How to set Predation?

EFDC_Explorer
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Why there isn’t Cyanobacteria and Greens algae in the temperature Options of Water Quality Modular part? It just have diatoms?Lower Optimal Temperature for Predation, Diatoms (degC):Upper Optimal Temperature for Predation, Diatoms (degC):Suboptimal Temperature Effect Coeff for Predation, Diatoms:Superoptimal Temperature Effect Coeff for Predation, diatoms:How to set predation?Thank you very much!

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Hi binlichen,

binlichen wrote: Why there isn’t Cyanobacteria and Greens algae in the temperature Options of Water Quality Modular part?
you can set those paras in WW model at Algae/temperature as seen in this below figure.
binlichen wrote: How to set predation?
The present model does not include zooplankton. Instead, a constant rate can be specified for algal predation, which implicitly assumes zooplankton biomass is a constant fraction of algal biomass. lternately, the predation rate can be taken as proportional to the algae biomass. Using a temperature effect similar to that for metabolism, the predation rate is given. The difference between predation and basal metabolism lies in the distribution of the end products of the two processes. In predation, Algalmatter (carbon, nitrogen, phosphorus, and silica) is returned to organic and inorganic pools in the environment, mainly to particulate organic matter. It is also noted that predation in the EFDC water quality model follows the original formulation in CE-QUAL-ICM (Cerco and Cole, 1995) which uses a predation rate constant with total predation loss being proportional to algae concentration. Subsequent CE-QUAL-ICM documentation, Cerco et al., (2000), appear to define predation independent of algae concentration.

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Dears
In the WW model at Algae/temperature
Just have Temperature Effect Coeff for Predation diatom,
where are the Temperature Effect Coeff for Predation Cyanobacteria and Greens algae?
Libin Chen
2013/06/21

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Hi Libin, thank you for your question.

You are correct that while the EE form “Algal Growth Temperature Constants” lists sub & super optimal temperature effect coefficients for predation for diatoms there are none listed for cyanobacteria, greens or macroalgae. This is because the EFDC code currently does not include this effect. However, the EFDC WQ theory manual does include a description of temperature adjusted predation rate. We will look to address this issue in a later release of EE. Mostly likely EE7.2.