A new canopy photosynthesis and transpiration measurement system (CAPTS) for canopy gas exchange research

• This paper reports the design of a new automatic canopy photosynthesis and transpiration measurement system (CAPTS).
• The CAPTS provides an accurate measurements of canopy photosynthetic CO2 uptake rate.
• The CAPTS can also be used to measure canopy respiration, soil respiration, root respiration and spike photosynthesis.
• The CAPTS provides a timely tool to quantify canopy light and water use efficiency to support crop engineering and breeding.

Accurate measurement of canopy gas exchange rates is crucial for studying canopy photosynthetic resource use efficiencies. We designed, created, and evaluated a new canopy photosynthesis and transpiration measurement system (CAPTS). The CAPTS included: (1) modular chamber sides, (2) sensors for temperature, CO2, air pressure and humidity that were integrated on a removable chamber cover, and (3) a user-friendly console for control of automatic opening and closing of the chamber cover for data recording, storage and analysis. The CAPTS can accurately measure canopy photosynthetic CO2 uptake rate, which was demonstrated with both rice and tobacco. The CAPTS provides a basic ability to measure rates of photosynthesis, respiration, and transpiration of plot-size canopies and other components of agro-ecosystems.

Figure optionsDownload as PowerPoint slide