The annual cycle of photosynthesis mainly follows
the changes in soil temperature.
the changes in air temperature.
the changes in CO2 concentration.
the changes in light.
Photoinhibition means the decrease in photosynthesis due to
exposure to excess of light.
exposure to excess of CO2.
exposure to high temperature.
exposure to shortage of soil moisture.
The rate of respiration decreases with temperature.
As plants respire, they release
Photosynthesis releases oxygen whereas respiration releases CO2.
A complex microbiota lives belowground, releasing carbon dioxide to the soil.
De-hardening in spring involves gradual re-hydration of the cells, recovery of photosynthetic capacity and a tight control of water loss.
Carbon becomes locked as part of the accumulating plant biomass as plants grow.
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
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.
In general, the more carbon dioxide that is available to the plant, the faster the rate of photosynthesis - if other factors are favourable.
To transform atmospheric CO2 into organic molecules, plants can use the energy from
Plant respiration captures CO2.
Unlike photosynhesis, plant respiration captures atmospheric oxygen and releases carbon dioxide.
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.
In some part of the stems, some photosynthesis may also occur.