| aravo {ade4} | R Documentation |
This dataset describe the distribution of 82 species of Alpine plants in 75 sites. Species traits and environmental variables are also measured.
data(aravo)
aravo is a list containing the following objects :
is a data.frame with the abundance values of 82 species (columns) in 75 sites (rows).
is a data.frame with the measurements of 6 environmental variables for the sites.
is data.frame with the measurements of 8 traits for the species.
is a vector with full species names.
The environmental variables are:
| Aspect | Relative south aspect (opposite of the sine of aspect with flat coded 0) |
| Slope | Slope inclination (degrees) |
| Form | Microtopographic landform index: 1 (convexity); 2 (convex slope); 3 (right slope); 4 (concave slope); 5 (concavity) |
| Snow | Mean snowmelt date (Julian day) averaged over 1997-1999 |
| PhysD | Physical disturbance, i.e., percentage of unvegetated soil due to physical processes |
| ZoogD | Zoogenic disturbance, i.e., quantity of unvegetated soil due to marmot activity: no; some; high |
The species traits for the plants are:
| Height | Vegetative height (cm) |
| Spread | Maximum lateral spread of clonal plants (cm) |
| Angle | Leaf elevation angle estimated at the middle of the lamina |
| Area | Area of a single leaf |
| Thick | Maximum thickness of a leaf cross section (avoiding the midrib) |
| SLA | Specific leaf area |
| Nmass | Mass-based leaf nitrogen content |
| Seed | Seed mass |
Choler, P. (2005) Consistent shifts in Alpine plant traits along a mesotopographical gradient. Arctic, Antarctic, and Alpine Research, 37,444–453.
data(aravo) coa1 <- dudi.coa(aravo$spe, scannf = FALSE, nf = 2) dudienv <- dudi.hillsmith(aravo$env, scannf = FALSE, nf = 2, row.w = coa1$lw) duditrait <- dudi.pca(aravo$traits, scannf = FALSE, nf = 2, row.w = coa1$cw) rlq1 <- rlq(dudienv, coa1, duditrait, scannf = FALSE, nf = 2) plot(rlq1)