The rate of respiration decreases with temperature.
Photosynthesis of a tree canopy is driven or influenced by
photosynthetically active solar radiation (PAR).
soil moisture (REW).
the total leaf area (LAI).
air temperature (T).
air humidity (VPD).
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.
Almost half of the total biomass of a tree may be allocated to the roots.
Carbon becomes locked as part of the accumulating plant biomass as plants grow.
In general, the more carbon dioxide that is available to the plant, the faster the rate of photosynthesis - if other factors are favourable.
Plants open its stomata to avoid losing too much water.
Plant closes its stomata to avoid losing too much water.
What is the source of carbon that is assimilated in photosynthesis?
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.
De-hardening in spring involves gradual re-hydration of the cells, recovery of photosynthetic capacity and a tight control of water loss.
Transpiration decreases as air becomes drier.
Early spring is a tricky time for plants due to the combination of sunny but still quite cold days.
In some part of the stems, some photosynthesis may also occur.
High soil moisture leads to decreased photosynthesis.
In boreal upland forests, low soil moisture decreases the rate of photosynthesis.