Point sampling of fish community

Description

This data set gives informations between a faunistic array, the total number of sampling points made at each sampling occasion and the year of the sampling occasion.

Usage

data(ichtyo)

Format

ichtyo is a list of 3 components.

tab

is a faunistic array with 9 columns and 32 rows.

eff

is a vector of the 32 sampling effort.

dat

is a factor where the levels are the 10 years of the sampling occasion.

Details

The value n(i,j) at the ith row and the jth column in tab corresponds to the number of sampling points of the ith sampling occasion (in eff) that contains the jth species.

Source

Dolédec, S., Chessel, D. and Olivier, J. M. (1995) L'analyse des correspondances décentrée: application aux peuplements ichtyologiques du haut-Rhône. Bulletin Français de la Pêche et de la Pisciculture, 336, 29–40.

Examples

data(ichtyo)
dudi1 <- dudi.dec(ichtyo$tab, ichtyo$eff, scan = FALSE)
s.class(dudi1$li, ichtyo$dat, wt = ichtyo$eff / sum(ichtyo$eff))