nitrogen chain

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iaelr
Posts: 14
Joined: Tue Aug 12, 2014 1:52 pm
Location: USA

nitrogen chain

Post by iaelr » Wed Mar 13, 2019 3:43 am

Hi!

I would like to simulate a nitrogen chain with two sources of ammonium (one from organic matter and one from Urea fertilizer) and then ammonium nitrification into nitrate. So 4 solutes, 1 and 2 with first order reactions to solute 3 and solute 3 with first order reaction to solute 4.
Is it possible? How should I define it?

Thank you for the help,
iael

Jirka
Posts: 4712
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: nitrogen chain

Post by Jirka » Thu Mar 14, 2019 12:21 am

The standard HYDRUS code allows only one parent compound for a daughter product. If you want to have two parent compounds, you would need to use for one of them a zero-order reaction of the daughter compound (e.g., for mineralization of organic matter, as has been done in several HYDRUS applications for nitrogen systems). You can obviously accomplish that using HP2, where you can define any relationships between parent and daughter products. J.

iaelr
Posts: 14
Joined: Tue Aug 12, 2014 1:52 pm
Location: USA

Re: nitrogen chain

Post by iaelr » Thu Mar 14, 2019 10:03 pm

Thank you!

iaelr
Posts: 14
Joined: Tue Aug 12, 2014 1:52 pm
Location: USA

Re: nitrogen chain

Post by iaelr » Thu Jun 27, 2019 8:46 pm

A follow up question:

I am now simulating a first order nitrification chain (urea-amonium-nitrate). As well as zero order mineralization in a specific layer that generates ammonium.
Where in the output files I can see how much ammonium is being generated from urea through the first order reaction and how much from the zero order reaction?
I see it now all together in the CumCh0 column in solute2.out and was wondering if there is a way of separating them?

Thank you,
iael

Jirka
Posts: 4712
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: nitrogen chain

Post by Jirka » Thu Jun 27, 2019 9:05 pm

The Solute_i.out files give you all boundary solute fluxes, as well as cumulative zero- and first-order reaction fluxes. If you have three species (urea-amonium-nitrate), then the first-order reaction of Urea should be the same as zero-order reaction for ammonium (if you do not have any other zero-order reactions for ammonium). If you do, then you can simply subtract from the total zero-order reaction for ammonium the first-order reaction for urea, to separate this additional zero-order reaction. J.

iaelr
Posts: 14
Joined: Tue Aug 12, 2014 1:52 pm
Location: USA

Re: nitrogen chain

Post by iaelr » Thu Jun 27, 2019 11:19 pm

Great, Thank you!

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