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