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 excess of CO2.
exposure to shortage of soil moisture.
exposure to high temperature.
At low air humidity, a plant closes its stomata to prevent transpiration. The action also decreases photosynthesis
Plants open its stomata to avoid losing too much water.
Plant closes its stomata to avoid losing too much water.
Photosynthesis of a tree canopy is driven or influenced by
soil moisture (REW).
air temperature (T).
the total leaf area (LAI).
photosynthetically active solar radiation (PAR).
air humidity (VPD).
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.
The annual cycle of photosynthesis mainly follows
the changes in air temperature.
the changes in CO2 concentration.
the changes in light.
the changes in soil temperature.
Almost half of the total biomass of a tree may be allocated to the roots.
As plants respire, they release
Photosynthesis releases oxygen whereas respiration releases 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.
Plant respiration captures CO2.
Unlike photosynhesis, plant respiration captures atmospheric oxygen and releases carbon dioxide.
De-hardening in spring involves gradual re-hydration of the cells, recovery of photosynthetic capacity and a tight control of water loss.
To transform atmospheric CO2 into organic molecules, plants can use the energy from
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.