Question:
Leaf area increases with stand age, resulting in a decreasing rate of photosynthesis in the stand.
Response:
An increment in leaf area increases also the photosynthesis of a tree stand. However, the relationship is saturating.
To transform atmospheric CO2 into organic molecules, plants can use the energy from
atmospheric oxygen.
sun light.
soil nutrients.
soil heat.
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
air temperature (T).
soil moisture (REW).
photosynthetically active solar radiation (PAR).
atmospheric CO2.
air humidity (VPD).
the total leaf area (LAI).
Carbon capture is performed by the green parts of plants via photosynthesis.
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.
In general, the more carbon dioxide that is available to the plant, the faster the rate of photosynthesis - if other factors are favourable.
In some part of the stems, some photosynthesis may also occur.
When there is low soil moisture, plants close its stomata pores which then decreases photosynthesis.
As plants respire, they release
carbon dioxide.
oxygen.
Transpiration decreases as air becomes drier.
Plants open its stomata to avoid losing too much water.
Plant closes its stomata to avoid losing too much water.
Photoinhibition means the decrease in photosynthesis due to
exposure to shortage of soil moisture.
exposure to excess of CO2.
exposure to high temperature.
exposure to excess of light.
exposure to excess of light
exposure to excess of CO2
exposure to high temperature
exposure to shortage of soil moisture
De-hardening in spring involves gradual re-hydration of the cells, recovery of photosynthetic capacity and a tight control of water loss.
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.