NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Characterizing photosynthesis and transpiration of plant communities in controlled environmentsCO2 and water vapor fluxes of hydroponically grown wheat and soybean canopies were measured continuously in several environments with an open gas exchange system. Canopy CO2 fluxes reflect the photosynthetic efficiency of a plant community, and provide a record of plant growth and health. There were significant diurnal fluctuations in root and shoot CO2 fluxes, and in shoot water vapor fluxes. Canopy stomatal conductance (Gc) to water vapor was calculated from simultaneous measurements of canopy temperature (Tcan) and transpiration rates (Tr). Tr in the dark was substantial, and there were large diurnal fluctuations in both Gc and Tr. Canopy net Photosynthesis (Pnet), Tr, and Gc increased with increasing net radiation. Gc increased with Tr, suggesting that the stomata of plants in controlled environments (CEs) behave differently from field-grown plants. A transpiration model based on measurements of Gc was developed for CEs. The model accurately predicted Tr from a soybean canopy.
Document ID
20040089206
Acquisition Source
Ames Research Center
Document Type
Reprint (Version printed in journal)
Authors
Monje, O.
(Utah State University Logan 84322-4820, United States)
Bugbee, B.
Date Acquired
August 21, 2013
Publication Date
December 1, 1996
Publication Information
Publication: Acta horticulturae
Volume: 440
ISSN: 0567-7572
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: NCC2-139
Distribution Limits
Public
Copyright
Other
Keywords
NASA Discipline Life Support Systems
Non-NASA Center

Available Downloads

There are no available downloads for this record.
No Preview Available