I am trying to develop a reasonable stream layer based on the accumulation output from r.terraflow, but am ending up with odd artifacts and broken tributaries (see attached graphic). Here are the steps I have taken:
- Run r.terraflow
- Run r.mapcalc accum_x="if(abs(accum_d8)>x,1,null())", where x=5000 for 10m DEM, x=555 for 30m DEM (trying to extract 50h accumulation streams)
- Run r.thin to create single-cell width layer
- Run r.to.vector to create vector layer
- Run v.clean to remove spurs
As you can see, however, the result is pretty unsatisfactory. Can anyone provide some advice on how this stream layer might be improved? I'm a bit stuck.
Thanks in advance,
Chris
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Christopher J. Fonnesbeck ( c h r i s @ f o n n e s b e c k . o r g )
Georgia Cooperative Fish & Wildlife Research Unit, University of Georgia