Hi I have run the SDR model and finally in the IC raster map some pixel value is “NoData”. Please help me to interpret this result and what is the solution?

Hi @hilu202 - In order to help, we could use more information. Please post the log file (.txt) that is produced in your Workspace, and an image where we can see where the pixels are that have NoData values. Thanks. Also, did you look at the other output files, including those in the “intermediate”…

HI i have checked different flow accumulation value and as it decreased the Null value in IC map increased and also the sediment export and USLE became more real. InVEST-Sediment-Delivery-Ratio-log-2022-03-31–12_30_20.txt (64.7 KB) ic_10.2_0111_02.tif (5.7 MB)

Thanks for the additional information @hilu202 . One thing I notice in the log file is that you have the Threshold Flow Accumulation (TFA) value set to 5. This is a very small number, especially since your pixel size is 12.5 meters. My initial guess is that this is causing a lot of your area to be co…

[image] swolny: d compare the stream.tif output with a real-world It works and the real stream map mached by the stream out put, there is another problem, the sediment export is not match with the real data, How can i increase it by 3 or 4 times?

Great, it sounds like adjusting the Threshold Flow Accumulation value helped fix that problem. For calibration, have you read the User Guide section Comparison with Observations ? It includes a paper from Hamel (2015) that includes information about calibrating against observed data. ~ Stacie

I have checked both Comparison with Observations and Hamel(2015), selecting IC0 and k parameter is still unclear for me. How can I change them till finding the best Sediment EXPORT result? What is the acceptable range of them?

The paper is not the best guide for how to implement calibration, but it does discuss performing a sensitivity analysis over a range of values for many of the model inputs, and using those to inform the calibration. So, you would do multiple model runs where you change, for example, the kb parameter…

Thanks for your accurate reply. I am looking for the acceptable range of variation of these two parameters.

SDR output IC with "NoData"?

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SDR output IC with "NoData"?

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