The annual cycle of photosynthesis mainly follows
the changes in soil temperature.
the changes in air temperature.
the changes in light.
the changes in CO2 concentration.
Early spring is a tricky time for plants due to the combination of sunny but still quite cold days.
When there is low soil moisture, plants close its stomata pores which then decreases photosynthesis.
High soil moisture leads to decreased photosynthesis.
In boreal upland forests, low soil moisture decreases the rate of photosynthesis.
Almost half of the total biomass of a tree may be allocated to the roots.
At low air humidity, a plant closes its stomata to prevent transpiration. The action also decreases photosynthesis
Photosynthesis of a tree canopy is driven or influenced by
soil moisture (REW).
photosynthetically active solar radiation (PAR).
air temperature (T).
air humidity (VPD).
the total leaf area (LAI).
A complex microbiota lives belowground, releasing carbon dioxide to the soil.
Carbon becomes locked as part of the accumulating plant biomass as plants grow.
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.
What is the source of carbon that is assimilated in photosynthesis?
Plant respiration captures CO2.
Unlike photosynhesis, plant respiration captures atmospheric oxygen and releases carbon dioxide.
In some part of the stems, some photosynthesis may also occur.
Photoinhibition means the decrease in photosynthesis due to
exposure to shortage of soil moisture.
exposure to excess of light.
exposure to high temperature.
exposure to excess of CO2.
exposure to excess of light
exposure to excess of CO2
exposure to shortage of soil moisture
exposure to high temperature
The rate of respiration decreases with temperature.