Rugosity is defined as the surface area divided by the planar area. For digital elevation models, there are two methods: "hvar" and "area".
The "hvar" method for calculating rugosity is described in Torres-Pulliza et al. (2004) and is based on height variations.
The "area" method uses the sp::surfaceArea() function and is detailed in Jenness (2004).
method is ignored if data is a mesh3D object.
In that case the function uses Rvcg::vcgArea() to calculate surface area of a triangular mesh of class mesh3d.
Usage
rg(
data,
L0,
method = "area",
parallel = FALSE,
ncores = (parallel::detectCores() - 1)
)Arguments
- data
Digital elevation model of class RasterLayer or a triangular mesh of class mesh3d.
- L0
Grain or resolution of calculation.
- method
If data is a RasterLayer methods "hvar" or "area" are allowed. Defaults to "hvar".
- parallel
Logical. Use parallel processing? Defaults to FALSE.
- ncores
Number of cores to use if parallel = TRUE. (Defaults to umber of available cores - 1)
References
Jenness, J.S. Calculating Landscape Surface Area from Digital Elevation Models. Wildlife Society Bulletin, Vol. 32, No. 3 (Autumn, 2004), pp. 829-839n
Torres-Pulliza, D., Dornelas, M.A., Pizarro, O. et al. A geometric basis for surface habitat complexity and biodiversity. Nat Ecol Evol 4, 1495–1501 (2020). https://doi.org/10.1038/s41559-020-1281-8