What is the source of carbon that is assimilated in 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).
the total leaf area (LAI).
air humidity (VPD).
soil moisture (REW).
photosynthetically active solar radiation (PAR).
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.
High soil moisture leads to decreased photosynthesis.
In boreal upland forests, low soil moisture decreases the rate of photosynthesis.
The annual cycle of photosynthesis mainly follows
the changes in CO2 concentration.
the changes in soil temperature.
the changes in air temperature.
the changes in light.
Early spring is a tricky time for plants due to the combination of sunny but still quite cold days.
Carbon capture is performed by the green parts of plants via photosynthesis.
The rate of respiration decreases with temperature.
At low air humidity, a plant closes its stomata to prevent transpiration. The action also decreases photosynthesis
A complex microbiota lives belowground, releasing carbon dioxide to the soil.
Plants open its stomata to avoid losing too much water.
Plant closes its stomata to avoid losing too much water.
In general, the more carbon dioxide that is available to the plant, the faster the rate of photosynthesis - if other factors are favourable.
Transpiration decreases as air becomes drier.
As plants respire, they release
Photosynthesis releases oxygen whereas respiration releases CO2.