Hello guys,
I ran SDR for InVEST 3.7.0 but I got this error: “ValueError encoutered: Input Rasters are note the same dimensions. The following raster are not identical set ([(878,1365),(881,1412)]).” I know it is because of the drainage raster cause when I ran without this raster I got the corrects results of the model. Could some one help me please.
Thank you for the attention.
InVEST-Sediment-Delivery-Ratio-Model-(SDR)-log-2019-09-30–10_06_08.txt (3.5 KB)
Hi @Aline -
I’ve never used the drainage input to SWY, so am not sure if it has special coverage requirements (if there are, we should add that to the User Guide.) If it does have special requirements, I would guess that it would need to have the same spatial extent as the streams.tif layer that the model creates, which should be the same spatial extent as the DEM.
So, if you’re sure that this layer is causing the problems, I’d try re-processing your drainages layer such that it has the same extent as the DEM and see if that helps. It is also possible that the drainages layer can cover a larger extent than the DEM, just not a smaller one in either dimension. Please give it a try and let us know how it goes.
~ Stacie
Thank you for the repply Stacie. I aprecciate the help !
I tried re-processing the drainage layer but unfortunately the model got the error again.
I would like to make another question about what is writen in the guide of SDR. I don´t know if I can ask here.
Its written: “IC is a function of both the area upslope of each pixel (Dup) and the flow path between the pixel and the nearest stream (Ddn). If the upslope area is large, has lower slope, and good vegetative cover (so a low USLE C factor), Dup will be low, indicating a lower potential for sediment to make it to the stream. Similarly, if the downslope path between the pixel and the stream is long, has lower slope and good vegetative cover, Ddn will be low.”
I didn’t understand why Ddn would be low. Wouldn’t it be high?
Thansks for the attention.