Affect of Different Colored Lights on Photosynthesis
PUR cannot be dismissed as some lighting experts have attempted to do based on their short time in the professional aquarium keeping industry, as we have already clearly established (as per the Overview section) that we found that once more precisely tuned spectrum fluorescent lights became available, we could grow aquarium plants more efficiently and with some advancements, this made the difference of not keeping photosynthetic marine organisms at all!! I should note that some of these advancements were comparing apples to apples; T12 to T12 such as a warm white to a Trichromatic or an actinic (which rules out lumens per watt and other measurements and leaves the FACT of PUR).
Effect of Different Colored Lights on Photosynthesis
PUR (Photosynthetically Usable Radiation) is something aquarium keepers should concern themselves with along with PAR in providing correct lighting since it describes the quality of light photons as per application.
Another term is . I should point out that while the terms PAS & PUR have a lot in common, there is a difference in that PAS is most simply stated as the spectrum where "chlorophyll is much more efficient at using the red & blue spectrums of light to carry out photosynthesis. Therefore, the action spectrum graph would show spikes above the wavelengths representing the colors red & blue."
Biology - How Light Intensity Affects the Rate of Photosynthesis
*Photosynthetic response; During this time, the molecules needed for photosynthesis gradually reach operating levels which begins when energy from light is absorbed by proteins called photosynthetic reaction centers that contain chlorophylls.
light intensity on photosynthesis ..
The Daily Light Integral is the total amount of light (or Photosynthetic Photon Flux Density, or PPFD) falling on a given area during the entire photoperiod. The best comparison is to compare PPFD to rainfall. An instantaneous PPFD value (the number of photons falling on a given surface area in a given amount of time) is equivalent to the number of raindrops falling on an equal area and time. We would find a weather report presenting rainfall as number of raindrops falling on a square meter per second to be practically useless. We are more interested in the total amount of rainfall reported in inches or centimeters. The same is true for light - we should be interested in the total number of photons in a given photoperiod.
photosynthesis light intensity.
Many natural waters contain at least some phytoplankton (algae, diatoms, etc.) The photopigments within these organisms absorb various light wavelengths to power photosynthesis, thus altering the optical quality of the water. In extreme cases, the water may appear green (algae) or brown (diatoms) due to absorption and reflectance of light.
Effects of light intensity on the growth and ..
*Phototropic response; having a tendency to move in response to light. Basically this is the Chlorophyll containing plant or algae "moving" to respond to a positive light source to begin the process of photosynthesis (initial growth of plants, zooxanthellae, etc.).
Read "Effects of light intensity on the ..
Many people will think PUR is good in theory, but think it cannot be applied to every single species we are trying to grow under water. While we don't know every species and it's preferred nm of light prefers, we do know the light, which triggers photosynthesis in an organism as well as efficiencies based on real world tests.