About soil data

Web based soil map of Kenya

ISRIC develops new web-based digital soil maps, for scientists, policy makers and land users

Towards digital soil maps

Since 1900, thousands of soil maps have been made by institutes in over 100 countries. Unfortunately, these maps are not always user friendly. Some are unavailable, others incomplete or out of date, and it is cumbersome to do computer-based analyses of the underlying data to predict soil properties. What’s more, the current maps only cover one third of the Earth’s ice-free land surface with very different information. So there is a need for improved soil maps and soil data systems. ISRIC develops new web-based digital soil maps, for scientists, policy makers and land users.

Demand for soil data is growing

As planners and land users increasingly recognize the role that soils can play in combatting land degradation, biodiversity and climate regulation, demand for relevant soil information or usable soil data is soaring. Data needs to be made available on different scales: global level (scale 1:5 million; 5 km resolution), regional level, for instance for South-east Asia and Europe (scale 1:1 million; 1 km resolution), and national and local levels (scales 1:250 000 to 1: 50 000; resolution 250 - 50m).

Web-accessible digital soil maps provide soil information on different scales. These modern maps are not maps in the classical sense. Essentially, they are spatial databases of soil properties, compiled from continuous monitoring of soil and landscape characteristics, including through use of near and remote sensing techniques, manual input and web crawling. By using geo-statistical methods, models are developed by soil scientists to predict the soil properties in an area. These predictions contain uncertainty with respect to every location and may be more precise than they can obtained from qualitative assessments based on field sampling and laboratory analysis only.

To compile such soil maps on regional and global scale, existing legacy data from around the world have to be collected, standardized and generalized. In addition, algorithms (so called Soil inference system) have to be developed to predict soil properties at these different scales. ISRIC’s primary responsibility is to collect and review soil samples and data from around the world, and to develop tools for collating soil data.

 

Choose a project:

Collecting representative soils for the FAO-UNESCO Soil Map of the World

Since 1964, ISRIC has been collecting soil samples from around the world, to create and maintain a world soil reference collection. The collection, initiated by FAO and UNESCO, comprises over 1100 physical representatives of the mapping units of the FAO-UNESCO Soil Map of the World. A selection of soil samples – called monoliths – is on display in the WorldSoil Museum. The whole collection is documented in the ISRIC Soil Information System (ISIS). During the coming three years, ISRIC will renew its soil reference collection with some 200 profiles.

 

Developing standardized, colour coded soil maps

Many national organizations collect soil and terrain data . This is done at various scales and using different mapping units and methods. Unfortunately, there are many gaps, and the absence of worldwide standards for survey techniques and soil-sample analysis has created a range of incompatible so-called area-class soil maps. To combat this problem, the International Union of Soil Science (IUSS) started the SOTER (SOil and TERrain) program in the 1990s. ISRIC and its partners developed procedures and software to compile standardized area-class maps and associated databases. Like their predecessors, these new, standardized maps and databases are colour coded maps, based on the classical mapping units (area-classes) for soils, forests and other terrain properties. The methodology has already been used for soil and terrain databases of many regions at continental level (Latin America, Central, South and Eastern Africa) and at national level (including Argentina, Tunisia, Nepal, Jordan and China). ISRIC is now coordinating a methodology update through the  e-SOTER project. It is the European contribution to a global soil observation system under the GEOSS framework. Various SOTER products have been included in the Harmonized World Soil Database.

Developing a functional global soil map

In November 2008, the Bill & Melinda Gates foundation and the Alliance for a Green Revolution in Africa (AGRA) started to finance the soil mapping of Sub-Sahara Africa for an Africa Soil Information Service (AfSIS), freely available for scientists that model climate change, food production, carbon sequestration and the like, decision makers, land planners and other users. Partly due to the efforts of ISRIC, the International Union of Soil Scientists (IUSS) decided to use the proposed soil mapping methodology for a new digital soil map of the whole world named GlobalSoilMap.net. Instead of being based on the classical soil mapping units (area-classes, see above), this GlobalSoilMap consists of spatial information systems of functional soil properties such as pH, water storage and amount of soil organic matter – properties important for combating land degradation, climate mitigation, biodiversity and other ecosystem functions. ISRIC is one of the seven supporting institutes.