sac {fossil}

Calculate Species Area Curves

Description

Calculating a species area curve for a set of georeferenced localities

Usage

sac(lats, spp)

Arguments

lats

a table with a longitude and latitude column respectively as the first two columns, or a SpatialPoints object with longitude/latitude

spp

A matrix/data frame of species (rows) by samples/localities (columns)

Details

This will take a set of geographic coordinates along with a table of species by localities and return a list consisting of a matrix ($areavsspp) with a column of total area and of total species present, and a vector (ranks) with the order the samples were added in. The area is calculated by starting with the most central point, and adding those points closest to it, calculating a minimum spanning polygon as each new site is added, until all points are used.

Value

Returns a list of a matrix with columns of total area and total species recorded respectively and a vector of sample orders.

Author(s)

Matthew Vavrek

See Also

earth.dist, earth.poly

Examples

#fdata species/area relationship
data(fdata.lats)
data(fdata.mat)
a<-sac(fdata.lats, fdata.mat)
plot(log(a$areavsspp))