goeveg (version 0.2.0)

racurve: Rank-abundance curves

Description

This function draws a rank-abundance curve for community data. You can optionally add labels for a selected number of species. If you wish to draw multiple rank-abundance curves for selected samples use racurves.

Usage

racurve(matrix, main = "Rank-abundance diagram", nlab = 0, ylog = FALSE, frequency = FALSE)

Arguments

matrix

Community data, a matrix-like object with samples in rows.

main

The main title (optional).

nlab

Number of labeled species (default = 0). Species are labeled in decreasing order beginning from the highest relative abundance.

ylog

If set on TRUE the y-axis is displayed on a log-scale.

frequency

If set on TRUE frequencies of species are calculated instead of relative abundances.

Value

Returns an (invisible) list composed of:

abund

abundance of each species (in decreasing order)

rel.abund

relative abundance of each species (in decreasing order)

freq

frequency of each species (in decreasing order)

Details

Rank abundance curves or Whittaker plots (see Whittaker 1965) are used to display relative species abundance as biodiversity component. They are a means to visualise species richness and species evenness.

References

Whittaker, R. H. (1965). Dominance and Diversity in Land Plant Communities: Numerical relations of species express the importance of competition in community function and evolution. Science 147 : 250-260.

See Also

racurves

Examples

## Draw rank-abundance curve
racurve(schedenveg)

## Draw rank-abundance curve and label first 5 species
racurve(schedenveg, nlab = 5)

## Draw rank-abundance curve with log-scaled axis
racurve(schedenveg, ylog = TRUE)

## Draw rank-abundance curve with frequencies and no main title
racurve(schedenveg, frequency = TRUE, nlab = 1, main = "")