Rivermetrcs è un plugin di QGIS che permette il calcolo automatico della sinuosità degli alvei fluviali tramite GIS.
E’ disponibile la descrizione in inglese qui:
The plugin allows to calculate the river sinuosity using a vectorline representing the river axis. The vector line of river axis mustcontain only one feature and the coordinate reference system must be not geographical (long-lat) type. The plugin check this conditions by the validate geom button.
The sinuosity is calculated by considering a portion of thechannel centreline with fixed length (step value), progressively shifted downstream by a constant distance (shift value).
Sinuosity is obtained by dividing the fixed length of thecentreline tract by the straight-line between its end-points. Thecomputed sinuosity value is assigned to the midpoint of thecentreline tract. This approach have been proposed by Clerici e Perego, 2016.
The procedure to use the plugin is the following:
1) select a vector line representing the river axes from the combo box
2) select a a step value and a downstream shift value
3) press the validate geom button to check your layer
4) press the graph button to graph the sinuosity
5) select a csv file to save the graph sinuosity data
6) add breaks
7) press stop-breaks to create a new layer split following the breaks. The attribute table store the mean sinuosity value for any reach.