Relative Heights and Slope Positions
- Author: J.Boehner, O.Conrad (c) 2008
- Menu: Terrain Analysis | Morphometry
Description
This tool calculates several terrain indices related to the terrain position from a digital elevation model using an iterative approach. You can control the results with three parameters.
The parameter 'w' weights the influence of catchment size on relative elevation (inversely proportional).
The parameter 't' 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.
The parameter 'e' controls the position of relative height maxima as a function of slope. More details about the computational concept can be found in Boehner & Selige (2006).
References
- Boehner, J. & Selige, T. (2006): Spatial prediction of soil attributes using terrain analysis and climate regionalisation. In: Boehner, J., McCloy, K.R., Strobl, J. [Eds.]: SAGA - Analysis and Modelling Applications, Goettinger Geographische Abhandlungen, 13-28. online.
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 | - | - |
| w | floating point number | W | - | Minimum: 0.000000
Default: 0.500000 |
| t | floating point number | T | - | Minimum: 0.000000
Default: 10.000000 |
| e | floating point number | E | - | Minimum: 0.000000
Default: 2.000000 |
Command Line
Usage: saga_cmd ta_morphometry 14 [-DEM ] [-HO ] [-HU ] [-NH ] [-SH ] [-MS ] [-W ] [-T ] [-E ]
-DEM: Elevation
grid, input
-HO: Slope Height
grid, output
-HU: Valley Depth
grid, output
-NH: Normalized Height
grid, output
-SH: Standardized Height
grid, output
-MS: Mid-Slope Positon
grid, output
-W: w
floating point number
Minimum: 0.000000
Default: 0.500000
-T: t
floating point number
Minimum: 0.000000
Default: 10.000000
-E: e
floating point number
Minimum: 0.000000
Default: 2.000000