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BLOOM algae sedimentation velocities

Christophe Thiange, modified 4 Years ago.

BLOOM algae sedimentation velocities

Jedi Knight Posts: 125 Join Date: 11/15/12 Recent Posts
For anyone interested, here are some guidelines from Hans Los regarding the sedimentation velocities of algae in BLOOM:

In BLOOM.SPE the default sedimentation rates for BLOOM.SPE for fresh water phytoplankton are 0, while for marine phytoplankton they are in the order of 0.5 to 1.0 m per day. This is not because there is a fundamental difference between fresh water and marine algae, but because the net sedimentation rates are also depending on the depth. Since many shallow lakes exist in which sedimentation rates are low, we have therefore decided not to put a positive default into the bloom.spe. Instead the user who wants to include sedimentation of (fresh) water algae in a model application is advised to include the appropriate values as constants in the model input (either via the GUI or directly into the input file, whatever the user prefers).

With respect to the species groups, sedimentation rates should be highest for diatoms, moderate for green algae and flagellates and very small or zero for blue green algae. Nutrient limited types are less healthy compared to energy types so their sedimentation rates as a rule should be higher.

Typical values for a deep lake would be Diatoms-E = 1.0 m per day, Diatoms-P 1.5 m per day, Green-E = 0.5 per day, Greens-P/N = 1.0 per day, BlueGRN-E = 0, BluegrnN/P = 0 or perhaps 0.5