Roots depth

MOHID Land forum. Questions and discussion related to MOHID Land
epelde.ane@gmail.com
MOHID Advanced user
Posts: 172
Joined: Thu Jan 01, 1970 00:00

Roots depth

Postby epelde.ane@gmail.com » Wed Mar 20, 2013 14:11

Hi!

I´m cheking the root depth of different crops and there is something not making sense to me..

In different cells with different vegetation I´ve seen (in the output.srvg) that in all of them the root depth reaches, as maximum, 0.6m. In the vegetation database this value is set to 2m in the crops Im checking, and the soil depth is not limiting cause the cells have more than 1m in all the cases.

Where can be coming from this value?

thanks!

Jauch
Site Admin
Posts: 98
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby Jauch » Fri Mar 22, 2013 11:10

Hello Ane :)

Could you put here the module vegetation input file and the plant database you're using?

Thanks.

epelde.ane@gmail.com
MOHID Advanced user
Posts: 172
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby epelde.ane@gmail.com » Fri Mar 22, 2013 12:38

Hi! :)
here it goes!

plant database for ID31:
VEGETATION_ID : 31
NAME : BARL
PLANT_TYPE : 5
BIOMASS_ENERGY_RATIO : 35
OPTIMAL_HARVEST_INDEX : 0.54
LAI_MAX : 4
GROWFRACTION_1 : 0.15
OPTIMAL_LAIMAXFRACTION_1 : 0.01
GROWFRACTION_2 : 0.45
OPTIMAL_LAIMAXFRACTION_2 : 0.95
GROWFRACTION_LAIDECLINE : 0.6
CANOPY_HEIGHT_MAX : 1.2
ROOT_DEPTH_MAX : 1.3
OPTIMAL_TEMPERATURE : 25
BASE_TEMPERATURE : 0
YELD_NITROGENFRACTION : 0.021
YELD_PHOSPHORUSFRACTION : 0.0017
OPTIMAL_NITROGENFRACTION_N1 : 0.059
OPTIMAL_NITROGENFRACTION_N2 : 0.0226
OPTIMAL_NITROGENFRACTION_N3 : 0.0131
OPTIMAL_PHOSPHORUSFRACTION_P1 : 0.0057
OPTIMAL_PHOSPHORUSFRACTION_P2 : 0.0022
OPTIMAL_PHOSPHORUSFRACTION_P3 : 0.0013
MINIMUM_HARVEST_INDEX : 0.2
RUE_DECLINE_RATE : 7
CO2_HIGH : 660
BIOMASS_ENERGY_RATIO_HIGH : 45
LAI_MIN_DORMANCY : 0
BIOMASS_FRAC_REMOVED_DORMANCY : 0
RADIATION_EXTINCTION_COEF : 0.65
TREE_YEARSTOMATURITY : -99
TREE_MAXIMUMBIOMASS : -99

I attach the vegetation data file.
thanks!

Jauch
Site Admin
Posts: 98
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby Jauch » Fri Mar 22, 2013 13:38

Seems that the vegetation file was not attached...

epelde.ane@gmail.com
MOHID Advanced user
Posts: 172
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby epelde.ane@gmail.com » Fri Mar 22, 2013 13:42

:)
is enough with this?

!Computation methods
WATER_UPTAKE_METHOD : 1
!1- according to root profile (feddes); 2-SWAT based (exponential and tresholds)
ROOT_PROFILE : 1
!1- triangular; 2- Constant; 3-Exponential (only read if WATER_UPTAKE_METHOD : 1)
WATER_UPTAKE_STRESS_METHOD : 1 !1-Feddes
!1-Feddes; 2- VanGenuchten (only read if WATER_UPTAKE_METHOD : 1)


<beginproperty>
NAME : root biomass
UNITS : kg/ha
DESCRIPTION : plant root biomass
EVOLUTION : 2
OLD : 1
FILE_IN_TIME : NONE
INITIALIZATION_METHOD : CONSTANT
DEFAULTVALUE : 0.
REMAIN_CONSTANT : 0
OUTPUT_HDF : 0
TIME_SERIE : 1
BOX_TIME_SERIE : 0
<endproperty>

<beginproperty>
NAME : root depth
UNITS : m
DESCRIPTION : plant root depth
EVOLUTION : 2
OLD : 1
FILE_IN_TIME : NONE
INITIALIZATION_METHOD : CONSTANT
DEFAULTVALUE : 0.0
REMAIN_CONSTANT : 0
OUTPUT_HDF : 0
TIME_SERIE : 1
BOX_TIME_SERIE : 0
<endproperty>

Jauch
Site Admin
Posts: 98
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby Jauch » Fri Mar 22, 2013 14:16

Ok.

Seems everything is right.

So, the most probable reason to the root depth get to 0.6 m only, instead of the maximum value on plant database, is that the soil depth, on those cells that you checked, is 0.6 m.
To be sure, you have to do a little math.

When you setup your model with Mohid Studio, using the Topography, it creates a soil bottom file and a soil depth file.
I'm assuming that you are checking the soil depth based on this file.

But when you run the model the first time, the soil bottom is "changed", based on the layers that you set in the geometry file. So, the depth can change.

Lets do this.

1. First, copy your original soil depth file, giving a new name to it.

2. Now, open both topography and the new bottom file (the one you are using to run the model), in excel.

3. Find the <BeginGridData2D> and <EndGridData2D> on both.

4. Subtract the soil bottom value from the topography value between the two tags found in the step 3.

5. replace all the values (between <BeginGridData2D> and <EndGridData2D>) in the soil depth copy you created with the result values in step 4.

Now you can open the new soil depth and check the depth at the cells.

epelde.ane@gmail.com
MOHID Advanced user
Posts: 172
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby epelde.ane@gmail.com » Mon Mar 25, 2013 08:32

Hi eduardo!
I did as you said and the soil depth in the cells is at least 1m (in the cells the roots where as maximum 0.6m deep the soil depth is 6m).
So, the problem is not coming from here, no?
thanks!

Jauch
Site Admin
Posts: 98
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby Jauch » Mon Mar 25, 2013 10:02

In fact, if the soil is deeper than the max root depth achieved, and also the maximum root depth (in the plant database) is higher, than the problem is other.
I'll ask David about this.

Jauch
Site Admin
Posts: 98
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby Jauch » Mon Mar 25, 2013 11:20

Hello Ane.

We found the "problem".
It is a conceptual issue. The plant database max root depth is updated, at the initialization of the model, to the lower depth where that ID exists.
This is why you get this behavior.

David will update the code and as soon this is done, I'll send to you a new executable.

Probably today, tomorrow at worst scenario ;)

epelde.ane@gmail.com
MOHID Advanced user
Posts: 172
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby epelde.ane@gmail.com » Mon Mar 25, 2013 11:32

Ok!! Thank you both!! :D

mm...so..right now the max depth is set to the lower depth where the ID is at. But, how is that possible if the lower depth is 1m?

Thank you a lot for answering all these questions :wink:

davidbrito
MOHID Advanced user
Posts: 189
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby davidbrito » Mon Mar 25, 2013 18:51

Hello,

there was this problem because the process was also considering the before last cell and not last cell bottom depth.
Now there is a version of the code where this is fixed and already in codeplex.

If you may have 32bit version I can send you. But if you use a 64bit I will ask Eduardo to send since I do not have that option.

Best regards,
David

epelde.ane@gmail.com
MOHID Advanced user
Posts: 172
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby epelde.ane@gmail.com » Tue Mar 26, 2013 07:52

yes, I have 32 bits one.
thanks!!

epelde.ane@gmail.com
MOHID Advanced user
Posts: 172
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby epelde.ane@gmail.com » Wed Mar 27, 2013 08:26

I´ve tried running with the executable you sent me, and after getting an error related to:

OVERLAND_CHANNEL_INTERACTION_METHOD keyword is deprecated.
Use CHANNEL_LINK_METHOD instead.
ReadDataFile - ModuleRunOff - ERR366

I changed the method to second and newer keyword, and it started running but bI got:

Number of iterations above maximum: 64
Check DT configurations
VariableSaturatedFlow - ModulePorousMedia - ERR01

So I changed the max_iterarions keyword of porous media from 1000 to 10000 but I got again exactly the same message.

Any idea please??

Jauch
Site Admin
Posts: 98
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby Jauch » Wed Mar 27, 2013 13:35

The change in keyword is ok. The other one was "too big". ;)

Regarding the problem of iterations.

Which DT_DURING_RAIN are you using (in basin input file)? Maybe lowering to something like 10 seconds can help.
If not, which value for CONDUTIVITYFACE (in porous media input file) are you using?
If you're using 1 (average) or 2 (maximum) you can try 3 (minimum) or 5 (geometric average). The minimum (3) usually works well when there are big changes in soil water content on short periods.

epelde.ane@gmail.com
MOHID Advanced user
Posts: 172
Joined: Thu Jan 01, 1970 00:00

Re: Roots depth

Postby epelde.ane@gmail.com » Wed Mar 27, 2013 14:05

Hi!!
I lowered the value of the rain_dt to 10sec (I was using 3600) but nothing. Then, I tried with the keyword conductivity_faces (I had set it to 3) but I changed it just in case to values 1, 2 and 5, but nothing..
same message about iterations :?


Return to “MOHID Land”

Who is online

Users browsing this forum: No registered users and 1 guest