Yes, i found many interesting info in acuaria webs, wich i used in the sheet.
Its difficult to know what wavelenghts plants need. Now im experimenting with leds, trying to know more (by trial/error). Are green light necessary? Although isnt strictly necessary, it improve yield? Same cuestion for far red light. Inavoidable for long day flowering plants, its necessary for a short day specie like cannabis?Improve yield?What percentages of each wavelenght are the best?
Until these questions will be answered, a reasonable choice is give plants all the spectrum, but putting emphasis in red light, with the higher photosyntesis promotion capacity, and provide enough blue light to ensure a health grow.
How much blue light is needed? Ive seen botany studies wich suggest there is absolute needings of blue light, rather than a percentage of irradiance. 35-40 microE/sec of blue light seems to be enough, and mantain internodal distances short (because of that, i included the total blue output in the sheet).
The good thing about the sheet (sure it can be improved with more people working in it) is we have a tool to know what are we giving to our plants, and we can compare with more knowledge.
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b. You need an average of 200-250 PUR/m2 for ... intensity(?)
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PUR is a measure of PAR (in microE), corrected by absorbance and photosyntesis action spectrum. A little more accurate than only PPF (PAR in microE). And far more informative than lm or Watts. The main objetive is give up those ambiguous units. Lm isnt accurate because depend of SPD, and only is valid when talking about same or very similar SPDs. Watts isnt a good unit because depend of the bulbs eff (u need 800w of 20w CFLs to put the same microE than a 400w HPS).
PUR is the unit we must know properly. For reference, i use the standars we use usually: a 400w HPS per m2 is the min recomended. The 400w HPS bulbs rated are from 400 to 500 PUR. So, i take 400PUR as the min recomended per m2 in flowering, and the 400-800 range as the recomended. Depending of how much grow we want in veg, i take the 150-300PUR in veg (200-250 average).
PS: when no specified, units references are per sq meter