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Converse explanation of the positive and negative of the potential soil mineral nitrogen pool between the published paper and CLM documentation

Xueli Huo

Member
Hi,

I am reading the 2.21 decomposition section in the latest version of CLM Technical Note here
The potential soil mineral nitrogen pool NF calculated in equation 2.21.11 is the same as that in Thornton and Rosenbloom, 2005 as here

However, the explanation of the positive and negative value of NF seems completely converse.

In Thornton and Rosenbloom's paper (2005),

A positive value for NFud indicates nitrogen mineralization and a negative value indicates potential nitrogen immobilization demand.

While in the latest version of CLM Technical Note and CLM5.0 Technical Note,

Negative values of NF_pot_min,u-d indicate that the decomposition flux results in a source of new mineral nitrogen, while positive values indicate that the potential decomposition flux results in a sink (demand) for mineral nitrogen.
To me (a non-native English speaker), this is the converse description. Maybe I am wrong.
I also checked the codes in SoilBiogeochemPotentialMod.F90 file, and the description there is the same as that in the Technical Note.

The "converse" description does raise the question in my mind, which one is right ? It matters because it will change my understanding of the process.

Could someone clarify it here ? Appreciate the help a lot.

Sincerely,
 

Xueli Huo

Member
No need of help. I understand it now. The descriptions between the paper and the Tech Note are consistent in expressing the same thing.
 
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