[GRASS-user] v.surf.rst vs r.slope.aspect

[Edgar Pimiento]

Pierre,

-r.param.scale is more appropriate for high resolution elevation data than other modules. It permits to select the kernel (window size) for the estimation of parameters. Land surface parameters depend on DEM resolution and size of computation window. High elevation data are susceptible to noise and it is better to use a kernel larger than 3 when calculating slope and other parameters.

For references check module help and the following:  Wood, J.D. (1996) The geomorphological characterisation of digital elevation models PhD Thesis, University of Leicester, UK,http://www.soi.city.ac.uk/~jwo/phd; Hengl, T. and I. S. Evans (2009). Mathematical and Digital Models of the Land Surface. Geomorphometry- Concepts, Software, Applications. T. H. a. H. I. Reuter, Elsevier. Volume 33: 31-63; and Reuter, H. I., T. Hengl, et al. (2009). Preparation of DEMs for Geomorphometric Analysis. Geomorphometry- Concepts, Software, Applications. T. H. a. H. I. Reuter, Elsevier. Volume 33: 87-120.


Edgar Pimiento
e_pimiento at yahoo.com
Public Works Division, Shimane Prefecture, Japan

________________________________
From: Pierre Roudier <pierre.roudier at gmail.com>
To: GRASS <grass-user at lists.osgeo.org>
Sent: Tuesday, June 7, 2011 2:23 PM
Subject: [GRASS-user] v.surf.rst vs r.slope.aspect

Dear list,

For a project, I need to derive parameters like slope and aspect from
a high-res DEM from a LiDAR point cloud.

There are several way to do this in GRASS:

- v.surf.rst
- r.slope.aspect
- r.param.scale is a bit special and, I think, has a different purpose.

How do RST and r.slope.aspect compare? I can see (using difference
maps or the profile tool) the results are different, but I'm not too
sure which one to use at the end of the day.

Any thoughts/references on that?

Cheers,

Pierre

-- 
Scientist
Landcare Research, New Zealand
_______________________________________________
grass-user mailing list
grass-user at lists.osgeo.org
http://lists.osgeo.org/mailman/listinfo/grass-user