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Root restricting layer depth

Dear Nat cap Members and Staffs, 

I am working on watershed of Nepal and I have Soil and terrain database(SOTER) for it alongwith shapefile. I tried to use soil data viewer but cannot proceed. Can you guide me to compute root restricting layer depth and PAWC? 



  • swolnyswolny Member, NatCap Staff
    Hi Shikshya -

    Soil databases are a bit complicated to use. You need to do manual calculations using the soil components (and sometimes across horizons) within each mapping unit, then apply those results to the mapping units to create the map that goes into the model. I don't have much experience working with the SOTER Nepal database, but we did use it for one project, where a colleague calculated soil depth. They took the largest soil depth for each soil component within a mapping unit, and did a weighted average across the soil component values, based on the proportion of each component within the mapping unit. Attached is an Excel table where she did these calculations, in case it helps. 

    I haven't tried calculating PAWC using SOTER, but it might help to look at the notes that I wrote about how to do a similar process with the Harmonized World Soil Database, which has a similar structure to the SOTER database. You can find those notes in this zipfile.

    Hopefully this helps.

    ~ Stacie

  • Thank you Stacie. I have computed soil depth in a similar way. I will now try to compute PAWC. 

    Thank you again. 

    ~ Shikshya
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