why fertilizer did not have impact on LAI in clm

[xiaoxiaokuishu]

Hi, all,

I run a perennail crop simulation with ctsm1, the model use below code to fertilized,
fert(p) = (manunitro(ivt(p)) * 1000._r8 + fertnitro(p))/ fert_counter(p)
use_flexiblecn = .true.
use_fun = .true.

I only use surfdata (no transient landuse),
when I set fertnitro=0 (red line in below plot)and fertnitro=45 (blue line),
I can see the fertilized is really added into the soil (SMINN), but the LAI keeps unchanged.
It seems the model just absorb the fertilizer into soil, the crop did not really use it....
Is this normal, or is there something wrong? What I really hope is when the fertilizer
is added, the crop should have larger LAI.

 

[oleson]

I don't really know. It looks like your changes caused some small differences (not bit-for-bit), so at least you know your changes took effect. Maybe LAI is constrained by something else or it doesn't need that nitrogen.