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NAL Agricultural Thesaurus
U.S. Department of Agriculture

National Agricultural Library Thesaurus Concept Space

2023 NALT Concept Space

Redesigned for the machine age as part of the Library's "NALT for the Machine Age" initiative, NALT 2023 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 subscheme with just 13,791 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 76,933 concepts. NALT Full is  a more granular knowledge base.

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 subschemes, 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 subschemes within the NALT concept space.

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