SAGA-GIS Tool Library Documentation (v7.2.0)

Tool Soil Moisture Content

The WEELS (Wind Erosion on European Light Soils) soil moisture model dynamically calculates the soil moisture based on the rules proposed by the DVWK (1996) with input data about:
- soil properties (grids: field capacity and permanent wilting point)
- land use (grid: crop types)
- climate (table: daily values of precipitation, temperature, air humidity)

References:
- DVWK - Deutscher Verband fuer Wasserwirtschaft und Kulturbau e.V. (1996): 'Ermittlung der Verdunstung von Land- und Wasserflaechen', DVWK Merkblaetter 238/1996, Bonn, 135p.
- Boehner, J., Schaefer, W., Conrad, O., Gross, J., Ringeler, A. (2001): 'The WEELS Model: methods, results and limits of wind erosion modelling', In: Catena, Special Issue

Parameters

 NameTypeIdentifierDescriptionConstraints
InputField Capacity [mm] (*)Grid (optional input)STA_FC--
Permanent Wilting Point [mm] (*)Grid (optional input)STA_PWP--
Land Use (*)Grid (optional input)LANDUSE--
OutputSoil MoistureGrid (output)DYN_W--
OptionsGrid systemGrid systemPARAMETERS_GRID_SYSTEM--
DefaultFloating pointSTA_FC_DEF-Minimum: 0.000000
Default: 20.000000
DefaultFloating pointSTA_PWP_DEF-Minimum: 0.000000
Default: 2.000000
DefaultIntegerLANDUSE_DEF-Default: -1
Climate DataStatic tableDYN_CLIMATE-3 Fields:
- 1. [8 byte floating point number] Precipitation (mm)
- 2. [8 byte floating point number] Temperature (2pm) (DegreeC)
- 3. [8 byte floating point number] Air Humidity (2pm) (%%)
Crop CoefficientsStatic tableSTA_KC-14 Fields:
- 1. [signed 4 byte integer] Land Use ID
- 2. [string] Name
- 3. [8 byte floating point number] January
- 4. [8 byte floating point number] February
- 5. [8 byte floating point number] March
- 6. [8 byte floating point number] April
- 7. [8 byte floating point number] May
- 8. [8 byte floating point number] June
- 9. [8 byte floating point number] July
- 10. [8 byte floating point number] August
- 11. [8 byte floating point number] September
- 12. [8 byte floating point number] October
- 13. [8 byte floating point number] November
- 14. [8 byte floating point number] December
(*) optional

Command-line

Usage: saga_cmd sim_hydrology 0 [-STA_FC <str>] [-STA_FC_DEF <double>] [-STA_PWP <str>] [-STA_PWP_DEF <double>] [-LANDUSE <str>] [-LANDUSE_DEF <num>] [-DYN_W <str>] [-DYN_CLIMATE <str>] [-STA_KC <str>]
  -STA_FC:<str>        	Field Capacity [mm]
	Grid (optional input)
  -STA_FC_DEF:<double> 	Default
	Floating point
	Minimum: 0.000000
	Default: 20.000000
  -STA_PWP:<str>       	Permanent Wilting Point [mm]
	Grid (optional input)
  -STA_PWP_DEF:<double>	Default
	Floating point
	Minimum: 0.000000
	Default: 2.000000
  -LANDUSE:<str>       	Land Use
	Grid (optional input)
  -LANDUSE_DEF:<num>   	Default
	Integer
	Default: -1
  -DYN_W:<str>         	Soil Moisture
	Grid (output)
  -DYN_CLIMATE:<str>   	Climate Data
	Static table
	3 Fields:
	- 1. [8 byte floating point number] Precipitation (mm)
	- 2. [8 byte floating point number] Temperature (2pm) (DegreeC)
	- 3. [8 byte floating point number] Air Humidity (2pm) (%)
	
  -STA_KC:<str>        	Crop Coefficients
	Static table
	14 Fields:
	- 1. [signed 4 byte integer] Land Use ID
	- 2. [string] Name
	- 3. [8 byte floating point number] January
	- 4. [8 byte floating point number] February
	- 5. [8 byte floating point number] March
	- 6. [8 byte floating point number] April
	- 7. [8 byte floating point number] May
	- 8. [8 byte floating point number] June
	- 9. [8 byte floating point number] July
	- 10. [8 byte floating point number] August
	- 11. [8 byte floating point number] September
	- 12. [8 byte floating point number] October
	- 13. [8 byte floating point number] November
	- 14. [8 byte floating point number] December