slovakia, Slovenia, Spain and Switzerland were contacted about participation. There was a negative response from Latvia and no reply from Croatia, Czech Republic and Poland. During subsequent negotiation of contracts, it was established that the specified data could not be supplied for Greece, Lithuania and Slovenia within the project time-scale. Bulgaria, Estonia, France, Hungary, Ireland, Romania, Slovakia and Switzerland supplied complete data sets by December 2008. Spain provided an interim dataset to be completed in summer 2009. The datasets from France and Ireland were developed from existing SPADE 1 data and literature using expert judgment. Annex 1 lists the data providers.
The current database (SPADE2v11) is a beta version of collated datasets from the first and second phases of soil profile data acquisition. A revised version will be available once datasets have been competed from Spain in late 2009.
As an introduction to SPADE-2 in general , you can consult SPADE-2: The Soil Profile Analytical Database for Europe (version 1.0), John M. Hollis, Robert J.A. Jones, Charles J. Marshall, Ann Holden, Jan Renger van de Veen and Luca Montanarella (2006). EUR 22127 EN .
As a further introduction to and documentation of SPADE2v11, you can read SPADE-2: Soil Profile Analytical Database for Europe Version 2.0 Beta Version March 2009, Jacqueline A. Hannam, John M. Hollis, Robert J.A. Jones, Pat H. Bellamy, Sue E. Hayes, Ann Holden, Marc H. Van Liedekerke and Luca Montanarella
Access to the SPADE2v11 database will be granted if you fill in the online form after which you will be provided with instructions on how to download the data.
The primary soil properties required for each STU are as follows: Horizon nomenclature [Upper depth (cm),Lower depth (cm)], Particle-size fractions: [(as a % of the less than 2mm fraction), clay, silt, total sand and content of at least 3 sand fractions (fine, medium, coarse)], pH in water (1:2.5) ,Organic Carbon content(%), Dry Bulk Density (g.cm-3).
SPADE2v11.dbf file comprises data in columns under the following category headings: SMU; STU; COUNTRY; USE; SOIL; PCAREA, HORIZON; DEPTH_UP; DEPTH_LO; CLAY; SILT; SAND_TOT; SAND_01; SAND_02; SAND_05; SAND_20; STONES; PH_KCL; PH_KCLSD; PH_H2O; PH_H2OSD; PH_CA; PH_CASD; OC; OC_SD; DB; DB_CALC; DB_UK_PTF; TEXT1; TEXT2; WR; WM1; WM2; WM3, SOIL_NEW, USE_NEW
It should be noted that the SPADE-2 database is made up of three separate types of data:
- Firstly, the soil property data for each soil HORIZON of each STU–USE (land use) combination. This is defined in columns headed HORIZON; DEPTH_UP; DEPTH_LO; CLAY; SILT; SAND_TOT; SAND_01; SAND_02; SAND_05; SAND_20; STONES; PH_KCL; PH_KCLSD; PH_H2O; PH_H2OSD; PH_CA; PH_CASD; OC; OC_SD; DB; DB_CALC; DB_UK_PTF. Only one line of data is included for each HORIZON.
- Secondly, there are data relating to each STU. This is defined in columns headed USE; SOIL; TEXT1; TEXT2; WR; WM1; WM2; WM3. These data are derived from the STU.dbf file of the SGDBE database and, for each STU-land use combination, is repeated for each soil HORIZON line. In some cases the data provider indicated different soil types or land uses that typify the SMU more accurately based on new data or expert judgement; this appears in SOIL_NEW and USE_NEW. The respective horizon data is therefore associated with the new soil type (SOIL_NEW) and land use (USE_NEW) entries rather than SOIL or USE as described in the spreadsheet and the STU.dbf file
- Finally, there are data relating to each SMU (soil map unit). This is defined in columns headed SMU, STU, PCAREA. These data are derived from the STUORG.dbf file of the SGDBE and, for each SMU-STU combination and is repeated for each soil HORIZON line.
Contacts - Acknowledgements
We thank the European Crop Protection Association (ECPA) for their generosity in financing this project and all our colleagues in the European Soil Bureau Network for their past and continuing collaboration in providing soil data and expertise for construction and enhancement of the European Soil Database. We also express our gratitude to: the National Soil Resources Institute (NSRI), Cranfield University for providing the infrastructure to undertake the work and finally to the Institute of Environment and Sustainability, Joint Research Centre, Ispra, Italy, for the support and encouragement throughout.