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help with chl. a

Mon, 05/14/2007 - 11:12pm — prasid23
Hi everyone, My observed data of chlorophyll a is in (mg/m3). i divided it by 67 and entered the resulting values in Vpr.npt. In the Cin_br1.npt file, i put all the algae values at 0.0. the model has only one branch, and only one algae group. chl.a and algae appears as follows in graph.npt ....................CNAME.................. CMULT CMIN CMAX CPLTC # Algae, g/m^3 1.0 -0.01 3.0 OFF 16 ...................CDNAME.................. CDMULT CDMIN CDMAX CDPLTC # Algal production, g/m^2/day 1.0 -1.0 5.0 OFF 12 Chlorophyll a, mg/m^3 1000.0 -1.0 10.0 OFF 13 Total algae, g/m^3 1.0 -1.0 1.0 OFF 14 the snp.opt shows very low values of total alage and algae1 (both in g/m^3). i am wondering if i had missed any unit conversion steps cause algae is not showing any growth and is very very low compared to the observed data. can anyone give me some help/suggestion on how to input the chl. a values?
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Water Quality
Wed, 05/16/2007 - 10:00am — Rob

I am not sure why you are dividing your chl a by 67, is this your Chl a to Algal biomass fraction. The Vpr file is only used for setting the initial conditions. If you have set up the Cin_br1.npt file to zero for algae over time then you have no new algae coming in and your population is therefore dependnent on what you set your initial conditions to in the vpr file. The graph.npt file only controls the array viewer output and the output formats and their precision. To control the actual dynamics of the agal population this must be done in the control file.