Modelling the effect of diffuse light on canopy photosynthesis in controlled environments.

Item request has been placed! ×
Item request cannot be made. ×
loading   Processing Request
Read More Add to Saved list
  • Additional Information
    • Source:
      Publisher: International Society for Horticultural Science Country of Publication: Netherlands NLM ID: 100955313 Publication Model: Print Cited Medium: Print ISSN: 0567-7572 (Print) Linking ISSN: 05677572 NLM ISO Abbreviation: Acta Hortic
    • Publication Information:
      Original Publication: The Hague, International Society for Horticultural Science.
    • Subject Terms:
      Computer Simulation* ; Environment, Controlled* ; Light* ; Models, Biological*; Photosynthesis/*radiation effects ; Plant Physiological Phenomena/*radiation effects; Ecological Systems, Closed ; Hydroponics ; Life Support Systems ; Plant Leaves/growth & development ; Plant Leaves/metabolism ; Plant Leaves/radiation effects ; Triticum/growth & development ; Triticum/metabolism ; Triticum/radiation effects
    • Abstract:
      A layered canopy model was used to analyze the effects of diffuse light on canopy gross photosynthesis in controlled environment plant growth chambers, where, in contrast to the field, highly diffuse light can occur at high irradiance. The model suggests that high diffuse light fractions (approximately 0.7) and irradiance (1400 micromoles m-2 s-1) may enhance crop life-cycle canopy gross photosynthesis for hydroponic wheat by about 20% compared to direct light at the same irradiance. Our simulations suggest that high accuracy is not needed in specifying diffuse light fractions in chambers between approximately 0.7 and 1, because simulated photosynthesis for closed canopies plateau in this range. We also examined the effect of leaf angle distribution on canopy photosynthesis under growth chamber conditions, as these distributions determine canopy extinction coefficients for direct and diffuse light. We show that the spherical leaf angle distribution is not suitable for modeling photosynthesis of planophile canopies (e.g., soybean and peanut) in growth chambers. Also, the absorption of the light reflected from the surface below the canopy should generally be included in model simulations, as the corresponding albedo values in the photosynthetically active range may be quite high in growth chambers (e.g., approximately 0.5). In addition to the modeling implications, our results suggest that diffuse light conditions should be considered when drawing conclusions from experiments in controlled environments.
    • Contributed Indexing:
      Indexing Agency: NASA Local ID #: 00029552.
      Investigator: HW Janes, Rutgers U, New Brunswick, NJ
      Keywords: NASA Discipline Life Support Systems; Non-NASA Center
      Note: Grant numbers: NAGW-5003.
    • Publication Date:
      Date Created: 20030729 Date Completed: 20030818 Latest Revision: 20191107
    • Publication Date:
      20240829
    • Accession Number:
      10.17660/actahortic.2002.593.4
    • Accession Number:
      12882223