Nitrate Cal.

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arifa...@gmail.com

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Apr 8, 2025, 2:57:54 PM4/8/25
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Hello, I wish everyone good work. My problem is, although I calibrated my work in good performance, I get a very absurd output when modeling nitrate load. I am attaching the pictures. I wonder what the problem is?
summary_flow_cal.JPG
parameter.JPG
no3_cal.JPG
flow_cal.JPG

omc...@gmail.com

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Apr 8, 2025, 3:13:47 PM4/8/25
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Hi,

I have some suggestions:

- Do a sequential calibration, first calibrate your flow (which you already did), then fix the flow parameters, and then only calibrate the nitrate load. Doing this secures that you are only modifying nitrate process.
- Add more nitrate related parameters. Check how SWAT modelates the nitrate load in the 2009 Theorical Manual. It gives you an idea on how it works.
- Do not expect good results for nitrate, as far as I now, it is really hard to calibrate some variables in SWAT. If you are calibrating on monthly time step, then you have more chances to get decent results. If you are doing it daily, then your chances decreases.

Regards,
Oscar

ARIF AYDIN

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Apr 9, 2025, 1:27:54 AM4/9/25
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Thank you for your answer. What you mean is, let me keep the parameter values I use for flow calibration constant and add a few new parameters related to nitrate, and continue the calibration by changing the ranges for the existing ones.

sincerely
Arif

omc...@gmail.com <omc...@gmail.com>, 8 Nis 2025 Sal, 22:13 tarihinde şunu yazdı:
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omc...@gmail.com

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Apr 9, 2025, 12:49:59 PM4/9/25
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Hi,

Basically yes!

Regards,
Oscar

ARIF AYDIN

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Apr 22, 2025, 2:09:19 PM4/22/25
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Hi,
dear Oscar
First of all, I hope you are well. I am Arif from Türkiye. We have written before. I have been working on modeling nitrate in my work for more than two years. I finally calibrated the flow but I can't calibrate the nitrate. I need a favor from you but I understand if you don't want to waste your time on someone you don't know. If I send you my swat cup project, can you check it and give me an idea? Thanks for all


Arif

omc...@gmail.com <omc...@gmail.com>, 9 Nis 2025 Çar, 19:50 tarihinde şunu yazdı:

omc...@gmail.com

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Apr 22, 2025, 8:55:52 PM4/22/25
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We can further discuss this by email, omc...@gmail.com
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