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National Agricultural Library Thesaurus Concept Space

2024 NALT Concept Space

Redesigned for the machine age as part of the Library's "NALT for the Machine Age" initiative, NALT 2024 is a state-of-the-art multischeme concept space with added structural features for enhanced scalability and machine readability.

2022 Inaugural Schemes

  • "NALT Core", a trim NALT sub-scheme with just 14,196 frequently used agricultural concepts including 4,396 agriculturally important organisms (taxa), and structural updates (see below) for a lean and efficient machine readable agricultural knowledge base.
  • "NALT Full", all NALT concepts - NALT Core plus over 48,000 additional agricultural related organisms (taxa) and several thousand less frequently used concepts for a total of 77,093 concepts. NALT Full is  a more granular knowledge base.

2023 Schemes

  • "NALT AWIC", 881 Animal Welfare concepts curated by NAL's Animal Welfare Information Center (AWIC) staff.
  • "NALT Taxon", 52,978 organisms (taxa) names important to agriculture.

      Note: The 2023 schemes will be available for online search in 2024. 
      Stay tuned for more sub-schemes in 2024!

New NALT Structural Features

  • Streamlined top concepts reflect USDA programs and services to support data linkages, transparency, and enhance agriculture research and information discoverability.
    •   Animals, Livestock, One Health
    •   Economics, Trade, Law, Business, Industry
    •   Farms, Agricultural Production Systems
    •   Fields of Study
    •   Forestry, Wildland Management
    •   Geographical Locations
    •   Human Nutrition, Food Safety and Quality
    •   Natural Resources, Conservation, Environment
    •   Plant Production, Gardening
    •   Research, Technology, Methods
    •   Rural Development, Communities, Education, Extension
    •   Taxonomic Hierarchy
  • Maintained natively as linked data graph, also known as knowledge graph (SKOS concept scheme).
  • Knowledge graph enables linked open data mappings across the internet, harnessing the power of the semantic web.
  • Mapping to other resources  - Library of Congress Subject Headings, CAB Thesaurus, AGROVOC, Global Agricultural Concept Space (GACS), and Wikidata. NALT 2022 mappings have increased since last year by 70% to 50,275.
  • NALT persistent uniform resource identifiers (URIs) are upgraded to HTTPS (Hypertext Transfer Protocol Secure), ensuring secure access to NALT concept descriptions. Legacy HTTP NALT URIs are currently supported by redirects.
  • NALT concept types (Organism, Chemical, Product, Geographical, Topic) express the most salient features of the concept space.
  • Product-to-organism and the reverse relationships are added to capture deeper knowledge of agricultural production from farm to fork.
  • New backend workflows, protocols, and tools to add new sub-schemes, and for improved, routine validation, consistency, and quality checking.
  • The NAL project "NALT for the Machine Age"  along with interested agricultural subject matter expert communities, is working to create additional sub-schemes within the NALT concept space.