hi,I have got the model output shows"Nodata" in the river network area(the white pixel),how do I solve it.Thank you.
Hi @steve -
The NDR model always gives NoData to stream pixels. This model routes nutrient over the landscape only until it reaches a stream, then stops calculating. No calculations are done within the stream, and no in-stream processes are considered, so no data is reported in the stream channel.
I see that you have a different post with unexpected output values - did you solve that problem in order to produce this result?
~ Stacie
Hi~Stacie
I downloaded the results of NDR model from Chaplin-Kramer R et al.（2019）and found the missing values of stream pixels were relatively rare in the map. But I failed to find relevant descriptions about handling these missing values in the article and its supplementary materials. Since many authors of this great article were in the Natural Capital Project, I wonder if there are some more detailed descriptions to deal with the missing values. Thank you.
Chaplin-Kramer R, Sharp R P, Weil C, et al. Global modeling of nature’s contributions to people[J]. Science, 2019, 366 (6462):255-258.
Hi @Char -
I didn’t work on that analysis, so am not sure how it was implemented - perhaps @rich knows? It may have used an older version of the model that handled streams differently. From my perspective, I have never done post-processing to fill in stream pixels. Since the model does no processing in the stream, we have no information on what kind of value to fill it in with.
If you simply don’t like the way it looks, you can fill in NoData values with a 0 or something else, but I still recommend indicating where the modeled streams are and being clear that we have no modeling output that describes what’s happening along the stream network.
~ Stacie
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