spider {mvabund} | R Documentation |
Spider data
Description
data from spider2 directory, CANOCO FORTRAN package.
Usage
data(spider)
Format
A list containing the elements
- abund
- A data frame with 28 observations of abundance of 12 hunting spider species
- x
- A matrix of six (transformed) environmental variables at each of the 28 sites.
The data frame abund
has the following variables
- Alopacce
- (numeric) Abundance of the species Alopecosa accentuata
- Alopcune
- (numeric) Abundance of the species Alopecosa cuneata
- Alopfabr
- (numeric) Abundance of the species Alopecosa fabrilis
- Arctlute
- (numeric) Abundance of the species Arctosa lutetiana
- Arctperi
- (numeric) Abundance of the species Arctosa perita
- Auloalbi
- (numeric) Abundance of the species Aulonia albimana
- Pardlugu
- (numeric) Abundance of the species Pardosa lugubris
- Pardmont
- (numeric) Abundance of the species Pardosa monticola
- Pardnigr
- (numeric) Abundance of the species Pardosa nigriceps
- Pardpull
- (numeric) Abundance of the species Pardosa pullata
- Trocterr
- (numeric) Abundance of the species Trochosa terricola
- Zoraspin
- (numeric) Abundance of the species Zora spinimana
The matrix x
has the following variables
- soil.dry
- (numeric) Soil dry mass
- bare.sand
- (numeric) Cover bare sand
- fallen.leaves
- (numeric) Cover fallen leaves / twigs
- moss
- (numeric) Cover moss
- herb.layer
- (numeric) Cover herb layer
- reflection
- (numeric) Reflection of the soil surface with a cloudless sky
These variables have already been log(x+1)-transformed.
Details
The abundance of each species was measured as a count of the number of organisms in the sample.
Source
Data attributed to van der Aart & Smeenk-Enserink (1975), obtained from the spider2 directory, CANOCO FORTRAN package.
References
ter Braak, C. J. F. and Smilauer, P. (1998) CANOCO reference manual and user's guide to CANOCO for Windows: software for canonical community ordination (version 4). Microcomputer Power, New York, New York, USA.
van der Aart, P. J. M., and Smeenk-Enserink, N. (1975) Correlations between
distributions of hunting spiders (Lycos- idae, Ctenidae) and environmental
characteristics in a dune area. Netherlands Journal of Zoology 25,
1-45.
Examples
require(graphics)
data(spider)
spiddat <- as.mvabund(spider$abund)
plot(spiddat)
[Package
mvabund version 0.1-7
Index]