Transpiration decreases as air becomes drier.
In some part of the stems, some photosynthesis may also occur.
To transform atmospheric CO2 into organic molecules, plants can use the energy from
In general, the more carbon dioxide that is available to the plant, the faster the rate of photosynthesis - if other factors are favourable.
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.
Plant respiration captures CO2.
Unlike photosynhesis, plant respiration captures atmospheric oxygen and releases carbon dioxide.
When there is low soil moisture, plants close its stomata pores which then decreases photosynthesis.
A complex microbiota lives belowground, releasing carbon dioxide to the soil.
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 becomes locked as part of the accumulating plant biomass as plants grow.
What is the source of carbon that is assimilated in photosynthesis?
At low air humidity, a plant closes its stomata to prevent transpiration. The action also 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.
Photosynthesis of a tree canopy is driven or influenced by
air temperature (T).
soil moisture (REW).
the total leaf area (LAI).
photosynthetically active solar radiation (PAR).
air humidity (VPD).