biogeo (version 1.0)

richness: Produced a species richness map

Description

Produce a species richness map from point records, without the use of a raster.

Usage

richness(dat, res = 10, option = "richness", buf = 5, ext = "")

Arguments

dat

A dataframe containing the required biogeo fields (see checkdatastr)

res

Spatial resolution for the richness map specified in minutes

option

Species richness or number of records per grid cell

buf

A buffer (in minutes) around the outer points to define the extent

ext

The extent for the map. This can be ext="p" to use the point data to calculate the extent. It could be an Exent object from the Raster package or a vector containing the following: minx, maxx, miny, maxy.

Value

A raster containing either species richness per grid cell or number of records per grid cell.

See Also

quickrich, richnessmap

Examples

ex1 <- c(15,35,-36,-23) # specify the extent
rich<-richness(dat,res=20,option="richness",buf=5,ext=ex1)