Post by Carl on Nov 2, 2018 15:27:26 GMT -5
I have updated the "Aquarium Lighting" article, in particular the section dealing with "Photoinhibition"
Here is an excerpt:
"This is another concept to consider that we do not know all the "mechanisms" that drive it.
Basically photoinhibition is the damage to the light harvesting reactions of the photosynthetic capacity of a vascular plant, algae, or cyanobacterium by excess light energy trapped by the chloroplast.
This process can occur in in all organisms capable of oxygenic photosynthesis. In both plants & cyanobacteria, blue light causes photoinhibition more efficiently than other wavelengths of visible light, although it has been demonstrated the red light can cause photoinhibition as well.
One of the implications for us as aquarium keepers is this process can often be the result of new light systems until our plants, photosynthetic corals, etc. adapt to the new light.
The other implication is while we may still see good growth of our plants or coral, we often are "over driving" light to where not only are you wasting input energy for unnecessary PAR number the growth is not as good as it could be. This is common now with many popular well marketed LEDS such as the SB Reef Light.
This graph demonstrates maximum photosynthesis in the zooxanthellae in this Porites stony coral was achieved at about 200 µmol·m²·sec. At 350 µmol·m²·sec the rate of photosynthesis was about that seen at 75 µmol·m²·sec!"
Carl
Here is an excerpt:
"This is another concept to consider that we do not know all the "mechanisms" that drive it.
Basically photoinhibition is the damage to the light harvesting reactions of the photosynthetic capacity of a vascular plant, algae, or cyanobacterium by excess light energy trapped by the chloroplast.
This process can occur in in all organisms capable of oxygenic photosynthesis. In both plants & cyanobacteria, blue light causes photoinhibition more efficiently than other wavelengths of visible light, although it has been demonstrated the red light can cause photoinhibition as well.
One of the implications for us as aquarium keepers is this process can often be the result of new light systems until our plants, photosynthetic corals, etc. adapt to the new light.
The other implication is while we may still see good growth of our plants or coral, we often are "over driving" light to where not only are you wasting input energy for unnecessary PAR number the growth is not as good as it could be. This is common now with many popular well marketed LEDS such as the SB Reef Light.
This graph demonstrates maximum photosynthesis in the zooxanthellae in this Porites stony coral was achieved at about 200 µmol·m²·sec. At 350 µmol·m²·sec the rate of photosynthesis was about that seen at 75 µmol·m²·sec!"
Carl
