Annual Water Yield PAWC Raster

Hello, Community! Hope everyone is well during this time of crisis!
I have a question regarding the PAWC raster of the Annual Water Yield Model. I have data for soils of my state in Brazil, for which I actually had to use pedotransfer functions, and I managed to obtain PAWC per soil layer. How do I proceed now? Do I calculate a weighted average dividing by soil depth?

Thanks! Take care!

Hi @Victor_Maluf,

I’ll let others respond here but I did want to point to a prior post that might be useful: Annual Water yield model calibration. Further down @swolny links to some resources that might prove helpful.



Thank you, @dcdenu4!

Hi @Victor_Maluf -

Just to verify, when you say “per soil layer”, do you mean layers at different depths (also called horizons)?

If your values are in mm/m, then yes, you should divide the PAWC value for each layer by that layer’s soil depth (in mm) to get the AWC fraction. Then you can combine these layers into a single value by doing a weighted average based on their depth. This is definitely a simplification, and I’d be interested to hear if others do it differently.

~ Stacie

Hi, @swolny! Yes, “soil layer” also means “soil horizons”. My AWC is already in fraction. I’m looking at your “how to” material and it’s really helpfull! I found that the solution of using the weighted average is, so far, the best one. I also thought about using the higher value of AWC from soil horizons, or even the most common value. Maybe ignoring outlyers (too high or too low AWC values) is also a good idea.

Thanks @swolny and @dcdenu4! Take care!