Sediment Delivery Ratio Package

Model Entry Point

Sediment Delivery Ratio

Module contents

InVEST Sediment Delivery Ratio (SDR) module.

The SDR method in this model is based on:
Winchell, M. F., et al. “Extension and validation of a geographic information system-based method for calculating the Revised Universal Soil Loss Equation length-slope factor for erosion risk assessments in large watersheds.” Journal of Soil and Water Conservation 63.3 (2008): 105-111.

Sediment Delivery Ratio.

This function calculates the sediment export and retention of a landscape using the sediment delivery ratio model described in the InVEST user’s guide.

  • args['workspace_dir'] (string) – output directory for intermediate, temporary, and final files
  • args['results_suffix'] (string) – (optional) string to append to any output file names
  • args['dem_path'] (string) – path to a digital elevation raster
  • args['erosivity_path'] (string) – path to rainfall erosivity index raster
  • args['erodibility_path'] (string) – a path to soil erodibility raster
  • args['lulc_path'] (string) – path to land use/land cover raster
  • args['watersheds_path'] (string) – path to vector of the watersheds
  • args['biophysical_table_path'] (string) – path to CSV file with biophysical information of each land use classes. contain the fields ‘usle_c’ and ‘usle_p’
  • args['threshold_flow_accumulation'] (number) – number of upstream pixels on the dem to threshold to a stream.
  • args['k_param'] (number) – k calibration parameter
  • args['sdr_max'] (number) – max value the SDR
  • args['ic_0_param'] (number) – ic_0 calibration parameter
  • args['drainage_path'] (string) – (optional) path to drainage raster that is used to add additional drainage areas to the internally calculated stream layer
  • args['n_workers'] (int) – if present, indicates how many worker processes should be used in parallel processing. -1 indicates single process mode, 0 is single process but non-blocking mode, and >= 1 is number of processes.