DESCRIPTION

r.northerness.easterness calculates northerness, easterness and the interaction between northerness and slope (northerness*slope). The user must specify the input elevation raster map.

NOTES

As aspect is a circular land-surface parameter, in ecology a sine or cosine transformation is often used to obtain a continuous gradient, stressing the north-south or east-west gradient (northness or eastness).

The GRASS GIS default aspect angles (cartesian) are converted to compass angles.

Calculated raster maps are:

The color of these raster maps are set to grey.

EXAMPLE

  # align region to DEM and habitat vector
  g.region -a raster=DEM align=DEM

  # run r.northerness.easterness
  r.northerness.easterness elevation=DEM

SEE ALSO

r.mapcalc, r.slope.aspect

REFERENCES

Olaya, V. 2009. Basic Land-Surface Parameters. In: Hengl, T. & Reuter, H.I. (eds.) 2009. Geomorphometry. Concepts, Software, Applications. Developments in Soil Science, Volume 33. Elsevier.

AUTHOR

Helmut Kudrnovsky

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