Algae simulation

Question

Hi everyone,
I have a question about algae simulations in AEM3D/CAEDYM.
If I exactly define the same parameters for all groups of phytoplanktons  in .BIO and .INT files, should I expect to get the same simulated concentration for these algae?
I get different results. As a test, I had two different runs: Run12 and Run13. In run 12, I simulated two groups of algae; CRYPT and DINOF, and in run 13, I simulated only one group; DINOF. 
Run 12 grows much more CRYPT than DINOF. How does the model differentiate the growth of these two algae species, while all .INT and .BIO parameters have been defined exactly the same?

Regards,
 

Answer 1

The dynamics of each algal group is dependent on the light and nutrient resources available.  If you add an additional group then this group will consume nutrients and will affect the extinction coefficient.   

The old WQ CAEDYM had some group specific parameterisations depending on the group number used.  The new WQ model does not do this but there will still be differences between two groups with the same parameters as the groups are solved sequentially so the 1st group will have first go at the nutrients each timestep.

Chris