At low air humidity, a plant closes its stomata to prevent transpiration. The action also decreases photosynthesis
De-hardening in spring involves gradual re-hydration of the cells, recovery of photosynthetic capacity and a tight control of water loss.
Plant respiration captures CO2.
Unlike photosynhesis, plant respiration captures atmospheric oxygen and releases carbon dioxide.
Transpiration decreases as air becomes drier.
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.
As plants respire, they release
The annual cycle of photosynthesis mainly follows
the changes in light.
the changes in soil temperature.
the changes in air temperature.
the changes in CO2 concentration.
To transform atmospheric CO2 into organic molecules, plants can use the energy from
Almost half of the total biomass of a tree may be allocated to the roots.
Photosynthesis of a tree canopy is driven or influenced by
soil moisture (REW).
air humidity (VPD).
the total leaf area (LAI).
photosynthetically active solar radiation (PAR).
air temperature (T).
In general, the more carbon dioxide that is available to the plant, the faster the rate of photosynthesis - if other factors are favourable.
A complex microbiota lives belowground, releasing carbon dioxide to the soil.
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.
What is the source of carbon that is assimilated in photosynthesis?