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 air temperature.
the changes in soil temperature.
the changes in CO2 concentration.
Photosynthesis of a tree canopy is driven or influenced by
air humidity (VPD).
the total leaf area (LAI).
photosynthetically active solar radiation (PAR).
soil moisture (REW).
air temperature (T).
Carbon capture is performed by the green parts of plants via photosynthesis.
When there is low soil moisture, plants close its stomata pores which then decreases photosynthesis.
Carbon becomes locked as part of the accumulating plant biomass as plants grow.
High soil moisture leads to decreased photosynthesis.
In boreal upland forests, low soil moisture decreases the rate of photosynthesis.
Transpiration decreases as air becomes drier.
At low air humidity, a plant closes its stomata to prevent transpiration. The action also decreases photosynthesis
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.
To transform atmospheric CO2 into organic molecules, plants can use the energy from
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.
Photoinhibition means the decrease in photosynthesis due to
exposure to excess of light.
exposure to shortage of soil moisture.
exposure to high temperature.
exposure to excess of CO2.
Early spring is a tricky time for plants due to the combination of sunny but still quite cold days.
The rate of respiration decreases with temperature.