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)
- Author: J.Boehner, O.Conrad (c) 2008
- Menu: Terrain Analysis|Morphometry
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | Elevation | Grid (input) | DEM | - | - |
| Output | Slope Height | Grid (output) | HO | - | - |
| Valley Depth | Grid (output) | HU | - | - |
| Normalized Height | Grid (output) | NH | - | - |
| Standardized Height | Grid (output) | SH | - | - |
| Mid-Slope Positon | Grid (output) | MS | - | - |
| Options | Grid system | Grid system | PARAMETERS_GRID_SYSTEM | Grid system | - |
| w | Floating point | W | The parameter weights the influence of catchment size on relative elevation (inversely proportional). | Minimum: 0.000000
Default: 0.500000 |
| t | Floating point | T | The 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 |
| e | Floating point | E | The 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