SAGA-GIS Module Library Documentation (v2.3.0)

Module Relative Heights and Slope Positions

The module allows one to calculate several terrain indices from a digital elevation model.

General information on the computational concept can be found in:
- Boehner, J. and Selige, T. (2006): Spatial prediction of soil attributes using terrain analysis and climate regionalisation. In: Boehner, J., McCloy, K.R., Strobl, J. [Ed.]: SAGA - Analysis and Modelling Applications, Goettinger Geographische Abhandlungen, Goettingen: 13-28. (pdf)

Parameters

 NameTypeIdentifierDescriptionConstraints
InputElevationGrid (input)DEM--
OutputSlope HeightGrid (output)HO--
Valley DepthGrid (output)HU--
Normalized HeightGrid (output)NH--
Standardized HeightGrid (output)SH--
Mid-Slope PositonGrid (output)MS--
OptionsGrid systemGrid systemPARAMETERS_GRID_SYSTEMGrid system-
wFloating pointWThe parameter weights the influence of catchment size on relative elevation (inversely proportional).Minimum: 0.000000
Default: 0.500000
tFloating pointTThe parameter controls the amount by which a maximum in the neighbourhood of a cell is taken over into the cell (considering the local slope between the cells). The smaller 't' and/or the smaller the slope, the more of the maximum value is taken over into the cell. This results in a greater generalization/smoothing of the result. The greater 't' and/or the higher the slope, the less is taken over into the cell and the result will show a more irregular pattern caused by small changes in elevation between the cells.Minimum: 0.000000
Default: 10.000000
eFloating pointEThe parameter controls the position of relative height maxima as a function of slope.Minimum: 0.000000
Default: 2.000000

Command-line

Usage: saga_cmd ta_morphometry 14 [-DEM <str>] [-HO <str>] [-HU <str>] [-NH <str>] [-SH <str>] [-MS <str>] [-W <double>] [-T <double>] [-E <double>]
  -DEM:<str> 	Elevation
	Grid (input)
  -HO:<str>  	Slope Height
	Grid (output)
  -HU:<str>  	Valley Depth
	Grid (output)
  -NH:<str>  	Normalized Height
	Grid (output)
  -SH:<str>  	Standardized Height
	Grid (output)
  -MS:<str>  	Mid-Slope Positon
	Grid (output)
  -W:<double>	w
	Floating point
	Minimum: 0.000000
	Default: 0.500000
  -T:<double>	t
	Floating point
	Minimum: 0.000000
	Default: 10.000000
  -E:<double>	e
	Floating point
	Minimum: 0.000000
	Default: 2.000000