A complex microbiota lives belowground, releasing carbon dioxide to the soil.
High soil moisture leads to decreased photosynthesis.
In boreal upland forests, low soil moisture decreases the rate of photosynthesis.
What is the source of carbon that is assimilated in photosynthesis?
As plants respire, they release
The rate of respiration decreases with temperature.
In general, the more carbon dioxide that is available to the plant, the faster the rate of photosynthesis - if other factors are favourable.
In some part of the stems, some photosynthesis may also occur.
Photosynthesis of a tree canopy is driven or influenced by
air humidity (VPD).
air temperature (T).
soil moisture (REW).
the total leaf area (LAI).
photosynthetically active solar radiation (PAR).
Almost half of the total biomass of a tree may be allocated to the roots.
When there is low soil moisture, plants close its stomata pores which then decreases photosynthesis.
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.
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.
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.
To transform atmospheric CO2 into organic molecules, plants can use the energy from