Third meeting of the International Network of Soil Information Institutions (INSII), 31 October - 1 November 2017, FAO headquarters, Rome. Composed by institutions working on soil information in FAO member countries INSII provides expertise, and facilitates soil data/information sharing. Presentation by Kostantyn Viatkin, FAO.

2. Metadata
in the GSOС map
Konstantin Viatkin
GSP Secretariat

3. Metadata collection form

4. Metadata content - source data
• Total number of soil profiles/sampling locations;
• Type of sampling (profiles/augers/topsoil);
• Number of locations for each sampling method;
• Sampling Period (e.g. 1980-2007)
• Georeferencing (GPS coordinates/Location names);
• Depth of sampling
• Sampling design (e.g. transect, catena, land use etc.)

5. Metadata content - analysis methods
• Methods - Soil Organic Carbon analysis;
• Methods - Bulk Density (measured/estimated)
• Details about the sampling;
• Pedotransfer functions, default values, citations;
• External datasets (HWSD, SoilGrids.org);
• Methods - Coarse Fragments (measured/estimated/NA)
• Coarse fragments unit (e.g. % volume / % weight)
• Peat (sampling and description method);

6. Metadata content - upscaling
• Upscaling method (DSM / Conventional upscaling)
• The method(s) used (e.g. Multiple linear regression, R
Kriging, Random Forest...);
• Map quality measures (Digital Soil Mapping)
• Mean error (ME), Mean absolute error (MAE), root mean
squared error (RMSE), amount of variance explained (R2);
• Units (tonnes/ha, kg/m2);
• Resampling Method (if used)

7. Metadata content - contacts
• Submitter contact details;
• Institute (Data Holder / Handler);
• Citation;
• Update Frequency;
• Comments, Remarks

8. Countries’ reports: different
cases
• Previously published scientific reports
• Technical reports prepared for GSOC
• Basic overviews of the mapping activities

9. Published/ scientifically
reviewed reports

10. Technical reports for GSOC

11. Basic overviews

12. Density of sampling points
Total number of profiles/sampling locations used by countries to
create the global map is: 929 042.
Density of point data (per country):

13. Sampling period
timeframe countries
before 1990 24
before and
after 1990
45
after 1990 48 Metadata
table
fragment:

14. Type of sampling
Metadata
table
fragment:

15. Georeferencing accuracy
Metadata
table
fragment:

16. SOC analysis methods
Metadata
table
fragment:

17. Bulk density analysis methods
Metadata
table
fragment:

18. Coarse fragments methods
Data on coarse
fragments is not
available in
many countries

19. Upscaling methods
Metadata
table
fragment:

20. Upscaling methods
• Conventional Upscaling: Geo-matching, Class-matching;
• Digital Soil Mapping methods: Multiple linear regression,
Regression Kriging, Multivariate adaptive regression splines,
Generalized Linear Models, Generalized Additive Models, etc.
• Machine learning techniques: Random Forest, Support
Vector Machine, Neural Networks, Regression trees,
Bayesian trees, etc.
• Ensemble models combining different DSM methods;
• Geostatistical methods: Ordinary Kriging, IDW.

21. Common features from the
reports and comments
• Biggest challenges:
• data collection;
• consolidating data from different sources;
• new mapping methods;
• uncertainty assessment;
• Many countries plan to update their map next year, some
plan to update on regular basis.

22. Thank you
for your attention!