FAIR EU soil vocabularies: an overview of joint efforts from some EU Soil Mission projects

Vocabularies or thesauri, lists of terms with their definitions and unique ID, like a dictionary of a language, play a critical role in the domain of soil science, providing a standardized framework for accurately documenting and communicating soil characteristics. In soil science, the use of precise and consistent terminology ensures the effective exchange of data, promoting interoperability among researchers, practitioners, and decision-makers. A well-structured vocabulary, part of soil classification or soil description standards, facilitates the classification of soil properties, such as texture, structure, fertility, and organic content, allowing combining data from different sources but described in a similar way. And thereby enabling reliable comparison and interpretation across different regions and time periods. Furthermore, these vocabularies enable and support the development of standardized databases, soil datasets and soil monitoring systems, which are essential for environmental management, land use planning, and agricultural practices. Inaccurate or ambiguous soil descriptions can lead to misinformed decisions, making the establishment of clear, universally accepted vocabularies crucial for advancing soil science, conservation efforts, and sustainable land management practices. Such practices would greatly enhance the FAIRness of the data being managed, ensuring data conservation over time.

Soil vocabularies come from many sources, some national or regional, some from international organizations such as the Food and Agriculture Organization of the United Nations (FAO) or the International Union of Soil Sciences (IUSS), e.g. World Reference Base for Soil Resources (WRB) or FAO Guidelines on Soil Description. Several initiatives worked on the identification and provision of agreed vocabularies in order to ensure the interoperability of their results at different scales (national, EU, international). This includes work by standard setting organizations (eg. ISO TC190), legislation (eg. EU INSPIRE Directive) and of course numerous collaborative projects, such as SIEUSOIL, EJP SOIL, ISLANDR, SoilWise, SPADES, Soil Mission Support and MARVIC. At present, many existing vocabularies have not been exposed in a referenceable and machine-readable manner, and instead remain “trapped” within PDF documents. Extracting the relevant concepts and exposing them in both human and machine readable forms on persistent URIs would be a valuable step towards soil data harmonization.

The European Mission: A Soil Deal for Europe, with currently about 50 research projects and a network of 100 living-labs and lighthouses, offers an interesting environment and opportunity for the co-creation of a harmonised framework for soil vocabulary description. Due to the diversity of Soil Mission Projects, gaps in existing vocabularies can be identified and experience can be gained in how to best present vocabularies for both data annotation as well as data discovery.

In this presentation we will share the current status on this topic, offering a non-exhaustive yet hopefully informative overview on existing materials (vocabularies and associated technologies to share them), on-going work and key challenges for achieving better soil data interoperability.

This study was made possible through funding from the EU's Horizon Europe program, specifically the ISLANDR and SoilWise projects.