What is the source of carbon that is assimilated in photosynthesis?
Photosynthesis of a tree canopy is driven or influenced by
air temperature (T).
soil moisture (REW).
photosynthetically active solar radiation (PAR).
air humidity (VPD).
the total leaf area (LAI).
Early spring is a tricky time for plants due to the combination of sunny but still quite cold days.
High soil moisture leads to decreased photosynthesis.
In boreal upland forests, low soil moisture decreases the rate of photosynthesis.
Plant respiration captures CO2.
Unlike photosynhesis, plant respiration captures atmospheric oxygen and releases carbon dioxide.
Almost half of the total biomass of a tree may be allocated to the roots.
To transform atmospheric CO2 into organic molecules, plants can use the energy from
Carbon becomes locked as part of the accumulating plant biomass as plants grow.
A complex microbiota lives belowground, releasing carbon dioxide to the soil.
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.
exposure to excess of light
exposure to shortage of soil moisture
exposure to high temperature
exposure to excess of CO2
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.
When there is low soil moisture, plants close its stomata pores which then decreases photosynthesis.
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.
De-hardening in spring involves gradual re-hydration of the cells, recovery of photosynthetic capacity and a tight control of water loss.