Effect of light intensity and nutrient concentration on the bioluminescence of dinoflagellates

[n1234]

Hi, I'm working on a science fair project about the effect of light intensity and nutrient concentration on the bioluminescence of dinoflagellates. For my project I had three groups of dinoflagellates and they were all exposed to varying light intensity and nutrient concentration. Group 1 - 100 photons, 2.5 micromoles per liter, the avg bioluminescence was 1089.9 lx. Group 2 - 150 photons, 0.5 micromoles per liter, the avg bioluminescence was 2074.5 lx. Group 3 - 50 photons, 5 micromoles per liter, the avg bioluminescence was 497 lx. I used a digital lux meter to measure the bioluminescence and I think it may have been broken, so I was wondering if you could please tell me if the values are too high. Also I used Pyrocystis fusiformis species of dinoflagellates, a fluorescent light source and the average was from a period of 10 days for each group.

[Sofiaherron12]

Hello! According to a similar experiment done by Fiona Bell, it seems like your results are normal in terms of the common lx of dinoflagellates. However, this doesn't mean that your meter works. It could still be broken, just not enough to raise too much suspicion. Paul Schlyter has data showing that an overcast day is about 1000 lx. If that makes sense with the intensity of the light you saw from Group 1, then it might be ok. To be sure, I suggest you test your lux meter. There are some articles online on how to do this. If you have a smart phone, you can download a meter app to compare data. On apple, there is one called Photo Light & Exposure Meter.

Fiona Bell's experiment: https://www.researchgate.net/publicatio ... _Algae#pf5

Paul Schlyter's data: http://stjarnhimlen.se/comp/radfaq.html#10

Hope this helps, let me know if you have any other questions, or if I misunderstood anything.

[Turapter]

To validate the accuracy of your lux meter, it would be ideal to compare its readings with a known standard or reference. This can help ensure that the measurements are reliable and consistent. If you have access to a calibrated lux meter or if you can consult with a science teacher or mentor, they may be able to provide guidance on verifying the accuracy of your measurements.