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NASA NTRS · 20040090386

Steady-state canopy gas exchange: system design and operation

Bugbee, B.
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Abstract

This paper describes the use of a commercial growth chamber for canopy photosynthesis, respiration, and transpiration measurements. The system was designed to measure transpiration via water vapor fluxes, and the importance of this measurement is discussed. Procedures for continuous measurement of root-zone respiration are described, and new data is presented to dispel myths about sources of water vapor interference in photosynthesis and in the measurement of CO2 by infrared gas analysis. Mitchell (1992) has described the fundamentals of various approaches to measuring photosynthesis. Because our system evolved from experience with other types of single-leaf and canopy gas-exchange systems, it is useful to review advantages and disadvantages of different systems as they apply to various research objectives.

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NASA Discipline Number 61-10NASA Discipline Life Support SystemsNASA Program CELSSNon-NASA CenterPlants/chemistry/growth & development/metabolismLife Support Systems/instrumentationCarbon Dioxide/analysis/metabolismPhotosynthesisOxygen ConsumptionPlant TranspirationSupport, U.S. Gov't, P.H.SWaterAir/analysisSupport, U.S. Gov't, Non-P.H.SSupport, Non-U.S. Gov'tEquipment Design

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Bugbee, B.. 1992-07-01. Steady-state canopy gas exchange: system design and operation. https://ntrs.nasa.gov/citations/20040090386

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