transfspecies {BiodiversityR} | R Documentation |
Hypothetical Example of Turover of Species Composition
Description
This dataset documents the species composition of 19 sites that follow a specific sequence of sites as determined from unimodal species distributions. The dataset is accompanied by transfgradient
that documents the gradient in species turnover. This is a hypothetical example that allows to investigate how well ecological distance measures or ordination methods recover the expected best sequence of sites.
Usage
data(transfspecies)
Format
A data frame with 19 observations on the following 9 variables.
species1
a numeric vector
species2
a numeric vector
species3
a numeric vector
species4
a numeric vector
species5
a numeric vector
species6
a numeric vector
species7
a numeric vector
species8
a numeric vector
species9
a numeric vector
Details
The example in the Tree Diversity Analysis manual only looks at the ecological distance from the first site. Hence, only the first 10 sites that share some species with this site should be selected.
This dataset enables investigations of how well ecological distance measures and ordination diagrams reconstruct the gradient (sequence of sites). The gradient expresses how the sites would be arranged based on their species composition.
Source
Legendre, P. & Gallagher, E.D. (2001) Ecologically meaningful transformations for ordination of species data. Oecologia 129: 271-280.
References
Figure 3a.
Examples
data(transfspecies)
data(transfgradient)
plot(transfspecies[,1]~transfgradient[,1],xlab="gradient",
ylab="species abundance",type="n",ylim=c(0.5,8.5))
for (i in 1:9) {points(transfgradient[,1],transfspecies[,i],type="o",pch=i)}