Friction

To each land use class and subnetwork is associated a numeric value (no value means that matching class is ignored).
This numeric value represents either a friction coefficient or a favorability class.

Coefficient

The classic method is to assign a friction coefficient modelizing the effective resistance of matching habitat to matching subnetwork species dispersal.

Classes de favorabilité

Favorabilty classes allows user to classify land use according to its quality without giving a quantified numeric value. Specified value then represents land use favorability class (for instance from 1 for unfavourable to 5 for very favourable).
Once favorability layer is created, user can compute potential distribution index to get a first look to study area without specifying coefficients (index is available in BioDispersal processing toolbox, see LINK for a step by step tutorial).

Fichier CSV

Coefficients can be imported from and exported to a CSV file.