This soil type data set we are referring to here is based on the HWSD. "The Land Use Change and Agricultural Program" (LUC) of the "International Institute for Applied System Analysis" (IIASA) and the "Food and Agrigultural Organization of the United Nations" (FAO) have developed a new substantial "Harmonized World Soil Database" (HWSD). It refers to a 30 arc-sec raster database which presents the global soil classes and their occurrence and distribution on the earthʻs surface.
The project was carried out in partnership with:
- the "International Soil Reference and Information Centre" (ISRIC) and its "World Soil Information". Together with the FAO, they were responsible for the development of regional soil and terrain databases and the WISE soil profile database;
- the European Soil Bureau Network, which had recently completed a major update of soil information for Europe and northern Eurasia, and
- the Institute of Soil Science, Chinese Academy of Science, which provide the recent 1:1,000,000 scale Soil Map of China
For version 1.0 of the HWSD, four source-databases have been used: The European Soil Database (ESDB), the 1:1,000,000 Soil Map of China, various regional SOTER Databases (SOTWIS Database) and the FAO-UNESCO Soil Map of the World.
The raster database contains more than 15000 different soil mapping units and combines existing regional and national updates of soil information worldwide (SOTER, ESD, Soil Map of China, WISE) with the information within the 1:5,000,000 scale FAO-UNESCO "Soil Map of the World" (FAO, 19711981).
The resulting database consists of 21600 rows and 43200 columns, which are linked to harmonized soil property data. This standardised texture allows the linkage of attribute data to the raster data to display or query certain soil units and their parameters.
The soil unit symbols refer to the "World Reference Base of Soil Resources" (WRB), the classification system that was developed in the context of the "Soil Map of the World".