Fourth Working Session of the International Network of Soil Information Institutions (INSII) 6-8 November 2018 | FAO HQ – German Room, Rome, Italy

1. Proposal
Specifications for the T1 and T2
soil profile databases of GLOSIS
Bas Kempen, Niels Batjes, Luis de Sousa,
Yusuf Yigini, Kostiantyn Viatkin

2. Pillar 4 Implementation Plan
• Three kinds of GLOSIS data products:
• Soil profile and point data
• Global polygon coverage, as replacement of FAO/UNESCO SMotW, 1:5M
• Global Grids:
• Harmonized World Soil Database, version 2
• Fine-resolution grid of soil properties, version 0 (collation of grids, 1km)
• Fine resolution grid of soil properties, version 1 (harmonized, <1km)
• Soil profile and point data
• Tier 1 - Comprehensive soil profile and analytical database.
• Tier 2 – World reference soil profile and analytical database (controlled, quality-
assessed).
• Provided through web-services in a federated way.

3. Soil profile description status
No Status Description
1 Reference profile description No essential elements or details are missing from the description, sampling or analysis. The
accuracy and reliability of the description and analytical results permit the full characterization of
all soil horizons to a depth of 125 cm, or more if required for classification, or down to a C or R
horizon or layer, which may be shallower.
2 Routine profile description No essential elements are missing from the description, sampling or analysis. The number of
samples collected is sufficient to characterize all major soil horizons, but may not allow precise
definition of all subhorizons, especially in the deeper soil. The profile depth is 80 cm or more, or
down to a C or R horizon or layer, which may be shallower. Additional augering and sampling
may be required for lower level classification.
3 Incomplete description Certain relevant elements are missing from the description, an insufficient number of samples
was collected, or the reliability of the analytical data does not permit a complete
characterization of the soil. However, the description is useful for specific purposes and provides
a satisfactory indication of the nature of the soil at high levels of soil taxonomic classification.
4 Soil augering description Soil augerings do no permit a comprehensive soil profile description. Augerings are made for
routine soil observation and identification in soil mapping, and for that purpose normally provide
a satisfactory indication of the soil characteristics. Soil samples may be collected from augerings.
5 Other descriptions Essential elements are missing from the description, preventing a satisfactory soil
characterization and classification.

4. Soil point data to be included (?)
• Only sampled profiles (by horizon or layer); aim is to have
measured data available.
• Countries may wish to document soil auger observations in their
own underpinning (national) dataset.
• Georeferencing: x,y coordinates only, or also allow other spatial
supports (e.g. field, representative profiles)
• Profiles should be correlated to the WRB for Soil Resources:
requirement for status 1 profiles that my be considered for the
T2spd (national classification can be included).
• T2spd: will need to meet the criteria for ‘soil profile description
status 1’.
• T2spd does not require a separate data model (or database); it
forms a subset of the T1spd.

5. Data collection
• Merging of various national dataset in GLOSIS requires
standardization (data structure) /harmonization (between
methods).
• According to uniform GSP P4/5 endorsed standards;
required for a bottom-up approach.
• Responsibility of each data provider. Guidelines/templates
will be provided.
• Copy of original data should be maintained.

6. Common GLOSIS approach
• Data stored following the Observations and Measurements (O&M) standard
(ISO/OGC). Defines a conceptual schema for encoding observations.
• An observation is an act that results in the estimation of the value of a feature
property, and involves application of a specified procedure, such as a sensor,
instrument, algorithm or process chain.
• Core set of properties for an observation:
• feature of interest = horizon of a profile
• observed property/attribute = SOC
• result/value = 1.2 %
• procedure/method = dry combustion
• Soil profile data expressed as results of observations and measurements.
• Database structure will be designed in such a way that the different tables can be
easily queried using feature, attribute, value and method.
• In-line with evolving principles for soil data exchange (SoilML, ISO-28258).
• (XML implementation by the OGC)

7. List of soil properties
• For properties considered in GLOSIS SPDB we follow
specifications for describing profiles according to the FAO
Guidelines and Soil and Terrain (SOTER) database
programme -> widely accepted and applied de facto
standards.
• Each profile characterized by site data and horizon data.
• Site: location (x, y coordinates), year of sampling, soil
classification (WRB, 2015).
• Horizon: upper and lower boundaries, properties.
• Supporting information on lineage: data owner, licence, data
source, source laboratory, analytical method used.

8. Proposed soil properties T2spdb
• Horizon depth (upper and lower limit)
• Horizon designation (FAO 2006)
• Matrix colour (moist and dry)
• Structure
• Texture (sand, silt, clay)
• Coarse fragments
• pH (H20 and KCl)
• Cation Exchange Capacity (CEC)
• CaCO3
• Soil Organic Carbon (SOC)
• Total Nitrogen
Incl. unit of measurement and analytical method used

9. Complementary soil properties
• See ‘Specifications for the Tier 1 and Tier 2 soil profile
databases of GLOSIS’ document for a full list:
• Appendix 1: site properties (largely based on FAO guidelines)
• Appendix 2: soil classification systems considered
• Appendix 3: horizon properties (with data type and unit)
• For T1spdb, all categorical variables must be harmonized to
the FAO guidelines.
• Spectral data: only store the values modelled from the
spectra; with clear descriptor that shows these data were
derived from proximal sensing.

10. Additional data tables
• Appendix 4: characterisation of laboratories and analytical
method descriptions.
• Appendix 5: registration of data ownership.
• Appendix 6: proposed list of site and horizon properties for
the T2spdb.
• Appendix 7: basic principles and templates for compiling a
profile data set.

11. bas.kempen@wur.nl
yusuf.yigini@fao.org

12. Data exchange