What is the source of carbon that is assimilated in photosynthesis?
Almost half of the total biomass of a tree may be allocated to the roots.
The rate of respiration decreases with temperature.
De-hardening in spring involves gradual re-hydration of the cells, recovery of photosynthetic capacity and a tight control of water loss.
The effect of light on photosynthesis has a clear saturating pattern: more light results in more photosynthesis but eventually leaves cannot take full advantage of all the extra light.
Transpiration decreases as air becomes drier.
Plant respiration captures CO2.
Unlike photosynhesis, plant respiration captures atmospheric oxygen and releases carbon dioxide.
In general, the more carbon dioxide that is available to the plant, the faster the rate of photosynthesis - if other factors are favourable.
Photoinhibition means the decrease in photosynthesis due to
exposure to shortage of soil moisture.
exposure to excess of light.
exposure to excess of CO2.
exposure to high temperature.
exposure to high temperature
exposure to excess of light
exposure to excess of CO2
exposure to shortage of soil moisture
Photosynthesis of a tree canopy is driven or influenced by
the total leaf area (LAI).
soil moisture (REW).
air humidity (VPD).
photosynthetically active solar radiation (PAR).
air temperature (T).
The annual cycle of photosynthesis mainly follows
the changes in light.
the changes in CO2 concentration.
the changes in air temperature.
the changes in soil temperature.
At low air humidity, a plant closes its stomata to prevent transpiration. The action also decreases photosynthesis
Plants open its stomata to avoid losing too much water.
Plant closes its stomata to avoid losing too much water.
High soil moisture leads to decreased photosynthesis.
In boreal upland forests, low soil moisture decreases the rate of photosynthesis.
As plants respire, they release
Photosynthesis releases oxygen whereas respiration releases CO2.