Fertilizer apply

[epelde.ane@gmail.com]

Hi!

I´ve just started applying some fertilizer and I´m doing some test, but here I come across with first questions related to this..

My setting is sth like:

-I have activated Porous media properties and runoff properties modules.
-In all Runoff properties, porousmedia properties and drainage network modules, I´ve created the nitrate property block.
-In Vegetation module, I´ve activated Nitrogen stress (althought I think it should work without this, right?) and fertilization.
-In vegetationparameters file, I´ve choosen an agricultural ID (for the main crop in the area) and inside the agricultural practices block, I´ve defined an application of 1000 kg/ha of a fertilizer which its mineral_n_fraction is 0.15, and this happens 10days later of the planting day.

I was expecting to see a pick in the nitrate concentration in the application day, but nothing happens. In fact, I set a default value of 10mg/l which was the starting value in the time serie, but in other simulation, after setting all the default values to 0mg/l, there is no nitrate in the porous media. So its like if I wasnt setting well the fertilizer application, no?

Do you see here something is missing?

Thanks again

[davidbrito]

Hello Ane,

you are applying 150kgN/ha and I think in only one application
if you multiply it by your cell area (i will do 200x200m or 4ha) you have 600 kg of nitrate to be applied. If the fraction to apply in surface is 1.0 than all 600 kg will go on surface cell.

if you take the first cell water content at the day previous of application (i will use 0.3) and your first cell is 0.1m than you have 0.3 * 0.1 * 40 000 = 1200 m3 of water.
If in porous media in the day previous to fertilization you have in surface layer 10mg/L (or g/m3) than you have 12kg of N in that layer.

So after the fertilization (you do not need a plant to be growing to fertilize and like this you do not have to account for uptake), if there is no rain input and water is not moving a lot in soil you should have 612 kg of N or around 500 mg/L after fertilization if my math is not wrong.

Are you looking to the surface layer of a cell that has fertilization?
Check the coordinates of the cell and the K must be the number of layers you have.

you have to check that you do not have this keyword on vegetation or you have the value 1
NUTRIENT_FLUXES_WITH_SOIL
(this keyword by default is always on (allow fluxes to soil) so you do not need to have it. it is used to debug)

for you to see the fluxes that are occuring between vegetation and soil use this (value 1):
FLUXES_TO_SOIL_OUTPUT
and it will create a new timeseries where you can see the fertilization fluxes.

Hope it helped.

David

[epelde.ane@gmail.com]

Hello david!

Ok, so I see how you calculate the nitrate in the cells, just one thing to do it right, as the vegetation output is daily, things like water content and so, you just obtain an average value for the day, right?

Now, I am applying 1000 kg of a fertilizer that has a fraction of N of 0.15 and then, the 0.2fraction of that gets into the soil trough surface and the rest trough sub-surface, what is what I´m seeing in the graph from .srvgf file(as expected) so, it is considering the fertilizer input. Then, in the same coordinates at different depths (middle layer and top ones) I´m getting output for porous media properties, but the graphs appear to be empty (nitrate concentration in porous media and also nitrate in river nodes)..

Do you have any idea what could be happening?

Thanks again,

[davidbrito]

ok.

forget now about river and other layers. The nitrate may in the simulation time never get to river.


In the soil in the surface cell at the day of fertilization you should have nitrate concentration going up.


The results are always instantneous and not averages. The concentration or water content is the value at the specified time of output.
If you want to test you can create more frequent outputs but you should see it. I would take the rain just to see that.


Can you post here the graph with the srvgf with the fertilization and in the same graph the porous media properties nitrate result in TOP cell.
Again you have to be sure that the you are plotting a cell at the top and that is a cell with the crop that is fertilized.


Best regards,
David

[epelde.ane@gmail.com]

Hi david!

I was trying to extend a bit the simulation so that I had more days after the fertilization apply so I could post it here as you asked me. But, after getting the graphs I told you, I made a change in the simulation (related to soil dry density property, which I set it by layers instead of a cte value, but thinking this error was related to that, I set it to the previous value).

The crash comes just with the application of the fertilizer, I remember that last week I had the same message and I fixed it just changing the day of application (which I dont understand what could be this owe to, stabilization or so? ) So now, I´m doing a simulation of 20 days and I´ve tried applying the fertilizer different days inside the simulated period, but nothing.
I get a message saying:

forrtl: severe (157): Program Exception - access violation Image PC Routine Line Source
MOHIDLand_release 0047D037 _MODULEPOROUSMEDI 5902 ModulePorousMediaProperties.F90
MOHIDLand_release 0047B6B5 _MODULEPOROUSMEDI 5107 ModulePorousMediaProperties.F90
MOHIDLand_release 004FA601 _MODULEBASIN_mp_P 5509 ModuleBasin.f90
MOHIDLand_release 004E9D4A _MODULEBASIN_mp_M 2962 ModuleBasin.f90
MOHIDLand_release 00501585 _MAIN__ 75 MohidLand.f90
MOHIDLand_release 00862A73 Unknown Unknown Unknown
MOHIDLand_release 007BE49C Unknown Unknown Unknown
kernel32.dll 76901174 Unknown Unknown Unknown
ntdll.dll 7732B3F5 Unknown Unknown Unknown
ntdll.dll 7732B3C8 Unknown Unknown Unknown

Can you tell me please if you know why do the message appear?
Lets see if I solve this to get to the other problem..

[davidbrito]

Hello Ane,

We need to put an error message warning on this so that the user knows what is. Beside the line.

You need to put
MIN_VALUE in nitrate or inorganic phosphorus the variables that are uptaken by vegetation. This keyword sets the minimum value of the property so you should put zero.

I will try to update the way the error message appears.

Best regards,
David

[epelde.ane@gmail.com]

Hi David!
solved, nitrates in the aquifer! I think that last week didnt work cause of the same reason I told you above that the error message was solved just changing the application day..
Thank you!!