The annual cycle of photosynthesis mainly follows
the changes in light.
the changes in soil temperature.
the changes in CO2 concentration.
the changes in air temperature.
Photoinhibition means the decrease in photosynthesis due to
exposure to excess of light.
exposure to high temperature.
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).
air temperature (T).
air humidity (VPD).
photosynthetically active solar radiation (PAR).
soil moisture (REW).
The rate of respiration decreases with temperature.
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.
Carbon capture is performed by the green parts of plants via photosynthesis.
As plants respire, they release
Almost half of the total biomass of a tree may be allocated to the roots.
High soil moisture leads to decreased photosynthesis.
In boreal upland forests, low soil moisture decreases the rate of photosynthesis.
Carbon becomes locked as part of the accumulating plant biomass as plants grow.
What is the source of carbon that is assimilated in photosynthesis?
A complex microbiota lives belowground, releasing carbon dioxide to the soil.
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.
When there is low soil moisture, plants close its stomata pores which then decreases photosynthesis.
De-hardening in spring involves gradual re-hydration of the cells, recovery of photosynthetic capacity and a tight control of water loss.