Harmonized World Soil Database v2.0
The Harmonized World Soil Database version 2.0 (HWSD v2.0) is a comprehensive global soil inventory that offers detailed insights into soil properties, including their morphology, chemistry, and physical characteristics, with a focus on a 1 km resolution. It's a valuable tool for research in areas like agriculture, food security, and climate change impacts.
Developed in 2008 by the International Institute for Applied Systems Analysis (IIASA) and the Food and Agriculture Organization of the United Nations (FAO), the HWSD was a collaborative project involving other notable organizations like the International Soil Reference and Information Centre (ISRIC), the European Soil Bureau Network (ESBN), and the Institute for Soil Sciences at the Chinese Academy of Sciences (CAS). The data was compiled and organized using a Geographic Information System (GIS) at IIASA. This collaborative effort ensured that the database was comprehensive and accurate. Subsequent updates were made in 2013 (HWSD v1.2) and in 2023 (HWSD v2.0).
HWSD v2.0 expands on its previous versions by including data from various national soil databases, offering detailed soil attributes for seven different soil layers (a significant increase from the two layers in HWSD v1.2), and adopting a consistent soil reference system combining FAO1990 standards with the World Reference Base for Soil Resources.
In September 2023, a revised version of HWSD v2.0 was released. For detailed information on the updates in this version (v2.01), refer to the technical report below.
The HWSD v2.0 features a GIS raster image file that is connected to a soil attribute database. This database provides comprehensive information on the composition of soil units in nearly 30,000 soil mapping units. The HWSD v2.0 Viewer, included with the database, automatically establishes this link, allowing easy access to both the soil attribute data and mapping information.
Download : Download viewer & data (only soil types) | Download database (.mdb) | HWSD Raster v2.0 | Technical Report and Instructions
Changelog
- Soil data from ISRIC - WISE replaced with WISE30sec database data, increasing soil profiles from 10,250 to 21,000.
- WISE30sec uses a climatic co-variant based on Kӧppen-Geiger classification, replacing topsoil texture variant in original HWSD.
- HWSD v2.0 has seven depth layers: 0–20 cm, 20–40 cm, 40–60 cm, 60–80 cm, 80–100 cm, 100–150 cm, and 150–200 cm. Previous version had only two layers.
- Expanded soil attribute data in HWSD v2.0 includes effective CEC, total nitrogen, C/N ratio, and aluminum saturation.
- National soil databases from Afghanistan, Ghana, and Türkiye added, increasing soil mapping units from 16,327 to 29,538.
- HWSD v2.0 uses FAO 1990 Revised Legend for all soil units, correlated with World Reference Base for Soil Resources (2022).
- New land cover layer added for better identification of built-up areas, used for classifying Urbic Anthrosols and Technosols.
- Specific soil parameters updated: reference soil depth replaced by rootable soil depth; AWC recalculated; USDA textural class and Reference Bulk Density included for all depth layers.
- Soil phase information from Digital Soil Map of the World integrated, defining WRB Soil Reference Groups and Soil Units.
- HWSD viewer enhanced to handle expanded information in HWSD v2.0.
- Resolution of 1 km (30 arc-second) maintained.
- Error estimates and statistics for soil parameters available in WISE30sec database.