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0 values obtained for most number of sub-basins in NDR output

Hi all,

I ran the NDR model with 156 sub-basins. In my output table, I am getting 0 values for  n_export_total and p_export_total for 153 sub-basins. 
Though I have positive and reasonable values for all sub-basin in n_load and p_load. 

What might be a reason for this?  And is it possible practically to have no (0) nutrients exported ?


  • RichRich Administrator, NatCap Staff
    It is very unlikely 0 nutrients exported is a valid result. These kinds of errors are often caused because there are hydrological pits in the input DEM. Can you take a look at the flow accumulation raster in the intermediate directory of the workspace? If it looks like there are a lot of starts and stops, that's likely the issue and you can fill your DEM using ArcHydro or SAGA. If not, can you follow up again here?
  • Thanks, @Rich 
    It worked.
    I had previously filled the DEM in QGIS, using Raster fill option. As I was not getting any error I assumed that my inputs are fine. 
    Now that I checked my accumulation raster and saw starts and stops, I refilled by DEM using SAGA. 
    I ran the model again, now the values look fine. No 0 values in any sub-basin, it all makes sense now.

    Thanks again for quick reply. 

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