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Task ID:  6178  Make remobilised N be used in the same day    
Created by rcichota on 2016-09-16 10:20 AM, 523 days ago
Project:  Module Code
Category:  Minor
Priority:  [no priority]
Assigned to:  [not assigned]  
Status:  closed
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Your Name:Rogerio
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 comment 42456 posted by rcichota on 2016-09-16 10:20 AM, 523 days ago 

In AgPasture part of N is each tissue is made available to be used in new growth upon tissue senescence. Currently this is computed at the end of the day and the N amount remobilised can utilised on the following day. This approach makes neecessary to track N and DM for all species over two days (current and previous day). Moving the calculation of tissue turnover to the beggining of the day enables to use the remobilised N in the same day and eliminates the need to keep track of previous day N and DM, making the code clearer. This has repercussions in growth (as N remobilised is available in the same day) but also on surfaceOM as return is on a different day, potentially with a different N content...

In parallel, AgPasture returned to SurfaceOM any N remobilised that was not used on a given day. This is not quite correct, as the N should be added to the dead pool, and detached slower. Because of the current approach the N content of dead pool never varies, which is not true, especially in situation of plant dying due to drought, frost etc.

The change being implemented places the turnover calculation at the beginning of the day, computing a remobilisable amount, this can be used in the same day, if not it is added to the dead pool. All instances of previous day N and DM are deleted