sar {spatialEco}R Documentation

Surface Area Ratio

Description

Calculates the Berry (2002) Surface Area Ratio based on slope

Usage

sar(x, s = NULL, scale = TRUE)

Arguments

x

A terra SpatRaster object

s

cell resolution (default is NULL and not needed if projection is in planar units)

scale

(TRUE/FALSE) Scale (row standardize) results

Details

SAR is calculated as: resolution^2 * cos( (degrees(slope) * (pi / 180)) )

Value

A terra SpatRaster class object of the Surface Area Ratio

Author(s)

Jeffrey S. Evans <jeffrey_evans@tnc.org>

References

Berry, J.K. (2002). Use surface area for realistic calculations. Geoworld 15(9):20-1.

Examples

 library(terra)
 elev <- rast(system.file("extdata/elev.tif", package="spatialEco"))
 ( surface.ratio <- sar(elev) )
   plot(surface.ratio)
    

[Package spatialEco version 2.0-2 Index]