Photosynthesis of a tree canopy is driven or influenced by
photosynthetically active solar radiation (PAR).
soil moisture (REW).
the total leaf area (LAI).
air temperature (T).
air humidity (VPD).
Transpiration decreases as air becomes drier.
Early spring is a tricky time for plants due to the combination of sunny but still quite cold days.
When there is low soil moisture, plants close its stomata pores which then decreases photosynthesis.
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.
De-hardening in spring involves gradual re-hydration of the cells, recovery of photosynthetic capacity and a tight control of water loss.
In some part of the stems, some photosynthesis may also occur.
At low air humidity, a plant closes its stomata to prevent transpiration. The action also decreases photosynthesis
The annual cycle of photosynthesis mainly follows
the changes in light.
the changes in air temperature.
the changes in CO2 concentration.
the changes in soil temperature.
A complex microbiota lives belowground, releasing carbon dioxide to the soil.
As plants respire, they release
Photosynthesis releases oxygen whereas respiration releases CO2.
In general, the more carbon dioxide that is available to the plant, the faster the rate of photosynthesis - if other factors are favourable.
Leaf area increases with stand age, resulting in a decreasing rate of photosynthesis in the stand.
An increment in leaf area increases also the photosynthesis of a tree stand. However, the relationship is saturating.
Photoinhibition means the decrease in photosynthesis due to
exposure to excess of CO2.
exposure to excess of light.
exposure to high temperature.
exposure to shortage of soil moisture.
exposure to excess of light
exposure to excess of CO2
exposure to high temperature
exposure to shortage of soil moisture
Carbon capture is performed by the green parts of plants via photosynthesis.