Module Stream Power Index
Calculation of stream power index based on slope and specific catchment area (SCA).
SPI = SCA * tan(Slope)
References:
Moore, I.D., Grayson, R.B., Ladson, A.R. (1991):
'Digital terrain modelling: a review of hydrogical, geomorphological, and biological applications'
Hydrological Processes, Vol.5, No.1
- Author: O.Conrad (c) 2003
- Menu: Terrain Analysis|Hydrology|Topographic Indices
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | Slope | Grid (input) | SLOPE | - | - |
| Catchment Area | Grid (input) | AREA | - | - |
| Output | Stream Power Index | Grid (output) | SPI | - | - |
| Options | Grid system | Grid system | PARAMETERS_GRID_SYSTEM | Grid system | - |
| Area Conversion | Choice | CONV | - | Available Choices:
[0] no conversion (areas already given as specific catchment area)
[1] 1 / cell size (pseudo specific catchment area)
Default: 0 |
Command-line
Usage: saga_cmd ta_hydrology 21 [-SLOPE <str>] [-AREA <str>] [-SPI <str>] [-CONV <str>]
-SLOPE:<str> Slope
Grid (input)
-AREA:<str> Catchment Area
Grid (input)
-SPI:<str> Stream Power Index
Grid (output)
-CONV:<str> Area Conversion
Choice
Available Choices:
[0] no conversion (areas already given as specific catchment area)
[1] 1 / cell size (pseudo specific catchment area)
Default: 0