SAGA-GIS Tool Library Documentation (v9.1.2)

Tool Surface, Gradient and Concentration

Cellular automata are simple computational operators, but despite their simplicity, they allow the simulation of highly complex processes. This tool has been created to apply the concept of cellular automata to simulate diffusion and flow processes in shallow water bodies with in- and outflow, where monitoring data show concentration growth or decrease between the inflow and the outflow points. Parameters are for example nutrients like nitrate, which is reduced by denitrification process inside the water body.
Values of mask grid are expected to be 1 for water area, 2 for inlet, 3 for outlet and 0 for non water.


References


Parameters

 NameTypeIdentifierDescriptionConstraints
InputMaskGrid, inputMASK--
OutputSurfaceGrid, outputSURF--
GradientGrid, outputGRAD--
ConcentrationGrid, outputCONC--
OptionsGrid SystemGrid systemPARAMETERS_GRID_SYSTEM--
Surface Approximation ThresholdFloating pointSURF_E-Minimum: 0.000000
Default: 0.001000
Inlet ConcentrationFloating pointCONC_IN-Minimum: 0.000000
Default: 5.000000
Outlet ConcentrationFloating pointCONC_OUT-Minimum: 0.000000
Default: 3.000000
Concentration Approximation ThresholdFloating pointCONC_E-Minimum: 0.000000
Default: 0.001000
Minimum GradientFloating pointGRAD_MIN-Minimum: 0.000000
Default: 0.000000
NeighbourhoodChoiceNEIGHBOURS-Available Choices:
[0] Moore (8)
[1] Neumann (4)
[2] Optimised
Default: 0

Command-line

Usage: saga_cmd sim_hydrology 7 [-MASK <str>] [-SURF <str>] [-GRAD <str>] [-CONC <str>] [-SURF_E <double>] [-CONC_IN <double>] [-CONC_OUT <double>] [-CONC_E <double>] [-GRAD_MIN <double>] [-NEIGHBOURS <str>]
  -MASK:<str>       	Mask
	Grid, input
  -SURF:<str>       	Surface
	Grid, output
  -GRAD:<str>       	Gradient
	Grid, output
  -CONC:<str>       	Concentration
	Grid, output
  -SURF_E:<double>  	Surface Approximation Threshold
	Floating point
	Minimum: 0.000000
	Default: 0.001000
  -CONC_IN:<double> 	Inlet Concentration
	Floating point
	Minimum: 0.000000
	Default: 5.000000
  -CONC_OUT:<double>	Outlet Concentration
	Floating point
	Minimum: 0.000000
	Default: 3.000000
  -CONC_E:<double>  	Concentration Approximation Threshold
	Floating point
	Minimum: 0.000000
	Default: 0.001000
  -GRAD_MIN:<double>	Minimum Gradient
	Floating point
	Minimum: 0.000000
	Default: 0.000000
  -NEIGHBOURS:<str> 	Neighbourhood
	Choice
	Available Choices:
	[0] Moore (8)
	[1] Neumann (4)
	[2] Optimised
	Default: 0