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NAL Agricultural Thesaurus
U.S. Department of Agriculture

Concept Breadcrumbs

Fields of Study > physics > electricity and magnetism > electromagnetic radiation > light > photosynthetically active radiation
Fields of Study > physics > optics > light > photosynthetically active radiation
Preferred Term:

photosynthetically active radiation

Definition:
That portion of the electromagnetic spectrum that is the energy source utilized for photosynthesis and generally coincides with the visible light spectrum (approximately 400-700 nm). PAR is characterized by the greater absorption of the blue light and red light wavelengths by pigments.
Concept Schemes:
NALT Core
Broader Concept:
light
Related Concepts:
Entry Terms:
  • photosynthetic active radiation
  • PAR (photosynthetically active radiation)
URI:
https://lod.nal.usda.gov/nalt/69904
Download this Concept:
RDF/XMLCreated 2006-05-05, last modified 2017-12-06
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