|MadSci Network: Environment & Ecology|
Normally plants should absorb CO2 and release O2 during photosynthesis, however,there are some factors that influence photosynthesis, such as humudity(low humidity will limit photosynthesis), temperature(high temperature promotes photorespiration, which is competitive with photosynthesis for resources, releases CO2 and ammonium) , light intensity. Plants also do respiration throughout its lifetime, which absorbs O2 and release CO2. Humidity and tempetature also will influence respiration rate. In your system, somehow the plant did more respiration than photosynthesis, which means this system is stressful for this plant. Reason for the stress is hard to speculate, but plants need some time to adapt to the new environment, so the CO2 level may increase during the first day and may decrease after several days. Reference: 1. http://unisci.com/stories/20013/0831012.htm 2. Salisbury and Ross (1997), Plant Physiology, 4th edition; Taiz & Zeiger (1998), Plant Physiology 2nd edition
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