WoSIS data sets
WoSIS data sets
We will serve a growing selection of standardized attributes from WoSIS using various formats:
- Static datasets: For consistent citation purposes, we serve static snapshots of the standardized data in TXT format. Each dataset is given a unique name and digital object identifier (DOI). For example, the set of data that has been standardised at the end of July 2016 has been made available as supplement to a data paper in ESSD (doi:10.5194/essd-9-1-2017); the dataset is available here.
- Dynamic dataset: This data set is served '24/7' from WoSIS through an OGC-compliant WFS (Web Feature Service) provided via Geoserver. The point data can be accessed from GIS and R, as described in the tutorial. Once the connection has been made, all currently available layers may be visualised in the GIS for further processing.
[Note: Being dynamic, the WFS-served version of the dataset will grow once new point data are added/processed, additional soil attributes are considered, and/or when possible corrections are required]
File naming conventions and descriptions as used for the dynamic WoSIS-WFS dataset#.
|bulk_density_fine_earth||Bulk density of the fine earth fraction < 2 mm (kg/dm3)|
|bulk_density_whole_soil||Bulk density of the whole soil including coarse fragments (kg/dm3)|
|calcium_carbonate_equivalent_total||The content of carbonate in a liming material or calcareous soil calculated as if all of the carbonate is in the form of CaCO3 (g/kg in the fine earth fraction < 2 mm); also known as inorganic carbon|
|organic_carbon||Gravimetric content of organic carbon in the fine earth fraction <2 mm (g/kg)|
|total_carbon||Gravimetric content of organic carbon and inorganic carbon in the fine earth fraction < 2 mm (g/kg)|
|Capacity of the fine earth fraction < 2 mm to hold exchangeable cations, estimated by buffering the soil at pH7 (CEC, cmolc/kg)|
|Capacity of the fine earth fraction < 2 mm to hold exchangeable cations, estimated by buffering the soil at pH8.2 (CEC, cmolc/kg)|
|Capacity of the fine earth fraction < 2 mm to hold exchangeable cations at the pH of the soil (ECEC, cmolc/kg). Conventionally approximated by summation of exchangeable bases (Ca2+, Mg2+, K+, and Na+) plus 1 N KCl exchangeable acidity (Al3+ and H+) in acidic soils|
|Ability of a 1:x soil water extract to conduct electrical current (ECx, mS/m); ECe refers to values measured in a saturated soil extract|
|coarse_fragments_gravimetric_total||Gravimetric content of coarse fragments > 2 mm in the whole soil (g/100g)|
|coarse_fragments_volumetric_total||Volumetric content of the coarse fragments > 2 mm in the whole soil (cm3/100cm3)|
|clay_total||Gravimetric content of < 0.002 mm soil material in the fine earth fraction < 2 mm (g/100g)|
|silt_total||0.002 mm to Y mm fraction of the < 2 mm soil material (g/100g); esd (equivalent spherical diameter), X resp. Y as specified in the analytical method descriptions|
|sand_total||Larger than Y mm fraction of the < 2 mm soil material (g/100g); esd (equivalent spherical diameter), Y as specified in the analytical method descriptions|
|water_retention_gravimetric||Soil moisture content by weight, at the tension specified in the analytical method descriptions (g/100g)|
|water_retention_volumetric||Soil moisture content by volume, at the tension specified in the analytical method descriptions (cm3/100cm3)|
|ph_cacl2||A measure of the acidity or alkalinity in soils, defined as the negative logarithm (base 10) of the activity of hydronium ions (H+) in a CaCl2 solution, as specified in the analytical method descriptions|
|ph_h2o||A measure of the acidity or alkalinity in soils, defined as the negative logarithm (base 10) of the activity of hydronium ions (H+) in water|
|ph_kcl*||A measure of the acidity or alkalinity in soils, defined as the negative logarithm (base 10) of the activity of hydronium ions (H+) in a KCl solution, as specified in the analytical method descriptions|
|ph_naf||A measure of the acidity or alkalinity in soils, defined as the negative logarithm (base 10) of the activity of hydronium ions (H+) in a NaF solution, as specified in the analytical method descriptions|
|soil_classification_WRB||Classification of the soil profile according to specified edition (year) of the World Reference Base for Soil Resources (WRB), up to qualifier level when available|
|soil_classification_FAO||Classification of the soil profile according to specified edition (year) of the FAO-Unesco Legend, up to soil unit level when available|
|soil_classification_Soil_Taxonomy||Classification of the soil profile according to specified edition (year) of USDA Soil Taxonomy, up to subgroup level when available|
# Similar naming conventions are used for the static snapshots, but then each name will be supplemented with the date of the snapshot, for example: ph_h2o_2016_July.
Feedback and questions
We are constantly adding new dat sets to WoSIS and improving the associated web services; your feedback would be highly appreciated!
If you are interested in sharing soil profile data for consideration in WoSIS please contact us with some details of the dataset (metadata).
Feel free to contact us if questions arise in the use of our analysis products; please indicate in your e-mail which product/release you are using.
Ribeiro E, Batjes NH, Leenaars JGB, Van Oostrum AJM and Mendes de Jesus J 2015.Towards the standardization and harmonization of world soil data: Procedures Manual ISRIC World Soil Information Service (WoSIS version 2.0). ISRIC - World Soil Information, Wageningen, 110 p. (PDF)
Batjes NH, Ribeiro E, van Oostrum A, Leenaars J, Hengl T, and Mendes de Jesus J 2017: WoSIS - Providing standardised soil profile data for the world, Earth System Science Data 9, 1-14 (PDF).
Tutorial (WFS set)
The text of the tutorial below, with illustrations, is available in PDF format.
a) GIS users
You may open the point layers by adding the following WFS in your GIS: http://wfs.isric.org/geoserver/wosis/wfs . Detailed instructions for GIS users may be found in the corresponding documentation (QGIS users ; ArcGIS users). For a WoSIS specific tutorial see here.
Entering the WFS-connection string into QGIS
b) R users
A more flexible way to access WoSIS points is to use the GDAL functionality (see WFS driver documentation for GDAL). For this we can use OGR functions ogrinfo and ogr2ogr (basically a translation function). Before you can start, make sure you first install GDAL binaries (do not come with rgdal). Under Windows OS, this requires first locating GDAL executables. If GDAL is installed and path known, we can request information about the data on the server by using the ogrinfo:
gdal.dir <- shortPathName("C:/Program Files/GDAL")
ogr2ogr <- paste0(gdal.dir, "/ogr2ogr.exe")
ogrinfo <- paste0(gdal.dir, "/ogrinfo.exe")
system(paste(ogrinfo, '-ro WFS:\"http://wfs.isric.org/geoserver/wosis/wfs\"'))
INFO: Open of ' WFS:http://wfs.isric.org/geoserver/wosis/wfs '
using driver `WFS' successful.
1: wosis:profile (Point)
2: wosis:bulk_density_fine_earth (Point)
3: wosis:bulk_density_whole_soil (Point)
4: wosis:calcium_carbonate_equivalent_total (Point)
5: wosis:organic_carbon (Point)
6: wosis:total_carbon (Point)
7: wosis:coarse_fragments_gravimetric_total (Point)
8: wosis:coarse_fragments_volumetric_total (Point)
9: wosis:clay_total (Point)
10: wosis:sand_total (Point)
11: wosis:silt_total (Point)
12: wosis:water_retention_gravimetric (Point)
13: wosis:water_retention_volumetric (Point)
14: wosis:ph_cacl2 (Point)
15: wosis:ph_h2o (Point)
16: wosis:ph_kcl (Point)
17: wosis:ph_naf (Point)
18: soil classification WRB (Point)
19: soil classification FAO (Point)
20: soil classification US Soil Taxonomy (Point)
This gives a list of layers currently available via WoSIS. For more info about the code names please refer to the official documentation.
c) Visualization of WoSIS data in Google Earth
Next, we would like to import points from WoSIS into R and then use them for analysis or visualize them in Google Earth. We can fetch only a subset of points i.e. clay content for a bounding box of 10 by 5 degrees (France) directly via the ogr2ogr:
system(paste(ogr2ogr, '-f \"ESRI Shapefile\" clay_total_sub.shp WFS:\"http://wfs.isric.org/geoserver/wosis/wfs " clay_total -clipsrc 0 45 10 50'))
Warning 6: Normalized/laundered field name: 'profile_layer_id' to 'profile_la'
Warning 6: Normalized/laundered field name: 'descriptor_id' to 'descriptor'
Warning 6: Normalized/laundered field name: 'profile_code' to 'profile_co'
Warning 6: Normalized/laundered field name: 'observation_date' to 'observatio'
Warning 6: Normalized/laundered field name: 'upper_depth' to 'upper_dept'
Warning 6: Normalized/laundered field name: 'lower_depth' to 'lower_dept'
Other conversion possibilities using the WFS driver are explained here. The output of the above operation will fetch only a few hundred points, which can now be imported into R
clay_total_sub <- readOGR("clay_total_sub.shp", "clay_total_sub")
OGR data source with driver: ESRI Shapefile
Source: "clay_total_sub.shp", layer: "clay_total_sub"
with 406 features
It has 15 fields
Note that these are in fact 3D points as they refer to different sampling depths (see: upper_dept, and lower_depth columns). We can visualize the points using the plotKML package:
shape = http://maps.google.com/mapfiles/kml/pal2/icon18.png
kml(clay_total_sub, colour=value, shape=shape, points_names=clay_total_sub$value, balloon=TRUE)
KML file opened for writing...
Writing to KML...
A probably more accurate thing to do with this data is to visualize it as 3D points, which is possible by adding the 3rd dimension into the kml function:
clay_total_sub$depth <- clay_total_sub$upper_dept + (clay_total_sub$lower_dept - clay_total_sub$upper_dept)/2
kml(clay_total_sub, file="clay_total_sub3D.kml", colour=value, shape=shape, points_names=clay_total_sub$value, balloon=TRUE, altitude=300-depth)
KML file opened for writing...
Writing to KML...
To further explore possibilities of processing and visualizing soil profile data, consider using the aqp package, which will allow you to produce soil depth plots such as the one shown in this gallery.
The above tutorial, with illustrations, is also available as PDF.